Guillemots and Razorbills
Guillemots and razorbills are members of the auk family. They breed in significant numbers on Ramsey, arriving in March and leaving in mid July.
Both species are descended from a bird called a great auk which is now extinct. The great auk was considered to be the northern hemispheres equivalent of a penguin, a consideration which is very apparent in the appearance of the guillemot and razorbill. Unlike a penguin, both the guillemot and razorbill are capable of flight, however, their wing spans are very small in comparison with the size of their bodies. This gives them a very inefficient high energy wing beat. Their wing size and shape renders them far superior swimmers and divers than they are fliers, often diving to considerable depths.
Both birds only come to Ramsey to breed, choosing to spend the rest of the year on the surface of the water, where they feel much more comfortable. If approached, they will often dive and swim away from danger rather than taking off.
Razorbills are the smaller of the two. They are black and white in colour, identified by a blunt black beak. Razorbills tend to choose breeding sites on small ledges which are tucked away under overhangs or around cave entrances and as a result, tend to breed in smaller colonies. This provides them with some protection from larger predatory birds such as greater black back gulls, peregrines and ravens.
Guillemots are larger, brown and white in colour and have a pointed beak. Guillemots breed on long narrow ledges preferably on sheer cliffs where they will cram as many birds as they can onto a ledge, in the hope that this strategy with prevent predatory birds with larger wing spans from landing. As a result they tend to breed in much larger colonies.
Both birds have very similar breeding habits. Neither will build a nest, laying a single egg directly onto the rocky ledges. The adult birds will then incubate the egg on their feet taking the incubation and feeding of the chick in turn. As they feel much more vulnerable on land than on the water, the adult birds will leave when the chick is only about 2/3 the size of the adult bird and cannot fly properly.
The chick will have to jump of it’s ledge into the water and follow the male bird out to sea under the cover of darkness to avoid predation. Once out on the water they are reasonably safe, because although they won’t be able to fly for a number of weeks they can both swim and dive well at this stage.
Puffins are also members of the auk family. Unlike the guillemot and razorbill they do not breed on Ramsey at the moment, but can be found on Skomer island in large numbers and in a smaller, younger colony on the North Bishop. They will arrive in April and leave as late as mid-August. The puffin is easily recognisable, with it’s brightly coloured beak (present only during the breeding season) and bright orange feet. Like it’s cousins, the puffin is a superior swimmer and diver than it is flier. Unlike guillemots and razorbills, the puffin will nest on land in a burrow. For this reason, their breeding grounds are limited to those where land predators are not present.
Fulmar Petrels are also visitors to the island, only inhabiting Ramsey for a small portion of the year in order to breed. Of all of the visiting seabirds that lay their eggs on the island, the Fulmar is here for the longest, arriving in April, leaving towards the end of September. It will take over a hundred days between the fulmar laying an egg and the chick fledging.
The fulmars are members of the petrel family, hence a relative of the albatross. The reason why the nest on the island for so long is because when their chicks leave their nests and head out to sea, they will not return to land for around 5 years. They will only come ashore when they have matured and it is time for them to breed themselves.
They have a number of interesting features that allow them to stay out at sea for so long. One is a very economical, straight winged gliding flight which enables them to cover great distances with very little effort. Another is the fact that they have twin nasal tubes on their beaks which are thought to act as a desalination plant enabling them to drink sea water. In addition their feet set far back on their bodies, ideally placed for taking off from the surface of the water.
Although very adept landing and taking off from the water, the fulmar will find it very difficult to land on the cliffs where they have their nest sites. As a result they have to choose very open accessible nest sites for ease of landing which would potentially leave them open to predation. However, the fulmar petrel has developed a highly effective self defence mechanism which takes the form of projectile vomiting their stomach contents at any predator that threatens them, unsurprisingly deterring the majority of predators.
The gannet is the largest of the British seabirds and has an almost 6 foot wingspan. They nest on Grassholm island which hosts approx. 39,000 nesting pairs (10% of the worlds population). They have a highly adapted hunting technique; they can spot their prey from up to 100 feet in the air and will dive from this height. They pull their wings right back into an arrow shape behind their body a split second before they hit the water at speeds of up to 60 mph. In order to protect themselves from the impact with the water they inflate air sacks in their head and body to absorb the shock. Circling gannets can often be a good indicator that there are cetaceans present as they take advantage of fish being hundred and pushed near to the surface.
The kittiwake is the smallest British gull to breed on Ramsey. They choose nest sites around caves for protection, however they are heavily predated upon, particularly by the Greater Black Backed Gulls. The Kittiwake is named after its call and is the only cliff nesting seabird that makes a proper nest out of wet grasses, saliva and mud.
The manx shearwater is the only visiting seabird to this area that migrates to the southern hemisphere for the winter; they over winter off the coast of Argentina. Over half the world’s population of manx shearwaters breed on Skomer, Skokholm and Ramsey. They are burrow nesters and very clumsy on land which makes them very vulnerable to predation. Because of this, one of the pair will stay down the burrow with the chick whilst the other goes out to sea fishing. They leave at dawn and return at dusk, not risking the final flight to their burrows until darkness has fallen to avoid being seen by potential predators. You won’t see a shearwater near land during daylight hours. Sometimes 30,000 birds an hour can be seen off the headlands heading to the islands as darkness falls. They will fly low over the water, wing tips shearing the surface of the waves, harnessing the ground affect for a highly efficient flight. It is from the method of their flight that the name ‘shearwater’ is derived. They can fly up to 50mph with scarcely a wing beat and easily travel millions of miles in the course of their life span.