Wetlands: the ultimate biodiversity hotspot


Wetlands provide habitats and breeding grounds for countless plant and animal species, but we’re losing these critical ecosystems at an alarming rate – as World Wetlands Day will highlight this Sunday. Ambitious policy and on-the-ground action is needed to conserve wetlands and save their unique wildlife, argue members of the IUCN Species Survival Commission (SSC) Freshwater Conservation Committee.

Goonch (Bagarius yarelli)

The book Freshwater: The Essence of Life, published in 2010, made the case that “freshwater ecosystems are the ultimate biodiversity hotspot. They contain a greater concentration of life than anywhere else and are seriously imperiled”. Ten years on, these facts remain true, and this year, World Wetlands Day on February 2 is focused on Wetlands and Biodiversity. The day highlights the rich diversity of wetlands, while raising awareness about their plight and how we can act to reverse their loss. World Wetlands Day also marks the signing of the Ramsar Convention on Wetlands on February 2, 1971.

These ecosystems and their associated biodiversity face disproportionately high levels of threat.

Wetlands extend across inland and coastal zones. They include the rivers, lakes, marshes, swamps and other ‘wet lands’ found inland. But the Ramsar Convention also includes coastal wetlands such as saltwater marshes, estuaries, mangroves, lagoons and coral reefs in its definition. This is important because inland and coastal wetlands are inextricably linked to each other, and with the terrestrial landscapes through which they run. It is for this reason that members of the IUCN Species Survival Commission are promoting the concept of the ‘aquascape’ – a term that highlights the connectivity of fresh, marine and ‘transitional waters’ (those waters between the inland and sea waters, such as estuaries, lagoons and deltas), as well as the ecological processes that occur across them.

For example, sediment picked up by the Marañón River – one of the world’s few remaining long, free-flowing rivers, located in the upper part of the Amazon basin – is a major contributor to the sediment load of the main part of the Amazon. Impacts to the Marañón, caused by proposed dams and massive dredging on the upper Amazon tributaries (such as the Hidrovía Amazónica project), would not only have catastrophic impacts on the regional biodiversity of the Marañón, but also on the river channels and floodplains further down the Amazon.

The Marañón River The Marañón River Photo: Marañón Waterkeeper collection.


For these reasons, the SSC Freshwater Conservation Committee and SSC Freshwater Fish Specialist Group are working closely with Marañón Waterkeeper, an NGO working to protect and promote the river, and their partners to address these issues. This includes the submission of a motion to IUCN’s World Conservation Congress, advocating for the Protection of the Marañón and other free-flowing rivers of Peru. We are also seeking to implement biodiversity surveys to assess the extent of potential biodiversity loss that would be caused by such development and to prevent it.

Encouraging conservation action

The urgency for action, in particular for freshwater ecosystems, has been indicated by WWF’s Living Planet Reports, which have shown that these ecosystems and their associated biodiversity face disproportionately high levels of threat. A recent study has shown that the Chinese paddlefish, one of the world’s largest fishes, has gone extinct. This trend of high extinction risk is common across many large freshwater species, according to a study published last year. The New York Times notes that while this represents an important challenge to conservation, there are opportunities to save many species. The loss of these large, compelling freshwater species highlights the threats to freshwater ecosystems and all the species living within them, and can be used to motivate conservation action.

Parabotia curtus In Kameoka, Japan, the loss of one of the last remaining breeding sites for the Critically Endangered Kissing Loach was prevented, thanks to the collaborative efforts of IUCN Japan, the IUCN SSC Freshwater Fish Specialist Group, local government and other partners (Parabotia curtus). Photo: Tsukasa Abe


Although it is often difficult to draw the same attention to smaller species, there are some success stories. For example, in 2017 the SSC Freshwater Fish Specialist Group worked with colleagues from IUCN Japan, the National Conservation Society of Japan, and Kyoto University to protect a wetland that was threatened by the development of a soccer stadium in the city of Kameoka, Japan. The site was one of the last remaining breeding sites for a Critically Endangered species of fish, the kissing loach. The collaboration of these groups and the foresight of the local government resulted in relocation of the stadium.

Another example is of work in Mexico to save an Endangered aquatic salamander, the mountain stream siredon, or Zempoala axolotl. This remarkable species, which can regenerate its limbs, has an extremely restricted distribution, living in just a few high mountain streams and lakes in the Lagunas de Zempoala National Park. It also has strong cultural importance.

The loach and the axolotl provide examples of how local action is at the forefront of sustaining wetland species.

The name axolotl comes from the Nahuatl: atl (water) and xolotl (monster): aquatic monster. In Nahuatl mythology, axolotls are the aquatic representation of the god Xolotl, the twin brother of Quetzalcoatl, who looked like a monster because of his birth as a twin. Xolotl is associated with the idea of movement and life. The cultural importance of this species comes from the Aztecs, who used them as medicine (some local people still do for respiratory illness), food and ceremonies, and they were later adopted as pets.

Currently the species faces threats from habitat degradation and from invasive species. Non-native trout and carp that have been introduced to the lakes are putting the species at risk by eating axolotl eggs, young and adults. The Autonomous University of Morelos (which includes representation from the SSC Freshwater Conservation Committee) and the non-profit Freshwater Life are working with the local indigenous community to eradicate non-native fishes so that the culturally important axolotl can flourish.

Both the loach and the axolotl represent examples of how local action is at the forefront of sustaining wetland species. These projects bring awareness to the biodiversity of our wetlands and drive actions to conserve it. Groups like the SSC Freshwater Conservation Committee can bring together examples of conservation success from around the world to present unified messages for the protection of ecosystems.

The Endangered Mountain Stream Siredon The Endangered Mountain Stream Siredon, or Zempoala axolotl, can regenerate its limbs. Photo: Juan Antonio Reynoso Moran


The way forward

This year, 2020, is an especially important year for biodiversity, including wetlands and their species. The Convention on Biological Diversity meets in China in October to agree on the Post-2020 Global Biodiversity Framework, a process in which IUCN has been closely involved, as have the International Organization Partners of the Ramsar Convention on Wetlands. Freshwater ecosystems are included in the draft targets and indicators for post-2020, and IUCN Commission members are reviewing those documents and identifying where recommendations can be made to ensure that freshwater ecosystems are effectively monitored as part of these global policies.

In this important year for biodiversity, we urgently need local and global action to conserve wetlands and save their unique wildlife, from efforts on the ground to policy-making in international fora.

IUCN’s World Conservation Congress will be held in Marseille in June, and one of its themes focuses on conserving freshwater ecosystems to sustain life. Just before the IUCN Congress, on May 16, World Fish Migration Day will celebrate the importance of free-flowing rivers to migratory fishes, but also to others species that rely on these healthy ecosystems, including the people who rely on the resources they provide.

So, February 2, World Wetlands Day, is an important day to draw attention to wetlands and their biodiversity. But this should just be the start. In this important year for biodiversity, we urgently need local and global action to conserve wetlands and save their unique wildlife, from efforts on the ground to policy-making in international fora.

Ian Harrison (Co-Chair IUCN SSC Freshwater Conservation Committee; Co-Chair, IUCN WCPA Freshwater Specialist Group), Topiltzin Contreras MacBeath (Co-Chair IUCN SSC Freshwater Conservation Committee), Matt Gollock (Chair, IUCN SSC Anguillid Eel Specialist Group), Harmony Patricio (Co-Chair, IUCN WCPA Freshwater Specialist Group)



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