Research on the survival of Wolffish out of water
Learn more about the Atlantic wolffish.
Transcript
Fishing on the coast of Newfoundland and Labrador... Catching cod and crab, shrimp, turbot, redfish, and sometimes pulling aboard fish you don't want to see.
Here's one now, a wolffish. The wolffish, cat-fish to most fishermen.
Not the prettiest fish in the sea for sure, and look at those teeth!
Why then is the government of Canada so concerned about the wolffish?
Why are they protected by law?
Why are fishermen being asked to carefully release any wolffish they accidentally catch?
Well basically because studies have shown that the wolffish is in trouble.
Their numbers have declined drastically over the past 30 years.
Especially the spotted wolffish and the northern, known as jelly cat to many fishermen. They are both listed as threatened.
In other words if action isn't taken these fish could be on the path to extinction.
The other wolffish, the striped, seems to be in somewhat better shape. However it's being watched carefully and is listed as being of special concern.
So what can fishermen do when they show up on their hooks and in their nets?
Basically fishermen are advised to keep an eye out for them, handle them carefully, and release them as soon as possible.
We do not yet fully understand the three species of wolffish, yet, each year, more and more information is being gathered in different parts of the North Atlantic, including in Newfoundland and Labrador and in Quebec.
Dr. Scott Grant and his team from the Marine Institute of Memorial University in Newfoundland have been searching for ways to reduce wolffish mortality on the large FPI trawlers that fish the Grand Banks.
He's found that wolffish can survive out of water for a long time.
"What we're doing is that we're taking wolffish out of bottom trawls for yellowtail flounder.
These are wolffish that are hauled up off the ocean floor, placed into a processing ramp, and handled within anywhere from 15 minutes to two hours after they have come out of the water."
Can they last that long, two hours?
"Our studies have shown that, yes, even when some of the wolffish --some of the wolffish, not all of them, but when they are out of the water for up to two hours, they can survive well when put on the ocean floor for two to three days.
So it's very important to get any fish back into the water as quick as possible.
What we're looking at here is... is verifying--well, not verifying, but showing fishermen that even though they are coming up, wolffish are coming up in the ramp of a large-bottom trawler and have the potential to remain in that ramp for up to two hours, that it is still worth throwing them back at the end of that two-hour period because some of those fish will survive.
As I mentioned before, their activity levels tend to decline substantially with time, but we have had fish on the ocean floor put back in cages, they were lowered back to the ocean floor on the Grand Banks, in the same grounds where the fish were captured from, the cages were hauled back from the ocean floor after two to three days, and all these wolffish were alive and active after that period of time. And these are fish, as I mentioned before, that were out of the water from a half-hour to two hours."
Though many fishermen consider the wolffish to be a nuisance and a competitor on the fishing ground, they must do their best to protect the species and whenever possible, release them unharmed.
Wolffish are part of a delicate ocean ecosystem that we are only beginning to understand. They must be protected.
If their numbers continue to decline, commercial fisheries could be affected.
It's in the fishermen's own interest to protect the wolffish and other threatened or endangered species.
Hopefully, fishermen everywhere will do their best to make sure this interesting creature, the wolffish, will always be found in our waters.
Brought to you by the Government of Canada
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