Aquatic communities and climate change discussed in final two days 

Two presentations were given on fishes and aquatic communities, one for the upper basin and one for the lower basin.

Scott Vanderkooi of the United States Geological Survey (USGS) covered the upper basin, discussing the historic distributions of such species as Lost River and shortnose suckers, redband trout, sculpins and the variety of lamprey, among others.

Vanderkooi focused on the various changes to the upper Klamath system, such as alterations of the streambed, diversions and dams, and the way in which the river has gone from narrow and deep to wide and shallow. He also provided an update on the status of the various species, including how each population rates in productivity and abundance, among other indicators.

Vanderkooi concluded with questions about what will lie in the future for the river, including the results of removing four dams along the mainstem river and reintroducing salmonids to the areas that are now blocked by those dams. He said that he does not believe that removing the dams will return the river to historic conditions because other constraints on aquatic populations will still persist. He said that he thinks that “just pulling out the dams and expecting it to work” will not produce the results that restoration efforts seek.

Tommy Williams of the National Oceanic and Atmospheric Association took the floor to discuss the lower basin’s fishes and aquatic communities, with a focus on the restoration of salmonid populations.

Williams laid out a strategy for recovering salmon and steelhead species, including identification of the constraints on the specific population, identification of what factors indicate a viable population and understanding how the fish respond to changes in their environment.

“It takes a basin to raise a salmon,” Williams said, explaining that he believes removing the dams alone will not solve the problems facing salmonid populations, and that protecting only one habitat in a system will not produce the same results as addressing the system as a whole.

Siskiyou County’s Natural Resource Policy Specialist Ric Costales was present at the conference each day, and he asked Williams whether or not implanting eyed eggs, a part of the salmon life cycle, would be a viable short-term solution to address declines in populations. Williams responded, stating that while the practice can increase numbers in the short term, he believes the factors leading to the decline must be addressed or such an effort would not be an effective use of time and money.

The next presentation, by Josh Strange of the Yurok Tribe, covered the ecology and fishes of the estuary at the mouth of the Klamath and the nearby offshore marine environments.
Strange described some of the concerns present in the estuary, including sediment loading in nearby tributaries, vegetative species that “choke off” available habitat and invasive species, including the mud snail.

According to Strange, it appears that salmon are spending less time in the estuary, possibly as a result of the predation from California sea lions, which he said are responsible for approximately 2-8 percent of the predation on salmon. He said that human predation accounts for approximately 20-40 percent of salmon take and it has been hypothesized that in response, salmon are spending more time outside of the estuary, where a “plume” of fresh water extends, readjusting to fresh water conditions outside of areas that have traditionally been subject to heavy predation by both humans and animals.

Strange also talked about the tracking efforts for a number of species, including salmon, sturgeon and Great White sharks, among others. He concluded by stating that he believes that successful research should incorporate a diverse array of scientific disciplines, including the social sciences as well as the traditional knowledge of those who live in the areas that are to be researched and studied.

The final session, which took place on Friday, covered a number of topics related to climate change and its predicted effects on the Klamath basin.

Kathy Dello of Oregon State University discussed how scientists are assessing the current climatic changes and are trying to approximate how those changes will translate in the future.

Following Dello was Lori Flint of the USGS, who spoke about the expected changes to precipitation, snowpack and soil water content, among other predictions. She stated that the current situation is fairly well understood, but there are uncertainties in future predictions. Despite that uncertainty, she said, there is a general consensus on the direction of climate change and its implications for the basin.

Ron Neilson of the United States Forest Service presented a wide variety of climate change predictions from different models, which included predictions of an increase to the amount of vegetation burned by fire and an increase in carbon stored by plants.

Neilson also described other expected changes in response to climatic changes, including an increase in species movement to non-native areas, expansions of insect populations, more extreme floods and longer droughts, among others.

Stating that it is believed that some areas in the basin will get drier while others get wetter, Neilson said, “The future will not echo the past,” adding that the expected changes may require corresponding changes in the approach to management of the basin.

The final presentation was led by Jim Winton of the USGS, who discussed the potential impacts of climate change on infectious diseases of fish.

Winton stated that disease is a component of all ecosystems, and that the ecology of a disease is determined by features of the host, the pathogen itself and the environment both inhabit.

For fish, Winton said, levels of stress and temperature can affect their mortality rates  from disease. He said that with climate change, he said, movements of species and changing ecosytems may contribute to fish stress, and water temperatures are expected to rise, which has been shown to have a correlation to higher mortality in some diseases.

On the other hand, according to Winton, mortality from some diseases is suppressed by higher temperatures, creating a system in which future conditions are hard to accurately predict.

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