topic: Freshwater Fish

topic: Freshwater Fish

Social media activity version | Lean version

New ban threatens traditional fishers in Brazil’s Mato Grosso state
- Legislation in effect since Jan. 1 has banned fishing in Mato Grosso state rivers for five years, with heavy opposition from environmental defenders and traditional fishers.
- The bill affects part of the Brazilian Amazon Rainforest, the Cerrado savanna and part of the Pantanal wetland, one of the largest continuous wet areas on the planet.
- Experts consider fishers in the region guardians of the rivers and fear the bill could eliminate traditional fishing in the state.

One of Colombia’s largest estuary ecosystems is drying up, communities warn
- Decades of sediment pollution, contamination and government infrastructure projects have disrupted the natural flow of saltwater and freshwater into the Ciénaga Grande of Santa Marta, one of Colombia’s key wetlands and a major estuary on the Caribbean Sea.
- Fish stocks have also plummeted, with profitable, big species being replaced by smaller ones and leaving fishing communities without their livelihoods.
- Although authorities claim that they are investing in the region, locals complain the autonomous corporation in charge is not taking steps to dredge the canals and that there isn’t enough transparency on how the money is being spent.

Report shows dire state of Mekong’s fish — but damage can still be undone
- A recent report by 25 conservation organizations raises alarm about the state of fish in the Mekong River, determining that at least 19% of species are threatened with extinction.
- The report calls for the global “Emergency Recovery Plan” for freshwater biodiversity to be implemented in the Mekong, with an emphasis on letting the river and its tributaries flow more naturally, improving water quality, protecting and restoring critical habitats and species, and curbing unsustainable resource extraction.
- Despite the threats, the report notes conservation bright spots, including the discovery of new species, and emphasizes that it is not too late to protect the river, its fish, and the millions of people who depend on it.

Ancient giant river dolphin species found in the Peruvian Amazon
- Paleontologists discovered a fossilized skull of a newly described species of giant freshwater dolphin in the Peruvian Amazon, which lived around 16 million years ago and is considered the largest-known river dolphin ever found.
- The ancient creature, measuring 3-3.5 meters (9.8-11.5 feet), was surprisingly related to South Asian river dolphins rather than the local, living Amazon river pink dolphin and shared highly developed facial crests used for echolocation.
- The discovery comes at a time when the six existing species of modern river dolphins face unprecedented threats, with their combined populations decreasing by 73% since the 1980s due to unsustainable fishing practices, climate change, pollution, illegal mining and infrastructure development.
- Conservation efforts are underway, including the signing of the Global Declaration for River Dolphins by nine countries and successful initiatives in China and Indonesia, highlighting the importance of protecting these critical species that serve as indicators of river ecosystem health.

Fishers’ memories on par with scientific data on historic catches: Study
- A new study investigated how the memories of about 400 fishers from traditional communities in Brazil can serve as sources of data on historic fishing effort and catch size.
- It measured the reliability of this “harvest recall data” by comparing it to other data collected by standard scientific methods.
- The researchers found that when considered as a whole, the fishers’ memories agreed with standard data collection methods about 95% of the time, which suggests that this recall method can be an effective fisheries management tool.

Migratory Amazonian catfish placed on the international protection list
- The gilded and piramutaba catfish (Brachyplatystoma rousseauxii and B. vaillantii, respectively) were recently placed on the Convention on the Conservation of Migratory Species (CMS) list, also known as the Bonn Convention.
- These fish carry out the longest freshwater migration on the planet: The gilded or “dorado” travels 11,000 kilometers (6,800 miles) between the mouth of the Amazon River and the foot of the Andes to lay its eggs; the piramutaba swims 5,500 km (3,400 mi).
- Both species are endangered due to overfishing and construction of hydroelectric plants on rivers in the Amazon; the dorado’s distribution range has shrunk by 37% because of the dams.

Gharial conservation plan leaves Nepal fishing communities searching for new jobs
- Since the creation of Chitwan National Park, some Indigenous Bote people who have lost access to their ancestral lands and livelihoods have been employed by the park as gharial keepers to help conserve the critically endangered species.
- However, community members say the park’s restrictions on their fishing livelihoods to protect the reptile species is taking a toll on their economic needs and restricting their rights; the possibility of working as gharial keepers and other livelihood alternatives are insufficient, they say.
- Many parents are now encouraging their children to migrate to Persian Gulf countries to work as migrant laborers in order to lead a better material life.
- Conservationists say restricting fishing is an important step in protecting the species, which would struggle to survive if many economically dependent communities fished in the rivers.

Amazon catfish must be protected by the Convention on Migratory Species COP-14 (commentary)
- The latest Convention on Migratory Species of Wild Animals (also known as the Bonn Convention) meeting (COP-14) is taking place in Uzbekistan this month, and the government of Brazil has proposed protections for two catfish species with extraordinary migrations, the dorado and piramutaba (manitoa).
- The dorado’s migratory journey for instance spans a distance of 11,000+ kilometers round trip, from the Andes to the mouth of the Amazon River, and along the way it connects multiple ecosystems and feeds local and Indigenous fishing communities, but is under increasing threat.
- “During COP-14, the dorado and piramutaba will take a prominent place thanks to the Brazilian Government’s proposal to include them in CMS Appendix II…It is essential that the governments at the meeting adopt Brazil’s proposal,” a new op-ed argues.
- This article is a commentary. The views expressed are those of the author, not necessarily Mongabay.

New guidebook supports U.S. tribal nations in adopting rights-of-nature laws
- A new guidebook aims to assist tribal nations across the United States in adopting legal frameworks that recognize the rights of nature.
- The growing rights-of-nature movement seeks to protect the environment by legally acknowledging its inherent right to exist and thrive independent of human use.
- The guide examines real-world challenges and pathways for passing laws and includes case studies of tribes that have enacted rights-of-nature laws through constitutions, ordinances and resolutions.
- The guide contains practical guidance on steps like surveying community perspectives, holding educational gatherings, and forming planning committees.

Indigenous effort in Bangladesh helps reverse endangered fish’s slide to extinction
- Unchecked logging and quarrying of rocks from streambeds in Bangladesh’s Chittagong Hill Tracts led to springs drying up and populations of putitor mahseer fish, an endangered species, disappearing.
- The situation was worsened by climate change impacts, characterized here by a more intense dry season during which even streams that once ran year-round now dry up.
- A project launched in 2016 and backed by USAID and the UNDP is working with Indigenous communities to reverse this decline, starting with efforts to cut down on logging and quarrying.
- As a result of these efforts, areas where forests have been conserved have seen the flow of springs stabilize and populations of putitor mahseer and other fish revive.

Salmon and other migratory fish play crucial role in delivering nutrients
- Pacific salmon can play a key role in transporting nutrients from marine to freshwater and terrestrial ecosystems.
- In the past, Pacific salmon and other anadromous fish that spawn in freshwater and spend part of their life in the ocean likely played a much larger role in global nutrient cycles, scientists find.
- But today, many populations of Pacific salmon and other anadromous fish are under pressure from habitat loss, overfishing, climate change, dams and other pressures that have greatly reduced their numbers, weight and ability to migrate freely.
- Population declines could further curtail their role in global nutrient transport in future, with increasing consequences, especially for nutrient-poor ecosystems that have relied in the past on migratory fish for significant nutrient additions.

Study: Fishing with pesticides and dynamite puts Ecuadorian Amazon in peril
- Illegal fishing with agrochemicals and explosives across several of Ecuador’s Amazonian states is an uncontrolled problem, causing long-lasting, irreversible damage to aquatic ecosystems, recent research has shown.
- The study links high levels of poverty to the wider practice of unsustainable fishing, and calls for tighter controls on the sale and availability of agrochemicals and dynamite across the country.
- Fish caught using toxic chemicals can be dangerous for human consumption, the study warns, and says there should be more action to help educate communities about these dangers.

Thailand tries nature-based water management to adapt to climate change
- With an economy largely underpinned by irrigated crops like rice, water is a crucial resource in Thailand. But as climate change exacerbates floods and droughts in the country, sustainable water management is an increasing challenge.
- Nature-based solutions that incorporate the natural processes of the country’s abundant rivers, floodplains and watershed forests are beginning to be trialed via various projects at large and small scales.
- A new report assesses the efficacy of two nature-based approaches to water management in Thailand, which represent a step away from the country’s typically top-down, hard-engineering approach and present several benefits to the environment and communities.
- However, environmental and societal tradeoffs, complex policy frameworks, and the need for greater understanding and expertise around the concept, design and implementation of nature-based approaches are barriers to their widespread implementation.

Last of the reef netters: An Indigenous, sustainable salmon fishery
- Reef net fishing is an ancient, sustainable salmon-harvesting technique created and perfected by the Lummi and other Coast Salish Indigenous people over a millennium.
- Rather than chasing the fish, this technique uses ropes to create an artificial reef that channels fish toward a net stretched between two anchored boats. Fishers observe the water and pull in the net at the right moment, intercepting salmon as they migrate from the Pacific Ocean to the Fraser River near present-day Washington state and British Columbia.
- Colonialism, government policies, habitat destruction, and declining salmon populations have separated tribes from this tradition. Today, only 12 reef net permits exist, with just one belonging to the Lummi Nation.
- Many tribal members hope to revive reef net fishing to restore their cultural identity and a sustainable salmon harvest but face difficulties balancing economic realities with preserving what the Lummi consider a sacred heritage.

Fish out of water: North American drought bakes salmon
- An unprecedented drought across much of British Columbia, Canada, and Washington and Oregon, U.S., during the summer and fall months of June through October could have dire impacts on Pacific salmon populations, biologists warn.
- Low water levels in streams and rivers combined with higher water temperatures can kill juvenile salmon and make it difficult for adults to swim upriver to their spawning grounds.
- Experts say relieving other pressures on Pacific salmon and restoring habitat are the best ways to build their resiliency to drought and other impacts of climate change.

Dam-building on Mekong poses risk to regional industries, report says
- A new report from WWF highlights how vital regional supply chains that rely on a healthy and connected Mekong River are undermined by hydropower development.
- Recent decades have seen scores of hydropower dams built on the Mekong River system, including 13 large-scale projects spanning the river’s mainstream channel, with hundreds more either planned or under construction.
- The report looks at how the economic value of hydropower in the Lower Mekong Basin measures up against its high economic trade-offs for five key sectors that underpin regional economies.
- The report provides recommendations for governments, investors and businesses to understand the true cost of hydropower and mitigate the inevitable risks they face over the decades to come.

