A glut of lobsters in Atlantic Canada that's driving down prices for fishermen has scientists with Fisheries and Oceans Canada stumped.
They say they don't know why there are so many lobsters in the region, but they believe the stocks will remain high.
Lobster populations are healthy, said Marc Lanteigne, the manager for aquatic resources for the gulf region.
"The increase is about three to four fold over the last 30, 40 years," he said.
Catches have also jumped to about 20,000 tonnes in the past few years, up from 8,000 tonnes in 1975, said Lanteigne.
"The only thing that we know is that it's a global factor for the entire range of lobster from Cape Cod to Labrador," he said.
There are several theories ranging from climate change, to tougher regulations and changing wind patterns, but there's no evidence to back up any of them, said Lanteigne.
"We cannot put our finger on a single element that would explain the sudden increase," he said.
Meanwhile, the glut is hurting fishermen in the region, with prices hovering at about $3 per pound, down from $4.50 per pound in 2009, according to the Lobster Council of Canada.
A Senate committee studying the state of the fishery in Atlantic Canada and Quebec is expected to make recommendations in the spring.
The lobster council is also working to expand demand in other markets, such as Asia.
This past summer, a glut of lobster from Maine flooded the New Brunswick market, driving prices down.
Lobster fishermen held several protests across the province, blocking processing plants.
They complained plant owners were paying rock-bottom prices of about $2 per pound for the Maine lobster, which would leave no market for local catches once the season opened on the Northumberland Strait.
Fishermen accepted a deal that would see processors pay $3 a pound for canners and $3.50 for market lobster.