Past Awards

FY 2006 | 1 – Understand | 6/10/05

Biological Monitoring of Spring Zooplankton and Nekton in PWS

Richard Thorne, Prince William Sound Science Center
Contract Term: 01/01/06-12/31/06
Award: $75,000

Scope of Work:

This project was initiated in 2000 with the overall goal to develop and apply a cost effective approach to the estimation of the pink salmon food supply and predator abundance. The specific objectives are to measure the abundance of zooplankton as food supply for juvenile pink salmon and the abundance of predators. Pink salmon were a major impacted species by the Exxon Valdez Oil Spill. Accurate forecasting of adult returns has been lacking and is critical to the economics of the Cordova community. Field work consists of three spring-period cruises (late April to early June) of 4-day length that cover the main basin of PWS and Knight Island/Perry Island Passages. Measurements include multi-frequency acoustic backscattering and plankton net tows (typically 12 per cruise) to measure abundance of both plankton and fish in PWS. The results have shown strong correlations between pink salmon survival and the abundance of large zooplankton, particularly large-bodied copepods, and are increasingly providing predictive capability.