Rapid decline of Caspian Sea level

© 2025. Rebecca Court (1,12),* Matteo Lattuada (2,3,13), Nataliya Shumeyko (4), Mirgaliy Baimukanov (5), Tariyel Eybatov (6), Altynay Kaidarova (7), Elchin V. Mamedov (8), Eldar Rustamov (9), Aselle Tasmagambetova (7), Matthias Prange (10), Thomas Wilke (11), Christopher Hassall (1) & Simon J. Goodman (1).*

(1) School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK.
(2) Landscape Ecology and Environmental Systems Analysis, Institute of Geoecology, Technische Universität Braunschweig, Brunswick, Germany.
(3) Plant Ecology, Institute of Ecology, Technische Universität Berlin, Berlin, Germany.
(4) Kaspika Caspian Seals Conservation Agency, Moscow, Russia.
(5) Institute of Hydrobiology & Ecology, Almaty, Kazakhstan.
(6) Museum of Natural History, Baku, Azerbaijan.
(7) Central Asian Institute of Ecological Research, Almaty, Kazakhstan.
(8) Fisheries and Aquaculture Research Centre, Biodiversity Protection Service, Ministry of Ecology and Natural Resources, Baku, Azerbaijan.
(9) Ramsar Regional Initiative of Central Asia (RRI-CA), Ashgabat, Turkmenistan.
(10) MARUM – Centre for Marine Environmental Sciences, University of Bremen, Bremen, Germany.
(11) Institute of Ecology and Systematics, Justus Liebig University Giessen, Giessen, Germany.
(12) School of Earth and Environment, Faculty of Environment, University of Leeds, Leeds, UK.
(13) Plant Ecology, Institute of Ecology, Technische Universität Berlin, Berlin, Germany.
*E-mails: Rebecca Court (bs22rmc@leeds.ac.uk); Simon J. Goodman (s.j.goodman@leeds.ac.uk).

Rapid decline of Caspian Sea level threatens ecosystem integrity, biodiversity protection, and human infrastructure

Abstract

The Caspian Sea is the world’s largest landlocked waterbody, providing habitat for hundreds of endemic and migratory species, along with ecosystem services that sustain millions of people. Global warming is projected to drive declines in water levels of up to 21 m by 2100.

A Caspian recession example: Coastal recession in the northeastern Caspian Sea (2001-2024), satellite imagery from NASA Worldview. The orange polygon indicates the boundary of an officially recognised ecologically significant marine area (EBSA Komsomol Bay), which used to support large aggregations of moulting seals, but which has now become desiccated. Credit: Simon Goodman, University of Leeds, Leeds, UK.

Using geospatial analyses, we assessed the impact of sea level decline on habitats, protected areas, and human infrastructure. We show that a water level decline of just 5–10 m will critically disrupt key ecosystems (including habitats for endemic Caspian seals and sturgeon), reduce existing marine protected area coverage by up to 94 %, and render billions of dollars of civil and industrial infrastructure obsolete.

Replacing traditional static conservation planning with a pre-emptive, dynamic approach that allows protected areas to track shifting ecosystems, is recommended to help endemic Caspian Sea biodiversity adapt to these changes, and to avoid conflicts with mitigation efforts directed at protecting human activity.

Download the full text on Communications Earth & Environment.

For citation: Court R., Lattuada M., Shumeyko N., Baimukanov M., Eybatov T., Kaidarova A., Mamedov E. V., Rustamov E., Tasmagambetova A., Prange M., Wilke T., Hassall C., Goodman S. J. Commun Earth Environ 6, 261 (2025). https://doi.org/10.1038/s43247-025-02212-5.

Source: Communications Earth & Environment, Nature.
In the top photo: The Caspian seal pup. ©Sarah Del Ben, Central Asian Institute of Ecological Research, Almaty, Kazakhstan.