Scallops: Wild

Giant scallop

Hotate

Farmed scallops are a more sustainable option than wild-caught scallops, however the vast majority of scallops on the market are wild caught and rank as either “Some Concerns” or “Avoid” depending on region. Because of how they feed, in some situations scallops may improve water quality, and since they do not rely on fishmeal or fish oil-based feeds, scallop farms have a low impact on marine resources. In addition, scallop farms rarely use fertilizers, antibiotics and other chemicals that could spread into surrounding waters. Of the two ways to farm scallops, off-bottom culture is preferred. Some scallop farming does have habitat impacts as well as impacts to marine resources because of dredging and the collection of wild larvae (spat). 

Dredging is the harvest method for wild scallops, which has severe habitat impacts and bycatch concerns.

Sea scallops exhibit a high intrinsic population growth rate, high individual growth rate, low age at first maturity, and high egg production. Scallops reach harvestable size between the ages 4-7 (based on shell size) and live as long as 29 years.

The stock status of scallops depends on the area. The offshore fishery has reduced its effort (in regions other than Georges Bank) in the last decade but maintained high catch levels. Despite a long fishing record, offshore sea scallop stocks in Canada are currently not considered overfished. Recruitment in the Bay of Fundy fishery is low in several areas while in Quebec stocks are considered low (with the exception of the North Shore area where catches have remained constant).

In all areas, catches have declined from when the fisheries first began. The Department of Fisheries and Oceans (DFO) stock assessment reports cover one region at a time, and stocks and data are not always reported in the same manner. Consequently, knowledge of the population abundance of Canadian wild scallop stocks is fragmentary.

Overall, stock status is considered to be in moderate condition due to many unknown factors.

Scallop dredges may catch many species in addition to their targeted species. However, there is either limited or no long term or systematic analysis of this bycatch from the
Canadian scallop fishery. Some of these bycatch species are listed as a conservation concern by COSEWIC, such as winter skate and Atlantic cod (endangered in some regions).

However, when data is available, these bycatch events are sporadic, flat or in decline, and it has recently been shown that winter skate have a high post-release survival rate. In addition, there are several measures in place to help reduce bycatch such as gear modifications, area/time closures to protect spawning stocks and bycatch restrictions.

However, these measures have not been in place long enough to know how effective they are. Historically, there has been a lack of research on the quantity of bycatch and its impact on populations, but new reports on bycatch trends have been made available recently. Bycatch from the Canadian scallop fishery is rated as a moderate conservation concern.

Scallop dredging impacts habitats by changing their physical and biological structure. Dredging is a fishing method that causes great damage, and the scallop dredge fishery occurs in moderately resilient habitat over a moderate spatial scale. Ecosystem effects have been detected; however, there are few studies with adequate controls comparing impacted areas to those that have never been fished. Dredging can also impact populations of scallop and result in indirect mortality of the target species by altering the size structures and resilience of the species.

As a result, the effects of fishing practices on habitats and ecosystems are considered severe and are a high conservation concern.

The Department of Fisheries and Oceans (DFO) provides routine stock assessments with both fishery-dependent and fishery independent data. Management has implemented good practices such as limited entry,gear restrictions, establishment of fishing areas and seasons, and meat counts. Catches are monitored through an industry-funded dockside monitoring program. In addition, all offshore and Maritime Region vessels are required to carry vessel monitoring systems.

Canadian management has been faulted for failing to address habitat impacts but overall has implemented the good management practices mentioned above. Measures are in place
to address bycatch of commercial and non-commercial species, but further improvement is needed. Although some habitat maps completed by the fishing industry have not been released for management purposes, some seabed mapping has occurred, leading to a decreased footprint for the dredge fishery.

However, these maps have also allowed vessels to target older brood stocks and access areas previously protected due to the potential for gear hang-ups.

Overall the management of the Canadian Atlantic Scallop fishery is a moderate conservation concern.

Are these scallops wild or farmed?

Where were they caught?

How were they farmed?

Farmed suspended culture scallops are is the most sustainable choice.

Contaminant levels do not warrant a consumption advisory.

Yes. A portion of the Eastern Canada offshore scallop fishery was certified by the MSC in March 2010.

Scallops harvested from Scallop Fishing Areas (SFA) 10, 11, 12, 25, 26, & 27 are MSC certified.