Project Information

Title: An Ecosystem Model of Prince William Sound Herring: A Management & Restoration Tool 070810

Project Year and Number: 2007: 070810

Other Fiscal Years and Numbers for this Project: None

Principal Investigator (PI): Dale Kiefer (University of Southern California)

Managing Agency: NOAA

Assisting Personnel: Evelyn Brown, Frank O'Brien, Vardis Tsontos

Research Location: Analysis/Modeling of data from Prince William Sound & Gulf of Alaska

Restoration Category: General Restoration

Injured Resources Addressed: Pacific Herring

Abstract: Over a three-year period, we propose to develop a life-stage specific, ecosystem based model of the Prince William Sound (PWS) herring that will aid in the integration of ecological data that has been gathered on herring over the last 2 decades, evaluation of proposed restoration activities, and attempt to simulation of the processes that cause the chronic decrease in herring stocks since the 1989 spill. More specifically, it will be used to test the unresolved hypotheses of why the herring have not recovered to pre-spill densities. The model and associated data will be housed in a geographic information system that we have developed specifically for marine applications. The geo-spatial information from field surveys and simulations with the model will available for interactive viewing and downloading of files over the Internet. The model will provide a mathematical description of the population dynamics of annual herring cohorts as they mature through their life stages. In particular we will focus on arrival of larvae to the Bays of PWS, the maturation and survival of juveniles in these bays, and the survival and reproductive success of adults as they move seasonally from spawning grounds, feeding grounds and wintering grounds. The system of coupled differential equations that describe these processes will be tuned to prove a best fit between model calculations and field and laboratory measurements. In its final form the model will consist of 3 sets of such equations that will simulate the unique conditions found in herring habitats of the eastern, northern and southwestern regions of PWS. Most importantly, the model will be formulated according to the principals of the trophic trap in which 2 metastable states for herring exist, low-density and high-density. We propose that a sequence of events following the spill drove the herring from high-density to low-density and a trophic trap prevents stocks from recovering. Thus, we will tune our model to both high-density and low-density states and then run the tuned models in the forward or backward direction to identify both the most probable causes of the injury and the most promising approaches to restoration. Our team has the scientific and technical experience to succeed, and we will work closely with researchers from the other herring projects, especially those working on larval drift, disease, otolith marking, and intervention. Our web-based system will promote such collaboration particularly with such groups as PWSFRAP and with the PWS Science Center.


Proposal: View (572 KB)

Information and/or Products produced by this project:
Title Description Type Document(s)
Quarterly Newsletter Additional Report View (297 KB)

Reports:
Annual Report FY07: View (432 KB)
Annual Report FY08: View (469 KB)
Annual Report FY09: View (318 KB)
Final Report: Not available. For current status, please contact us.

Publications from this Project: None Available