Top Stories From Homer, Alaska

Throughout the debate over restricting charter-caught halibut, charter fishermen raised the same point: Why does the charter fleet get targeted when more halibut is lost through bycatch mortality?

The answer has to do with management decisions for other fisheries that permit halibut bycatch as part of allowing economically important fisheries to exist.

According to the International Pacific Halibut Commission, in 2006, 12 million pounds of halibut were landed by the sport fishery while 12.1 million pounds were lost through bycatch, the taking and release of fish by other commercial fisheries, mainly groundfish trawl fisheries in the Bering Sea and Gulf of Alaska. Bycatch mortality was about 12 percent of the 95.5 million pounds of halibut taken in 2006 for all uses in Alaska, Canada and the Lower 48.

Most halibut bycatch comes from other fisheries, such as the trawl fishery and pot fishery, which under regulation have to discard halibut caught with other fish.

“The majority of bycatch is not a result of the halibut fishery,” said Bruce Leaman, executive director of the IPHC.

Most of the bycatch within the halibut fishery comes from lost or abandoned gear and the release of sublegal halibut. Halibut fishermen who catch fish under 32 inches have to discard them, said Jane DiCosimo, a fishery analyst with the North Pacific Fishery Management Council, the federal body that regulates species caught under the Magnuson-Stevens Act.

Fishermen targeting other species can buy halibut quota shares to allow them to keep legal-size, hook-caught halibut taken in other fisheries.

The NPFMC sets caps on halibut bycatch in the groundfish fishery as a whole, and then to each sector or fishery. To keep the bycatch cap from being exceeded, fisheries are opened and closed as needed.

“The council has a bigger responsibility. It doesn’t just manage halibut,” DiCosimo said. “It has to balance the needs of those other fishers.”

The council has to consider the loss of halibut to bycatch mortality against the economic benefit to other fisheries, she said.

Figures for 2006 halibut bycatch estimated by fishery and area show the degree of bycatch. According to the IPHC, in Area 3A, 2.3 million pounds of bycatch were from the groundfish trawl fishery, 250,000 pounds from the crab pot and shrimp trawl fishery, 197,000 pounds for cod and rockfish, and 119,000 pounds from the commercial sablefish fishery. That contrasts with 5.6 million pounds of bycatch from the groundfish trawl fishery in Area 4, the Bering Sea and Aleutian Islands districts. About 6.8 million pounds total bycatch was taken in Area 4.

DiCosimo said that number of 12.1 million pounds is for bycatch in all IPHC regulatory areas. For Southcentral Alaska, Area 3A, 2.9 million pounds of bycatch halibut were lost. Most bycatch is caught in Area 4.

Leaman noted that legal-size bycatch doesn’t affect other areas, but bycatch of sublegal halibut — halibut still maturing — can affect other areas, since those halibut migrate throughout the north Pacific Ocean. An immature halibut that dies in Area 4 could be a halibut that might have matured and moved into Area 3A.

The sport and commercial halibut fisheries also are responsible for some bycatch mortality. The IPHC monitors bycatch mortality among many commercial fisheries, including halibut longliners. Various studies have looked at factors like the kinds of hooks used.

A 1969 study of commercially caught halibut, “Viability of tagged Pacific halibut,” by G.J. Peltonen, suggested that mortality for J hook-caught halibut released in excellent condition ranged from 2 to 5 percent.

Gregg Williams, a fisheries biologist with the IPHC, said that the midpoint of that range, 3.5 percent, is better seen as a starting point to examine the question of bycatch mortality in the sport fishery.

The Alaska Department of Fish and Game has recently stated that mortality of bycatch for all circle-hook caught halibut taken in the sport fishery might be about 3.5 percent, said Scott Meyer, a fishery biologist with Fish and Game’s Homer office.

Offset circle hooks have become the hook most widely used in commercial and sport fisheries. Unlike the J-shaped hooks, circle hooks are hard for halibut to swallow deeply and usually get set in the lips. Offset circle hooks angle up when laid flat. The placement of a hook in the halibut’s mouth is the main criteria for mortality, Meyer said.

Sport-caught fish using circle hooks have a good chance of surviving if released. They’re usually fought for little time and smaller fish can be released easily, he said.

“We would expect to see a very low rate of mortality,” Meyer said.

Leaman noted that there’s some uncertainty about catch-and-release discard mortality in halibut sport fisheries. Some sport fishermen might not be as skilled at releasing hooked halibut as commercial fishermen and the percentage composition of circle vs. other hook types with higher mortality rates is not well known. No studies have been done comparing catch-and-release mortality between the recreational and guided-sport halibut fisheries.

Bycatch isn’t an allocation, Leaman said. For management purposes, it’s an amount taken off the available yields — the IPHC’s estimate of what’s available for harvest limit based on a percentage of the estimated biomass. It’s a reduction taken off the top, along with catches by halibut subsistence and sport fisheries.

“The commission’s perspective is that bycatch is always a target to reduce,” Leaman said.

Fisheries are looking at ways to reduce bycatch, such as developing gear that allows halibut to escape, or to put grids over ship holds to sort halibut so they can be released more quickly, DiCosimo said. The NPFMC also is looking at technology like vessel monitoring systems, such as video monitoring.

Leaman said Canadian fisheries have reduced halibut bycatch by more than half. The Canadian Department of Fisheries and Oceans in 1995 instituted an Individual Bycatch Quota for each trawl vessel along with 100 percent observer coverage. Once that quota for an area was reached, the ship had to quit fishing.

By 1997, bycatch mortality was reduced 85 percent, Leaman and Williams noted in a 2005 Marine Fisheries Review article.

In general, though, halibut bycatch mortality has decreased over the years, from a peak of 28 million pounds in 1965 to 12.1 million to 13.5 million pounds since 1997. Last year’s bycatch of 12.1 million was the lowest in the past 10 years.

Michael Armstrong can be reached at michael.armstrong@homernews.com.