1 Winter Skate (Leucoraja ocellata) (Southern Gulf of St. Lawrence population, Eastern Scotian Shelf population and Georges Bank–Western Scotian Shelf–Bay of Fundy population)
The Minister of the Environment has recommended, on the advice of the Minister of Fisheries and Oceans, that the Winter Skate (Southern Gulf of St. Lawrence population, Eastern Scotian Shelf population and Georges Bank–Western Scotian Shelf–Bay of Fundy population) not be added to the List of Wildlife Species at Risk.
Skate are a fish species found around the world in water depths from shallow to deep. They are easily recognized by their flattened diamond shape, the result of greatly enlarged pectoral fins. They also have a long tail with two small dorsal fins near the tip. The upper surface is usually light to dark brown and the underside white to greyish.
Winter Skate are distinguished from other skates by their rounded snout and eye spots on the upper side near the corner of the pectoral fins. However, these eye spots are not always present. In the absence of eye spots, a closer inspection of a variety of other characteristics must be carried out to correctly distinguish this species, particularly from Little Skate (Leucoraja erinacea) whose range overlaps that of Winter Skate. The lower surface of Winter Skate is usually whitish, often with irregular brownish blotches near the rear and tail.
Winter Skate are found only in the northwest Atlantic, where approximately 50 percent of their range occurs in Canadian waters. They occur from the Gulf of St. Lawrence and southern Newfoundland in Canada to Cape Hatteras, North Carolina in the United States. However, they are most abundant on Georges Bank, the Scotian Shelf and the Southern Gulf of St. Lawrence in Canada and off southern New England in the United States.
The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) states that available evidence supports dividing the Canadian Winter Skate into four populations. The following three populations have been considered for addition to the List: the Southern Gulf of St. Lawrence Eastern Scotian Shelf, and Georges Bank–Western Scotian Shelf–Bay of Fundy populations. The fourth population, the Northern Gulf–Newfoundland population, was assessed as Data Deficient and therefore, not considered for addition to the List.
The prohibitions under section 32 of the Species at Risk Act (“the Act”), which come into effect after listing a species as threatened or endangered, require that any activity that would result in killing, harming, harassing, capturing or taking the listed species be stopped immediately. This would include fishing activity, if the Winter Skate is caught as bycatch while listed as threatened or endangered, as is the case for the Southern Gulf of St. Lawrence and Eastern Scotian Shelf populations, which have been assessed as endangered species and threatened species respectively. The negative socio-economic impacts of listing these populations would be significant and the population trajectory of the species is unlikely to be reversed as a result of the listing. The closure of commercial fisheries in Northwest Atlantic Fisheries Organization areas 4T and 4VW, which would be necessary as a result of listing these populations, would result in millions of dollars in lost revenue annually, as well as significant direct and indirect job losses.
There is a lack of support from New Brunswick, Nova Scotia, Prince Edward Island, Quebec and industry stakeholders for the listing of these three populations of Winter Skate. Some Aboriginal communities have also expressed reservations about listing.
There have been significant declines in the Southern Gulf of St. Lawrence and the Eastern Scotian Shelf populations of Winter Skate, while the abundance of mature Winter Skate is steady in the Georges Bank–Western Scotian Shelf–Bay of Fundy population and the geographic range of the population has neither increased nor decreased since the last abundance estimates were completed. While fishing is believed to be the main human activity directly affecting the Winter Skate populations, it is estimated to contribute very little to the current elevated mortality of mature Winter Skate. The COSEWIC status report notes that the dominant impediment to this species’ recovery potential is the high rate of natural mortality within the remaining adult population. The significant declines are understood to be related to the life-cycle characteristics of the Winter Skate, which include a delayed age at maturity, an extended intergenerational time and low fecundity. These factors, when coupled with high rates of natural mortality, increase the species’ vulnerability to exploitation and poor rate of recovery and lead to an increased risk of extinction. Adding these populations to the List would not help address the high rate of natural mortality that is the main concern regarding the species’ recovery, producing very little benefit to the species while incurring significant economic costs.
