IRES: Aquatic Bright Spots: Ecological Resilience in Northern Lakes and Rivers

University Of Wisconsin-Madison, Madison WI

Investigators

Abstract

Changes in climate are significantly altering the freshwater habitats of inland lakes and rivers. Despite concern over the impacts of a changing climate on aquatic ecosystems, some lakes and rivers are holding up surprisingly well. The aquatic ecosystems of northern Mongolia represent one such “bright spot.” While air temperatures in the region have warmed almost three times faster than the global average, coldwater fish populations in northern Mongolia appear to be surprisingly robust. This project builds on nearly 20 years of ecological research, monitoring, and sample collections to understand the factors underlying the resilience of Mongolia’s lakes, rivers, and fish populations. Each summer, four undergraduate and four graduate students travel with American and Mongolian scientists to Lake Hovsgol and the Eg River in Mongolia to engage in research for six weeks. Here, they conduct field ecology research projects in two-person grad-undergrad teams. Student participants hone their research project proposals and outreach plans through a pre-trip distributed seminar and present results after the expedition at an online virtual symposium. Student research teams investigate three broad hypotheses about the factors contributing to resilience of aquatic ecosystems. First, via “behavioral thermoregulation,” fish may be able to select microhabitats where temperatures remain more favorable to growth and survival. Second, intra-specific variation in characteristics such as temperature tolerance may allow populations to persist in warming waters. Third, changing ecological interactions, including predator-prey and host-parasite relationships, may either offset or exacerbate the direct effects of warming. Experiments and observational studies test these hypotheses using cutting-edge tools such as DNA metabarcoding to investigate diets and microbiomes of endangered fishes, electronic tags to track fish movements, and data logging sensors to understand variation in the abiotic environment. The Intellectual Merit of this project is centered on improving our understanding of the effects of a changing climate on natural ecosystems. The Broader Impacts include improved management approaches for U.S. fisheries impacted by changes in climate and the training of 24 U.S. students in aquatic ecology research methods in an international setting. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.