Monday, May 20, 2013
Larry Alade, a fisheries biologist at NOAA's Northeast Fisheries Science Center, prepares to release a monkfish after implanting a tag and small data sensor into the fish. (Credit: Pasha Ivanov, NOAA)
A small sensor, or data-collection tag (left) and conventional pink t-bar tags (right) are in place on a monkfish that's about to be released. The data collection tag will track ocean temperatures and depths and help scientists study fish movement and behavior. The pink tags alert fishermen that the fish is worth a $500 bounty if returned to scientists in one piece. (Credit: Anne Richards, NEFSC/NOAA)
PORTLAND — Monkfish used to be pretty much ignored by New England fishermen and seafood consumers.
Obscurity was one of the perks of looking more like a small sea monster than a fish dinner. ''It was considered unaesthetic It was mostly discarded,'' said Graham Sherwood, a scientist at the Gulf of Maine Research Institute in Portland.
But the monkfish has become, pound for pound, the most valuable commercial fish species on the East Coast. As a result, it's getting a lot more attention from scientists.
''It's such a newcomer to the scene that we're lacking in our scientific knowledge,'' said Jonathan Grabowski, another researcher at the institute.
Sherwood and Grabowski are part of a team that's working with federal officials and fishermen to study the monkfish's behavior and biology and help managers make sure the species' commercial appeal doesn't jeopardize its population.
The two-year-old study is now going high-tech, with researchers implanting small electronic sensors into monkfish so they can monitor their environment for as long as five years.
Monkfish, also called goosefish or anglerfish, are flat bottom dwellers with oversized heads and enormous mouths with protruding lower jaws and rows of long, sharp, needle-like teeth.
Not built for speed, the monkfish captures prey by blending into the ocean floor and using a spine on its back to dangle a small fleshy tab over its head. Any fish that gets too close to the built-in lure is quickly swallowed up.
''It opens its mouth so quickly it creates a vacuum and sucks in whatever is outside,'' said Grabowski. The gaping mouth allows it to eat fish nearly as large as itself.
''We pulled a 68-centimeter cod out of a 72-centimeter monkfish,'' said Sherwood.
Monkfish started attracting attention in the seafood market in the late 1980s, and gradually developed a lucrative following.
The while tail flesh is similar in texture to lobster meat. It has become popular in high-end restaurants and specialty fish markets in the United States and Asia.
''Monk tails'' now sell for about $3.40 per pound wholesale on the Portland Fish Exchange, and retail for $7.99 or more in fish markets. Fishermen typically sell their cod and haddock at the exchange for about $1 per pound.
Monkfish livers are a popular dish in Asia and can bring fishermen as much as $10 to $15 per pound in a good market.
''The market value is pretty strong on these critters,'' said Bert Jongerden, general manager of the Portland Fish Exchange. ''There is always a strong demand for it overseas.''
Monkfish caught on at a good time, helping to keep the city-owned exchange and some Maine fishing boats in business as supplies of more traditional commercial fish declined.
''It's the most stable thing, price-wise,'' said Glen Libby, a fisherman in Port Clyde. ''People are starting to wake up to it. There's more demand for it than there was even 10 years ago.''
Monkfish, which range from Maine to North Carolina, have been regulated by federal and regional agencies since 1999. Despite the lack of understanding of the fish, the population was split into northern and southern management zones, each of which has its own complex set of conservation rules.
''The big overarching question has been: Are these two stocks mixing, and to what extent are they mixing?'' Sherwood said.
It could be, for instance, that most of the spawning occurs in one of the management zones, or that fish of certain ages spend more time in one or the other.
Such patterns, as well as inshore and offshore migrations, could affect future management decisions and future catches.
The research also could help scientists answer more basic questions, such as how fast the fish grow, how long they live and how far they travel.
Most of the funding for the studies comes from the fishing industry through a research fee. The National Oceanic and Atmospheric Administration also contributes funding. Fishermen are paid to help researchers catch, tag and release the fish.
Scientists have tagged nearly 3,000 monkfish since 2007. Some have been caught and reported by fishermen in the same areas where they were tagged, the researchers said, while one was caught off North Carolina about two years after being tagged and released off Rhode Island.
For about the past year, researchers have been implanting monkfish with sensors about the size of an AA battery cut in half.
Every five minutes, the ''data collection tags'' record the depth and temperature of the water.
If any fish are ultimately returned to the Gulf of Maine Research Institute or other labs, the researchers can use the sensors and other tests to learn about their movements, growth, foraging behavior and other things.
Researchers have implanted sensors in the backs of about 150 fish, and plan to do so in another 50.
It's an expensive undertaking. Each sensor costs about $350, and the researchers are offering fishermen $500 for any whole fish returned with the sensor intact.
''But the data contained in these tags is almost priceless,'' Sherwood said.
A pink tag on the tail means a fish carries the sensor and the $500 reward. Even with the bounty, the researchers can hope to get only a small number back.
''Five percent (10 fish) would be wonderful,'' Grabowski said. ''Even (getting back) a couple would tell us something.''
Staff Writer John Richardson can be contacted at 791-6324 or at: