A major new international review co-authored by Professor Gemma Harvey, Professor of Physical Geography in the Department of Geography and Environmental Science at Queen Mary University of London, highlights how species that physically modify freshwater environments interact with climate change, and why understanding these processes is becoming increasingly important.
Published in WIREs Water, the review brings together global evidence on freshwater ecosystem engineers - organisms such as animals, plants and insects that physically shape their surroundings by building structures, altering riverbeds or regulating water flow. In rivers, lakes and wetlands, these activities can influence how ecosystems respond to climate pressures including flooding, drought and rising temperatures.
Figure: Climate change, ecosystem engineers and freshwater systems. A conceptual model showing how changing environmental conditions influence species, their activities and climate feedbacks.
The authors find that research on freshwater ecosystem engineers has lagged behind comparable work in terrestrial ecosystems. Existing studies focus far more on hydrological extremes such as flooding than on temperature-driven pressures and drought, despite these becoming increasingly severe under climate change.
The review also highlights strong geographical biases in the scientific literature. Most studies to date have been carried out in the United States and Europe, while regions projected to experience some of the most dramatic climate shifts remain under-represented. In addition, research has focused heavily on large, charismatic species, with far less attention paid to smaller but highly influential organisms such as insects and crustaceans.
This new review builds on Professor Harvey's wider research into ecosystem engineers. In 2025, she led the first global study to quantify how animals act as "architects of the Earth", revealing how species ranging from beavers to termites shape landscapes and ecological processes at a planetary scale. Together, the two studies underline the importance of understanding organisms not simply as inhabitants of ecosystems, but as active agents shaping environmental change.
Professor Harvey said:
"Freshwater ecosystems are often overlooked in climate research, despite being central to biodiversity, water security and human wellbeing. This review shows that ecosystem engineers can fundamentally shape how rivers, lakes and wetlands respond to climate change, but it also highlights how much we still do not know."
The authors argue that addressing these knowledge gaps will be essential for improving conservation, restoration and climate adaptation strategies. Future research, they suggest, should expand into under-studied regions, examine multiple ecosystem engineers acting together, and better integrate climate pressures such as warming and drought into freshwater science.
As climate change intensifies, understanding how freshwater ecosystems respond, and the role that organisms play in shaping those responses, will be critical for protecting some of the world's most vulnerable environments.
View the full paper:
Albertson, L. K., Fritz, S. F., Oakland, H., Bushey, L. J. L., French, A., Heili, N. M., Reyes de Merkle, J., Schmidt, S., Greig, H. S., Johnson, M. F. and Harvey, G. L. (2026). Feedbacks Between Climate and Freshwater Ecosystem Engineers. WIREs Water.
