Grey Seal pups are born on isolated beaches in the autumn. Like other mammals, they rely on their mother’s milk for the first few weeks of life.
Coastal habitats are home to a small but select band of mammals. Several terrestrial species forage on the fringes of the ocean and a couple of species have amphibious feeding habits. Seals are mainly aquatic but can venture onto land, albeit awkwardly, whereas whales and dolphins are exclusively marine and would soon die on land.
MAMMAL LIVES
Grey Seal pups are born on isolated beaches in the autumn. Like other mammals, they rely on their mother’s milk for the first few weeks of life.
Along with birds, mammals can generate body heat and maintain a more or less constant internal temperature. This is obviously important for terrestrial species, but even more significant for marine mammals that live in permanently chilly surroundings. A thick layer of blubber acts as a superb insulator. All mammals, including the most marine of all – whales and dolphins – are air-breathers and must return to the surface of the sea periodically to replenish their oxygen supplies.
MAMMAL REPRODUCTION
In all mammals, fertilisation is internal and the embryo and developing infant is nourished via a placenta, in which it is implanted at an early stage. Young placental mammals are born with varying degrees of independence and maturity depending on the species involved. In seals, young are born on land, but with whales and dolphins birth occurs at sea and their young must be able to swim from the moment they are born.
TERRESTRIAL AND AMPHIBIOUS MAMMALS
Although widespread inland, a few terrestrial mammals such as Rabbits thrive near the coast. And, surprisingly, Hedgehogs are also common in a few places on the seashore. Amphibious by nature, Otters have adapted to a life on the seashore in parts of Britain.
Cumbersome on land, Grey Seals are in their element in water.
Streamlined and fast, the Minke Whale is the most likely whale species to be seen in British seas.
Seals give birth on land and their terrestrial gait is awkward and shuffling. In water, however, they are graceful and speedy, powered by flippers. They have well-developed eyes and prominent whiskers, and our two native species feed mainly on fish.
WHALES AND DOLPHINS
Whales and dolphins live aquatic lives although, of course, they still retain the need to breathe air at the surface. Movement is powered by a broad tail fluke, and fins and flippers assist directional control. Known collectively as cetaceans, their diet includes marine fish and plankton, depending on the species.
Hedgehog Erinaceus europaeus Length 23–27cm
Spiny, nocturnal animal. Usually feeds on invertebrates. Hibernates Oct–Apr. ADULT has spines (modified hairs) on back; erectile and an effective deterrent when animal rolls into a defensive ball. VOICE Pig-like squeal in distress. STATUS Foolishly, has been released onto many offshore islands. Feeds along strandline but also eats birds’ eggs and young. Eradication programmes operate in some areas.
Lesser White-toothed Shrew Crocidura suaveolens Length 8–12cm
Invertebrate-eating mammal that often forages on strandline. ADULT has grey-brown fur and white-tipped teeth. VOICE Inaudible to human ears. STATUS Introduced long ago to the Isles of Scilly, and Jersey and Sark in the Channel Islands. SIMILAR SPECIES Greater White-toothed Shrew C. russula (length 8–13cm) occurs only on Guernsey, Alderney and Sark in the Channel Islands. Pygmy Shrew Sorex minutus has red-tipped teeth; widespread but range does not overlap with previous two species.
American Mink Neovison vison Length 45–65cm
Unwelcome introduction from North America. Active predator of aquatic life and seabird colonies. Swims well. ADULT has a slender body and bushy tail. Fur is silky and usually dark brown. Male is larger than female. VOICE High-pitched calls when alarmed. STATUS Originated from fur farms (‘liberated’ animals and escapees) and now widespread.
Otter Lutra lutra Length 95–135cm
Sinuous swimmer with a bounding gait on land. Feeds mainly on fish. ADULT has a long, cylindrical body, with short legs and a long, thickset tail. Webbed toes aid swimming. Coat is mainly brown but chin, throat and belly are whitish. Fur has water-repellent properties: sleek in water but ‘spiky’ when dry. VOICE Mostly silent. STATUS Following past persecution, now recovering and recolonising former haunts. Fairly common on undisturbed coasts in N and W Scotland and Ireland.