Nepal’s water hyacinth helps exotic fish invade, harming native species: Study
- Exotic fish species such as Nile tilapia and glassfish were introduced by humans to Pokhara, Nepal’s Lake City for various reasons, and they compete with and prey on native fish species.
- A study suggests that water hyacinth, an invasive plant species, could be helping exotic fish species in Pokhara’s lakes to invade the lakes and reduce the diversity and abundance of native fish species.
- The researchers suggest that urgent conservation action is needed to control the spread of both water hyacinth and exotic fish species, and to protect the native fish species and the ecosystem of the lakes.

To keep track of salmon migrations in real time, First Nations turn to AI
- Partnering with First Nations, a new interdisciplinary study proposes harnessing artificial intelligence and computer-based detection to count and produce real-time data about salmon numbers.
- Monitoring their population when they return to the rivers and creeks is crucial to keep tabs on the health of the population and sustainably manage the stock, but the current manual process is laborious, time-consuming and often error-prone.
- Fisheries experts say the use of real-time population data can help them make timely informed decisions about salmon management, prevent overfishing of stocks, and give a chance for the dwindling salmon to bounce back to healthy levels.
- First Nations say the automated monitoring tool also helps them assert their land rights and steward fisheries resources in their territories.

Fishing ban extension raises hopes for iconic Amazon pink river dolphin
- The Amazon river dolphin, or boto, is an integral feature of the rainforest’s biodiversity and culture, and is central to several Indigenous tales.
- Even though the dolphin isn’t fished for human consumption, it’s become endangered over the decades because fishers use its flesh as bait for catching piracatinga catfish.
- The Brazilian government earlier this year renewed a moratorium on fishing of piracatinga, first imposed in 2014, in the hope of saving the dolphin, but experts say fishers have just been ignoring the rule.
- The measure became even more relevant in October following the detection of more than 100 dead dolphins in an Amazon lake — experts suspect that the deaths are directly linked to the extreme drought affecting the region.

Kenya’s Lake Victoria floods leave orphaned children to run their households
- Beginning in 2019, devastating floods on the shores of Kenya’s Lake Victoria have inundated homes, displaced families and left some orphaned children in charge of caring for their siblings and running the household.
- Many families continue to live in makeshift camps, hoping to rebuild and renew their lives; the effects of the flooding have been particularly harsh on children who have had to drop out of school or work to ensure the family’s survival.
- Experts attribute the floods to a combination of factors, including climate change, increased rainfall and lack of vegetation to control runoff; in 2015, an international research team predicted swiftly rising waters that could harm the region.
- UNICEF reports a concerning increase in the number of children affected by flooding in recent years, as climate change leads to more crises that can disrupt education, destabilize families and leave long-term effects on child development and psychosocial well-being.

In Sumatra’s Jambi, community forest managers fish to protect peatlands
- A community in Indonesia’s Jambi province has resorted to fish farming to raise money for its efforts to prevent wildfires in the community.
- In 2015, around 80% of the province’s peat forest was damaged during the Southeast Asia wildfire crisis.
- Jambi-based nonprofit KKI Warsi cites the number of peatland canals as the greatest barrier to replenishing the wetland.

AI unlocks secrets of Amazon river dolphins’ behavior, no tagging required
- Freshwater dolphins in the Amazon Basin navigate through flooded forests during the wet season using their flexible bodies and echolocation clicks.
- Researchers have combined advanced acoustic monitoring and AI to study the habits of endangered pink river dolphins (boto) and tucuxi in seasonally flooded habitats.
- They used hydrophones to record sounds in various habitats and employed convolutional neural networks (CNN) to classify the sounds as either echolocation clicks, boat engine noises, or rain — with high accuracy.
- Understanding the dolphins’ movements and behaviors can aid conservation efforts to protect these endangered species, as they face various threats such as fishing entanglement, dam construction, mining, agriculture and cattle ranching.

Popular aquarium fish from Thailand and Myanmar is new-to-science species
- Redtail garras, known for their bright orange tails and elongated snouts, are popular aquarium fish, but information about their biology has been scarce until recently — when they were described as a new species.
- Redtail garras primarily eat algae and arthropods by scraping them off rocks using specialized mouthparts. They have unique features like a snout covered in tubercles, which are hardened scales used as weapons.
- The species was named in honor of Nonn Panitvong, a Thai businessman and naturalist recognized for his efforts in biodiversity conservation.
- The late recognition of the redtail garra emphasizes the need to better understand biodiversity in understudied areas, and reflects the underestimate of fish diversity in Southeast Asia.

Fishing, dams and dredging close in on Peru’s river dolphins, study shows
- Amazon river dolphins in Peru are facing increasing threats from human activity, including fishing, proposed construction of dams, and dredging operations
- A study tracked the movements of dolphins in relation to fishing areas, dams and dredging sites, and found that 89% of their home range is subject to fishing activity.
- The research team observed that the dolphins in the study were, on average, located roughly 252 kilometers (157 miles) from the nearest proposed dam and 125 km (78 mi) from the closest proposed dredging site.
- The construction of the Amazon Waterway, aimed at improving navigability along waterways in Peru, involves dredging sites across four main rivers in the basin and could lead to ship collisions with dolphins, increased underwater noise, and habitat degradation.

Bangladesh ramps up freshwater fish conservation in bid for food security
- Bangladesh is reviving 39 native freshwater fish species through hatchery breeding, in an effort to secure stocks of commercially important fish.
- A quarter of the freshwater fish found in Bangladesh are threatened with extinction, according to a 2015 assessment, largely as a result of habitat loss, overfishing and pollution.
- In response to the decline, the Bangladesh government is breeding several species in captivity and distributing the fry for free to fish farmers.
- Bangladesh produces 4.6 million metric tons of fish a year, and is the No. 3 producer of freshwater fish globally.

Indonesia to expand ‘smart fisheries’ program aimed at empowering communities
- Indonesia will expand its smart fisheries village program, aiming to empower fishing communities to boost their productivity, achieve sustainability standards, and improve their overall economic welfare.
- Twenty-two fishing communities are enrolled in the initial batch of the program, which will focus primarily on fisheries, but also look to improve community welfare through tourism, public health interventions, financial literacy, and other initiatives.
- The participating communities are involved in catching or farming a wide range of seafood and other products, from octopus and tilapia to shrimp and organic salt.
- The fisheries sector employs about 12 million Indonesians, with most of the fleet today, about 650,000 vessels, operated by small-scale and traditional fishers.

Climate change, human pressures push Bangladesh’s ‘national fish’ into decline
- Bangladesh’s all-important hilsa fishery is declining amid pressures from human-driven factors and climate change, experts and authorities warn.
- The fish, Tenualosa ilisha, contributes around 12% of the total fish catch in Bangladesh, and the fishery employs at least 2.5 million people across the country.
- Several government conservation initiatives, including declaring six hilsa sanctuaries and two fishing bans during the year, have helped boost production in the past two decades.
- However, pressures persist, including rising salinity levels in the rivers where the fish spawn, discharge of pollution and agricultural runoff, and disruptions to water flow as dams are built upstream.

Seeking environmental DNA in Himalayan rivers: Q&A with Adarsh Man Sherchan
- Conservation geneticist Adarsh Man Sherchan is one of the leading experts keeping track of the impacts that Nepal’s dozens of dams are having on freshwater species.
- The Himalayan country has more than 120 hydroelectricity plants, many of which were built without prior aquatic biodiversity assessments.
- With advances in assessment technologies, notably environmental DNA (eDNA), and a growing cohort of trained experts like Sherchan, there’s a greater focus on identifying and mitigating the impacts of dams on river life.
- In an interview with Mongabay, Sherchan talks about why eDNA is a gamechanger for monitoring species, the process of getting eDNA samples from rivers, and why jeans and flip-flops are a no-go for fieldwork.

Award-winning community group in Sumatra cleans up lake
- A group of locals have since 2013 tried to clean up the trash pooling in Lake Sipin in the Sumatran province of Jambi.
- Their efforts have received national attention, with their leader, Leni Haini, awarded the country’s highest environmental award in 2022 by the government.
- Indonesia has announced a plan to restore 15 lakes (Sipin isn’t included) across the country by 2024, citing their high degree of degradation, chiefly sedimentation, which has resulted in their rapid shrinking and a decline in the biodiversity they host.
- These lakes are crucial in supporting the livelihoods of millions of Indonesians, serving as a source of freshwater, a form of flood control, and a site for fish-farming and tourism.

Conservationists aim to save critically endangered European eels on Italy’s Po River
- European eels (Anguilla anguilla) are critically endangered, their population having plummeted by 97% since 1980.
- Illegal fishing, dams and other barriers to their migration, droughts, pollution and habitat changes are putting the eels’ survival at risk.
- These eels reproduce once in their lifetime, only in the Sargasso Sea, where they die. Their unique lifecycle and migratory pattern further complicates conservation efforts.
- In Italy’s Po River Basin, researchers are working to conserve eels through interventions including the construction of fish passages to defragment rivers, reproduction in captivity and teaching fishers to recognize and release the likeliest breeders.

Residents of southeast Alaskan town debate mine that’s bound to change region
- After years of debate, a proposed mine in southeast Alaska near the Chilkat River has a permit to dig an exploratory tunnel and release wastewater.
- The mine has become a divisive topic in the town of Haines, where the Chilkat River sustains the region’s thriving fishing industry.
- Some residents are concerned about how the project could impact salmon in the river and their fishing jobs.
- Others believe the mining companies running the project will be responsible when it comes to protecting the river, while providing jobs in mining.

Second chance for Lula as controversial Amazon dam goes up for renewal
- In the biological and cultural hotspot of the Volta Grande in Brazil’s Amazon, Indigenous communities and scientists have teamed up to monitor the impacts of the Belo Monte hydroelectric project, one of the biggest in the world.
- The dam complex has diverted 80% of the Xingu River’s water flow, significantly affecting the aquatic life in the Volta Grande river bend and pushing the entire ecosystem toward collapse, along with the local communities who rely on it.
- The complex’s environmental license, which lasts six years and dictates the amount of water flowing through Belo Monte, is currently up for review by the federal environmental protection agency, IBAMA.
- President Luiz Inácio Lula da Silva played a key role in pushing for the construction of Belo Monte, and now, back in power, can influence a new path for the environment and local communities, activists say.

Spamming streams with hatchery salmon can disrupt ecosystems, study finds
- In a new study, researchers found that releasing hatchery-bred native masu salmon into freshwater streams in Hokkaido, Japan, destabilized the local ecosystems.
- Overall, the study found that the total number of fish, and number of different species, both declined in the long term due to greater competition for resources like food and preferred feeding spots.
- Masu salmon populations also did not increase in the long term, the research found.
- With hatchery releases increasing in many areas — and for many species — the findings add to the ongoing debate over their wider effects on wild fish populations.

