10 MARINE MAMMALS AND SEA TURTLES - Hebron Project

Hebron Project Comprehensive Study Report
Marine Mammals and Sea Turtles
an estimated 99,340 individuals in the Northwest Atlantic (Waring et al.
2009). Hammill and Stenson (2000) estimated a total of approximately 5,120
harbour seals in Newfoundland and Labrador in 1996, and further information
suggests there may be at least 1,000 animals in coastal Newfoundland (Sjare
et al. 2005a; COSEWIC 2007a).
Harbour seals are found in coastal areas, rarely more than 20 km from shore,
and often enter bays, estuaries, and inlets where they sometimes also follow
anadromous salmonids up coastal rivers (Baird 2001). They periodically haul
out of the water at coastal sites, usually rocky outcroppings and intertidal
ledges. Primary prey in Newfoundland include winter flounder, cod, and
sculpins (Sjare et al. 2005a). In Nova Scotia, harbour seals pup in the spring,
primarily in May and June, and pups are nursed for approximately 24 days
(Bowen et al. 2001). No studies are available to describe pupping patterns in
Newfoundland, but similar patterns are expected. Mating also tends to occur
during pupping season. Moulting occurs from mid-summer to early fall, and
harbour seals haul out more frequently than at other times of the year.
Harbour seals are primarily considered a coastal species with limited
dispersal from preferred haul out sites, but pups and juveniles have shown
movements up to hundreds of kilometres over the continental shelf from haul
out sites (Small et al. 2005). Harbour seals tagged in the St. Lawrence
estuary were shown to migrate an average of 266 km to wintering locations
exhibiting lower ice densities, but remained closer to shore (within 11 km) and
in shallow areas, traveling only short distances (15 to 45 km), during ice-free
conditions (Lesage et al. 2004).
Harbour seals are considered year-round residents of coastal Newfoundland
(Sjare et al. 2005a). Relative to other seal species in Newfoundland waters,
spatial and temporal distribution and abundance is poorly known (Hammill
and Stenson 2000). None have been sighted during summer and fall
observations on the northeastern Grand Banks, in the Jeanne d‘Arc Basin or
Orphan Basin (Moulton et al. 2005, 2006b; Lang et al. 2006; Abgrall et al.
2008a, 2008b; Lang and Moulton 2008). The Offshore Study Area is within
the maximum range reported for habour seals; however, harbour seals are
unlikely to occur there based on their preference for coastal waters.
Sjare et al. (2005a) indicate that harbour seals do not regularly occur in
Trinity Bay. Based on the absence of reports and sighting records within
Trinity Bay, harbour seals are not expected to commonly occur in the
Nearshore Study Area.
Harp Seal
The harp seal is found throughout the North Atlantic and Arctic Ocean, from
the Gulf of St. Lawrence to Russia (Jefferson et al. 2008). Harp seals are the
most abundant seal in the Northwest Atlantic, with an estimated population
size of 5.9 million in 2007 (DFO 2007b). The majority of these seals
aggregate off the east coast of Newfoundland and Labrador to pup and
breed, with the remainder of the animals whelping in the Gulf of St. Lawrence
(Lavigne and Kovacs 1988).
10-26 June 2010