|Document Type:||Journal Article|
|Title:||Interannaul variability in the effects of physical habitat and parentage on Chinook salmon egg-to-fry survival|
|Author:||P. Roni, Christopher L. Johnson, Trenton DeBoer, G. R. Pess, Andrew H. Dittman, David A. Sear|
|Journal:||Canadian Journal of Fisheries and Aquatic Sciences|
|Keywords:||Chinook salmon, suvival, egg-to-fry,|
Mortality during incubation is believed to be a major factor limiting the recovery of many salmon populations though direct field measurements of egg-to-fry survival are rare or small in scale. To determine the effects of physical habitat (river reach, fine sediment intrusion, scour) and parentage (mating/source of gametes) on Chinook salmon (Oncorhynchus tshwaytscha) egg-to-fry survival and developmental stage across a basin, we constructed 324 artificial redds in nine reaches over four years in the Yakima River Basin, Washington, USA. Mean egg-to-fry survival ranged from 49 to 69% annually from 2009 to 2012 brood years. Survival was significantly different among reaches in 2010, but not 2009, 2011 or 2012, while mating was a significant factor in all years but 2010. In contrast, developmental stage differed significantly among reaches and matings in all four years. Percent of fines, days-in-gravel and median particle size explained only a small (<10%) additional amount of variation in survival or developmental stages. Our results suggest that parentage and reach within a basin are major factors influencing egg-to-fry survival, but their relative influence vary annually presumably depending on the magnitude of high flows and scour during incubation.
|Theme:||Recovery and rebuilding of marine and coastal species|
Characterize the population biology of species, and develop and improve methods for predicting the status of populations.
Develop methods to use physiological, biological and behavioral information to predict population-level processes.