Harp Seal | Foca da Gronelândia - Pagophilus groenlandicus
Scientific Name: Pagophilus groenlandicus
Common Name (UK, FR, PT, ES, DE): harp seal, phoque du Groenland, foca da Gronelândia, foca de Groenlandica.
Short Species description: A true seal that lives in the colder water of the north Atlantic and Arctic Oceans. Its scientific name means “ice-lover from Greenland”.
This specie is considered the most abundant marine mammal species in the North Atlantic, and an ice dependent species that rely on thick insulation to maintain thermal homeostasis. While the adult seals use primarily blubber for insulation, the newborn seals rely on a lanugo pelt while nursing, as their blubber layer develops and their first-year pelage grows. They can grow up to 1,8m and weigh up to 136kg.
The name “harp seal” comes from the curved, black patch on their backs, which resembles a harp. Males generally have a more defined dorsal marking and a darker head, while some females never develop the marking and remain spotted. Young pups are solid white.
This is a highly migratory species with individuals following Artic sea ice as it expands and contracts throughout the year. Annual migrations can be more than 5 km roundtrip to feed and they can stay underwater for at least 16 minutes at a time. They usually prefer shallow water, but they can dive as deep as 400m.
Like other pinnipeds, harp seals are carnivores. Their diet is very diverse, eating at least 67 species of fish and 70 species of invertebrates. Young harp seals eat primarily shrimp and zooplankton.
Population status: least concern by the IUCN Status; Population trend: increasing
Habitat Use: Sub-polar to polar latitudes of the north Atlantic and Arctic oceans. Three populations in the Barents Sea, East Coast of Greenland, and Northwest Atlantic Ocean are recognized based on geographic distribution as well as morphological, genetic, and behavioural differences.
Communication and Perception: Underwater research suggests that harp seals actually listen to individual calls and respond with a specific response, rather than making random sounds. They may use also underwater calling to attract mates and to coordinate herds.
Apart from underwater calling, they use clicks, trills, and other chirp-like sounds on land, especially to attract mates or to respond to a predator getting too close to a pup.
Harp seals have acute vision and hearing, which is incredibly strong underwater, but a very poor sense of smell.
Pod Size: Harp seals can form large colonies of up to several thousand to molt and breed, and they can also feed and travel in large groups during seasonal migrations. They are social animals and can be quite vocal in groups.
Typical Behaviour: Their annual movements appear to follow the development and retreat of the ice pack, and they are often seen feeding along the ice edge throughout the year. As capital breeders, harp seals must build up energy reserves that can be used during pupping and nursing when they reduce feeding
References
Pearson, L. E., Weitzner, E. L., Burns, J. M., Hammill, M. O., & Liwanag, H. E. (2019).
From ice to ocean: changes in the thermal function of harp seal pelt with ontogeny. Journal of Comparative Physiology B, 189(3-4), 501-511.
Stenson, G. B., Buren, A. D., & Koen-Alonso, M. (2016). The impact of changing climate and abundance on reproduction in an ice-dependent species, the Northwest Atlantic harp seal, Pagophilus groenlandicus. ICES Journal of Marine Science, 73(2), 250-262.
