A male can grow up to 3.0M, females up to 2.0M and a newborn up to 0.9M in length. The lifespan of a female is 35 to 45 years. Whereas, the lifespan of male = 20 to 25 years. These seals have a large robust body, short thick flippers with long slender claws and large heads.
Males develop a robust neck & chest with prominent skin folds and wrinkles and tend to be uniformly dark brown-grey with light blotches, whilst females & juveniles are lighter with dark brown blotches. Females reach sexual maturity at 5-6 years and give birth to a single pup between September and December each year.
About 17 are estimated to be born along the C.M.H C. each year. Gestation lasts for 8 months with a delayed implantation period of 3-4 months thus the pups are born a year after conception around the same time as the breeding season and are suckled on a rich fatty milk (about 3 ltrs a day).
The seal pups can triple their body weight in just 2 to 3 weeks, after which, they shed there milky white fur coat and are off to fend for themselves. There are estimated to be over 4,700 Atlantic Grey seals in the west coast Wales area. Approximately 92,000 are estimated to live in the UK.
On the cruise, they can be seen hauled out on the rocks along the coast whilst resting and basking in the sun but they do spend 80% of their time submerged in the water. They can stay submerged for up to 8 minutes on these dives as they take in large amounts of oxygen and store it in blood and muscle tissue.
They stop water entering their lungs by closing the nostrils as a reflex action when diving and by closing the airway to the lungs with the tongue and the soft palate. They feed mainly near the sea floor on a wide variety of fish such as whiting, bass, salmon, sewin, sandeel, the odd squid and some crustacea.