‘Chasing giants’: Q&A with megafish biologist and author Zeb Hogan
- Earth’s freshwater ecosystems are among the most at risk from human-induced threats including overfishing, dam building, pollution and climate change.
- But biologists know relatively little about the animals that live in the murky depths of our rivers and lakes, perhaps least of all about some of their largest inhabitants.
- In a new book, fish conservation biologist Zeb Hogan teams up with journalist Stefan Lovgren to get to the bottom of a curious question: What is the world’s largest freshwater fish?
- An exploration of the world’s freshwater ecosystems from Australia to the Amazon, “Chasing Giants” also looks into the range of threats giant fish face the world over and what scientists, policymakers and the public can do to support their conservation.

Indigenous women in Colombia protect rich Amazonian wetland from overfishing
- Dozens of Indigenous women in Colombia’s Amazon are monitoring, managing, raising awareness and restoring a wetland ecosystem impacted by overfishing.
- After partnering with environmental organizations to establish a fishing agreement in the area, they have witnessed the increase and recovery of fish species such as sardines, catfish and the pirarucu (Arapaima gigas).
- The wetland area of Lake Tarapoto, located in the department of Amazonas in southern Colombia, provides a habitat for numerous aquatic animals and supports the livelihoods of 22 Indigenous communities.

Robust river governance key to restoring Mekong River vitality in face of dams
- Billions of cubic meters of Mekong River water are now harnessed behind dams in the interests of power generation, severely affecting crucial physical and biological processes that sustain the river’s capacity to support life.
- As the pace of hydropower development continues to pick up across the river basin, cracks in the region’s dated and limited river governance systems are increasingly exposed.
- Major challenges include the lack of formal, legally binding regulations that govern development projects with transboundary impacts, and a legacy of poor engagement with riverside communities who stand to lose the most due to the effects of dams.
- Experts say that open and honest dialogue between dam developers and operators is needed to restore the river’s natural seasonal flow and ensure the river’s vitality and capacity to support biodiversity and natural resources is sustained.

As hydropower dams quell the Mekong’s life force, what are the costs?
- The Mekong River is one of Asia’s longest and most influential waterways, sustaining extraordinary species and biodiverse ecosystems and providing nutrition for millions via its fertile floodplains and unparalleled fisheries.
- But over the past few decades, the construction of hydropower dams has undermined the river’s capacity to support life: more than 160 dams operate throughout the Mekong Basin, including 13 on the river’s mainstream, with hundreds more either planned or under construction.
- Besides severing fish migration routes and natural sediment transport throughout the river system, the dams affect the river’s natural seasonal ebb and flow, an ancient rhythm alongside which ecosystems have evolved.
- Communities, scientists and decision-makers now face unprecedented challenges as fish catches dwindle, riverbanks erode, ecosystems collapse and the delta inexorably sinks.

Fish kills leave Kenya’s Lake Victoria farmers at a loss, seeking answers
- According to a Kenyan government report, fish farmers in sections of Lake Victoria lost more than 900 million Kenyan shillings ($7.2 million) in massive fish kills in November 2022.
- Scientists attribute the fish kills to reduced levels of dissolved oxygen likely due to a natural phenomenon called upwelling, which can be exacerbated by climate change and extreme weather.
- Local farmers who lost their fish, however, attribute the die-offs to pollution from Lake Victoria industries, which agencies have accused of discharging untreated effluent into the lake in recent years.

Is it safe to eat? Bangladesh fish exposed to hormones, antibiotics and toxic waste
- Bangladesh has recently achieved remarkable success in freshwater fish production, with more than 1.25 million metric tons of freshwater fish produced in 2020.
- The use of antibiotics in fish culture and hormones in artificial fish breeding bring into question the safety of Bangladesh’s food supply, as exposure to high levels of these substances can harm human and environmental health.
- Research shows that 88% of fish farmers do not have proper knowledge of antibiotics use, and 81% are unaware of effective chemical dosages in fish farming.
- In addition, toxic industrial wastes containing heavy metals released into the aquatic environment may enter the food chain through biomagnification and may cause various health problems in humans.

Kenyan science interns turn Lake Victoria’s fish waste into oil and flowers
- Fish processing on Lake Victoria in Kenya generates tons of waste that harms the environment and leads to oxygen depletion and algal blooms that threaten native aquatic species.
- Science interns at the Kenya Marine and Fisheries Research Institute have developed a way to extract valuable fish oil from the waste, and they are also making decorative flowers from fish scales.
- These innovations are part of a growing trend of recycling Lake Victoria’s fish waste, turning it into goods that can be sold in local communities.
- Scientists aim to reduce the environmental harms of fish waste through innovations that could eventually be scaled up to meet growing national and international demands for fish oil and other products.

Loss of wetlands threatens South Sumatra’s rich fish-preserving tradition
- Rural communities in South Sumatra, an Indonesian province that’s two-fifths wetlands, have long relied on catching freshwater fish as a source of livelihood.
- The region is renowned for its variety of preserved fish products, which are sold throughout Indonesia.
- However, the wetlands are disappearing at a rapid rate, filled in to make way for oil palm plantations and highways, and threatening the region’s long-running fish-preserving tradition.
- Today, most of the freshwater fish processed here comes from fish farms, and include exotic species not native to the region, which some say doesn’t taste as good as the traditional species.

A freshwater giant is a boon to Bolivian fishers, but an unknown for native species
- Paiche or arapaima (Arapaima gigas) was introduced in Bolivia in 1976 by accident from Peru, and though initially rejected as an exotic species, is today prized by local fishers as a boon to the economy.
- There’s no research on the potential damage caused to riverine ecosystems in the Bolivian Amazon region due to the arrival of paiche, but native fish species have disappeared in some areas where the freshwater giants thrive.
- The Bolivian government has not classified paiche as an invasive species, with some official studies recommending controlling rather than eradicating its population.
- Paiche fishing has also been encouraged as an economic boon to rural communities, where the species accounts for up to 70% of fishers’ catch.

Herders turn to fishing in the desert amid severe drought, putting pressure on fish population
- As Northern Kenya’s unabating drought continues, a growing wave of pastoralists are finding it challenging to keep their livestock alive and are switching to fishing in Lake Turkana, the world’s largest desert lake.
- However, environmentalists, fishing authorities, and some fishers worry that potential overfishing and increased pressures on fish populations will cause a collapse in fish stocks and the lake’s ecosystem.
- Authorities are also concerned about the rampant use of illegal fishing gear, such as thin mesh nets that catch undersized fish in shallow breeding zones, and an illegal tilapia smuggling network draining the lake by the tons.
- Though no studies have yet been done to assess fish populations, some environmentalists and fishers are calling for better enforcement of regulations to keep livelihoods afloat.

Bangladesh bans suckermouth catfish in light of threats to native fish species
- Considering its aggressive breeding nature and the threats the species poses to native fish populations, the Bangladesh government has recently banned suckermouth fish.
- The suckermouth catfish is mainly an aquarium species that was imported into Bangladesh in the 1980s as an ornamental fish and later introduced into water bodies that are home to the country’s main sources of native fish.
- However, in recent years, the number of suckerfish has increased manifold as local fish species have decreased.
- Earlier, in 2002, Bangladesh banned two other fish species: African catfish and piranhas.

Sustainable fish farming & agroecology buoy Kenyan communities
- In Kenya, small-scale onshore aquaculture combined with sustainable agroecology practices is boosting food security and incomes for smallholder farmers.
- Though most of these farms are quite small, a large amount of protein can be raised in fish ponds filled with rainwater.
- Fed with combinations of food waste and crop residues from agroforestry and organic farming, fish like tilapia can be raised sustainably and profitably.
- Nine counties have invested in supporting such aquaculture projects, with an estimated 300 fish farmers in the Gatunga region of central Kenya alone.

Banned but abundant, gillnets pose main threat to Bangladesh’s river dolphins
- Bangladesh is home to around 2,000 Ganga River dolphins and 6,000 Irrawaddy dolphins, found mostly in the Sundarbans, the world’s largest mangrove forest.
- Both species, considered threatened on the IUCN Red List, run a high risk of entanglement in the gillnets used by local fishers.
- Gillnets are banned in Bangladesh, but remain popular among local fishers, with the government unable to crack down on their use.
- To conserve the freshwater dolphins, the government has embarked on a 10-year action plan that includes declaring more areas as dolphin sanctuaries and raising awareness among fishers.

As sea lice feast away on dwindling salmon, First Nations decide the fate of salmon farms
- Increased sea lice infestations, scientists say are caused by salmon farms, threaten the already-vulnerable wild Pacific salmon populations in western Canada, worrying conservationists and First Nations.
- Three First Nations in the region are now deciding on the future of open net pen Atlantic salmon farms dotting the channels and waterways in and around their territories. They hope their decisions will pave the way to protect wild salmon, a culturally important species.
- So far, ten farms have been closed and the future of seven farms are to be decided this year, in 2023.
- The impact of the closure of the farms on local sea lice and wild salmon populations is still unclear, say scientists, and more time to monitor the data is needed.

Series of small dams pose big cumulative risk to Amazon’s fish and people
- Small hydropower plants and small-scale fish farming in the Brazilian Amazon basin are often thought to cause negligible environmental harm, yet a new study reveals their cumulative damage is greatly underestimated and can be more impactful than large dams.
- Dwindling fish populations caused by the construction of thousands of small dams has impacted the livelihoods of millions of Indigenous and riverside people who depend on fishing for food, income and culture.
- Small hydropower plants and aquaculture farming are encouraged through economic incentives, simple licensing procedures, and loose requirements for environmental impact assessments before construction.
- More than 350 dam proposals in the Amazon basin are under consideration and 98 medium-sized dams will be prioritized in Brazil as of next year, ensuring the construction of hydropower plants will continue.

Shadows of oil in Peru: Shipibo people denounce damage, contamination left by company
- Community members guided a team of journalists to the creeks and land of Canaán de Cachiyacu and Nuevo Sucre, in the district of Contamana in Peru’s Loreto region, to demonstrate how they have been affected by the various spills attributed to the Maple Gas oil company for over 25 years.
- Shipibo community members say that due to contaminated water, they still suffer from illnesses and their farms no longer produce crops. The contract established that the company must comply with environmental protection laws, but Perupetro confirmed that it simply abandoned its operations.
- Mongabay Latam traveled to two Indigenous communities on the banks of the Ucayali River and listened to the concerns of their residents regarding the serious environmental impact that they claim was caused by the operations in Block 31-B and Block 31-E.

‘Europe’s rarest fish’ numbers spawn hopes for species’ survival
- The asprete, a rare freshwater fish found in Romania, was once considered extinct after dam construction destroyed much of its habitat.
- The fish’s existence was confirmed by surveys conducted in the last 50 years but only a few were thought to survive in Romania’s Vâlsan River. In 2020, an official estimate suggested only 7 to 10 individuals remained.
- However, a 2022 survey expedition found 58 specimens across a 15-kilometer (9.3-mile) stretch of the river, raising hopes that the species could be saved from extinction.
- Experts say conservation efforts, as well as more robust survey attempts, led to the higher population count.