The primary source of human induced mortality, bycatch, can be addressed through the Fisheries Act, which provides legally enforceable protection measures. Targeted conservation measures will be included in the groundfish Integrated Fisheries Management Plans and implemented as conditions of fishing licenses issued for groundfish. The measures would reduce human induced mortality and would include, but would not be limited to, continued closure of the commercial skate fishery, mandatory discarding of all Winter Skate caught as bycatch, including live release of Winter Skate, wherever possible, and monitoring to determine discard rates. For the primary human induced threat, bycatch, existing legislation is available to establish the regulatory and management framework required to promote recovery of the species. These measures would be similar to measures contained in a management plan compliant with the Act.
2 Chinook Salmon (Oncorhynchus tshawytscha) (Okanagan Population)
The Minister of the Environment has recommended, on the advice of the Minister of Fisheries and Oceans, that Chinook Salmon (Okanagan population) not be added to the List.
The Chinook Salmon (Oncorhynchus tshawytscha) is one of six species of the Pacific salmon (genus Oncorhynchus) native to North America. Chinook Salmon are born in fresh water and grow in streams, lakes, estuaries or the ocean. Sexually mature or maturing fish migrate to their natal stream to spawn, in a broad range of stream flows, water depths, and substrate sizes, but preferentially in areas with intra-gravel water flow, after which the adults die. In the ocean, Chinook Salmon may remain in coastal areas or complete extensive offshore migrations.
In Canada, the Okanagan population of Chinook Salmon is limited to the Okanagan River which is a tributary of the Columbia River. While Okanagan Chinook Salmon are geographically, reproductively and genetically distinct from all other Canadian Chinook Salmon populations, studies have confirmed that a small proportion of the fish entering Canada were released from hatcheries in the United States. Perhaps as a consequence, Okanagan Chinook Salmon are genetically similar to Upper Columbia Summer Chinook. A recent study indicates that Okanagan Chinook Salmon are anadromous, meaning that they migrate to and from the Pacific Ocean through the Columbia River. Studies indicate that American dams on the Columbia River represent the greatest threat to the survival of Upper Columbia River Chinook Salmon.
Anadromous Okanagan Chinook Salmon enter the Okanagan River in June and July and likely remain there until spawning in October. Peak spawning generally occurs in the third week of October, when water temperatures are between approximately 10°C and 14°C. It is unknown whether spawning also occurs in early July when water temperatures are also favourable. Eggs incubate through the winter and fry emerge between January and May.
Adding Okanagan Chinook Salmon to the List would immediately activate the prohibitions contained in section 32 of the Act. Since individuals of this population cannot easily be distinguished from other co-mingling populations of Chinook Salmon, implementing the prohibitions would require the closure of all commercial fisheries in which the Okanagan population could potentially be intercepted. Consequently, commercial Chinook Salmon troll fisheries on the north and west coasts of Vancouver Island would have to be closed. The closure of these Chinook Salmon fisheries would result in the loss of approximately $19 million per year to the B.C. economy: $7.7 million per year in lost wages for people working in commercial fishing, $4.2 million per year in lost profits to the commercial fishing industry and $7.3 million per year lost in commercial fishing licence values. The Recovery Potential Assessment indicates that this reduction in catch would, by itself, not provide for the recovery of Okanagan Chinook Salmon.
The Recovery Potential Assessment for Okanagan Chinook Salmon determined that recovery of this population is highly improbable without large scale augmentation of hatchery-raised salmon. The most promising option for survival of this population is the Upper Columbia Summer Chinook Salmon hatchery which has been proposed by the Confederate Tribes of the Colville Reserve in Washington State. The augmentation of production that this hatchery would generate would increase straying of Upper Columbia Summer Chinook Salmon into the Canadian portion of the Okanagan River and could eventually result in a viable, hybrid wild Okanagan Chinook Salmon population.
Fisheries management actions to improve survival of this population have been put in place. Amendments to the Pacific Salmon Treaty in 2009 reduced catch limits on Upper Columbia Chinook Salmon by 30% on the west coast of Vancouver Island and by 15% in southeast Alaska. The federal government will continue to manage the Okanagan Chinook Salmon under the Fisheries Act.
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