For more information on species & ecosystem science:

Wildlife Science
360-902-2515
wildthing@dfw.wa.gov

Fish Science
360-902-2700
fishpgm@dfw.wa.gov

Habitat Science
360-902-2534
habitatprogram@dfw.wa.gov

 
 

Lead Scientist: Theresa Tsou

Ecoregions: Pacific Northwest Coast

   
 
   
 

Marine Fish Monitoring

Coastal Rockfish Tagging

Project Description

Black rockfish (Sebastes melanops) are widely distributed along the Pacific coast from central California to the Gulf of Alaska inhabiting nearshore areas at bottom depths of less than 50 fathoms.  Large schools of adult fish tend to be attracted to irregular, rocky bottom habitat or other underwater structures, although it is not unusual to find them actively feeding on the surface.

Recreational and commercial fishers have harvested black rockfish in nearshore areas off the Washington coast and in Puget Sound since the early 1940’s.  However, concern for declining populations has resulted in increasingly restrictive regulations for commercial fisheries, such as closing the ocean inside three miles (state waters) to all commercial groundfish gear. As a result, commercial black rockfish landings have steadily declined to negligible levels since the mid 1980’s. Black rockfish, however, remain an important natural resource to the recreational fisheries that coastal communities rely upon for a vital economy. Due to the importance of this resource, WDFW and coastal recreational charter boat fleets have been collaborating on tagging projects for the conservation of black rockfish and other coastal groundfish species.

In Washington, the first black rockfish tagging project began in 1981.  Back then little was known regarding the life history of the black rockfish. Consequently, the early tagging work concentrated on gathering biological information, such as movement and growth.  Over the intervening years, the project has undergone changes as study objectives were re-defined and improvements in tagging protocols were made.  The overall objective of this program is to produce estimates of black rockfish abundance, growth, survival, and mortality. These statistics are then incorporated into population models for coastal black rockfish used by fishery managers.

To collect this scientific information requires tagging thousands of rockfish annually. Most tagging trips depart from Westport, Washington but many trips also originate from Ilwaco, La Push and Neah Bay. During a typical tagging trip, 10 to 12 volunteer anglers are tasked with catching rockfish - as many as possible.  WDFW biologists and technicians then scan the rockfish to detect previously placed tags and collect biological data. If no tag is detected, the fish is tagged using a PIT (Passive Integration Transponder) tag similar to the kind used for pets. The tag number is recorded electronically and again biological data are collected.  Processing time, from the time a fish is brought onboard, tagged, measured and released, is about 15 seconds. When necessary, a live-well is utilized to fully recover fish prior to release.  Eventually, tagged fish are caught by anglers onboard charter vessels and private recreational vessels. The charter vessels deliver the carcasses to port where technicians scan them for tags. Over the years, millions of carcasses have been screened for the presence of these tags and from these recoveries we have learned more about black rockfish abundance, seasonal distribution and migration patterns. 

Publications

Staff

  • Lorna Wargo
  • Brad Speidel
  • John Pahutski
  • Michael Sinclair

More Information

Volunteer Opportunities