Linkages Between Climate Change and the Phenologies of Juvenile Salmon and Their Invertebrate Prey in Streams

EPA Grant Number: F13B20319
Title: Linkages Between Climate Change and the Phenologies of Juvenile Salmon and Their Invertebrate Prey in Streams
Investigators: Campbell, Emily Yvonne
Institution: Oregon State University
EPA Project Officer: Packard, Benjamin H
Project Period: September 29, 2014 through September 29, 2016
Project Amount: $84,000
RFA: STAR Graduate Fellowships (2013) RFA Text |  Recipients Lists
Research Category: Academic Fellowships , Fellowship - Aquatic Ecology


Climate change will likely shift the timing of important salmon and invertebrate life history events, such as emergence, due to their temperature- dependent metabolism. This study will consider three integrated aspects of climate and phenology: (1) climatic influences on the phenology of a predator (juvenile salmon); (2) consequences of climatic influences on fitness-related characteristics, including salmon size at age, growth and condition; and (3) linkages between the phenologies of juvenile salmon predators and their invertebrate prey.


A space-for-time experimental design will address these objectives through a comparative study of coho salmon predators and their invertebrate prey in six hydroclimatically variable streams on the Copper River Delta, Alaska. In the field, emerging salmon fry and invertebrates in these systems will be detected from April through November. Sequential ID tags will allow tracking of salmon growth rates in the field among streams. The spatial and temporal variation in thermal profiles among and within streams will be mapped. In the laboratory, salmon otoliths (calcium carbonate ear stones) will be extracted to determine exact age, gut contents will be analyzed to determine which invertebrate taxa salmon are consuming, and salmon muscle tissues will be analyzed for total percent lipid content, an important determinant of over-winter survival. Empirical data collected during this study also will be used in developing a bioenergetically based simulation model that will allow exploration and understanding of a more complete range of potential climate effects on juvenile coho salmon.

Expected Results:

Emergence timing is hypothesized to be under strong selection in salmonids and to be very sensitive to climate. Earlier salmon emergence is expected in streams with relatively warmer temperatures in the winter due to greater degree day accumulation for developing salmon eggs. Furthermore, in streams with less thermal variation, there should be strong selection for more synchronous emergence to match the most ideal timing of emergence. Thus, emergence should be less variable in more predictable systems. Juvenile salmon are critically dependent on the timing of prey availability. Thus, the timing of juvenile emergence may be strongly associated with greater prey availability. Climate change may create a phenological mismatch, in which case a predator becomes decoupled in time with its prey. This research will provide data about the potential for phenological decoupling to occur between Alaskan salmon and their invertebrate prey, which is likely given that these streams are particularly susceptible to climate change impacts.

Potential to Further Environmental/Human Health Protection

Salmon are of vital economic, ecological and cultural importance to human communities. Alaska is one of the last regions along the Pacific Northwest that still has salmon returns near historic levels, and yet this same region is predicted to show the greatest changes in climate. This study will provide novel data on climatic influence on salmon demography and phenology, which will be used to construct predictive climate models to best manage and protect future salmon.

Supplemental Keywords:

climate change, salmon, phenology

Progress and Final Reports:

  • 2015
  • Final