Gray Seals

The gray seal feeds on fish. Its large eyes have flat corneas that enabl it to see well in murky water. Still, its sense of hearing and taste are more important when hunting, and even blind seals have no difficulty catching prey. The gray seal has no ears, but it has a sensitive internal hearing apparatus to help in tracking prey. Its nose and whiskers are sensitive enough to feel water movements made by escaping prey as the seal moves closer. Its large, highly sensitive nose, called a rhinarium, is used to detect chemical changes in the water that indicate the presence of prey. Once prey is detected, the seal chases it with great mobility and speed. Because its blood contains large amounts of hemoglobin, which stores oxygen, it can stay underwater for as long as 20 minutes. When it dives, its heart rate slows to save oxygen.
Gray seals spend a large part of their lives hunting in the ocean. Still, they do haul out (come ashore) to rest and to breed. Most gray seals haul out on rocky islands, but they can occasionally be seen on sandy beaches. Gray seals are abundant in the cold northern Atlantic waters off Canada, Greenland, and northern Europe. They can be distinguished from common seals by their larger, more defined noses. Some countries have coastal nature reserves from which seals can be observed.
Gray seals mate between September and December. Females came ashore to give birth to pups conceived the previous year. Since mating takes place soon after the pups are born, males haul out at the same time and fight to establish breeding territories. The female gives birth to a single pup which she suckles for 14 to 17 days. Pups are born with creamy white fur that is soon replaced with gray fur. Three weeks after giving birth, the female comes into estrus (is ready to mate) and loses interest in her pup. The older, more experienced bulls dominate small groups of females which they mate at random. Although the females may conceive, the development of the fetus is delayed so that birth will occur at the same time the following year. After mating, the females leave the breeding beach to search for food. Pups are left to fend for themselves.
Seals have been hunted by man for thousands of years. Their skins were used for clothing and their blubber was a source of oil for lamps. Many coastal people made seal meat a part of their diet. In more recent times, gray seal pups were killed for their white fur to supply to the fashion industry. Today, due to the efforts of conservationists, the fur is no longer so desirable. The slaughter of seal pups has almost completely stopped. Gray seals are not popular with everyone, however. Some fishermen claim they eat too many salmon and cod. But scientists say that the seals do not seriously reduce the numbers of these fish.
It lives in the northeast and northwest part of the Atlantic Ocean, as well as the Baltic Sea. Total polulation estimated at 120,000-135,000. Largest colony of 80,000 found near Great Britain. Protected by law in parts of Europe.

We got our information from the "Wildlife Fact File".


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