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Otter with fish

Bring living waters back to our planet

Demanding the Indian government take action to clean and save the nation’s Mother River, the Ganga, activist and former civil engineer Professor G.D. Agarwal died from heart failure in 2018, after fasting for 111 days. Agarwal’s hunger strike remains symbolic of the mounting desperation many of us feel faced with the fragility of rivers, lakes, and wetlands, and the precarious future of the biological life they contain.

Rivers, lakes, and wetlands support extraordinary diversity. Such bodies of water host more species per square kilometre than forests or oceans. Yet they are losing this biodiversity two to three times faster than forests and oceans. Populations of freshwater animals, including river dolphins, sturgeon, beavers, crocodiles, and giant turtles, have already plummeted by 88%. More than a quarter of freshwater species are headed for extinction unless we act now. Accompanying these declines are severe losses in the services that freshwater ecosystems provide to billions of people, including impoverished and vulnerable communities. As well as being reliable stores of fresh water, healthy ecosystems support productive fisheries, nourish agricultural lands, and protect us from floods and droughts.

Glen Canyon Dam
A 2018 high flow from Glen Canyon Dam on the Colorado River—one of several experimental environmental flow releases to restore threatened fish species and critical ecosystem functions. (Image by Todd Wojtowicz, US Geological Survey, USA)

Despite irrefutable evidence of an ongoing collapse, coordinated action to reverse the decline of freshwater biodiversity remains weak or lacking, at local, regional, and global levels. This sparked the launch, by members of the international conservation community, of an Emergency Recovery Plan aimed at halting freshwater biodiversity loss, restoring ecosystem services, and safeguarding our life support systems before it is too late. Human impacts on freshwater biodiversity are the result of multiple pressures. Under the plan, recovering freshwater diversity requires six priority actions—restoring river flow regimes, protecting and restoring critical habitats, ensuring connectivity, improving water quality, managing the exploitation of freshwater resources, and preventing and controlling non-native species invasions.

Together, water abstraction, regulation, and pollution are a leading cause of freshwater biodiversity losses globally. Changes in the magnitude and timing of river flows and water levels in lakes and wetlands have degraded habitats, disrupted connectivity pathways, and curtailed important processes, such as sediment, nutrient, and energy dynamics. Freshwater species have lost life cycle cues essential for migration and breeding. The recovery plan urges everyone active in natural resources stewardship to accelerate the implementation of “environmental flows”—the quantity, timing, and quality of freshwater flows and levels necessary to sustain aquatic ecosystems which, in turn, support human cultures, economies, sustainable livelihoods, and well-being.

We now have the tools and methods to assess the water needs of ecosystems and species. Environmental flows are being incorporated into policies and regulations, basin plans, and the design and operation of water infrastructure, including dams, diversions, and sewage treatment works. Stories in Listen to the River demonstrate how governments have been able to safeguard flows or bring clean water and life back to rivers that were running dry. The 2018 Brisbane Declaration and Global Action Agenda on Environmental Flows sets out recommendations for practitioners to enhance the implementation of water recovery and protection efforts. Growing understanding of human-flow relationships is informing socio-cultural objectives for freshwater ecosystem use and condition, advancing environmental water management as a social process.

Colorado River
The Colorado River re-inhabits its dry channel in México during the 2014 transboundary environmental pulse flow that reconnected river and coastal delta for the first time in decades. (Image by Eloise Kendy, The Nature Conservancy)

Major freshwater ecosystems and biodiversity have all too long been buried within international and national policy agendas designed for terrestrial systems. It is time to focus on rivers, lakes, and wetlands specifically. Governments, with other leading public, private, and non-governmental organisations, will gather in 2021 to agree a framework for biodiversity that aligns with sustainable development goals. The dialogue has begun as to which targets, indicators, and actions within international agreements will combat freshwater biodiversity loss.

Our planet has shown unimaginable resilience, but at a cost we have not fully reckoned—precipitous declines in the health and biodiversity of freshwater ecosystems will undoubtedly push us beyond the bounds of sustainability. This impending catastrophe, along with climate change and pandemics, epitomises the global risk landscape many of us navigate day to day. We have reached a pivotal moment when all of us, whether policymakers, indigenous and business leaders, resource managers, engineers, scientists, and the public, must re-evaluate priorities and mobilise to protect and recover our freshwater ecosystems for the long term.

Meeting the imperative for accelerating implementation of environmental flows is central to that path and that potential.

Agarwal gave up water in the week before he died. But his hope, like ours, for a world where people understand, value, and conserve freshwater biodiversity, will never evaporate.

Feature image: A giant otter (Pteronura brasiliensis) catching a fish in the Pantanal Wetland, Brazil.
Image credit: R.Isotti, A.Cambone / Homo Ambiens / WWF.

Recent Comments

  1. Fred Ryan

    What are the details for the 2021 international meeting — you write “… will gather in 2021 to agree a framework for biodiversity..” but without mention of the place or specific date. Are these decided?

  2. Michael McClain

    Hi Fred, We are referring to the process underway to establish the post-2020 global biodiversity framework. This process was planned for 2020 but has been delayed due to COVID-19. The status and related events can be monitored at https://www.cbd.int/. Thanks for your question!

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