Sea lice are spreading. Is the government noticing?

By Stephen Hume

Vancouver Sun
January 23, 2008

Sea lice infestations affecting wild salmon smolts that migrate past fish farms have been found in yet another region of British Columbia’s remote coast.

The problem poses potential headaches for the provincial government, since it suggests implications for commercial and recreational fisheries worth close to $1 billion a year, scientific research indicates.

“Sea lice infestations of wild juvenile fish in Pacific Canada extends beyond juvenile pink and chum salmon in the Broughton Archipelago to juvenile pink, chum and sockeye salmon, as well as larval herring in the Discovery Islands,” scientists say in a paper to be published in April by the North American Journal of Fisheries Management.

The islands are about 200 kilometres from Vancouver at the northwest end of the Strait of Georgia.

Authors are Martin Krkosek of the Centre for Mathematical Biology at the University of Alberta, Rich Routledge from the Department of Statistics and Actuarial Science at Simon Fraser University and biologist Alexandra Morton, who operates a research station at Simoom Sound off northern Vancouver Island.

Meanwhile, a fisheries biologist conducting research in the area for the Xwemalkhwu First Nation reports similar findings, although he stresses results are preliminary and not yet peer-reviewed.

“At least a third of the juvenile sockeye we sampled are infected,” says Mike Price of the Raincoast Conservation Foundation. He’d like the province to do genetic analysis to determine the origin of the infected sockeye samples. “Are they from the Fraser River? If this is not a Broughton specific problem, how prevalent is it? We don’t know what’s happening in Clayoquot Sound, in Kyuquot Sound, in any of these places we are not monitoring,” Price says.

The effects of sea lice infestations upon wild fish have been a source of controversy since pink salmon runs passing salmon farms in the Broughton Archipelago collapsed in 2002. A study published in the journal Science in December 2007 predicted that if sea lice infestations were not curbed, those runs would be extinct by 2012. Krkosek, Morton and four other scientists from the U of A and Dalhousie University wrote that paper.

Industry and both federal and provincial governments, which have vigorously promoted the development of salmon farms, have played down the effects of sea lice upon wild salmon stocks. Pink declines in the Broughton are part of a natural cycle and are rebounding naturally, it’s been argued.

However, the discovery that sockeye smolts and immature herring so young they have yet to develop scales are also being preyed upon by sea lice in a crucial migratory choke point is a scientific surprise that seems certain to get a lot of attention. Herring provide both a valuable commercial harvest and a crucial food source for other species, including mature coho and Chinook which are the mainstay of the province’s recreational salmon fishery.

“Sea lice on juvenile herring are unreported for the Pacific and extremely rare in the Atlantic,” the peer-reviewed paper observes. “Together, Fraser sockeye and Strait of Georgia herring are British Columbia’s most important commercial fish stocks.” In testimony before the Senate fisheries committee on Oct. 24, 2005, the Sport Fishing Institute of B.C. estimated that recreational tidal fishing, most of it directed at salmon, created 7,240 jobs and generated $400 million a year in boat, equipment, tackle and accommodation rental alone.

It estimated total value of tidal recreational fishing at around $625 million. Provincial figures in 2006 show the wholesale value — that’s after processing — of commercially caught wild salmon at $227.6 million, of which $113.6 million derived from sockeye. The commercial herring fishery generated $58.8 million in wholesale value.

Sport angling remains a mainstay of province’s tourist economy from elite fly-in lodges to places like Campbell River, adjacent to the Discovery Islands. The community, which is also a major fish farming centre, still bills itself the salmon fishing capital of the world.

Since 1924, members of its internationally-renowned Tyee Club have trolled from small, hand-rowed boats for Chinooks weighing 30 kilograms or more. Provincewide statistics show that anglers bought 338,000 tidal waters licences in 2002 and spent a total of 2.1 million days in actual fishing in B.C.

That sounds like a lot of potentially disgruntled voters to me. Government might be wise to take note of this research.

shume@islandnet.com
The Vancouver Sun 2008

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