The English Channel, a dynamic waterway connecting the Atlantic Ocean to the North Sea, provides a diverse marine environment. Among its inhabitants are seals, marine mammals well-adapted to coastal and estuarine habitats. These animals are a common sight along the Channel’s shores, contributing to its rich biodiversity.
Identifying English Channel Seals
The English Channel is home to two primary seal species: the Grey Seal (Halichoerus grypus) and the Common Seal (Phoca vitulina), also known as the Harbour Seal. They possess distinct features that aid in their identification.
Grey seals are typically larger, with adult males reaching up to 2.5 meters in length and weighing around 300 kilograms, while females are smaller at about 200 kilograms. Their most distinguishing characteristic is a long head with a sloping, often described as “Roman nose,” profile. Their nostrils are notably parallel. Generally grey, their coats display unique patterns of darker blotches and spots. Young grey seals are born with a white, non-waterproof fur coat and are unable to swim for several weeks, making them particularly vulnerable during this period.
Common seals, by contrast, are smaller, typically growing up to 1.6 meters long and weighing around 100 kilograms. They have a shorter head with a concave, or dog-like, facial profile. Their nostrils form a distinct V-shape. Their coloration varies widely from blonde to black, often appearing grey with dark spots; some in the Thames estuary can even appear orange due to iron-rich mud.
Common seal pups are born well-developed and can swim within hours of birth. When resting on land, they frequently adopt a characteristic curved “banana” position, lifting both their head and tail. While both species inhabit the English Channel, common seals tend to favor more sheltered shores and estuaries, often hauling out on sandbanks and beaches, whereas grey seals prefer exposed rocky coasts and islands.
Daily Life and Adaptations
Seals in the English Channel exhibit behaviors and adaptations that allow them to thrive in their marine habitat. Their diet is varied, consisting primarily of fish such as cod, herring, flatfish, and sand eels, but they also consume squid, crustaceans like crabs and lobsters, and occasionally marine birds. This adaptability in their diet allows them to utilize available food sources within the Channel.
These marine mammals are skilled hunters, capable of diving to considerable depths; grey seals can reach up to 300 meters, while common seals typically dive to about 50 meters. They can remain underwater for extended periods, with grey seals holding their breath for up to 16 minutes and common seals for around 10 minutes. Their keen vision and hearing make them effective predators in the underwater environment.
A significant aspect of seal behavior is “hauling out,” which involves coming ashore to rest, digest food, molt, and for breeding purposes. While at sea they are often solitary, seals gather in large groups when on land, which provides a measure of security. They can be quite particular about their chosen haul-out sites, often returning to historically established locations.
Conservation Efforts
Seal populations in the English Channel are subject to ongoing observation and conservation initiatives. Both common and grey seal numbers have shown upward trends in various parts of the UK, including the English Channel and the Greater Thames Estuary. Globally, grey seals represent a significant portion of the world’s population, with the UK being home to a substantial percentage. Both species are currently categorized as “Least Concern” by the International Union for Conservation of Nature (IUCN).
Despite these positive trends, seals face several threats. Entanglement in fishing gear, especially abandoned nets, and various forms of marine pollution, including plastics, chemicals, and oil spills, pose risks to their well-being. Human disturbance, such as dog attacks and reckless approaches by people, can also negatively impact seals, particularly mothers and pups.
Conservation measures are in place to mitigate these threats. Seals are protected under legislation, such as the Conservation of Seals Act 1970 in the UK. Efforts include establishing protected areas, raising public awareness about maintaining distance from seals, reporting injured animals, and organizing beach clean-ups to reduce marine litter. Supporting sustainable seafood choices also contributes to the health of the marine ecosystems seals rely on.