VANCOUVER -- Where commercial fishermen fish and the type of gear they fish with largely determines the amount of collateral damage done to the environment, according to a new national study being released today.

And that damage - from the destruction of rare coral reefs to the incidental killing of species that are accidentally taken as bycatch - has to be reduced, warn three marine conservation groups from Canada and the United States.

The groups undertook a study that examined the impact of 13 different gear types used by commercial fishermen across Canada, ranking the fishing methods according to the severity of their impact on the environment.

The report, How We Fish Matters, says changes in fishing methods are needed to end destructive practices and urges the government to speed up a marine-planning process so that sensitive areas can be protected before it's too late.

"We need to get our heads around this and figure out what it means to marine ecosystems," said Jennifer Lash, executive director of the Living Oceans Society, a British Columbia-based group that conducted the study along with the Ecology Action Centre of Nova Scotia and the Marine Conservation Biology Institute, based in Washington State.

The study, which included input from commercial fishermen, scientists, marine conservation professionals and fisheries managers, found most fisheries have an impact far beyond the specific species they target.

The report concludes that bottom trawling is the most destructive method of fishing, because of the swath of destruction it leaves on the sea floor, while the harpooning of North Atlantic swordfish is the least destructive because it affects only the target species.

Bottom gillnet fishing, in which a vertical net wall is anchored to the sea floor, and dredge fishing, in which metal baskets are dragged along the bottom to catch scallops, are almost as destructive as trawl fishing, while midwater trawling, longlines and midwater gillnetting rank in the middle. Purse seining, hook-and-line and diving, to collect species such as geoduck clams and scallops, are less destructive.

Bottom trawling, in which a large net held open by heavy metal doors is dragged along the sea floor, catching or killing almost everything in its path, is by far the most environmentally damaging fishing method, the report states.

Off the B.C. coast, the trawl fishery has been blamed for shattering rare glass-coral reefs found in Queen Charlotte Strait.

"We are worried about the deep-sea corals that are being destroyed. We know corals are being brought up. We have evidence of that from the bycatch data," Ms. Lash said.

She said there are also concerns about the bycatch in the trawl and other fisheries.

Although careful records are kept of the commercial species that are taken as bycatch, little is known about the non-commercial species, which are tossed back overboard.

"Say they are targeting rockfish but they catch sablefish. Sablefish is a marketable product and they [the Department of Fisheries and Oceans] have a plan in place to deal with that. What they don't have is a plan to deal with the discarded [non-commercial] bycatch, the starfish, the sea pens, all the other species that aren't eaten, and there's a huge amount of that being caught right now. But we don't really know what it means when we take all these starfish and sea pens out of the ecosystem," she said.

Ms. Lash said there needs to be a shift to less destructive fishing methods wherever possible.

"There are two ways we can get fishermen to switch gears. One is we need to only allow the more destructive fishing gear in areas where it has the least impact. ...The other thing we want to do is use a quota allocation, so if you are using less-harmful gear you would get more access to the fish," she said.

The report recommends that fisheries managers "immediately implement ecologically risk-averse strategies to minimize the impacts of fishing gear on habitat and bycatch."

The report also warns that as fish stocks fall on the Atlantic and Pacific coasts, commercial fishing pressure will increasingly shift to deeper waters, and into the Arctic where relatively little is known about the environmental damage that might result.

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How fishing methods can succeed or fail to catch their target species, and what damage they can cause to other species and the fragile ocean-floor ecosystem

HARPOON

Harpooning involves sighting a_swordfish that is basking or finning at the sea surface, then spearing it with a four- to five-metre-long harpoon attached to a line. The line is usually attached to a buoy or floating drum to allow the swordfish to tire before being hauled onboard._Harpoons are used only in Atlantic Canada.

HOOK AND LINE

These use a single hook or_only a few hooks on a line. Examples of hook-and-line fisheries include troll, jig,_handline and rod and reel.

PURSE SEINE

The purse seine employs large sections of net with floats along the top edge and weights along the net bottom. Purse seines are set in the water in a circle using a small boat called a skiff. Once the fish are encircled, the bottom_is pulled together to close_the net around the fish.

PELAGIC LONGLINE

Consists of a long "backline" from which thousands of smaller lines hang, each with a baited hook. The line is suspended in the water column by a series of floats. Mainlines are typically 64 kilometres long and baited with 1,000 to 3,000 hooks at a time.

BOTTOM GILLNET

Bottom gillnets hang vertically in the water column and catch fish in their mesh. Anchors or weights are attached to the gillnet, securing it to the sea floor. Bottom gillnets are used only in Atlantic Canada.

BOTTOM LONGLINE

This is a single mainline to which hundreds of shorter lines are attached armed with baited hooks. Anchors attached to the longline secure the gear to the ocean floor.

DREDGE

Scallop dredges consist of metal baskets that are dragged along the sea floor. A clam dredge uses a hydraulic jet to liquefy the sediment and then catches any solid objects in its path.

POT AND TRAP

Consists of retrievable_pots and traps, not_attached to the shoreline.

BOTTOM TRAWL

Bottom trawls consist of large nets dragged along the sea floor. The net may be held open by a pair of heavy metal doors (otter trawling) or by a beam (beam trawling). In Canada, beam trawling only occurs in the West Coast shrimp trawl fishery.

MIDWATER TRAWL

The midwater trawl is similar to the bottom trawl except it lacks rollers on the footrope, and has rectangular doors and a larger mesh in the mouth of the trawl. Midwater trawls are often fished near the sea floor.

IMPACT OF VARIOUS TACKLE TYPES

H=High

MH= Medium-high

M-Medium

ML=Medium-low impact

		HOOK	PURSE	PELAGIC	POT	MIDWATER	BOTTOM	DREDGE	BOTTOM	BOTTOM
	HARPOON	AND LINE	SEINE	LONGLINE	AND TRAP	TRAWL	LONGLINE		GILLNET	TRAWL
Invertebrates	ML	ML	ML	ML	M	ML	ML	H	M	H
Groundfish	ML	MH	ML	ML	M	MH	H	MH	H	H
Forage fish	ML	ML	MH	ML	ML	H	ML	ML	ML	MH
Sharks and	ML	ML	M	H	ML	M	M	ML	M	ML
Large Pelagics
Seabirds	ML	ML	ML	MH	ML	ML	M	ML	M	ML
Marine mammals	ML	ML	ML	M	M	ML	ML	ML	MH	ML
Corals and sponges	ML	ML	ML	ML	M	ML	MH	H	MH	H
Seafloor	ML	ML	ML	ML	ML	ML	ML	H	ML	H

TONIA COWAN/THE GLOBE AND MAIL; SOURCE: HOW WE FISH MATTERS, A REPORT FROM THE ECOLOGY ACTION CENTRE, LIVING OCEANS SOCIETY, AND MARINE CONSERVATION BIOLOGY INSTITUTE