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A cooperative effort to track the Humboldt squid invasion in Oregon
A cooperative effort to track the Humboldt Squid invasion in Oregon<br />Selina Heppell and Sarikka Attoe<br />Research Plan<br />2010-2012<br />
The problem<br />Humboldt Squid (Dosidicus gigas aka Jumbo Squid) have experienced a dramatic range expansion<br />“Native Range” = south of Point Conception, CA<br />New Range = all the way to Alaska in some years<br />They are large (>1m) predators that can consume large prey items<br />
The problem<br />Light gray shows native range<br />Darker grays show expanded range<br />Expansion to south mirrors ours in the north, but earlier?<br />
Why has the range of Humboldt Squid expanded so drastically?<br />Theories:<br />Climate change<br />El Niňo events always resulted in temporary range expansions<br />After the 2002 El Niňo the squid populations have persisted in their new range<br />Shifts in the food web<br />Common prey = sardine, also more common in north lately<br />Overfishing of competitors and predators of juveniles?<br />http://envirocation.files.wordpress.com/2009/07/humboldt-squid.jpg<br />
What are they eating in their new range?<br />No one knows<br />Are they breeding in their new range?<br />No one knows<br />Is someone eating them?<br />No one knows<br />
Why do we care?<br />Commercial and recreational fishing are very important to the state of Oregon<br />Fishermen are pulling up target species with Squid actively eating the target species (for instance salmon)<br />High profile species: beach strandings, recreational fishing, Discovery Channel<br />Invasive? Indicators of climate change?<br />
Diet<br />Hake = major prey item<br />Indications of negative impacts of squid in Chile<br />
Cooperative Research<br />Goal: To determine the extent of jumbo squid in Oregon, correlations between catches and oceanographic variables, and prey composition within that range. <br />
Research Plan<br />Interview fisherman and research historical catch information to determine where squid have been present and under what conditions.<br />Work with tuna, salmon, and charter fishermen to collect samples of jumbo squidin areas typically fished by the commercial and recreational industries.<br />Determine diet.<br />Create a GIS map of reported catches and CPUE.<br />Determine if squid are breeding.<br />Inform industry and the general public.<br />
Diet analysis<br />Squid don’t always swallow prey whole!<br />Dissect stomachs<br />ID hard parts or large identifiable chunks of prey<br />DNA analysis of unidentifiable chunks of prey<br />Evaluate presence/absence, relative occurrence of different prey types in time and space<br />Compare to California and other parts of the jumbo squid range <br />
Public Outreach .<br />Squid Cook Off<br />Get to know how delicious this invader tastes!<br />Display at Hatfield Visitor Center<br />Including a preserved squid!<br />Short Documentary with Oregon SeaGrant<br />Target fishermen and interested public<br />
So what?<br />We will find out if the squid are feeding on key species, and their potential impact on Oregon fisheries<br />We will find out if the squid are breeding in Oregon or if they just move up there to eat<br />We will inform the public about the range expansion<br />We will inform efforts to establish Humboldt Squid as a new fishery in our area<br />
Collaborators<br />Bill Hanshumaker and Oregon Sea Grant<br />Tuna and <br />salmon fishermen<br />Dr. William Gilly,<br /> Stanford<br />Dr. John Field,<br /> SW Fisheries<br />Science Center<br />