Rabbit Oryctolagus cuniculus Length 40–55cm
Rabbit, black form
Long-eared, social, burrowing mammal. Lives in tunnel complexes called warrens. Mainly nocturnal or crepuscular; diet is vegetarian. ADULT has mainly greyish-brown fur with a rufous nape and pale greyish underparts. Long ears have brown tips, and tail is dark above and white below. Black forms are sometimes seen, especially on islands. VOICE Squeals loudly in alarm. STATUS Introduced; now widespread and common. Often abundant on coastal cliffs and grassland.
Goat Capra hircus Height 60–90cm
Domesticated animal with several feral populations. ADULT has a long, shaggy coat, often piebald or whitish. Male is larger and bulkier than female and has recurved, ringed horns. JUVENILE lacks horns. VOICE Warning whistle. Females summon their kids by bleating. STATUS Feral populations exist in several rugged coastal sites.
Minke Whale Balaenoptera acutorostrata Length 8–10m
(Pronounced ‘minky’.) Smallest baleen whale but still large and impressive. Tail is not revealed when animal dives. Feeds on shoaling fish. ADULT is streamlined, with a narrow, pointed snout. Upperparts are dark grey; underparts are whitish, and broad bands of paler coloration extend up flanks, these sometimes visible on animals at surface. Curved dorsal fin is set far back on body. Single ridge runs from nostrils to tip of rostrum. Has a diagnostic broad white spot or band on upper surface of flipper; easily seen in swimming animals. STATUS Favours relatively shallow waters of the continental shelf and regularly seen from land; Mull and W Ireland are hotspots.
Fin Whale Balaenoptera physalus Length 18–22m
Second only in terms of size to Blue Whale B. musculus. Uniquely, has asymmetrical markings on head. Fast swimmer, catching shoaling fish. ADULT has a slender body with a narrow, pointed head. Body is mainly dark grey, palest on underparts and throat. Right side of lower jaw is whitish (as are front half of right side of baleen plates and tongue), whereas left side is same colour as rest of body. Single median ridge extends from nostril to tip of rostrum. Flippers are relatively long. Dorsal fin is curved, rather large and set a long way back. Tailstock is thick and tail fin is large. STATUS Mainly oceanic but sometimes seen in relatively shallow inshore waters. W coast of Ireland is a hotspot.
Humpback Whale Megaptera novaeangliae Length 12–15m
Large cetacean that is often active at the surface; breaches and engages in flipper- and tail-slapping on water surface. Feeds on shoaling fish and krill. ADULT has a bulky yet streamlined body; broad head is covered in lumpy tubercles. Pectoral fins are long and mainly white; dorsal fin is short and stubby. Tail is typically dark above and white with black markings below. Before a deep dive, arches its back strongly and tailstock and fluke come clear of water. STATUS Tolerates comparatively shallow seas if feeding is good, and hence is sometimes seen from land. Regular off W Ireland, mainly in winter.
Long-finned Pilot Whale Globicephala melas Length 4–6m
Long-finned Pilot Whale ‘spy-hopping’
Medium-sized cetacean with distinctive head and dorsal fin shapes. Lives in sizeable groups (pods) and feeds mainly on squid. Head, back and dorsal fin are visible at the same time when cruising at surface. ADULT is mainly blackish with a greyish saddle-shaped mark behind dorsal fin. Has a thighbone-shaped white mark from throat to vent, seen only when breaching. Head is blunt-ended, forehead is domed, and flippers are long and sickle-shaped. Dorsal fin is broad-based and curved. STATUS Widespread in NE Atlantic and occurs regularly in British and Irish waters; sometimes seen from land.
Risso’s Dolphin Grampus griseus Length 3–3.5m
Large, blunt-nosed dolphin. Lives in pods of 3–15 animals. ADULT is greyish brown overall, darkest on dorsal fin, flippers and tail, and palest on face, throat and belly. Older animals become very pale and marked with criss-crossed white scars. Head is blunt and forehead is split down middle by a deep crease. Dorsal fin is tall, pointed and slightly recurved. Flippers are long and narrow, and tail fin is broad. STATUS Regular in coastal waters, mainly off W Britain.
