American Plaice Newfoundland and Labrador population
Scientific Name: Hippoglossoides platessoides
Taxonomy Group: Fishes
COSEWIC Range: Atlantic Ocean
COSEWIC Assessment Date and Status Change: April 2009
COSEWIC Status: Threatened
COSEWIC Status Criteria: Met criteria for Endangered, A2b, but designated Threatened, A2b, because the distribution has remained stable, and the present level of abundance appears to be such that it is unlikely that there is a 20% chance of extinction within 5 generations (80 yrs).
COSEWIC Reason for Designation: This right-eye flounder burrows in sediment to escape predators and ambush prey. It is widely distributed on both sides of the North Atlantic Ocean, from the Barents Sea to the British Isles in the east, and from northern Baffin Island to Rhode Island in the west. This population occurs from Hudson Strait to the southern limit of the Grand Bank, and westward north of the Laurentian Channel to the southwestern corner of Newfoundland. A relatively sedentary, non-schooling species, it was likely once the most abundant flatfish in the northwest Atlantic, and the fishery for it in Newfoundland waters was once the largest flatfish fishery in the world. Over a 47 year time series, (about 3 generations) abundance has declined approximately 96%. Overfishing is a major cause of the decline, but an apparent increase in natural mortality in the 1990s, when the largest part of the decline occurred, may also have contributed. The decline now appears to have ceased, but numbers remain below a precautionary threshold estimated for this stock. The directed fishery is under moratorium but some significant and poorly regulated bycatches are negatively influencing recovery. In addition, fishing gear is size selective, cropping large individuals, and reducing population reproductive potential. There is evidence that natural mortality has increased which reduces the ability of the population to withstand fishing mortality.
COSEWIC History of Status Designation: Designated Threatened in April 2009.
SARA Status: No schedule, No Status
Date of Listing (yyyy-mm-dd):
Please note that this information is provided for general information purposes only. For the most up to date and accurate list of species listed under the Species at Risk Act, please see the Justice Laws Website.
American Plaice is a flat fish with a rounded tail fin. When a young plaice hatches, it has a normal fish shape. As it develops and settles to the bottom of the ocean, one side of its body becomes flat and its left eye migrates to the right side. This flattened body allows the plaice to lie flat on the ocean floor and swim on its side. The underside of the fish is white and the upper side (which now has both eyes) is coloured reddish-brown so that the plaice can camouflage itself in the sediment. The mouth is large, and the jawbone extends below the mouth. A relatively slow-growing fish, adult plaice can grow upwards of 60 cm in length.
The Newfoundland and Labrador population of American Plaice occurs in the waters immediately south of Hudson Strait southeast to the Grand Banks (east of Newfoundland), and west to Cape Ray (southwestern tip of Newfoundland) (Northwest Atlantic Fisheries Organization Areas 2GHJ3K, 3LNO, and 3Ps3Pn). American Plaice eggs and larvae drift in the open water for the first few weeks of life. As they grow, plaice settle to the ocean floor. Both juveniles and adults prefer areas with sediment suitable for burrowing. Burrowing allows plaice to hide from predators and ambush prey, making sediment type a significant factor in habitat selection. American Plaice are typically found at depths ranging from 100 to 300 metres, and preferred water temperatures are between -0.5ºC and 2.5ºC in the Newfoundland and Labrador area.
According to the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), the primary factor thought to be responsible for the decline of American Plaice stocks is overfishing, although increased natural mortality due to unusually cold water conditions may also have played a role. COSEWIC indicates that by-catch in fisheries directing for other species is also a threat.
Provincial and Territorial Protection
PLEASE NOTE: Not all COSEWIC reports are currently available on the SARA Public Registry. Most of the reports not yet available are status reports for species assessed by COSEWIC prior to May 2002. Other COSEWIC reports not yet available may include those species assessed as Extinct, Data Deficient or Not at Risk. In the meantime, they are available on request from the COSEWIC Secretariat.
4 record(s) found.
- COSEWIC Status Reports (1 record(s) found.)
- Response Statements (1 record(s) found.)
- COSEWIC Annual Reports (1 record(s) found.)
- Consultation Documents (1 record(s) found.)
COSEWIC Status Reports
COSEWIC Annual Reports
COSEWIC Annual Report - 2009 (2009-08-28)2009 Annual Report to the The Minister of the Environment and the Canadian Endangered Species Conservation Council (CESCC) from the Committee on the Status of Endangered Wildlife in Canada.