STEWARDSHIP OF THE WEST Navigating Rough Water Randy Gimblett is a mediator for the natural world. After the Condit Dam on the White Salmon River in Washington was removed in 2011, several different groups, humans and piscine, began vying for the recently opened section of the river. Within a month, the endangered Chinook salmon returned to a 15-mile stretch of spawning habitat that had been closed off to them for nearly 100 years. In addition, the Yakama Nation, which holds rights to net the salmon, and the boating community, whose livelihoods and recreation depend on the river, began settling in to the new stretch of water. Gimblett, a UA professor in the School of Natural Resources and the Environment, knows the importance of research in conservation planning, and he wanted to provide the community with concrete data to make informed decisions about resource management and regulations. “This study could inform decommissioning dams in the future,” he said. “It’s an issue of endangered species on a river and no recovery plan in place.” Gimblett and Christopher Scott, co-investigator and a UA professor of water resources policy, received funding from an IE Faculty Exploratory Research Grant to conduct research during the summer of 2014. “No one had a clue about the level of river use or its impact on the salmon,” Gimblett said. “The theory is when boats float over the salmon, the fish get spooked and leave their beds. The frequency and intensity of the boats on the river could cause the salmon to leave hatching beds permanently.”
In a river system, warmer global temperatures can lead to decreasing water levels, later seasonal peak flows, and increased levels of sediment at the river bottom. “In order to prepare this recovering ecosystem for potential future degradation by climatic changes, it’s crucial to reduce non-climatic stressors such as over-use,” Gimblett said. Accordingly, the Yakama Nation has agreed not to net salmon until 2016. Based on his research, Gimblett predicts a period of two to three weeks during the late summer during which the river might see upwards of 100 to 150 rafts in a single day. During that time of year, river levels are at their lowest annual level, which could draw the boats down even closer to salmon spawning beds. Although current studies find little overlap between the largest spawning beds and the sections of river that see the most use, the fish are still in the process of returning to the recently opened area of the river. Gimblett hopes this phase of the study, which was completed in spring 2015, will help seed the protection of salmon species, foster an ecosystem that is resilient to climate change, and take into account the human river runners and tribal rights. “Because so many different groups use the river, it’s a tough case,” Gimblett said. “Our challenge has been how to create open, meaningful dialogue that makes them the stewards of the river.” WWW.ENVIRONMENT.ARIZONA.EDU/NEWS/NAVIGATING-ROUGHWATER WWW.ENVIRONMENT.ARIZONA.EDU/FERG-AWARDS
This study could inform decommissioning dams in the future. It’s an issue of endangered species on a river and no recovery plan in place.” Randy Gimblett
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PHOTO CREDIT: RANDY GIMBLETT
