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Open Water:
The Monterey bay/Marine Canyon
pelagic shark tagging project:

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Once a subject shark of the proper specifications has been lured to the boat it is drawn close by using a fresh salmon or tuna head fascine with monofilament line as bait. As the shark attempts to grab hold of the bait it can be brought right along side the boat where it can be scooped up in a long handled sport fishing net. A practiced crew can scoop, land, sample/tag and release sharks up to 2 meters TL in less than 4 minutes.

Once aboard, the subject animals are carefully removed from the scoop-net and restrained. Once the sharks has been properly arrested and restrained it can be quickly measured for total length (TL), sampled for tissue or blood, tagged or attached with a transmitter and then released. The procedure should never take longer than 4 minutes.

Things to consider: Plan out each capture and intended arrest procedure and sample assignment, be organized. Shade for the animal’s eyes on bright days will reduce unruly behaviors, alternately; the use of a ‘bit’ or something like a towel for the shark to bite on can assist in handling procedure, and this is often useful for larger sharks. The scoop- net method should not be attempted with animals larger than the researchers involved.

The larger the shark the more likely it is inflict and/or sustain damage due to capability to powerfully struggle. While the fragility of sharks (while out of water) is overstated it is very important that hard contacts and blows to the head, gills and body cavity be minimized. A towel can be used to both shade the eyes, occupy the jaws while serving as both a carry handle as well as a crash helmet for the unruly shark. Upon allowing the shark to bite down on a wadded end of a towel, the animal will often twist around and wrap its head in the towel. This wrapped towel can help put the business end of the shark out of commission and provide a grab-hold.

This procedure greatly reduces stresses and injury compared with conventional hook and line collecting. Long-lining and sport angling can injure or impair the subject sharks; all things considered sharks are very resilient and can often weather very rough treatment at the hands of commercial and sport-fisherman or research hook/line operators and some remarkable tag recoveries have been gathered using conventional methods. We are convinced that innovative PSRF collecting and sampling methods significantly exclude typical injuries associated with tag and release efforts.

The PSRF open-water project has tallied over 1500 blue, Shortfin mako and common thresher sharks within the Monterey Bay since 1990; earlier preliminary work was conducted over the Monterey Marine Canyon by Sean Van Sommeran beginning in 1989.

Sharks tagged within the Monterey Bay have been recovered from Dana Point California and the Channel Islands, off the coast of Baja Mexico. One blue shark tagged by PSRF staffers during the summer of 2000 was recovered less than 600 miles off the coast of Japan by a commercial long-lining vessel.

The very lucrative ‘shark-fin trade’ has virtually eliminated the ‘bycatch’ category for blue sharks as all sharks caught by the vast open sea fleets are finned and killed off.

The ‘shark-fin trade’ is a very shady and under the table market with well known but underplayed connections to organized crime that have actually resulted in numerous armed robberies, heists, and shootings in Central America, California, South Africa and elsewhere.

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