Abstract Title

Session S-08D: Salmon Recovery: Implementation and Progress I

Proposed Abstract Title

Trophic distress of juvenile salmon in Johnstone/Queen Charlotte Strait?

Presenter/Author Information

Brian BeckmanFollow

Keywords

Species and Food Webs

Location

Room 6C

Start Date

1-5-2014 5:00 PM

End Date

1-5-2014 6:30 PM

Description

Johnstone Strait and Queen Charlotte Strait are situated between the northern end of Vancouver Island and the British Columbia mainland, connecting the Strait of Georgia to Queen Charlotte Sound. For juvenile salmon, this area provides a migratory corridor between initial marine rearing areas in the Strait of Georgia to Queen Charlotte Sound and the Gulf of Alaska. Tidal mixing homogenizes the water column in the narrow passages of this region, creating both an unstable water column with relatively low primary productivity and dissipation of any zooplankton or juvenile fish patches. McKinnell et al. (in review) have suggested that this region represents a trophic challenge for juvenile salmon, as food is scarce and fish must transit this region to reach more favorable marine feeding grounds. They term this challenge the “Trophic gauntlet hypothesis”. We will present plasma insulin-like growth factor 1 (IGF1) data for juvenile salmon (coho, sockeye, chum, Chinook and pink) collected opportunistically in Queen Charlotte Sound, Queen Charlotte Strait, Johnstone Strait or the Strait of Georgia between 2009 - 2013. IGF1 is a hormone that is an index of the relative growth of fish. The trophic gauntlet hypothesis will be exposed to these data as we report on growth of juvenile salmon in Strait of Georgia, before they enter Johnstone Strait; in Johnstone Strait, the putative zone of deprivation; and then from Queen Charlotte Sound, after fish have presumably reached richer feeding grounds. Results from this challenge of the trophic gauntlet hypothesis may result in more directed studies of the marine ecology of juvenile salmon as they migrate through this region.

This document is currently not available here.

Share

COinS
 
May 1st, 5:00 PM May 1st, 6:30 PM

Trophic distress of juvenile salmon in Johnstone/Queen Charlotte Strait?

Room 6C

Johnstone Strait and Queen Charlotte Strait are situated between the northern end of Vancouver Island and the British Columbia mainland, connecting the Strait of Georgia to Queen Charlotte Sound. For juvenile salmon, this area provides a migratory corridor between initial marine rearing areas in the Strait of Georgia to Queen Charlotte Sound and the Gulf of Alaska. Tidal mixing homogenizes the water column in the narrow passages of this region, creating both an unstable water column with relatively low primary productivity and dissipation of any zooplankton or juvenile fish patches. McKinnell et al. (in review) have suggested that this region represents a trophic challenge for juvenile salmon, as food is scarce and fish must transit this region to reach more favorable marine feeding grounds. They term this challenge the “Trophic gauntlet hypothesis”. We will present plasma insulin-like growth factor 1 (IGF1) data for juvenile salmon (coho, sockeye, chum, Chinook and pink) collected opportunistically in Queen Charlotte Sound, Queen Charlotte Strait, Johnstone Strait or the Strait of Georgia between 2009 - 2013. IGF1 is a hormone that is an index of the relative growth of fish. The trophic gauntlet hypothesis will be exposed to these data as we report on growth of juvenile salmon in Strait of Georgia, before they enter Johnstone Strait; in Johnstone Strait, the putative zone of deprivation; and then from Queen Charlotte Sound, after fish have presumably reached richer feeding grounds. Results from this challenge of the trophic gauntlet hypothesis may result in more directed studies of the marine ecology of juvenile salmon as they migrate through this region.