Clams: Arctic Surf

Stimspons surf clam, Arctic surf clam, hard clam

Hokkigai

The Arctic surf clam ranges from 75-125 mm in adult sizes and is similar in appearance to the more common Atlantic surf clam. The main distinguishing feature is that most specimens of Arctic surf clam have a purple color in the foot and mantle that turns red upon cooking, similar to lobster and shrimp. These clams are are slow growing and long-lived, with a maximum recorded age of 56 years and 157 mm in shell length. Offshore populations reach reproductive maturity between 5 and 8 years and spawn in the fall. This species is found in both the Atlantic and Pacific oceans in medium to coarse sandy bottoms.

The hard shell clams, including the Artic surf clam and the ocean quahog mature between 5-8 years of age, but can live decades to centuries in their natural environment.These species are considered to have a moderate to high conservation concern in terms of resilience to fishing pressure.

There have not been publicly available stock assessments of the offshore clam species since 1996. In the offshore fishery, stock assessments are based on trawl surveys in cooperation with the fishing industry, with each area surveyed every 5 years. Fishery dependent data is also incorporated. Estimating biomass and recruitment to the fishery remains a challenge. Offshore stocks are considered of moderate concern, primarily due to lack of information and the potential for fishery impacts on the population, given the uncertainties in the standing stock biomass.

Bycatch of the offshore dredge fishery in Nova Scotia includes over 200 other species of animals. The propeller clam is a major bycatch species, and is not targeted specifically but there are markets for this species. Sand dollars and groundfish are also caught. In Newfoundland, on the Southeast shoals, there are unique populations of mollusks that may be impacted by the dredge fishery. Because of the number of species impacted, bycatch in the dredge fishery is considered of high conservation concern.

Hydraulic clam dredging is one of the most destructive types of fishing as the sea floor is liquidized to extract the target species. Experiments on the Scotian Shelf have found little recovery from fishing after three years. While clam dredging only takes place in areas where clams are abundant, and the spatial extent of this area is small, these areas are heavily impacted. As the clam fishery has been in operation for the past 15 years, and only one study has been conducted on the ecosystem impacts, it is unclear how long the fishery and the seafloor environment take to recover. Habitat effects of this fishery are severe.

Currently, 4 vessels fish the offshore clam populations in Atlantic Canada. Management is industry dependent as industry funds much of the science and monitoring. There is good knowledge of the extent of the fishery. Efforts to mitigate impacts of the fishery on bycatch and particularly on the marine ecosystem are lacking. Relatively consistent catches have been maintained over the last decade, however the fishery is also exploiting new areas each year. Given the uncertainties in the ability of the stock to withstand fishing pressure, management is considered to be moderate.

Are these wild or farmed clams?

Farmed clams represent a “Best Choice”

Adults and children can safely eat more than 4 meals per month + Low contaminant levels

No.