Amid Mexico’s Day of the Dead, a fish declared extinct comes back to life
- Amid Mexico’s Day of the Dead festivities, a community released thousands of golden skiffia fish back into the species’ native range in the Teuchitlán River in Jalisco state.
- The fish, declared extinct in the wild in 1996, were part of a captive-breeding program and nearly 10 years of restoration work to restore their habitat and remove some of the threats that would prevent successful reintroduction.
- Freshwater fish are the most threatened group of vertebrates on Earth, with scientists estimating that one out of three is threatened with extinction.
- This golden skiffia reintroduction is part of the Fish Ark Mexico project, which works to conserve highly threatened species of freshwater fish in Central Mexico, including 39 species of splitfins, from the family Goodeidae.

Fish eggs return to Bangladesh’s Halda River following conservation efforts
- The Halda River, considered the world’s only natural gene bank for several pure Indian carp species, as well as home to dozens of endangered Ganges River dolphins, has made a comeback after fish eggs all but disappeared from the river several years ago.
- Historical records say around 4,000 kilograms (8,818 pounds) of fish eggs could be found in the river in 1941, but that number nearly hit zero in 2016 due to overexploitation and industrial pollution.
- Since 2018, the Bangladesh government has made robust conservation efforts, including steps to declare the river an Ecologically Critical Area and fish heritage site.
- In 2020, about 424 kgs (935 lbs) of fish eggs were found in the river; however, yields have since fallen after an unexpected tropical cyclone, Amphan, triggered salinity intrusion and there was low rainfall during the monsoons.

Saving the economically important hilsa fish comes at a cost to Bangladesh fishers
- Many fishers across Bangladesh say they still haven’t received the compensation promised by the government during a three-week ban on fishing of hilsa, the country’s most important fish.
- The ban ends on Oct. 28, and the government was supposed to hand out 40-kilogram (88-pound) rice packages to eligible fishers at the start of it, but some of the aid may have allegedly been embezzled by local officials.
- Almost half a million fishers are directly involved in the hilsa fishery in Bangladesh, with another 2 million indirectly involved; hilsa accounts for an eighth of total fish production and more than 1% of GDP in Bangladesh.
- In light of the fish’s importance, the government has since the 2000s enforced two bans a year, to allow the fish to breed and to protect the juveniles.

Habitat loss, climate change threaten Bangladesh’s native freshwater fishes with extinction
- There were at one time more than 300 native freshwater fish species in Bangladesh, but many have disappeared while others are on the verge of extinction due to habitat loss, overfishing, pollution and climate change.
- Open rivers and other bodies of water in Bangladesh are dwindling fast due to development interventions, unplanned urbanization, encroachment and siltation, which are destroying the habitats of indigenous fish species.
- According to the International Union for Conservation of Nature (IUCN), the statuses of 64 freshwater fish species in Bangladesh range from vulnerable to critically endangered while 30 have become extinct in the wild during the last 30 to 40 years.
- Bangladesh Fisheries Research Institute (BFRI) has so far revived 37 out of 67 species that disappeared from the wild through captive breeding programs and conservation efforts.

“Largest of its kind” dam in Cameroon faces backlash from unimpressed fishmongers
- Cameroon is constructing a new 420-megawatt capacity hydroelectric dam in Batchenga, aiming to reduce the country’s significant energy deficit by 30%.
- The massive dam project is impacting several villages where fishing is an essential part of the local economy. Several professional bodies, including fishmongers, fishermen and restaurant owners, have lost their livelihoods due to the dam’s construction.
- Fishmongers in one nearby village, Ndji, are becoming increasingly desperate for proper compensation as the amounts paid by the Nachtigal Hydro Power Company is not enough to make ends meet, they say.
- Civil society organizations are also accusing Nachtigal of seriously violating environmental standards during dam construction, despite the company continuously receiving environmental compliance certificates by the government.

The mine leak was bad. The DRC and Angola’s response are no better, report says
- In July 2021, an Angolan diamond mine leaked large amounts of polluted water into the Kasai River Basin which stretches across Angola and the Democratic Republic of Congo.
- Twelve people were killed, a further 4,400 fell ill and an estimated 1 million more were affected by the polluted water.
- Fourteen months later, the DRC government has not released full results of tests conducted on the rivers, but a ban on drinking the water from the Kasai and Tshikapa rivers remains in place.
- An independent report published in September 2022 has found that the leak killed off much of the rivers’ aquatic life, with severe and ongoing impacts on river-dependent communities.

Catfished: New species described from DRC after mistaken identity
- Scientists recently identified a new species of air-breathing catfish, Clarias monsembulai, in the Democratic Republic of Congo’s Salonga National Park — the first new species of catfish in the Clarias genus to be described in 42 years.
- It was named after Congolese researcher Raoul Monsembula, who collected samples of the species in 2006 and 2010 without realizing at the time that the fish was unknown to science.
- Experts say that species discoveries are very common in Salonga National Park due to the region’s rich biodiversity as well as the limited amount of research being done there.
- However, the area also faces numerous threats, including poaching and the possibility of fossil fuel extraction.

Humans are dosing Earth’s waterways with medicines. It isn’t healthy.
- Medicines, chemical formulations that alleviate much human suffering, can also be significant pollutants, with active ingredients often excreted from the human body and entering waterways. However, the intensity of this contamination and of its impacts has not been well researched.
- A study published in June analyzed samples from 1,000 sites along waterways in more than 100 nations, looking for 61 active pharmaceutical ingredients (APIs). Their results suggest that concentrations of at least one API breached safe levels for aquatic life at nearly 40% of sites tested globally.
- Some pharmaceuticals are endocrine disruptors (EDCs), which mimic hormones and interfere harmfully with the endocrine system in various organisms, while other drugs are linked to antimicrobial resistance (AMR), considered one of the biggest threats to human health and well-being today.
- Despite growing awareness among scientists, there is no systematic reporting of waterway pollution by medicines, or impacts on ecological health. Currently, many human-excreted pharmaceuticals enter directly into waterways, or pass through existing wastewater treatment facilities. Fixing the problem will be very expensive.

Cambodian mega dam’s resurrection on the Mekong ‘the beginning of the end’
- Cambodian authorities have greenlit studies for a major hydropower dam on the Mekong River in Stung Treng province, despite a ban on dam building on the river that’s been in place since 2020.
- Plans for the 1,400-megawatt Stung Treng dam have been around since 2007, but the project, under various would-be developers, has repeatedly been shelved over criticism of its impacts.
- This time around, the project is being championed by Royal Group, a politically connected conglomerate that was also behind the hugely controversial Lower Sesan 2 dam on a tributary of the Mekong, prompting fears among local communities and experts alike.
- This story was supported by the Pulitzer Center’s Rainforest Investigations Network where Gerald Flynn is a fellow.

In the Mekong Basin, an ‘unnecessary’ dam poses an outsized threat
- A dam being built in Laos near the border with Cambodia imperils downstream communities and the Mekong ecosystem as a whole, experts and affected community members say.
- The Sekong A dam will close off the Sekong River by the end of this year, restricting its water flow, blocking vital sediment from reaching the Mekong Delta in Vietnam, and cutting off migration routes for a range of fish species.
- Experts say the energy to be generated by the dam — 86 megawatts — doesn’t justify the negative impacts, calling it “an absolutely unnecessary project.”
- This story was supported by the Pulitzer Center’s Rainforest Investigations Network where Gerald Flynn is a fellow.

Human pressures strain Lake Tanganyika’s biodiversity and water quality
- As fishing pressure has increased on Lake Tanganyika, its level has also been rising, inundating shoreline communities.
- Sedimentation as a result of farming, infrastructure projects and deforestation is causing the water level to rise and the lake to expand.
- This has not led to an increase in fish populations, however, and what little data exist suggest that the lake’s overall biodiversity–probably including hippos and Nile crocodiles–is declining.
- An EU-funded plan to coordinate management of the lake by all countries that share it aims to address some of the knowledge gaps, but is itself hobbled by budget constraints.

Fisheries crackdown pushes Cambodians to the brink on Tonle Sap lake
- A ban on illegal fishing in Tonle Sap, Cambodia’s largest lake, is hitting local communities hard — even those engaged in legal fishing.
- “By continuing to fish, we are forced into hiding, we are forced into crime,” one fisher told Mongabay, describing a climate of fear amid a heavy law enforcement presence.
- Another says the crackdown is being prosecuted with impunity: officers “will confiscate anything from anyone and then say ‘It’s illegal’” in an alleged ploy to solicit a bribe.
- This story was supported by the Pulitzer Center’s Rainforest Investigations Network where Gerald Flynn is a fellow.

Farmers feel the pressure after conservation crackdown around Cambodia’s Tonle Sap Lake
- Cambodia’s Tonle Sap Lake is surrounded by a conservation area that consists of three zones: Zone 1 and 2, where farming is allowed, and Zone 3, which is closest to the lake and where agriculture and fishing are officially banned.
- The conservation area was enacted in 2011, but farmers and fishers largely had unfettered use of Zone 3 land until 2021, when Prime Minister Hun Sen ordered a crackdown on all clearing and agricultural use of flooded forest land.
- The ban opens an opportunity for the government to restore Tonle Sap’s unique forests, and satellite data already show a drop in deforestation activity in 2022.
- However, farmers living around the lake say they’re hard-pressed to survive without the agriculture they’ve depended on for years.

Overexploitation threatens Amazon fisheries with collapse, study warns
- Fishers in the Amazon Basin are catching smaller species of fish than before, indicating overexploitation of the region’s aquatic biodiversity, a new study says.
- The study looked at fish catch data from six river ports (three each in Peru and Brazil) to conclude that “fisheries are losing their resilience and progressing towards possible collapse.”
- Researchers say freshwater fish stocks in the Amazon have never been a priority for conservation or monitoring, which has allowed this decline to occur over the course of decades.
- The loss of larger fish deprives communities for whom fish is a dietary staple of important nutrients, as well as impoverishes the wider river ecosystem.

In restoring polluted rivers, Indonesia looks at restocking endemic fish
- Two reported mudflows overflowed the Serayu River on the Indonesian island of Java within the space of a week earlier this year, mucking its waters and killing off fish.
- The incidents have raised calls from conservationists and fishers for restoration and fish restocking efforts in the river.
- Fish restocking has been carried out for several decades in Indonesian rivers, mainly as an effort to increase fisheries productivity and fish populations in inland waters such as rivers, reservoirs and lakes.
- But experts say these restocking efforts often emphasize ceremony at the expense of measures to ensure success, such as post-monitoring assessment.

