Q&A With San Juans Lingcod Researcher Reveals Species’ Patterns
APRIL 24, 2008—A researcher is asking anglers to report any tagged lingcod they catch in the San Juan Channel this season.
Anne Beaudreau of the University of Washington’s School of Aquatic and Fishery Sciences is studying the tasty bottomfish’s seasonal migrations as well as trying to figure out whether marine reserves between San Juan and Orcas, Shaw and Lopez islands “will protect and enhance lingcod populations to ultimately provide improved fishing opportunities outside the reserve boundaries.”
Beaudreau has outfitted many lings with “gray plastic spaghetti tags” near their dorsal fins. She is asking that you record the tag number; date and time you caught the fish; as specific of a catch location as possible (i.e., latitude and longitude, or place name); and the ling’s length and/or weight.
Ling season in Marine Area 7 runs May 1-June 15, with a daily limit of one fish from 26 to 40 inches. (Spearfishing season is May 21-June 15, with no minimum or maximum size, but a daily limit of one).
Phone or email Beaudreau your report at (206) 221-5458 and
annebeau@u.washington.edu.
The hot topic of more marine reserves in the Juans aside, we asked Ms. Beaudreau a little more about her project, which she says began almost five years ago. Last summer, she tagged more than 300 fish in the area, and put transmitters in some as well.
ANNE BEAUDREAU: During the summer 2007, I surgically implanted acoustic transmitters into nine lingcod in the marine reserve, which is closed to bottomfishing, on San Juan Island (between Friday Harbor Laboratories and Point Caution) and tracked their movements over three months.
I found that lingcod showed a lot of individual variation in their behaviors, and all except one never left the reserve during the summer.
Overall, fish tended to have “home” areas where they would remain stationary for several hours at a time.
Depending on light and tidal conditions, they would move deeper or shallower and then return to their home sites.
A single male lingcod made regular excursions every four or five days from the nearshore (20- to 30-meter depth) to the middle of the San Juan Channel (160-meter depth) and back, presumably for feeding.
Several individuals were regularly found moving within nearshore areas as shallow as 2 meters!
(Editor’s note: 1 meter equals 3.28 feet).
A related research question is whether lingcod make seasonal movements that differ from their small-scale daily activities. To address this question, I started tagging lingcod with the external plastic spaghetti tags during summer 2007 and have made follow-up trips to tag and recapture fish in November and February. May will be my last sampling trip.
F&H NEWS: In your five years of research, what can you say about your findings so far? Anything unusual or interesting or that sport anglers might not know or realize about the species?
ANNE BEAUDREAU: Most of my work so far has been related to the feeding habits of lingcod. I use a non-lethal technique called gastric lavage (a.k.a. stomach pumping!) to retrieve lingcod stomach contents and have found that they recover extremely well from this procedure.
Since 2004, I’ve collected stomach contents from nearly 900 lingcod in the San Juan Islands. This won’t come as a surprise to anglers, but lingcod pretty much eat anything that moves and that they can fit into their mouths. Their diets are made up of sculpins, rockfish, herring, sandlance, flatfish, greenlings, lingcod, gunnels, octopus, squid and a variety of other small fishes.
I’ve even pulled a 50-centimeter dogfish from the stomach of a lingcod that was over 1 meter long!
(Editor’s note: 50 cm equals just under 20 inches.)
Through my research, I’m trying to determine the impact of lingcod predation on rockfish populations, which have been at low levels in the San Juans for some time. Are lingcod eating enough rockfish to prevent them from recovering?
My work has shown that lingcod are eating mostly small rockfish, including Puget Sound rockfish (a small species that isn’t fished for) and juveniles of other rockfish species, including copper rockfish. I have also discovered that lingcod may be eating five to 10 times more rockfish in marine reserves than in the surrounding non-reserve areas. Without more information on rockfish sizes and numbers in these areas, it is hard to say what effect lingcod are having.
F&H NEWS: Sounds like a dream job — fishing for lingcod in the Juans! But how will you be going about it — hook and line? Diving? Other method? Any insight on what sort of bait you’ll be using, if it’s hook and line?
ANNE BEAUDREAU: It has been an incredible experience. I love fishing for lingcod, and all the fish have been collected by hook and line.
Because of the diet study, I couldn’t use bait. I keep it simple — 2- to 3-ounce leadhead jigs with plastic single- or double-tail worms. In terms of lure color, I’ve found that black, brown and motor oil work the best.
F&H NEWS: What do you think tagging the 300 or so (what was the average length and weight and catch location?) and recapturing them this year will tell you?
ANNE BEAUDREAU: It’s surprising, but we still know very little about lingcod populations in the Puget Sound area. It’s thought that they have recovered from low abundances in the 1970s and ’80s, but there is little current information about their abundance and distribution in this region. Through our tag recapture data in the San Juan Channel, I’m hoping to gain a better understanding of population size and structure at different sites.
I have six main sites in the San Juan Channel: two marine reserves on San Juan Island and Shaw Island and four non-reserve areas between Pear Point and Point Caution. The fish we’ve caught ranged in size from 30 centimeters (0.2 kg) to 115 centimeters (15.5 kg).
(Editor’s note: 1 kilogram equals 2.2 pounds.)
I believe that marine reserves are working well for lingcod. Our catch rates are higher in the protected areas and there are many more large females. My hope is that through reproduction, lingcod inside the marine reserves might provide a source of new recruits to surrounding areas that are open to fishing.
— Andy Walgamott
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