DOI: 10.24431/rw1k21i
title: Tracking Seasonal Movements of Adult Pacific Herring in Prince William Sound, 2012-2016, EVOS Herring Program. Ocean Tracking Array Expansion 2016.

description: Tracking Seasonal Movements of Adult Pacific Herring in Prince William Sound, 2012-2016, EVOS Herring Program

These data are part of the Herring Research and Monitoring Program of the Exxon Valdez Oil Spill Trustee Council, which is a multi-faceted study to determine why herring populations in Prince William Sound remain depressed since the early 1990s.

In Prince William Sound (PWS) adult herring disperse after spawning, however their movement patterns are poorly understood. Acoustic telemetry is a tool used to track fish to understand more about their seasonal movements. This project (EVOS project numbers: 12120111-B, 13120111-B, 14120111-B) tested the utility of acoustic tags for tracking the seasonal migrations of adult herring into and out of PWS. In April 2012 and 2013 adult herring were captured on their spawning grounds in Port Gravina (northeast PWS) using jigs. The herring were then sedated, measured and a small acoustic tag surgically implanted. In 2012 25 herring were acoustically tagged, and 69 herring were tagged in 2013. 

Post release tagged herring were monitored by acoustic receiver arrays with two receivers located near the entrance to Port Gravina (on the eastern and western side) through 19 May 2012, when data was uploaded. In 2013, coverage in Port Gravina was expanded and included an array of nine receivers. Receivers were deployed in Port Gravina from 7-8 April through 21 May 2013 when receivers were removed. As part of the Ocean Tracking network (www.oceantrackingnetwork.org), receiver arrays were also deployed across the principal entrances into the Sound from the Gulf of Alaska during March 2013. Arrays were located at Hinchinbrook Entrance, Montague Strait, and the four southwest passages in Prince William Sound. Data from the Ocean Tracking Network arrays were uploaded in February and May 2014, after transmitters had expired. Tag life on transmitters was estimated at ~ 263 days. 

This dataset contains four comma-separated values (csv) files each containing the tagging log and acoustic receiver detection log for each tagging year (e.g. 2012 and 2013). The files named 'Herring Tagging Log' describe the length and weight measurements and spawning-state characteristics for each acoustic tagged fish. The files named 'AcousticTaggedHerringDetections' are acoustic receiver detection logs containing the data, time, and location of tagged herring detections.

Ocean Tracking Network Array Expansion, 2016

In 2013, we documented post-spawn migration of herring from Port Gravina to the PWS entrances by acoustic tagging adult herring and collecting data from the Ocean Tracking Network acoustic arrays. The 2013 study, however, could not verify if herring were migrating out into the Gulf of Alaska (GOA) and then returning to PWS because of the single-line layout of the Ocean Tracking Network arrays. 
 
The February 2017 acoustic array expansion created a double-line of receivers in known areas of high traffic by herring at the Ocean Tracking Network. This will allow PWSSC researchers to document adult herring migration movements out from and into PWS, and to better understand factors that influence migration patterns including age, condition, spawning location, and residency in PWS. 

The dataset contains one csv file containing array location, station name, deploy latitude, deploy longitude, and deploy depth for the receivers deployed during February 2017 as part of project 16160111-S.