Giant stingray caught in Cambodia is world’s largest freshwater fish
- The largest freshwater fish ever recorded was captured last week in Cambodia’s stretch of the Mekong River: a giant freshwater stingray measuring 4 meters (13 feet) from snout to tail and weighing 300 kilograms (661 pounds).
- The discovery occurred in a stretch of the Mekong known for its diversity of freshwater habitats that support crucial fish-spawning grounds and migration corridors and provide refuges for other mega fish species and threatened species, such as Irrawaddy dolphins and giant softshell turtles.
- Local fishers collaborating with researchers to document the area’s underwater life alerted a monitoring team who measured the ray, fitted it with an acoustic tag to learn more about its behavior, and facilitated its release back into the wild.
- Experts say the find emphasizes what’s at stake in the Mekong, a river that’s facing a slew of development threats, including major hydropower dams that have altered the river’s natural flow. “It is a signal to us to protect our rivers and lakes,” they say.

A tale of successes and new challenges in Senegal: Q&A with ICCA coordinator Salatou Sambou
- The Kawawana conserved area (ICCA) was created by a group of Indigenous Jola fishers in Casamance. After almost ten years, they have succeeded in restoring an area where biodiversity had all but disappeared.
- Now that biodiversity and resources have recovered, life in the village has become more secure. The model’s success has also encouraged young people to return and to renew their commitment to its conservation.
- But the ICCA has also come up against many challenges, such as the COVID-19 pandemic, state indifference to poachers and climate change, since Mongabay’s last reporting in 2018.
- Mongabay interviewed Salatou Sambou, ICCA coordinator involved in the Kawawana conserved area, about the recent successes and challenges the ICCA is facing.

First gharial hatchlings spotted in nearly two decades in Nepal’s Karnali River
- Twenty-eight gharial hatchlings have been spotted in a tributary of Nepal’s Karnali River, the first sign of successful nesting in this waterway in at least 16 years.
- The discovery by villagers living near Bardiya National Park came on June 15, two days before World Crocodile Day, and indicates the critically endangered species is on the road to recovery.
- Nepal is home to about 200 breeding gharials, and since 1978 has carried out conservation and breeding programs for the species.

For Thai fishers facing dwindling catches, a Lao dam looms large
- Laos plans to build a $2 billion, 684-megawatt dam on the Mekong River, just 2 kilometers (1.25 miles) from the Thai border.
- The proposed Sanakham dam is the latest in a cascade of more than a dozen dams operating on the Mekong mainstream in China and Laos.
- Fishers in Thailand say they’ve already seen their catches decimated with each new dam built upstream, in particular the Xayaburi dam that went online in Laos in 2019.
- The Sanakham project is still in a “prior consultation” process with the Mekong River Commission, an advisory intergovernmental agency.

In the Mekong’s murky depths, giants abound, new expedition finds
- An underwater expedition into the deepest pools in the Mekong River has confirmed the presence of giant freshwater fish, fish migration routes, and high volumes of discarded fishing gear and plastic waste.
- The international team of underwater explorers, local fish biologists and fishermen used deep-sea camera technology to document the ecological value of the unique area in northeastern Cambodia, which is characterized by 80-meter-deep (260-foot) pools, flooded forests and braided river channels.
- But just as researchers reveal the value of its biodiversity, food security and fisheries livelihoods, the area faces a new threat: earlier this year, feasibility surveys began for a hydropower dam planned for directly upstream of the deep-pool habitats.
- According to the expedition team, construction of the Stung Treng dam would have “devastating ecological effects and could seriously threaten local food security in an area of the world already impacted by changing climate.”

Boom and bust on Lake Victoria: Q&A with author Mark Weston
- In a new book, British author Mark Weston examines an environmental crisis on East Africa’s Lake Victoria that’s been a century in the making and stems from the introduction of the non-native Nile perch to the lake in the 1950s.
- Weston lived on Ukerewe, the lake’s largest island, for two years, and relates the knock-on legacy of the fish’s introduction through the experiences of the people he met there.
- The boom and bust of the fishery brought about a surging population, deforestation, declining land fertility, and increased pollution in the lake.
- With Nile perch catches down precipitously and little else to sustain the economy of Ukerewe, residents struggle through poverty, lack of opportunity and a trickling exodus from the once-prosperous community, in search of a better life for themselves and their families.

The world’s dams: Doing major harm but a manageable problem?
- Dam construction is one of the oldest, most preferred tools to manage freshwater for various uses. The practice reached a peak internationally in the 1960s and ’70s, but in recent years dam construction has faced increasing global criticism as the hefty environmental price paid for their benefits piles up.
- The flows of most major waterways have been impacted by dams globally. Only 37% of rivers longer than 1,000 km (620 mi) remain free-flowing, and just 23% flow uninterrupted to the sea. Natural flows will be altered for 93% of river volume worldwide by 2030, if all planned and ongoing hydropower construction goes ahead.
- This global fragmentation of rivers has led to severe impacts. Dams have contributed to an 84% average decline in freshwater wildlife population sizes since 1970. More than a quarter of Earth’s land-to-ocean sediment flux is trapped behind dams. Dams also impact Earth’s climate in complex ways via modification of the carbon cycle.
- But dams are needed for energy, agriculture and drinking water, and are an inevitable part of our future. Lessons on how to balance their benefits against the environmental harm they do are already available to us: removing some existing dams, for example, and not building others.

GM fish engineered to glow in the dark are found in Brazil creeks
- A recent study shows that genetically modified zebrafish, known as GloFish, have been found and are breeding in creeks in Brazil’s Atlantic Forest.
- GloFish, which are genetically engineered for fluorescence, are advertised for sale online in Brazil, even though they’ve been banned there since 2017.
- Brazilian biologists have called for measures to prevent these fish from escaping fish farms and entering into local bodies of water, where they compete with native species for food.
- But a U.S biologist whose own research showed that GloFish fail to compete reproductively against wild-type zebrafish says this new paper is “almost a study about nothing” and was published only because it was “sensational.”

Cambodian project aims to revive flagging fish populations in Tonle Sap Lake
- Struggling freshwater fish populations in the Mekong River catchment received a boost earlier this month when a team of scientists and fisheries specialists released 1,500 captive-reared juvenile fish into Tonle Sap Lake in Cambodia.
- Experts say the release is the first step in rejuvenating the Mekong’s depleted fish populations and fisheries, which have been suffering in recent years due to overfishing, drought, habitat destruction, and the impacts of upstream dams on the Mekong River’s natural flow.
- The fish, including critically endangered Mekong giant catfish and giant barb, and endangered striped river catfish, were released into a series of fish sanctuaries and community conservation areas that protect crucial fish nursery habitat in Tonle Sap Lake, the world’s most productive inland fishery.
- Long-term survival of the Mekong’s threatened fish species will also depend on protection of migration corridors and upstream spawning grounds, and on maintenance of free-flowing and connected watercourses, say experts.

Pharmaceutical water pollution detected deep in the Brazilian Amazon
- Major rivers in the Amazon Basin of Brazil are contaminated with a wide range of pharmaceuticals as well as with sewage and wastewater, largely coming from urban centers in the region, according to recent research.
- Water samples taken along the Amazon, Negro, Tapajós and Tocantins rivers, and small urban tributaries that pass through the region’s cities, including Manaus, Santarém, Belém and Macapá contained 40 pharmaceuticals out of 43 in concentrations that have the potential to affect 50-80% of the local aquatic species.
- Experts explain that a major cause of freshwater contamination is the Amazon Basin’s rapidly growing population along with the government’s failure to provide adequate sanitation infrastructure — even though that has long been promised. Most of the region’s sewage is untreated, a solvable problem if properly funded.

Threatened wetlands in Paraguay’s Lake Ypacaraí raise legal questions
- Wetlands surrounding the protected Lake Ypacaraí in Paraguay are being filled in to allow for the construction of housing and tourism projects.
- In addition to providing habitats for countless species of flora and fauna, the wetlands act as a filter for freshwater and help control flooding and erosion.
- The projects were approved by the Ministry of Environment, sparking outcry from congressmen who want to know if protected area laws are being ignored in favor of urban development.

One fish, two fish: New goby species described from the Philippines
- Scientists recently described two new-to-science species of freshwater fish from the Philippine island of Palawan: Rhinogobius estrellae and Rhinogobius tandikan.
- The tiny, blue-spotted fish are endemic to Palawan and each is confined to freshwater pools and streams in a single location.
- The fish were collected during surveys to document freshwater fish diversity on the island; both species belong to a genus previously only known from temperate and subtropical parts of Asia, with the new discovery extending its range south into the tropics.
- Due to their restricted range, the fish are deemed highly threatened and their habitats in need of safeguards against mining, road construction and invasive species.

Alaskan Indigenous leaders fear impacts on salmon streams by mining project
- Mining company Donlin Gold is seeking to develop one of the world’s largest open-pit gold mines near Alaska’s Kuskokwim River, a spawning ground for several species of salmon, which make up 50 percent of local communities’ diet and subsistence lifestyle.
- According to Donlin Gold, Native corporations have already approved of the mine and the best available technology will be utilized to meet or exceed all air and water quality standards while providing employment opportunities.
- Tribal leaders argue Native corporations agreed without consulting tribal governments, who are shareholders, and fear mercury contamination and the disruption of their access to hunting and fishing grounds, as underlined in the project’s Environmental Impact Statement.
- Tribal councils have brought the matter to the Alaska Superior court and are appealing two certifications necessary for construction due to exceeded levels of mercury and impacts to salmon streams.

Indonesia aims for sustainable fish farming with ‘aquaculture villages’
- Indonesia plans to have a network of 136 villages dedicated to aquaculture by the end of this year.
- The initiative is part of the government’s efforts to boost exports of its world-renowned aquaculture commodities, namely shrimp, lobster, crab and seaweed.
- Experts have welcomed the plan, but say it must be supported by sound environmental planning, particularly avoiding the clearing of mangrove forests and ensuring proper waste management.
- Indonesia is one of the top exporters of farmed seafood, but fish farming in the country has long come at the expense of carbon-rich mangrove forests and other important coastal ecosystems.

Holy loach! Fish missing for decades rediscovered in Turkey’s Batman River
- Researchers in Turkey recently rediscovered the Batman River loach, a species that hadn’t been seen since 1974.
- There have been many prior unsuccessful attempts to find the species, leading to speculation that it may have gone extinct.
- While very little is known about the species, experts believe that it was impacted by the construction of the Batman dam.
- The scientists found the species in a part of the river that’s upstream of the dam.

