Walruses can show up on Irish shores
WE LAY in the soft grass on the cliff top in pleasant autumn sunshine watching through binoculars the seals on the beaches below. Nursing mothers tended their new-born young in secluded coves safe from predators.
We have two resident species of seal in Ireland: the Grey Seal and the Common Seal. The latter is also known as the Eastern Atlantic Harbour Seal. Other species turn up on rare occasions either as vagrants or very rare visitors. The most common rare visitor in Irish water is the Walrus; its wanders down from its Arctic home range and occasionally makes an appearance along our western seaboard.
The seals we were looking at last week were Grey Seals. While adult males are called bulls and adult females are called cows the young are called pups rather than calves. We recorded 14 pups at six pupping sites on the eastern and southern shores of the island. In addition to the pups, seven adults were hauled out on beaches together with more than twenty adults bobbing about in the inshore waters just offshore.
Grey Seals are seasonal breeders and females give birth to just one pup. The peak pupping season extends from mid-September to mid-November. Pups are born on land after a very short labour. The newborn is thin-looking, baggy-skinned and bears a yellowish-white coat of long fur. Its umbilical cord shrivels and dries by its third day.
Cartons of low-fat cow's milk on supermarket shelves state that the milk contains 1% fat. Seal milk contains an amazing 60% fat so the skinny new-born very soon become girdled with rolls of fat like the tyres that make up the Michelin Man. Pups do not normally enter the sea; they stay on land and their time is spent feeding and sleeping. Their mothers keep watch from shallow inshore waters coming ashore every six hours or so to suckle their offspring.
After slightly less than three weeks the pup is weaned. It has fully moulted its white birth coat and grows a short fawn or grey spotty sea coat. Pup weaned, the mother comes into season. She abandons her offspring and her attention turns to the waiting bulls eager to mate.
The abandoned three-week old pup starts to lose weight and takes to the water where hunger drives it to get the hang of catching food for itself. With no family structure to support it, starvation and death are the stark alternatives to learning to fend for itself.