Birds in Pembrokeshire
No bigger than a pigeon and able only to shuffle on land, the Manx Shearwater is a master of ocean flight and a pelagic wanderer that can clock up 5,000,000 miles in its lifetime.
And, if it survives the many perils it faces during its long ocean journeys and its lengthy annual stay on land during the breeding season, when it is at its most vulnerable, it can live for over 50 years. One ringed bird was 55-years-old when it was recaught on Skomer, and it might well still be somewhere out in the wild North Atlantic today.
The European population of Shearwaters is estimated at between 280,000 to 320,000, and the Pembrokeshire bird sanctuary islands of Skomer and Skokholm hold the largest known concentration of these beautiful birds in the world, Skomer hosting 129,000 pairs and Skokholm 45,000 pairs.
Manx Shearwaters arrive at the Pembrokeshire islands in March for the breeding season and depart in October to return to their winter wanderings around North and South America between November and February. Birds ringed on Skomer and Skokholm have turned up at Lawn island, Newfoundland, Rhode Island, Argentina, Martha’s Vineyard and Chappaquiddick Island in Massachusetts, thus the round trip they make annually exceeds 20,000 miles. This does not take into account their meanderings in the North Atlantic in search of their food of herring, squid and small fish, which doubtless add a few thousand to the mileage tally.
These gracefully-shaped black and white birds nest in burrows made by rabbits or puffins on the clifftops and inland on Skomer and Skokholm, laying one white egg and brooding one chick between April and July. Very vulnerable on land and in daylight because their short, black legs are set well back and they can only shuffle on their white bellies, using legs, wings and bill, until airborne, they are mainly nocturnal as they can be picked off by predatory gulls and other birds in the open. However, they are very swift and graceful fliers and spend much of their existence at sea in all weathers catching their prey by diving from the surface or a short plunge from the air. During onshore autumnal gales many young birds are blown ashore and become disoriented, often landing in towns and villages as well as on beaches and clifftops, where they have to be rescued and relaunched manually at dusk or in the dark to return to their migratory flights. Although nocturnal, many birds from the islands can be seen off the west side of Skomer, particularly during the day, especially in inclement weather, while in the evening large numbers go into St Brides Bay and Broad Sound and can be viewed from Wooltack Point. Vast passages also move between the islands and distant feeding grounds in the early mornings and evenings. An ideal way to see them at close quarters, and hear their unique dove-like calls, is by taking one of the evening boat cruises from Martin’s Haven.