A chemical signature recorded on the ear bones of Chinook salmon from Alaska’s Bristol Bay region could tell scientists and resource managers where they are born and how they spend their first year of life. (more…)
Tag Archives: chinook salmon
Not having enough Chinook salmon to eat stresses out southern resident killer whales in the Pacific Northwest more than having boatloads of whale watchers nearby, according to hormone levels of whales summering in the Salish Sea.
In lean times, however, the stress level normally associated with boats becomes more pronounced, further underscoring the importance of having enough prey, according to Katherine Ayres, an environmental and pet-behavior consultant who led the research while a University of Washington doctoral student in biology. Ayres is lead author of a paper appearing online June 6, in the journal PLoS ONE.
In a surprise finding, hormone levels show that southern resident killer whales are best fed when they come into the Salish Sea in the late spring, Ayres said. The Salish Sea includes Puget Sound and the straits of Georgia, Haro and Juan de Fuca. Once there they get a necessary boost later in the summer while eating Chinook salmon at the height of the Fraser River run. (more…)
USGS scientists and academic colleagues investigated how California’s interconnected San Francisco Bay and Sacramento-San Joaquin Delta (the Bay-Delta system) is expected to change from 2010 to 2099 in response to both fast and moderate climate warming scenarios. Results indicate that this area will feel impacts of global climate change in the next century with shifts in its biological communities, rising sea level, and modified water supplies.
“The protection of California’s Bay-Delta system will continue to be a top priority for maintaining the state’s agricultural economy, water security to tens of millions of users, and essential habitat to a valuable ecosystem,” said USGS Director Marcia McNutt. “This new USGS research complements ongoing initiatives to conserve the Bay-Delta by providing sound scientific understanding for managing this valuable system such that it continues to provide the services we need in the face of climate uncertainty.” (more…)