Project Information

Title: HRM Program: Expanded Adult Herring Surveys 16120111-E

Project Year and Number: 2016: 16120111-E

Other Fiscal Years and Numbers for this Project: 2021: 21120111-G, 2020: 20120111-G, 2019: 19120111-G, 2018: 18120111-G, 2017: 17120111-G, 2015: 15120111-E, 2014: 14120111-E, 2013: 13120111-E, 2012: 12120111-E

Principal Investigator (PI): Pete Rand

Managing Agency: NOAA

Assisting Personnel: None

Project Website: https://pwssc.org/adult-biomass-surveys/

Research Location: Prince William Sound

Restoration Category: Monitoring

Injured Resources Addressed: Pacific Herring

Abstract:

Prince William Sound herring stock biomass estimates from hydroacoustic surveys provide a direct measure of the stock abundance and are also a primary input into the age-structured assessment (ASA) model that is the forecasting tool used for managment. Prior to 2001, the hydroacoustic surveys were conducted exclusively by the Prince William Sound Science Center (PWSSC). Since 2001, the effort has been shared between PWSSC and the Cordova office of Alaska Department of Fish and Game (ADF&G). While the ADF&G considers the hydroacoustic surveys to be critical (Steve Moffitt, personal communication) the lack of a commercial herring fishery in PWS since 1998 has reduced management priorities for herring. Thus the PWSSC contribution has become critically important for the long-term, especially if a future fishery appears only a remote possibility. With the level of effort available over the past several years, PWSSC and ADF&G individually have achieved herring biomass estimates with a precision of about ±30%, which is insufficient for management purposes. However, the combined effort currently meets management requirements for precision. Current stock assessment efforts by ADF&G resource managers in PWS focus on the largest spawning aggregations. The objective of this study is to increase the current survey area of adult spawning beyond the Port Gravina and Fidalgo areas to provide a more precise estimate of spawning biomass. We propose to extend the PWSSC acoustic surveys to help identify the relative contributions of additional spawning aggregations over temporal and spatial scales. This will help establish more accurate estimates of the total herring biomass in PWS and provide an alert to changes in biomass in different regions. Beginning in FY2013 and continuing until 2016, hydroacoustic surveys will be conducted in late spring (April-May) to assess adult spawning biomass. ADF&G will continue to conduct direct sampling for age/length/weight. Additional direct capture will be conducted using a midwater trawl at adult spawning sites (See Bishop proposal).


Proposal: View (63 KB)

Reports:
Final Report: View (1,224 KB)

Publications from this Project: None Available