Tuesday, January 28, 2014

Bluefin Tuna Tag Recoveries

Captain Al Anderson, a charter boat captain out of Point Judith, Rhode Island, participates in the NOAA Fisheries Cooperative Tagging Program. One Capt. Anderson's tagged bluefin tuna was recently recaptured after 16 years.

That bluefin weighed a mere 14 pounds when Anderson caught it in the Mudhole east/southeast of Block Island in 1997. When a Nova Scotia fisherman recaptured it late last year, it weighed more than 1,200 pounds.

Anderson started tagging 45 years ago when he was a graduate student in fisheries biology at the University of Rhode Island.

Bluefin tuna that Anderson tagged have been recaptured off the coasts of Turkey and France. Anderson once recaptured a bluefin off Rhode Island that had been tagged ten days earlier near New Orleans, at least 1,600 miles away.

Over the years, Anderson and his charter clients have tagged tens of thousands of striped bass, almost five thousand bluefin, and 1500 sharks.

NOAA provides fishermen with tags to put on fish they catch and release, including highly migratory species like tunas, sailfish, and marlin. After tagging a fish, they send the tag number to NOAA Fisheries, along with date, location, length and weight.

If the fish is recaptured, the fisherman can read the number and call it in. That allows scientists to track migration patterns and estimate growth and mortality rates for these species.

Conventional tags provide snapshots of data when the fish is tagged and again when it’s recaptured. For a more detailed picture, scientists also deploy PSATs— pop-up satellite archival tags.

Pop-up satellite archival tags provide a huge amount of data on habitat preference, movement, and diving behavior, but because they’re costly there’s only so many of them.

Conventional tags provide less data per tag, but fishermen with the Cooperative Tagging Program have put them on roughly 270,000 fish of almost 80 different species since the program began in 1954.

More Information

Fishermen and tournament operators can get free tags and tagging kits by contacting NOAA’s Cooperative Tagging Center: http://www.sefsc.noaa.gov/species/fish/tagging.htm

source: NOAA Fisheries

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