With what appears to be a baby boom in the seal colony at Blakeney Point’s, England’s largest gray seal colony, rangers have identified several melanistic peeps among newcomers to the National Trust Reserve this January. Located in North Norfolk, Blakeney Point has seen a significant increase in its peeping season yields over the past two decades, from just 25 puppies in 2001 to more than 3,000 in 2019. Most of these seal pips sport dusty white foggy coats that once helped them disguise themselves in the icy environment but failed to keep up to date with the changing winter landscape in a warm world. Now, as they lie on evergreen sand and gravel, they don’t mix so well.
It seems to be about one melanistic out of 400 gray seal dolls. Melanism is a term used to describe living things whose excess body darkens the tissues of the body and which can cause some animals to have some beautiful jet-black. It has been found in amphibians, reptiles, birds, and mammals, including our gray seal pips.
Rangers at Blakeney Point have spotted 10 such melanistic seals this peeping season, breaking 4,000 new incoming records in reserve (matching 1/400 figures). The seals come to breed in October-November and leave in January when the seals give birth to their young and wean them. Rangers used to observe the peeping season by walking among the animals, but this year they have been given a lot of baby speed they need to reconsider and come up with a safe strategy. The teams now monitor the activity of puppies in a particular area and use that information as an indicator of activity occurring throughout the colony.
The opposite effect of melanism is called leucism and it causes animals to appear abnormally paler than their peers due to the lack of pigments. Two close-shining examples of this were seen on the South Georgian coast of the South Atlantic Ocean where a pale penguin and a seal looked cold on the beach. leucism differs from albinism, a condition that leaves all pigments only white (and sometimes pink or red eyes), as it can produce an existence of pale gold.
The (Not so) gray seals have now left the matter, a representative of a national trust told IFLScience. Puppies stay with their mothers for weeks, which can lose about 65 kg (143 pounds) in the process of fattening their precious offspring. The little ones work thirsty and they drink about 2.5 liters of their mother’s milk every day, balloons weighing up to about 30 kg (66 pounds) in a fortnight. After the mothers return to the sea, the dolls work with her coat and confidence until she has the courage to follow suit a few weeks later.