In southern Colombia, Indigenous groups fish and farm with the floods
- The Tikuna, Cocama and Yagua peoples in southern Colombia live on a two-pronged sustainable food system that involves artisanal fishing and communal planting synchronized with the different flooding seasons.
- The food systems have allowed the 22 communities in the area to live sustainably without damaging the forest’s extremely high rates of biodiversity, according to a report from the U.N.’s Food and Agriculture Organization (FAO).
- The communities have faced some challenges in recent decades due to outside pressures to commercialize their activities, raising doubts about how to maintain sustainable practices.
- This article is part of an eight-part series showcasing sustainable food systems covered in the most comprehensive report to date of the diets and food production practices of Indigenous peoples and local communities (IPLCs).

Amazon dams: No clean water, fish dying, then the pandemic came
- Villagers living near the Teles Pires and São Manoel dams in Brazil’s Mato Grosso state — including the Apiaká, Kayabí and Munduruku peoples — attest to poor water quality, lack of potable water, increased malaria and rashes since the dams were built on their river. They also say there has been little response from the dam companies.
- Indigenous peoples say the Brazilian hydroelectric projects have altered river ecology along with thousands of years of cultural practice, especially their fishing livelihood. Migratory fish and other game fish have been greatly diminished, so residents must now resort to fishing at night.
- Once the COVID-19 pandemic arrived in the region, lack of clean water for bathing became even more urgent, while disappearing fish in daily diets made it harder to get food or isolate in riverside villages. Only under judicial order did dam companies recently improve water supply infrastructure.
- Experts trace these adverse impacts back to the dams’ planning stages: with the construction companies skipping legally mandated steps, not consulting Indigenous peoples as required, and failing to calculate cumulative impacts of multiple dam projects. Villagers are now monitoring impacts — and some are studying the law.

Declining fish biodiversity in Peruvian Amazon affecting human nutrition
- Declining fish diversity in the Peruvian Amazon could affect nutrition for many of the region’s 800,000 people, according to a new study.
- In Loreto region, fishers have been catching fewer large migratory fish species, which are being replaced by smaller fish. Although protein levels are roughly the same, smaller fish contain more omega-3 fatty acids but less iron and zinc, overall—an issue in a region where people already have high rates of anemia and malnutrition.
- Inland communities are already transitioning toward eating more farmed fish and chicken, but these foods may not be an adequate replacement for the range of nutrients these communities get from a diverse diet of wild fish.
- Although this study focused on regional fish, other wild foods such as plants, insects and bushmeat are an important source of nutrition across the globe. Therefore, policies and practices that preserve biodiversity are not only important for conservation but also a means towards greater food security and public health.

Genetic diversity of Sri Lanka’s ‘spa fish’ highlights need for informed conservation
- An endemic freshwater fish species known as the “stone sucker” (Garra ceylonensis) has six genetically different populations spread in different river basins in Sri Lanka despite managing to sport similar looks, a new study shows.
- The research estimates that the ancestor of G. ceylonensis first colonized Sri Lanka around 3 million to 4 million years ago via rivers on the land bridge between India and Sri Lanka and that subsequent climatic events trapped them on the island, causing the fish to evolve as a distinct species along with genetic variances.
- The study highlights the need for innovative efforts in conserving genetically distinct populations, going beyond a mere species-level focus to conserve Sri Lanka’s rich biodiversity.
- G. ceylonensis, also known as the “doctor fish,” is part of a popular group of fishes used in the foot spa industry to nibble off dead skin, driving an increase in wild collections for the aquarium trade.

Outrage as Cambodian court convicts activists for inciting ‘social chaos’
- On May 5, the Phnom Penh Municipal Court convicted and sentenced five activists from the environmental group Mother Nature Cambodia: Long Kunthea, Phuon Keoraksmey, Thun Ratha, Chea Kunthin and Alejandro Gonzalez-Davidson.
- The activists have been convicted of intending to cause “social chaos” by planning a protest of the government-sanctioned destruction of Phnom Penh’s lakes, which are being filled in for development. The planned one-person march never actually took place.
- Kunthea and Keoraksmey were sentenced to 18 months in prison and Ratha received a 20-month sentence while Alejandro Gonzalez-Davidson and Chea Kunthin were sentenced in absentia; each activist was also fined $1,000.
- Observers are crying foul at the convictions and incarceration of the activists and say that the health and lives of Kunthea, Keoraksmey and Ratha – who have been incarcerated since their arrest in September – are at risk due to Cambodia’s crowded prisons and a recent surge in COVID-19 infection rates.

An Amazonian arapaima washed up in a Florida river. It didn’t swim there
- In February, Florida officials identified the body of an arapaima (Arapaima gigas) that had washed ashore from the Caloosahatchee River.
- An expert said the arapaima, a fish species endemic to the Amazon lowlands, had likely come from the pet trade.
- Live arapaimas are mainly brought into the U.S. for aquaculture, although a small number are also imported for the pet trade, another expert said.
- While arapaimas are not currently considered to be an invasive species, there are concerns they could become problematic in the future if enough end up in Florida’s waterways.

Amazon’s Belo Monte dam cuts Xingu River flow 85%; a crime, Indigenous say
- In February, IBAMA, Brazil’s environmental agency permitted Belo Monte mega-dam operator Norte Energia to drastically reduce flows to the Volta Grande (Big Bend) of the Xingu River for at least a year. That decision reversed an earlier ruling to maintain much higher Xingu River flows and the fishery — as legally required.
- The flow reduction will leave 70% of usually-flooded forest dry this season, causing massive fish mortality and diminished reproduction, experts say. Community group Xingu Vivo Para Sempre denounced the decision as “a death sentence for the Xingu” and demanded IBAMA’s and Norte Energia’s presidents be “criminally prosecuted.”
- Norte Energia has funded projects to mitigate the reduced flow, collecting and dropping fruit into the river for fish to feed on, and releasing captive-bred fish. But scientists say these approaches are unscientific and will likely be ineffective, and can’t make up for the loss of the river’s seasonal flood pulse, upon which fish depend.
- Residents say the government has spread misinformation, telling Brazilian consumers that their electricity bills would go up if Belo Monte released more water to maintain the Xingu’s ecosystem — something Norte Energia is obligated to do. At present, water levels on the Volta Grande have not been restored.

Calls for accountability after coal-slurry spill in Indonesian river
- A coal-slurry spill into a river in Indonesian Borneo has killed hundreds of fish and forced authorities to shut off water lines to households.
- The slurry came from a waste facility run by coal miner PT Kayan Putra Utama Coal, which has apologized for the Feb. 7 incident and promised to distribute clean water to affected residents.
- Industry watchdogs and residents say such incidents are common on the Malinau River in North Kalimantan province, where coal mining is a major industry.
- The provincial legislature has called for an investigation and criminal charges if necessary against the company.

Belo Monte dam’s water demands imperil Amazon communities, environment
- Norte Energia, the builder and operator of the controversial Belo Monte mega-dam is pushing for implementation of a much disputed “consensus hydrogram” — a plan to annually manipulate water releases into the Xingu River’s Volta Grande (Big Bend), with estimated peak April releases ranging from a mere 4,000 – 8,000 m3/s.
- Noting that April average historical river flows in the Volta Grande before the dam was built were 19,985 m3/s, analysts say this dearth of water flow will prevent and imperil annual fish reproduction. One Volta Grande expert estimates that, using the so-called consensus hydrogram plan, at least 80% of Volta Grande fish will die.
- Documents from IBAMA, Brazil’s environmental agency, which first came to light publicly on December 3, acknowledge “grave and irreparable impacts” from the Belo Monte dam, and signal an urgent need to revise Norte Energia’s planned consensus hydrogram.
- Two recent studies say fish are decreasing dramatically in diets within Belo Monte’s influence area, causing food insecurity. Norte Energia claims fish quantities sold locally remain the same, but their data may mask significantly increased fishing effort, and the need to fish more widely, beyond previous fishing areas.

A Malagasy community wins global recognition for saving its lake
- A community association charged with managing Lake Andranobe in central Madagascar has won this year’s Equator Prize from the UNDP in the category “Nature for Water.”
- The association’s efforts, including implementing fishery closures, regulating water use, and reforestation, have led to increased fish catches and helped revive the lake ecosystem.
- As in the rest of the world, Madagascar’s wetlands are often overlooked in conservation priorities, despite the fact that freshwater species are even more threatened than terrestrial or marine biodiversity.
- The prize highlights the benefits of community-driven management, which often works better than initiatives undertaken by outsiders but also carries considerable challenges.

Why the health of the Amazon River matters to us all: An interview with Michael Goulding
- Like the rainforest which takes its name, the Amazon is the largest and most biodiverse river on the planet. The river and its tributaries are a critical thoroughfare for an area the size of the continental United States and function as a key source of food and livelihoods for millions of people. Yet despite its vastness and importance, the mighty Amazon is looking increasingly vulnerable due to human activities.
- Few people understand more about the Amazon’s ecology and the wider role it plays across the South American continent than Michael Goulding, an aquatic ecologist at the Wildlife Conservation Society (WCS) who has worked in the region since the 1970s studying issues ranging from the impact of hydroelectric dams to the epic migration of goliath catfishes. Goulding has written and co-authored some of the most definitive books and papers on the river, its resident species, and its ecological function.
- In recognition of his lifetime of advancing conservation efforts in the Amazon, the Field Museum today honored Goulding with the Parker/Gentry Award. The Award — named after ornithologist Theodore A. Parker III and botanist Alwyn Gentry who were killed in a plane crash during an aerial survey of an Ecuadorian cloud forest in 1993 — is given each year to “an outstanding individual, team or organization in the field of conservation biology whose efforts have had a significant impact on preserving the world’s natural heritage and whose actions and approach can serve as a model to others.”
- In a September 2020 interview ahead of the prize ceremony, Goulding spoke with Mongabay about his research and the current state of the Amazon.

Mercury from gold mining contaminates Amazon communities’ staple fish
- The four species of fish most commonly consumed by Indigenous and riverine people in the Brazilian state of Amapá contain the highest concentrations of mercury.
- In some species, researchers found levels of mercury four times in excess of World Health Organization recommendations.
- The mercury comes from gold-mining activity, where it’s used to separate gold from ore before being burned off and washed into the rivers.
- The health impacts of mercury contamination are well-documented, and include damage to the central nervous system, potentially resulting in learning disabilities for children and tremors and difficulty walking for adults.

Fishing for change: Local management of Amazon’s largest fish also empowers women
- High market demand led to declining numbers and a ban on arapaima fishing in the late 1990s, though illegal poaching for the black market continued.
- According to a recent paper, the co-management system that has helped these fish recover also provides new opportunities for women in fishing communities.
- Women working in co-management have newly independent incomes and receive previously unknown respect for their roles, though further work is needed to cement these gains.