Killer Whale Orcinus orca Length 4–9m
Killer Whale, mother and calf
Killer Whale, male
Distinctive and well marked. The largest dolphin. Lives in pods of 5–20 animals. Feeds on fish, seals and other cetaceans. ADULT male has blackish upperparts with a saddle-like grey patch behind dorsal fin. Underparts are white and band of white extends onto flanks. Also has a white patch behind eye. Dorsal fin is up to 1.8m tall. Flippers are paddle-shaped. Adult female is smaller, with shorter dorsal fin. STATUS Occasional in British waters. Seen close to land if feeding is good.
Short-beaked Common Dolphin Delphinus delphis Length 1.8–2.3m
Our most regularly encountered dolphin. Lives in schools of 10s or 100s. ADULT is overall dark grey above and whitish below, with a broad, tapering yellow band on flanks from eye and mouth to just behind dorsal fin; grey band continues along flanks towards tail. Overall, yellow and grey patches resemble an hourglass. Flippers are narrow and black, with a black line running forward from base to throat. Dorsal fin is broadly triangular and slightly curved. STATUS Mostly oceanic; typically seen from boats, but sometimes from headlands in the W.
Bottlenose Dolphin Tursiops truncatus Length 2.5–4m
Bulky dolphin. Lives in schools of 3–4 animals. Diet includes fish and crabs. Playful at the surface. ADULT is greyish brown overall, darkest above and palest on throat and belly; mid-grey band is sometimes seen on flanks. Beak is rather short and blunt, with lower jaw extending beyond upper one. Flippers are rather long and pointed, and dorsal fin is tall, curved backwards and almost shark-like. STATUS Some individuals are pelagic, while other groups favour coastal waters. Moray Firth in Scotland and the Shannon Estuary in Ireland are hotspots.
Harbour Porpoise Phocoena phocoena Length 1.4–1.9m
Our smallest cetacean. Lives in groups of 3–15 animals. Playful at the surface. ADULT has a stout, streamlined body, blunt head and no beak. Flippers are small and oval, and dorsal fin is triangular. Tail fin is broad. Upperparts are mainly dark grey, while underparts are whitish. STATUS Favours inshore waters, including estuaries, river mouths and sheltered coastal bays. Moray Firth and the Inner Hebrides are hotspots.
Common Seal Phoca vitulina Length 1.2–1.9m
Common Seal, male
Common Seal, female
Common Seal, pup
Has a ‘friendly’-looking face. Hauled-out seals are easy to observe. ADULT is greyish brown but variably mottled with darker spots. Underside is paler than upperside. Dry coat looks shiny if dusted in sand. Bridge of nose has a concave outline (convex in Grey Seal) and muzzle is blunt, creating a dog-like appearance. Seen from front, nostrils are close together at base and splayed in a V-shaped fashion (separated from, and more parallel to, one another in Grey Seal). Front flippers have claws and powerful hind flippers effect propulsion when swimming. Males are larger and heavier than females. JUVENILE (pup) is born with a marbled grey-brown coat. VOICE Mostly silent. STATUS Favours sheltered seas. Widespread on E coast of England and around Scotland and Ireland generally. Easiest to see on N Norfolk coast, especially at Blakeney Point.
Grey Seal Halichoerus grypus Length 2.2–3.2m
Grey Seal, bulls fighting
Grey Seal, female
Grey Seal, female
Grey Seal, pup
Bulky seal with a proportionately large head. Inquisitive in the water. Hauls out for long periods. ADULT is greyish overall with dark, blotchy spots; has fewer, larger spots than Common Seal. Males are larger and darker than females. In profile, looks ‘Roman-nosed’: bridge of nose is convex, more pronounced in males than females. From the front, nostrils are distinctly separated and more or less parallel to one another, not V-shaped. Fore flippers have sharp claws and hind flippers propel the animal through water. JUVENILE (pup) is born with white fur; moulted after a few weeks. VOICE Low, moaning calls. STATUS Often found on rocky shores; tolerates rough seas and heavy waves. Widespread on W coasts and locally in the North Sea. Spectacular views can be had of the breeding colony at Donna Nook in Lincolnshire.