Project Information

Title: HRM Program: Validation of Acoustic Surveys 15120111-A

Project Year and Number: 2015: 15120111-A

Other Fiscal Years and Numbers for this Project: 2016: 16120111-A, 2014: 14120111-A, 2013: 13120111-A, 2012: 12120111-A

Principal Investigator (PI): Mary Anne Bishop

Managing Agency: NOAA

Assisting Personnel: None

Project Website: https://pwssc.org/herring/

Research Location: Prince William Sound

Restoration Category: Monitoring

Injured Resources Addressed: Pacific Herring

Abstract:

Acoustic surveys provide a relatively low-cost, remote sensing tool to estimate species-specific fish biomass and abundance. Interpreting acoustic data requires accurate ground truthing of acoustic backscatter to confirm species and length frequency of insonified targets. Since November 2012, juvenile and adult herring acoustic surveys have been conducted in November and late March, respectively. Pelagic trawls are the recommended method for validating species composition and for obtaining relatively unbiased information on length frequency distribution, age, and other biological information. Here we propose to use a low-resistance, light-weight midwater sweeper trawl capable of towing speeds (up to 3 knots) as a method to ground truth acoustic surveys for juvenile herring. Our pelagic trawl surveys will take place in conjunction with and onboard the same vessel as three studies in the PWS Herring Research and Monitoring program: a) Juvenile Herring Abundance Index (years 2-5); b) Acoustic Consistency: Intensive Surveys of Juvenile Herring (year 3). Because of concerns of the Alaska Department of Fish and Game, for the March Expanded Adult Herring Surveys (years 2-5) we are being required to use gillnets and jigging for validation. Our project will provide data on species composition and length frequency to aid in the interpretation of current and historical acoustic surveys. In addition it will provide adult herring samples to Alaska Department of Fish and Game for the adult herring age-structure-analyses model and will provide juvenile herring samples to researchers investigating juvenile herring fitness and disease. Our trawls will also provide fishery-independent surveys for non-herring species, thus increasing our knowledge of pelagic fishes in Prince William Sound.


Proposal: View (45 KB)

Reports:
Annual Report FY15: View (536 KB)
Final Report: See Project 16120111-A

Publications from this Project: None Available