image: Biologist Sean Brennan paddles his equipment-laden kayak during a study that developed a new way to use strontium isotope ratios in 'fish ear bones' of chinook salmon caught at sea to identify in what streams within Alaska's Nushagak River watershed the fish hatched and lived before migrating to Bristol Bay and the Pacific. Brennan, a University of Utah biology graduate, did the study as a doctoral student at the University of Alaska Fairbanks and performed the lab work in Utah. He now is a postdoctoral researcher at the University of Washington. This material relates to a paper that appeared in the May 15, 2015, issue of Science, published by AAAS. The paper, by S.R. Brennan at the University of Alaska, Fairbanks in Fairbanks, AK, and colleagues was titled, 'Strontium isotopes delineate fine-scale natal origins and migration histories of Pacific salmon.' view more
Credit: [Credit: Thure Cerling, University of Utah]