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Halichoerus grypus Fabricius, 1791 ♀♂

Halichoerus grypus-FM.JPG <b><i>Halichoerus grypus</b></i> Fabricius, 1791 ♂||<img src=./_datas/t/6/y/t6ynvw9sux/i/uploads/t/6/y/t6ynvw9sux//2016/08/15/20160815102147-9ba393dd-th.jpg>Thumbnails<b><i>Halichoerus grypus</b></i> Fabricius, 1791 ♀||<img src=./_datas/t/6/y/t6ynvw9sux/i/uploads/t/6/y/t6ynvw9sux//2016/08/15/20160815102145-f90ad95a-th.jpg><b><i>Halichoerus grypus</b></i> Fabricius, 1791 ♂||<img src=./_datas/t/6/y/t6ynvw9sux/i/uploads/t/6/y/t6ynvw9sux//2016/08/15/20160815102147-9ba393dd-th.jpg>Thumbnails<b><i>Halichoerus grypus</b></i> Fabricius, 1791 ♀||<img src=./_datas/t/6/y/t6ynvw9sux/i/uploads/t/6/y/t6ynvw9sux//2016/08/15/20160815102145-f90ad95a-th.jpg><b><i>Halichoerus grypus</b></i> Fabricius, 1791 ♂||<img src=./_datas/t/6/y/t6ynvw9sux/i/uploads/t/6/y/t6ynvw9sux//2016/08/15/20160815102147-9ba393dd-th.jpg>Thumbnails<b><i>Halichoerus grypus</b></i> Fabricius, 1791 ♀||<img src=./_datas/t/6/y/t6ynvw9sux/i/uploads/t/6/y/t6ynvw9sux//2016/08/15/20160815102145-f90ad95a-th.jpg><b><i>Halichoerus grypus</b></i> Fabricius, 1791 ♂||<img src=./_datas/t/6/y/t6ynvw9sux/i/uploads/t/6/y/t6ynvw9sux//2016/08/15/20160815102147-9ba393dd-th.jpg>Thumbnails<b><i>Halichoerus grypus</b></i> Fabricius, 1791 ♀||<img src=./_datas/t/6/y/t6ynvw9sux/i/uploads/t/6/y/t6ynvw9sux//2016/08/15/20160815102145-f90ad95a-th.jpg>

Halichoerus grypus Fabricius, 1791 ♀♂
Common names: Grey seal, Atlantic seal, Horsehead seal [En], Phoque gris, Tête de cheval [Fr], Grijze zeehond [Nl], Kegelrobbe [De], Foca grigia [It], Foca gris [Es], Boz fok [Tu]

Berck-sur-Mer, PAS-DE-CALAIS ● France

Description: It is a large seal, with bulls in the eastern Atlantic populations reaching 2.5–3.3 m long and weighing 170–310 kg; the cows are much smaller, typically 1.6–2.0 m long and 100–190 kg in weight. Individuals from the western Atlantic are often much larger, males reaching 400 kg and females weighing up to 250 kg.
It is distinguished from the harbor seal by its straight head profile, nostrils set well apart, and fewer spots on its body. Gray seals lack external ear flaps and characteristically have large snouts. Bull Greys have larger noses and a less curved profile than common seal bulls. Males are generally darker than females, with lighter patches and often scarring around the neck. Females are silver grey to brown with dark patches.
There are two recognized subspecies:
H. g. grypus – North Atlantic;
H. g. macrorhynchus – Baltic Sea.
However, Boskovic et al. (1996) found large differences in mtDNA between the three breeding areas, with the Baltic and east Atlantic populations much closer to one another than they were to the west Atlantic population.
The IUCN Pinniped Specialist Group prefers the common names Northwest Atlantic Grey Seal and Northeast Atlantic Grey Seal, and has assessed those subspecies separately.

Biology: The grey seal feeds on a wide variety of fish, mostly benthic or demersal species, taken at depths down to 70 m (230 ft) or more. Sand eels (Ammodytes spp) are important in its diet in many localities. Cod and other gadids, flatfish, herring and skates are also important locally. However, it is clear that the grey seal will eat whatever is available, including octopus and lobsters. The average daily food requirement is estimated to be 5 kg, though the seal does not feed every day and it fasts during the breeding season.
The pups are born at around the mass of 14 kg, in autumn (September to November) in the eastern Atlantic and in winter (January to February) in the west, with a dense, soft silky white fur; at first small, they rapidly fatten up on their mothers' extremely fat-rich milk. The milk can consist of up to 60% fat. Within a month or so they shed the pup fur, grow dense waterproof adult fur, and leave for the sea to learn to fish for themselves.

Habitat: During the winter months grey seals can be seen hauled out on rocks, islands, and shoals not far from shore, occasionally coming ashore to rest. In the spring recently weaned pups and yearlings occasionally strand on beaches after becoming separated from their group.

Distribution: Grey Seals have a cold temperate to sub-Arctic distribution in North Atlantic waters over the continental shelf.
The grey seal breeds in several colonies on and around the coasts in the United Kingdom, Ireland and Northern France.
It is typically found in large numbers in the coastal waters of Canada and south to about New Jersey in the United States.
An isolated population exists in the Baltic Sea, forming the H. g. macrorhynchus subspecies.

Threats & Protection: Over-harvesting in the Baltic in the early 20th century led to a large decline; this population once numbered somewhere between 80,000 and 100,000, but was reduced to about 20,000 in the 1940s. A further decline to 1,500-2,000 seals was caused by high loads of PCB.
Today, the Grey Seal has the same geographic distribution as in the late 19th century with areas of its range having been recolonized over the past 30-40 years. Their abundance has increased in all regions in the past several decades. Total abundance globally is more than 600,000.In the UK seals are protected under the Conservation of Seals Act 1970, however it does not apply to Northern Ireland. In the UK there have also been calls for a cull from some fishermen, claiming that stocks have declined due to the seals.
The population in the Baltic Sea has increased about 8% per year between 1990 and the mid-2000s with the numbers becoming stagnant since 2005. As of 2011 hunting grey seals is legal in Sweden, Finland and Denmark with 50% of the quota being used. Other anthropogenic causes of death include drowning in fishing gear.
Grey Seals are exposed to agricultural and industrial pollutants through the food chain in their coastal ranges.
After near extirpation from hunting grey seals for oil, meat and skins in the United States, sightings began to increase in the late 1980s. One year after Congress passed the 1972 Marine Mammal Protection Act preventing the harming or harassing of seals, a survey of the entire Maine coast found only 30 grey seals. At first grey seal populations increased slowly then rebounded from islands off Maine. According to a genetics study, the United States population has formed as a result of recolonization by Canadian seals. A count of 15,756 gray seals in southeastern Massachusetts coastal waters was made in 2011 by the National Marine Fisheries Service. Also grey seals are seen increasingly in New York and New Jersey waters, and it's expected that they will establish colonies further south.

References:
Wikipedia, Grey seal
Bowen D., 2016. Halichoerus grypus, The IUCN Red List of Threatened Species.





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