PORTLAND – The Atlantic red crab, which lives at depths of thousands of feet 100 miles off the Maine coast, is today the subject of in-depth research for the first time in almost three decades.

At the same time, federal officials are considering whether the commercial fishing of the crabs now should be regulated.

The sudden interest in red crabs has grown out of increased fishing pressure caused by Alaskan factory ships that began fishing in East Coast waters in 1999 and 2000.

New England fishermen, alarmed by the arrival of ships searching for new areas to harvest, requested both the red crab study and the proposed management plan.

Commerce Secretary Don Evans will decide next Wednesday whether to approve the plan, which was developed by the New England Fishery Management Council.

The management plan proposes trip limits of 75,000 pounds, which would effectively discourage the Alaskan ships from entering the New England fishery. If approved July 31, the plan would take effect 30 to 60 days later.

There are only four major boats that harvest red crabs in New England. They operate 100 miles offshore, using 90-foot vessels with strings of traps that stretch for miles. The crabs live at depths of 600 to 3,000 feet or more.

An estimated 700 million pounds of the colorful crab were caught in 2000, but no one really knows how healthy the population is, or how much fishing pressure it can take.

“It’s a species that’s restricted to a relatively narrow band way offshore, on the edge of the continental slope,” said Rick Wahle, a scientist at the Bigelow Laboratory in West Boothbay Harbor. “Typically these deep-water species are slow-growing, so there’s a lot of concern about whether they can sustain the kind of hammering that the American lobster seems to be able to withstand.”

The Alaskan ships came east following the decline of their king crab fishery. The East Coast’s unregulated fishery for red crab, which has a similar taste, seemed like a natural replacement.

The Alaskan ships, which have a greater capacity for catching and processing crabs, raised the possibility of overfishing.

Concerns about the red crab’s sustainability led fishermen to approach Wahle two years ago to conduct the species’ first survey since 1974.

He designed a three-year study to measure the creatures’ abundance and provide a better understanding of their lives.

The research began in late April aboard the Hannah Boden, the fishing vessel made famous by the book “The Perfect Storm.” The boat was made available by Jon Williams, a Westport fisherman and one of the vessel’s owners.

During their trips, researchers take hundreds of pictures with a digital camera that is mounted on a sled and towed along the ocean bottom. Back on shore, an image analysis system counts the number of crabs visible.