More than 500 dams planned inside protected areas: Study
- More than 500 dams are either under construction or planned within protected areas over the next two decades, according to a new study.
- The study found that more than 1,200 large dams already exist within protected areas.
- The authors strongly encourage governments to avoid constructing dams in or near protected areas and instead to look toward renewable energies such as wind and solar.
- The researchers express concerns about ongoing rollbacks to environmental protections, especially amid the COVID-19 pandemic.

New assessment shows 74% of Sri Lanka’s freshwater fish threatened with extinction
- A recent conservation assessment of Sri Lanka’s freshwater fish has come up with a total of 139 species, of which 61 are found nowhere else on Earth.
- The new assessment showed that 74% of endemic freshwater fish are threatened with extinction: 12 are critically endangered, 24 endangered, and nine vulnerable.
- Many of Sri Lanka’s freshwater fish groups have undergone significant changes and the new study sheds much needed light on their taxonomic diversity.
- Most of Sri Lanka’s freshwater fish are found outside protected areas and are thus affected directly by all the major drivers of biodiversity loss such as habitat loss and degradation, overexploitation, pollution, invasive alien species, and climate change.

Migratory freshwater fish in peril as report shows population plunge
- A new report finds that migratory freshwater fish species have declined on a global scale by 76% since 1970, with the highest drops experienced in Europe.
- The biggest threat to migratory freshwater fish is habitat degradation or alteration, such as dams, culverts and road crossings, while other threats include habitat loss, overfishing, pollution, and climate change.
- The authors of the report recommend taking actions to help restore migratory freshwater fish populations, including the restoration of free-flowing rivers by removing dams and other obstructions.

In Sri Lanka, the hunt is on for alien fish in native lakes
- A young fish enthusiast from suburban Sri Lanka is on a personal mission to remove invasive species from the island’s lakes and other waterways, starting with clown knifefish and alligator gars introduced as part of the aquarium fish trade.
- Sri Lanka’s freshwater habitats are plagued by at least 30 exotic fish species, according to the most recent assessment — either released intentionally for aquaculture or mosquito control, or accidentally through the aquarium trade — with a number of them having turned invasive.
- Some of the carnivorous species are listed among the world’s worst invasive fish, including the knifefish, which has become established in a number of key habitats and poses a threat to native freshwater species, many of which are endemic.
- Experts have called for stronger regulation to prevent the continued introduction of alien invasive fish species into Sri Lanka’s freshwater habitats.

Amazon poor go hungry as Brazil slashes social safety net, cuts forests: Study
- Living along the rivers of the Amazon rainforest, many imagine, would make for a sustainable diet packed full of freshwater fish. But a recent study finds this is not the case. A combination of interacting factors is now causing many poor families in riverine communities to go hungry.
- Researchers found that Amazon fish catch rates are naturally 73% lower in the highwater season. In the past, this lull was supplemented by hunting. But Brazilian deforestation, increased under former Pres. Michel Temer and now under Pres. Jair Bolsonaro, has replaced biodiverse forests with soy and other kinds of plantations.
- Add to this Bolsonaro’s and Temer’s rapid deconstruction of internationally-lauded social welfare programs, implemented by Presidents Lula and Rousseff and their Workers’ Party, which fed many riverine families when fish catches dropped.
- Figure in climate change too: its deep droughts harm forest and river diversity, while extreme floods keep stream levels high and fish catches low, and for longer. Now, COVID-19 has come to the Amazon, with food shopping trips made from rural riverine settlements to cities now requiring a serious element of risk.

Communities on Brazil’s ‘River of Unity’ tested by dams, climate change
- The Pixaim Quilombo is one of many traditional communities made up mostly of Afro-Brazilian descendants of runaway slaves. It sits at the mouth of the São Francisco River, one of Brazil’s most important waterways.
- Once a thriving community, it has been struggling for decades due to the impacts of upriver dams which reduce the river’s flow and alter aquatic migrations. As a result, one of the community’s two chief livelihoods has been sharply curtailed — the river’s fishery is in steep decline.
- Now, climate change threatens to make those struggles even greater, further changing fish populations, reducing river flow even more, and dangerously elevating the salinity of the stream as seawater intrudes. Rice, which once provided Paixim’s second major livelihood, can no longer be grown in the delta’s saltier marshes.
- Pixaim is seeing a major outmigration as subsistence livelihoods becomes more difficult. Residents there count among 18 million people residing in the São Francisco River watershed, impacted by a steadily dwindling water resource.

Past and future tropical dams devastating to fish the world over: Study
- Most research on the ecological impacts of tropical dams does so one dam project at a time. But a new landmark study attempts to connect the dots globally by analyzing tropical dam impacts on freshwater river fish around the world.
- The research assembled data on the geographic range of 10,000 fish species, and checked those tropical species against the location of 40,000 existing dams and 3,700 dams that are either being built or planned for the near future.
- Scientists found that biodiversity hotspots including the Amazon, Congo, Salween and Mekong watersheds are likely to be hard hit, with river fragmentation potentially averaging between 25% and 40% due to hydropower expansion underway in the tropics.
- Dams harm fish ecology via river fragmentation, species migration prevention, reservoir and downstream deoxygenation, seasonal flow disruption, and blockage of nurturing sediments. Drastic sudden fish losses due to dams can also destroy the commercial and subsistence livelihoods of indigenous and traditional peoples.

Extinction of a megafish: Can this spark action to save other migratory freshwater species? (commentary)
- The Chinese paddlefish, recently declared extinct by researchers, was likely the world’s longest freshwater fish – as well as one of the oldest, swimming the earth’s rivers since the time of the dinosaurs.
- It’s too late for this species, but there’s still time to save many of the world’s remaining migratory fish.
- Parties to the Convention on Migratory Species – who will meet in Gandhinagar, India, from February 15 to 22 – must address the growing threats to migratory freshwater fish, argues William Darwall, Head of the Freshwater Biodiversity Unit, IUCN Global Species Programme.
- This post is a commentary. The views expressed are those of the author, not necessarily Mongabay.

The long goodbye: Study declares ancient Chinese paddlefish extinct
- The Chinese paddlefish (Psephurus gladius) was last recorded by researchers in 2003. Subsequent local surveys failed to spot any individual.
- A new study based on a comprehensive large-scale survey in 2017 and 2018 and statistical analysis of previous records suggest that the species most likely went functionally extinct by 1993 and completely extinct by 2010.
- There’s always the possibility that individuals of a species declared extinct still survive somewhere, but in the case of the Chinese paddlefish that’s highly unlikely, researchers say.
- The factors that contributed to the paddlefish’s extinction, including the construction of a dam that split its population, also threaten other species unique to the Yangtze River basin.

Shocking news: There are actually three species of electric eel in the Amazon, not one
- A mostly nocturnal species found in freshwater habitats in Mexico and South America, the electric eel (Electrophorus electricus) belongs to the knifefish family and is more closely related to catfish and carp than other eels. It was first described more than 250 years ago by Swedish naturalist Carl Linnaeus.
- But now a team of scientists led by Carlos David de Santana, an associate researcher at the US Smithsonian National Museum of Natural History, has determined that E. electricus is in fact three distinct species.
- During their work in the field, the researchers used a voltmeter to record a member of one of the newly described species, E. voltai, discharging 860 volts, the highest discharge ever recorded for any animal (the previous record was 650 volts).

Two-thirds of Earth’s longest rivers no longer free-flowing
- Just one-third of the planet’s 242 longest rivers still flow uninterrupted along their entire length, most of them located in remote regions of the Arctic, the Amazon Basin, and the Congo Basin, according to a study to be published in Nature tomorrow.
- The international team of researchers behind the study, led by Günther Grill of Canada’s McGill University, determined that, of the 91 rivers longer than 1,000 kilometers (about 600 miles) that once emptied out into an ocean, only 21 are still unobstructed from their source to the sea.
- Dams and associated reservoirs are the biggest causes of river obstruction, the researchers say. There are nearly 60,000 large dams in the world already, and as many as 3,700 more large hydroelectric dams are currently in the planning stages or under construction.
- Healthy rivers provide a number of benefits to mankind, from recreation to food security. Ensuring the connectivity of the world’s remaining free-flowing rivers is also critical if we’re to preserve biodiversity in freshwater systems.

Madeira River dams may spell doom for Amazon’s marathon catfish: Studies
- Independent monitoring of a giant Amazon catfish population in the Madeira River, a major tributary of the Amazon, confirms that two hydroelectric dams have virtually blocked the species’ homing migration upstream — the longest known freshwater fish migration in the world.
- Research completed in 2018 indicates a serious decline in catches of the gilded catfish (Brachyplatystoma rousseauxii) and other key commercial species on the Madeira, both upstream and downstream of the two dams.
- New monitoring techniques show that the disruption of the migration route raises the risk of extinction for this species, for which researchers have recommended the conservation status be elevated from vulnerable to critically endangered.
- If the gilded catfish and other migratory species are to survive, mechanisms to assist their migration past the dams must be improved, researchers say.

Freshwater fishes and other threatened but overlooked biodiversity must be new flagships for conservation (commentary)
- Today there are believed to be at least 15,000 species of freshwater fishes. Only 54 percent of them have been assessed under the IUCN Red List, and one-third of these species are considered to be under threat of extinction. For the many species that remain unassessed, or for which there is too little information to make an assessment, the situation is likely to be as bad or worse.
- While there is so much to do, there are only a handful of dedicated freshwater fish conservation organizations, and few have full-time staff. Trout and salmon have received large amounts of attention and, as a consequence, there are many stories of conservation success. There are fewer stories of success for species outside North America and northern Europe. And this is what we will change with Shoal.
- The call by leading conservation agencies for a “new deal for nature” at the next Conference of the Parties of the Convention for Biological Diversity in 2020 needs to be firmly founded on neglected species, particularly freshwater biodiversity. Shoal will engage thousands of people and businesses across the globe who share a love of and stake in the future of freshwater species and healthy, productive wetlands but until now have had little opportunity to engage in the more mainstream conservation movement.
- This post is a commentary. The views expressed are those of the author, not necessarily Mongabay.

Ecuador’s indigenous Cofán hail court-ordered end to mining on their land
- A court in Ecuador’s Sucumbíos province has ordered that the mining concessions already in operation on territory claimed by the Cofán indigenous people, and those currently in the process of being granted, must be canceled, affecting some 324 square kilometers (125 square miles) in total.
- The ruling also requires that reparations be made for any impacts caused by recent mining.
- For the community, the court’s decision is a victory that represents a milestone for the rights of all indigenous communities in Ecuador.

Indonesian fish farmers get early-warning system for lake pollution
- In the wake of the latest mass fish death in Indonesia’s Lake Toba, in northern Sumatra, the government has published a predictive calendar that gives fish farmers early warning of dire water conditions.
- The tool, available online and in printed form, ranks conditions on a progressive scale running from “safe” to “alert” to “dangerous.”
- In addition to the calendar, the government has also recommended other solutions, including the growing of water hyacinths to absorb pollutants in the lake, and reforestation efforts in the area.

‘Diaper Brigade’ fights a chemical crisis in Java’s rivers
- Indonesian biologist Prigi Arisandi leads a movement to tackle the dumping of millions of disposable diapers into rivers across Indonesia’s Java Island every year.
- Used diapers contain a long list of chemical components that don’t degrade easily, contaminating river ecosystems.
- Fishing the diapers from the rivers is a quick solution. Over the long term, Prigi says, governments and diaper manufacturers must establish better waste management policies, and consumers must cut back on their use of disposable diapers.

‘Shocking and worrying’: Selective logging has big, lasting impact on fish
- A new study finds nearly as few fish species in selectively logged forests as they did in forests clear-cut for plantations. Both selectively logged and clear-cut areas had around half the number fish species present in protected, intact forests.
- These findings run counter to conventional wisdom that holds selective logging is not as ecologically destructive as complete deforestation.
- The study also found a similar number of fish species in streams in oil palm plantations with and without remnant forest buffers, which are often mandated in the hopes of safeguarding biodiversity.
- The study’s authors say their findings underline the importance of protecting remaining primary forest.

Fish tales: Six amazing journeys to celebrate World Fish Migration Day
- April 21 marks World Fish Migration Day, a biennial event that strives to foster appreciation for the importance of migratory fish and their aquatic swimways.
- Healthy fish stocks with unimpeded migrations are essential to feeding humankind and maintaining the ecological equilibrium of the world’s waters.
- But fish migrations are being increasingly stressed by a worldwide boom in the building of dams that block their essential riverine passage, pollution, overfishing, lowering of water levels for agriculture and drinking water, and climate change.
- Here are six notable fish migrations to consider on this day.

In Bali fish die-offs, researchers spot a human hand
- Mass fish die-offs are not uncommon in the volcanic lakes that dot Indonesia, including Bali’s Lake Batur, which sits in the crater of an active volcano.
- While sulfur releases, steep temperature gradients and other natural phenomena are responsible for some of the bigger die-offs, researchers have identified the chemicals from excess fish feed as the main culprit for the more frequent die-offs caused by oxygen depletion.
- Similar die-offs in other lakes around Indonesia have also been traced back to household and industrial waste, as well as agricultural runoff and fish farms. Researchers have warned that more than a dozen lakes could die out as soon as 2025 as a result of this chemical assault.

More than 40 percent of Madagascar’s freshwater life sliding toward extinction, IUCN finds
- In an assessment of 653 freshwater plant and animal species living on Madagascar and nearby islands, biologists found that 43 percent are threatened with extinction or there isn’t enough information to assess how well they’re doing.
- Nearly 80 percent of endemic plants examined in the study face extinction.
- The team lists unsustainable farming practices, deforestation, dam construction, mining and the overuse of natural resources, such as overfishing, as causes for the widespread declines.

Forest Code falls short in protecting Amazonian fish
- A team of scientists reports that Brazil’s Forest Code doesn’t address significant impacts that agriculture can have on fish habitat in the rainforest’s streams and tributaries.
- The study cataloged more than 130 species of fish, some of them new to science, in Brazil’s eastern Amazon.
- The authors argue for protections that encompass entire basins and the complex drainage networks that together form the lifeblood of the Amazon rainforest.

As Northwest salmon economy teeters on brink, Trump gives it a push
- Northwest salmon fisheries are in trouble, impacted by warming oceans and overdeveloped, dammed and silted spawning rivers and streams.
- Pre-contact indigenous groups in the region once organized their societies around sustainable fishing tribal agreements that worked. More recently, under past presidential administrations, Canadian, US and tribal authorities came together to save the declining salmon fisheries.
- Especially successful have been federally funded local, state and tribal programs, administered by NOAA, that protect and restore Northwest spawning streams — an investment in habitat and healthy local economies.
- Trump’s 2018 budget would cut all those programs, though for now Congress has restored them. However, politicians and regulators are concerned that Trump’s abandonment of Northwest fisheries and local economies will persist through his administration.

Extinction in the wild looms for two California fish (commentary)
- The delta smelt is a three-to-four-inch long, silvery-blue fish that has long been at the center of California’s contentious water wars.
- The species lives only in the San Francisco Bay and the Sacramento-San Joaquin Delta, and its numbers have been declining for decades as enormous quantities of freshwater are diverted through the state’s vast network of aqueducts and canals.
- The freshwater river flow also replenished Chinook salmon spawning grounds and freshened habitats (reducing salinity) in San Francisco Bay for waterfowl, Dungeness crab, and countless other aquatic flora and fauna in an immense system of sloughs, mudflats, and marshes. Now, however, most of that water is diverted to California’s thirsty farms and clamoring, growing cities.
- This post is a commentary. The views expressed are those of the author, not necessarily Mongabay.

Mountain streams in the U.S. show surprising resilience to climate change
- A newly published study in the Proceedings of the National Academy of Sciences reveals that certain ecosystems may be more resistant to warming temperatures than previously thought.
- The study focused on how rates of temperature change in mountain streams, which the researchers call “stream climate velocities,” may affect cold-water species that have been deemed vulnerable or threatened according to IUCN criteria.
- The study concludes that the results give “hope that many native species dependent on cold water can persist this century and mountain landscapes will play an important role in that preservation.”

Tapajós dams may bring fish kills, species loss, mercury contamination
- Brazil plans to construct seven hydroelectric dams on the Tapajós River and its tributaries — a part of the Amazon known for its exceptional aquatic and terrestrial biodiversity. The São Luiz do Tapajós hydropower plant is the largest and first proposed dam.
- An Environmental Impact Study (EIS) commissioned by the federal energy agency Eletrobrás in conjunction with the companies hoping to build the São Luiz do Tapajós dam says the project will cause a quick disappearance of habitat, loss of animals and reduction of their populations. Still, the EIS concludes the dam will cause little environmental impact.
- In an independent analysis of the EIS commissioned by Greenpeace, scientists criticized the methodology and results of the document, noting that it failed to identify or misidentified
- Because so little is known about Tapajós aquatic ecology, there is an urgent need for more studies before building begins, say experts. The hydroelectric project could jeopardize commercial fish species, the pink river dolphin, giant otter and black caiman. One fear is that the reservoir will concentrate dangerous levels of toxic mercury, poisoning fish and people.

Fish kills at Amazon’s Belo Monte dam point up builder’s failures
- In April, the Norte Energia consortium — builder of the now operational Belo Monte dam — was fined US$10.8 million for the death of 16.2 million tons of fish. Another flurry of fish deaths has occurred since then, and fishermen fear more to come.
- Critics say the dam’s construction has had negative impacts on the Tabuleiro do Embaubal, one of the most important turtle breeding sites in the Amazon basin; 20,000 Giant Amazon River Turtles (Podocnemis expansa) lay their eggs there annually.
- The dam’s builder and scientists agree Belo Monte will drastically curtail the annual floods that force the Xingu River over its banks and into the rainforests, harming aquatic connectivity and likely impacting genetic diversity and ecosystem health. Extreme drought due to climate change adds to that risk.
- Indigenous and traditional fisheries suffered steep declines during the building of the dam, with fishermen and scientists noting the disappearance of important commercial fish species such as the piraíba. Those losses could continue in future.

Pre-Columbian Amazon settlement primarily ate fish — more sustainable?
- A study of the Central Amazon’s Hatahara settlement found that, circa 750-1230 AD, 76 percent of the animals people ate were fish and just 4 percent were mammal — very different from American / European prehistoric groups who ate more meat than fish.
- Thirty-seven different fish taxa were identified in the Hatahara samples, indicating that the people of that time were exploiting a much more diverse spectrum of food species than today, perhaps making their fishing and dietary habits more sustainable.
- One mystery: just one river turtle genus (Podocnemis) dominated the reptile diet, even though a diversity of turtle taxa can be found in the region.
- While these results are intriguing, more study is needed at more locations (inland, interfluvial and wetland settlements) to arrive at a regional understanding of available animal resources and the diets of Pre-Columbian Amazon settlements over time.

Amazonian catfish’s 5,000-mile migration endangered by dams
- Brachyplatystoma rousseauxii, a commercially valuable catfish species and an apex predator, grows to 3 meters long. Scientists have long suspected that it makes an extraordinary migration from the Amazon headwaters to the Amazon Basin and back.
- Now researchers — using an innovative technique that examines the chemical composition of adult catfish ear bones — have found proof of the 8,000-kilometer journey. The fish can drift as far downstream as the Amazon estuary, then swim back to the headwaters stream where they began, or to other Amazon tributaries.
- Unfortunately for the catfish, more than 400 dams have been built, are under construction, or are planned for the Amazon Basin and Andes feeder streams. Global research has shown that long homing migrations by fish are incompatible with dams.
- The researchers are urging governments in six Amazon Basin countries to reconsider and redesign their Amazon dam plans, or risk losing this natural wonder — along with seeing negative impacts to the entire freshwater food chain.

Keeping Amazon fish connected is key to their conservation
- Amazon basin fish species living in lakes, floodplain forests and river systems need a high degree of connectivity to stay genetically diverse and healthy, but this connectivity is threatened by proposed dams and increased drought due to climate change — both of which threaten rainy season flood cycles.
- A new study finds that understanding the dynamics of Amazon metapopulations —subgroups separated from other subgroups in lakes and river systems, which periodically mix during flood seasons or migrations — is critical to conservation.
- Unless Brazil’s federal government and communities take freshwater conservation seriously — protecting interlinked lake, floodplain and river systems — commercial fisheries, and even forest diversity (due to fish seed dispersal) could be seriously at risk.

Aquaculture comes to Lake Victoria, but will it help wild fish?
- Lake Victoria’s commercial fish stocks have plummeted due to overfishing, invasive species, pollution, and changing climatic conditions, among other factors.
- Now fishermen, researchers, and government officials alike are embracing cage aquaculture as a way to boost profits and fish supplies, as well as give the lake’s free-swimming fish a reprieve.
- However, cage fish farming has caused problems elsewhere in the world, in part due to the use of chemicals and the release of waste products, such as dead fish, uneaten feed, and feces.

Release herpes virus to kill invasive carp in Australia, groups urge
- A coalition of conservationists, recreational fishers and farmers want Australia’s state and federal governments to get rid of European carp, or “Australia’s worst freshwater pest”, by releasing carp-specific herpes virus in Murray river.
- Scientists have shown that the koi herpesvirus, also called Cyprinid herpesvirus 3 (or CyHV-3), can be used as an effective biocontrol against the invasive carps.
- The scientists have also found that the virus doesn’t affect native Australian or important introduced species of fish, or other groups of animals including humans.

Feeds: news | india | latam | brasil | indonesia