British marine mammals

The gray seal


Grey seals are the largest breeding seals found in the U.K. Half of the world's population of grey seals are found around British coasts, and numbers here have doubled since 1960. In the autumn, females congregate at traditional pupping sites called rookeries. Pups weigh 14 kilograms at birth, but since their mother's milk contains 60% fat, they quickly balloon and develop the blubber layer essential for maintaining body temperature out at sea. When feeding, these seals can dive to a depth of 70 metres. A large colony of gray seals live off worms head we have had many encounters of these beautiful creatchers from the mumbles pier and on the Gower coastal cliffs. seals are coincided top of the food chain in British but we occasionally get Orcas who come down from the north to feast on seals.      

sardines are one of seals favorite food

Bottle nose dolphin 


Physicality 

The bottle nose dolphin which is often refereed to as the common dolphin is robust compared to other species of dolphins. It grows to be 8-12 feet long and can weigh up to 1,430 pounds. The neck of the bottle nose dolphin is very flexible because 5 of its 7 neck vertebrae are not fused together. The upper part of the body of this dolphin is light gray to slate gray and fades to lighter shades on the sides and then pinkish gray on the underside. Shades can vary greatly among the species, however. The bottle nose dolphin has 18 to 26 pairs of teeth in each side of its jaw. Each tooth is sharp and conical shaped. The dorsal fin, located near the middle of the back is slight curved or falcate. The flippers are of average size and pointed while the flukes (or tails) are broad and curved with a median notch.

Breeding

Females can become sexually mature any time between 5 and 10 years old. The males become sexually mature at 10 years old. Breeding and birthing take place all year long. In some areas of the world more bottlenose dolphin calves are born during spring and fall then in the summer or winter. Gestation or pregnancy lasts for 12 months. Baby calves will nurse for 12 and 18 months and stay with their mothers for 3 to 6 years. In the wild bottle nose dolphins usually live about 45 to 50 years.

Diet

The adult bottlenose dolphin can eat 15 to 30 pounds of each day, normally hunting alone but occasionally hunting cooperatively in a group with other dolphins. They eat a variety of food but mainly fish and sometimes squid and crustaceans.

Habitat

Bottle nose dolphins live in temperate and tropical water worldwide. They are not seen withing 46 degrees of the north and south polls where the water is colder. Some dolphins live near coasts and others off shores. These are called ecotypes. There are more dolphins of the coastal ecotype then the offshore ecotype. Dolphins are often seen in bays, lagoons, harbors, estuaries, and the mouths of rivers.