Collaborative Research: RAPID: Testing the Mechanisms and Consequences of an Adaptive Response to a Catastrophic Fire and Heatwave in Stream Frogs

Michigan State University, East Lansing MI

Investigators

Abstract

Climate change is causing more extreme weather events such as fires and heatwaves. In addition to the tragic loss of human life, such events have a devastating effect on animals and plants. One challenge for biologists is to understand how species will respond to such climatic events – if they can cope or if they will go extinct. To meet this challenge, researchers must identify what biological changes occur following extreme climatic events. This project seeks to understand how populations of tailed frogs, which are found in cold streams of the Pacific Northwest, have coped in the aftermath of a large fire and heatwave. The research team had been studying the physiology and genetics of tailed frogs in this region for 4 years before the fire and heatwave occurred in 2020-2021. Only a year and a half after these events, the researchers will measure what physiological, genetic, and other changes have occurred in the frog populations. This will allow the researchers to 1) understand how the frog responded to extreme climatic events, 2) predict how they will respond in the future, and 3) present their findings to local land managers to discuss possible conservation strategies for frogs and other freshwater aquatic species in the area, and 4) train a postdoctoral and undergraduate researcher. Species can respond to extreme climatic events via plasticity and/or adaptation. How populations respond may depend on the magnitude and severity of environmental change, although investigations of responses to extreme climatic events are rare. For four years, the researchers have been studying the thermal sensitivity and adaptive capacity of coastal tailed frogs (Ascaphus truei), a dominant herbivore in fast-flowing streams in the Pacific Northwest, to predict their responses to climate change. They have measured stream thermal characteristics, tadpole thermal physiology, and identified genomic markers associated with those variables. In 2020, an intense forest fire burned on top of two of the study streams. A year later, an unprecedented heatwave impacted all of the sites. The proposed research will test hypotheses about changes that have occurred at the environmental, physiological, and genomic levels in response to these climatic events. This research will (i) identify patterns of thermal physiological change in fire- and heatwave-affected populations, (ii) test for signatures of genetically-based adaptation to the fire and heatwave, and (iii) integrate physiological and genomic findings to predict the degree to which persistence of populations changes as a result of each extreme climatic event. 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.