Seafood Results

Summary

Commercial oyster landings were at an all-time high in the late 1800’s and early 1900’s, but the population decreased sharply in the mid 1900’s due to several factors including disease, overharvesting, and pollution. Currently, about two thirds of all oysters are wild-caught, and most of them originate from the Gulf of Mexico.

The population in the Gulf of Mexico is moderately abundant. The eastern oysters have a low vulnerability to fishing pressure because they are fast to mature. However, population abundance can vary greatly and is susceptible to declines due to pollution, loss of habitat, weather events, predation, and disease.

Each state manages the eastern oyster individually. The stocks are generally well managed, as all states have established size limits, seasons, gear restrictions, and area-specific closures. Both fishery-independent and fishery-dependent research is conducted. Of some concern is the fact that none of the states have a total allowable catch established, except for Florida.

The eastern oyster is harvested using tongs or dredges that are dragged over sandy or silty substrate which is covered in 100% oyster shells, both living and dead. This means that only oysters are harvested. Occasionally, a predator of the oyster called the oyster drill, found attached to the oyster, is also caught, but this amount of bycatch is minimal.

Although dredges are known to cause habitat damage to hard bottom substrate, eastern oysters are harvested in sandy and mud bottom substrate, where damage is minimal. There are conflicting opinions on whether hand tongs cause damage to oyster reefs, but all states have a habitat replenishment program in place that serve to minimize any possible negative effects of hand tonging.

Learn more about harvest methods

• Dredge
• Tong

Summary

The eastern oyster is found in the Canadian Southern Gulf of St Lawrence in New Brunswick, Prince Edward Island and Nova Scotia. Although abundance is unknown, management regulates the fishery via minimum size limits and fishing seasons. Eastern oysters are harvested by hand using tongs and rakes. This method of harvest is selective and causes minimal bycatch. Minimal habitat damage is caused. Between 2012-2014, landings have not surpassed 2,000 mt. Aquaculture produces about 2-3 times the amount of wild eastern oyster product on the market, with Prince Edward Island being the major producer.

Learn more about harvest methods

• Hand rake
• Tong

Summary

Oyster production has increased sharply since the 1990’s, and oysters represent the greatest proportion of molluscs cultured. Oysters are cultured either in suspension (off-bottom culture) where they are grown on rafts, racks, or stakes, or can be grown on the sea floor (on-bottom culture) where they are sown in beds and harvested after grow-out.

As oysters are filter feeders, no external feed is used as the individuals derive nutrition directly from the surrounding ocean. Broodstock is sourced from natural settlement, or from hatcheries. Domesticated sources of broodstock may be geneticially different from wild populations, but the vast majority of oysters are sourced from natural settlement. Management measures include export regulations, health codes, farm siting etc. Best Management Practices help to reduce risk of disease and pathogens.

Oysters are broadcast spawners, therefore escape of larvae to the open ocean is possible. There is concern over the impact of escapes if the cultured oysters are raised in non-native environments. However, in some areas, oysters are fully established, having been introduced over 10 years ago. Risk of disease and parasite transmission to wild populations is low due to biosecurity measures and production practices.

There is the possibility of changes to the sediment directly below farms due to biodeposition, but these impacts are minimal and do not extend beyond the farm site. Oyster farming has been observed to positively affect the ecosystem by removing excess nutrients from water.

Learn more about harvest methods

• Off-bottom culture
• On-bottom culture

Summary

An average of 315 mt of oysters are exported from the US each year, mostly to Canada, Hong Kong and Taipei; however, available data does not specify the species of oyster or whether they were captured wild or farmed. Eastern oysters are caught in several East coast US states. Stocks are healthy in Delaware, but historically overfished in Maryland, Rhode Island, North Carolina, Virginia and South Carolina. Both fishing methods (towed dredges and hand implements) are highly selective and bycatch is negligible.

Management strategies are different in each state, but all employ size limit regulations, seasonal and area closures and gear restrictions to promote oyster abundance. There is strong enforcement of regulations and stakeholder involvement is high. As the oyster is a keystone species for a healthy estuarine environment, all the states have implemented reef restoration projects, which are too recent to measure any success, but have shown signs of improving conditions.

Learn more about harvest methods

• Dredge
• Hand harvest

Summary

In 2012 Seafood Watch completed a comprehensive study of different eco-certification programs to determine if any would be equivalent to their sustainability standards. As a result of this study this aquaculture eco-certification were determined to be equivalent to an Ocean Wise recommendation. Learn more about our recommendation policy here.

Learn more about harvest methods

• Various

Summary

In 2012 Seafood Watch completed a comprehensive study of different eco-certification programs to determine if any would be equivalent to their sustainability standards. As a result of this study this aquaculture eco-certification were determined to be equivalent to an Ocean Wise recommendation. Learn more about our recommendation policy here.

Learn more about harvest methods

• Various

Summary

In 2012 Seafood Watch completed a comprehensive study of different eco-certification programs to determine if any would be equivalent to their sustainability standards. As a result of this study this aquaculture eco-certification were determined to be equivalent to an Ocean Wise recommendation. Learn more about our recommendation policy here.

Learn more about harvest methods

• Various

Summary

Ocean Wise recommends some Marine Stewardship Council (MSC) certified fisheries, but not all. Learn more about how the MSC certification was bench-marked to Ocean Wise.

Learn more about harvest methods

• Dredge

Summary

Ocean Wise recommends some Marine Stewardship Council (MSC) certified fisheries, but not all. Learn more about how the MSC certification was bench-marked to Ocean Wise.

Learn more about harvest methods

• Hand harvest

Summary

Ocean Wise recommends some Marine Stewardship Council (MSC) certified fisheries, but not all. Learn more about how the MSC certification was bench-marked to Ocean Wise.

Learn more about harvest methods

• Dredge

Summary

Ocean Wise recommends some Marine Stewardship Council (MSC) certified fisheries, but not all. Learn more about how the MSC certification was bench-marked to Ocean Wise.

Learn more about harvest methods

• Dredge

Summary

An average of 315 mt of oysters are exported from the US each year, mostly to Canada, Hong Kong and Taipei; however, available data does not specify the species of oyster or whether they were captured wild or farmed. The eastern oyster fishery in New York uses hand implements and available data indicates that stocks are overfished. Some controls are in place to limit fishery impacts, including recreational harvest limits a size limit, but there is no limit for commercial fishing or seasonal closures. No information has been reported on the abundance of stocks since 2005. Reef restoration projects are in place and there are no issues with bycatch.

Learn more about harvest methods

• Hand harvest