Climate Change & Managing Effects of Increasing Wildfires on Southwestern Fishes

Authors: Scott Bonar

Year: 2022

Abstract

The largest wildfires in the State of Arizona have occurred since the start of the 21st century, related to ever increasing greenhouse gas concentrations in the atmosphere, climate change and resulting droughts. Wildfires can be particularly impactful in watersheds containing rare species. To be successful, biologists must become increasingly familiar with effects of these events on Southwestern fishes. Fishes can be affected during the fire itself, and following the fire through debris flows, removal of riparian canopies and other factors that affect stream temperatures and water quality. Temperature tolerances of desert fishes are not as high as one might expect; and reproduction of many species can be affected by changes in temperature, flow and substrate. Adaptation methods include preparing watersheds to reduce fire impact and debris flows; removing fish in advance of fires and then repatriating them later; restoring damaged canopies with plant species that provide the most shade and cooling potential. Mitigation methods include a strong education component on the effects of greenhouse gas emissions on climate change, resulting drought and associated fires. Here I show interactions that our lab has had with wildfires in the Southwest, selected research conducted, and experiences we have had over the last 20 years that can help inform fish/fire management.