Rocky Mountain Research Station

Title: Temporal variation in synchrony among chinook salmon (Oncorhynchus tshawytscha) redd counts from a wilderness area in central Idaho

Author: Isaak, D.J.; Thurow, R.F.; Rieman, B.E.; Dunham, J.B.

Date: 2003

Source: Canadian Journal of Fisheries and Aquatic Sciences 60:840-848.

Description: Metapopulation dynamics have emerged as a key consideration in conservation planning for salmonid fishes. Implicit to many models of spatially structured populations is a degree of synchrony, or correlation, among populations. We used a spatially and temporally extensive database of chinook salmon (Oncorhynchus tshawytscha) redd counts from a wilderness area in central Idaho to examine patterns in synchrony as these fish underwent a sixfold decrease in abundance. Our results suggested that populations became strongly synchronous as abundances decreased and that the range, or diversity of correlations, exhibited among populations also decreased. These changes indicate that the likelihood of simultaneous extirpations has increased, which could have long-term detrimental consequences for metapopulation persistence. Implications for management are that the resilience of many metapopulations to large-scale disturbance and anthropogenic suppression may not depend solely on attempts to maintain large and productive component populations, but also on efforts to desynchronize populations that have become strongly correlated. Such efforts could entail promoting the existence of a broad distribution and diversity of habitats that support a wide array of lifehistory forms and ensuring that some habitats are sufficiently spatially disjunct so that risks from catastrophic stochastic events are minimized.

Keywords: chinook salmon, salmonid fishes, populations, spatially and temporally extensive database

View and Print this Publication (300 K)

Publication Notes: 

• We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
• This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.

 Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility

Citation

Isaak, D.J.; Thurow, R.F.; Rieman, B.E.; Dunham, J.B.  2003.  Temporal variation in synchrony among chinook salmon (Oncorhynchus tshawytscha) redd counts from a wilderness area in central Idaho.   Canadian Journal of Fisheries and Aquatic Sciences 60:840-848. .