No one would call a snow crab pretty. The flat, 10-legged crustacean, whose carapace can grow to about 6 inches in size, looks like a creature concocted by a Hollywood horror movie director. But the homely deepwater crab, once landed, has translated into a lot of money for fishermen around the Gulf of St. Lawrence in Canada. The snow crab fishery, however, has been tagged as a likely culprit in the 2017 deaths of endangered North Atlantic right whales in Canadian waters.
The snow crab fishery started slowly in the Gulf of St. Lawrence. According to an article by Karen Pinchin published by the CBC in 2018, snow crab was first landed as bycatch by ocean draggers in the 1960s. By 1968, just a few dozen fishermen deliberately set for snow crab in the area around the Gaspé peninsula and west of Cape Breton.
The Canadian Department of Fisheries and Oceans (DFO) began regulating the fishery during the 1970s, instituting trap limits and a minimum mesh size for nets and restricting landings to only male crabs. In 1982, fishermen landed 35,000 tons of snow crab from the Gulf of St. Lawrence region. But, as has happened with so many commercial marine species, overfishing took its toll on the stock. By 1989 landings had dropped to 8,000 tons.
But the Gulf of St. Lawrence population slowly recovered, in part due to additional management measures by DFO such as individual boat quotas and dockside monitoring. The quota for the Gulf, which is divided into several smaller management areas, was increased. In 2016, the official quota was 20,000 tons. Approximately $129 million worth of snow crab was landed in Nova Scotia, Prince Edward Island, and New Brunswick that year, primarily from Area 12 in the Gulf of St. Lawrence. Snow crab exports in 2016 hit $280 million, with 83% going to the United States and 12% to Japan.
In 2017 DFO decided to increase the snow crab quota, more than doubling it to 43,475 tons. Fishermen met and ran slightly over that quota, bringing in 43,656 tons. The2017 value topped $221 million. But, concerned by an apparent drop in the snow crab biomass, DFO reduced the quota for 2018 by 43%, down to 22,000 tons. Landings for 2018 have not yet been published but anecdotal information indicates a drop in the harvest due in part to a delay in the season due to ice and and to fishing area closures instituted because of the presence of right whales. The London-based Marine Stewardship Council also suspended its certification of the fishery as sustainable in 2018 based on the previous year’s whale deaths.
Snow crab quota corresponds closely to right whale entanglement, with one entanglement in snow crab gear observed in each year in 2014 and 2015, three in 2016, seven in 2017 and one in 2018. The snow crab entanglements from 2016 to 2018 were particularly hard on the right whale population, resulting in 11 serious injuries and mortalities.
In addition to the reduction in quota in 2018, DFO also instituted new right whale protection measures in the Gulf of St. Lawrence snow crab fishery during the 2018. These included a closure in a known feeding ground, dynamic closures when whales where sighted around the foraging area, gear modifications to limit the amount of rope in the surface system and ban floating line on the surface, and gear marking requirements. The snow crab fishery is also subject to several strict reporting requirements.
DFO began an assessment of the snow crab population status in the Gulf of St. Lawrence area and off Newfoundland and Labrador in 2017. The report, issued in October 2018, surprised many. The biomass of snow crab off Newfoundland was the lowest in 25 years. Furthermore, the steady harvesting of larger male crabs has had an impact on succeeding generations. Scientists found that 80% of the current crab stock were below commercial size. Apparently when there are fewer large males in the population, the smaller male crabs terminally molt earlier, which means that they stop growing at a smaller size.
The annual quota for snow crab in the Gulf of St. Lawrence was reduced in 2018. That and the new federal regulations may have had the effect of protecting the migrating right whales as no new deaths were reported that year. DFO is currently finalizing measures to protect right whales in 2019; the snow crab quota for 2019 in the Gulf of St. Lawrence has not yet been released.