Young boy fishing in Tonle Sap at sunset.

Freshwater Ecosystems

The areas on which humanity depends for its most precious resource are under increasing pressure.


Fresh water is the lifeblood of our planet, and freshwater ecosystems connect people with the resources they need to thrive. But when rivers, lakes and wetlands are degraded, their ability to provide reliable supplies of clean water — and to support the species on which millions of people depend — is threatened.

The planet’s freshwater ecosystems are in crisis: Research found that populations of monitored freshwater species have fallen by 84 percent and nearly one-third of wetland ecosystems have been lost since 1970 due to human activities that degrade habitats and decrease water quality.

But despite their vital contributions to humans and biodiversity, freshwater ecosystems receive only a small percentage of the funding dedicated to nature conservation, explained Robin Abell, a co-author of a recent review of these findings published in the journal Science, who leads Conservation International’s freshwater work.

“Freshwater ecosystems connect headwaters with oceans, land with water and people with the resources they need to thrive,” Abell said. “However, they have historically been ignored during the development of conservation initiatives such as protected areas and other management interventions.”

“Freshwater and terrestrial conservation need to go hand-in-hand to receive the full suite of benefits that nature can provide,” she said. “This will require strong policy that recognizes the connections between terrestrial and freshwater systems and that treats those systems as equal in importance.”


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It's 2023 — is this the year fresh water has its moment?

© Yang Nan

From roaring rivers to seasonal springs, freshwater is essential to life on Earth. Yet these ecosystems — and the species within them — tend to be overlooked, receiving only a fraction of the attention and funding dedicated to nature conservation. 

As we look ahead to the conservation issues shaping 2023, Conservation News sat down with Conservation International freshwater scientists Derek Vollmer and Ian Harrison to discuss what this year has in store for freshwater conservation — and how they are working to address it.

What's on your radar in 2023?

Derek Vollmer: This year, we’re expecting a spotlight on freshwater issues. Traditionally, freshwater has been thought of as a local issue, but this March, the United Nations is set to convene its first water conference in nearly 50 years — it’s a recognition that the health of Earth’s freshwater systems is connected to the big challenges of our time, including climate change, food security and economic development. 

Seems like a big deal, so what can we expect?

Ian Harrison: Unlike the recent U.N. biodiversity and climate summits, the water summit doesn’t include a global negotiated agreement. Water management is too local for an international framework; decisions tend to reflect everything from local geology to rainfall and weather patterns. But the summit is valuable in that it raises water as an issue of global importance in its own right and provides an opportunity to reiterate recent commitments to protect, conserve and restore freshwater sources

The U.N. stage will also elevate the voices of marginalized communities that are bearing the brunt of climate change, including increased droughts and floods. U.N. events are widely regarded as the place for countries that don’t have the same political and economic spotlight as powerful countries to sit around the same table and express their opinions equally. 

What are some challenges facing freshwater?

DV: Water is a very complex issue — one that tends to be oversimplified to mean water scarcity. But that doesn’t acknowledge the full environmental, social and systemic issues related to water management — such as the alarming decline in freshwater biodiversity and risks to communities that rely on freshwater resources for food and livelihoods. We’re looking to change that with recently published research that advocates for a more nuanced and holistic approach to water management.

What did you find?

IH: A degraded ecosystem can’t provide clean water or regulate floods or store carbon — all of which people need. Maintaining a healthy freshwater ecosystem takes integrated management and governance — yet many environmental crises are caused by ineffective governance, such as not enforcing pollution regulations. To sum it up: Watersheds can’t be managed with “silver bullet” solutions. There must be local stakeholder engagement and coordination between sectors like environment, health, energy and agriculture. This is not a new idea, but the water sector has been slow to make needed changes and open decision-making to new voices and perspectives. 

Can you share an example? 

DV: This year, we’re working on a project with the Priceless Planet Coalition on Madagascar’s largest inland lake: Lake Alaotra. Surrounding the lake is one of the largest rice-growing areas in the country. It’s also home to many freshwater fish. But deforestation is causing erosion, which leads to landslides and sediment that clogs waterways — hurting fish populations. This chain reaction ultimately threatens local communities, which rely on the lake for food and income. The project focuses on restoring the area’s forests, which soak up significant amounts of carbon to help mitigate climate change. At the same time, we’re looking at how that restoration impacts the health of the lake. If you only focus on planting trees to store carbon, where you choose to put those trees is somewhat insignificant. But the trees’ location has a big impact on how much sediment ends up in the water. By taking a coordinated approach and being thoughtful about the entire ecosystem, we can break down barriers between projects and improve their outcomes.

What do you think is overlooked in your work?

IH: What’s missed is the deep connection between watersheds and other ecosystems. Freshwater and terrestrial conservation need to go hand-in-hand. You can't have one without the other, yet they are often siloed when water management decisions are made. Think about the Amazon rainforest. People tend to focus on the forest, but that ecosystem exists because of a massively complex watershed. Deforestation in the Brazilian Amazon has surged in recent years; we need to halt and reverse this destruction. But conservation efforts will be compromised if they don’t include protecting the watershed. A study in the Amazon showed that conservation planning that addresses both terrestrial and freshwater systems together can increase freshwater benefits up to six times. 

We also have to be thinking about freshwater and marine systems in an integrated way. For example, if you have a marine protected area along a coast, but the river that feeds into it runs along a deforested area, this could spill massive amounts of sediment into coral reefs and other ecosystems that the protected area is meant to conserve. Bottom line, investments to protect a coastal area will count for little if you've got a polluted river running into it.  

What makes you hopeful for 2023?

IH: We're hopeful that more people from outside of the conventional water conservation sectors will be focusing on watershed health in 2023. And there are signs that this is catching on — the critical international agreements at the recent biodiversity and climate summits both included strong messaging about the importance of protecting freshwater. The knowledge and international collaboration are there – our job now is to put it into action. 

Further reading: 

Mary Kate McCoy is a staff writer at Conservation International. Want to read more stories like this? Sign up for email updates. Also, please consider supporting our critical work.

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