19th July 2018
Established 1872. Online since 1996.

On the wing mallies return in numbers to take up residence in breeding season

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Fulmars are around Shetland for much of the year, but now their numbers are starting to build up prior to the breeding season.

Although a fulmar superficially resembles a gull, it belongs to the same family of ocean-going birds as the albatross, which spend much of their time on the wing. Like these larger relatives, the fulmar is superbly adapted for soaring stiff-winged over the waves for long distances. The hooked bill has prominent tube-shaped, external nostrils, and the build is more thick-set than that of a gull.

Also, the legs are set much farther back on the body so that a fulmar cannot take up a typical gull stance and can only shuffle around on land. On the water, or on the ground a fulmar needs to make a pattering run-up to take off. Once air-borne, a fulmar can “hang” on the air currents, taking advantage of its amazing manoeuvrability to hover at the top of the cliff.

Although fulmars were first recorded in Shetland waters in 1806, they did not breed here until 1879 when the first pair was recorded in Foula. At this time, fulmars only bred in St Kilda, but the birds seen at the Shetland haaf fishing were from colonies in Iceland.

Like the collared dove, the fulmar also rapidly expanded its range, a biological phenomenon known as “explosive spread”. From Iceland, fulmar colonies spread to the Faroes and then to Shetland. By the late 1890s fulmars were breeding in Papa Stour, Eshaness, the Ramna Stacks, Hermaness and Noss.

In 1939 J Fisher and G Waterston estimated the population in Shetland to be 22,000 pairs in 55 separate colonies, with almost half of the population breeding in Foula.

It is not certain which factors were responsible for this sudden increase, but possibilities are the increased availability of offal from whaling and fishing industries, or a genetic change which allowed the species to move into warmer waters. From Shetland, fulmars moved southwards to colonise Britain and Ireland. In addition to taking discards, fulmars also feed on zooplankton, small fish, squid, crustaceans and other marine invertebrates.

The Shetland fulmar population continued to increase until the late 1990s. Between the years 2000 and 2002 there was a 15 per cent decrease, although the islands still hold around 34 per cent of the UK breeding population. The Scottish population comprises 96 per cent of the UK population.

Fulmars are difficult to census as they do not build a nest, so it can be tricky deciding whether a bird is just occupying a site or incubating. Breeding sites are varied – high sea cliffs, low cliffs, inland quarries, ruins, road cuttings and even at ground level on uninhabited islands. Most fulmars hold territories by January, which they defend noisily, although the single egg is not laid until mid-May. Fulmars do not usually breed until they are 10-12 years old but they can live for 40-50 years.

The end of March has brought few notable migrants. A pair of goosanders were on Strand Loch on the 29th, while a male scaup was on Clickimin and 12 Iceland gulls in the Gremista area on the 28th. Elsewhere, there were a few records of robin, greenfinch, woodcock and wood pigeon. A large flock of 215 turnstone was counted in Sand­wick.

Highlights from Fair Isle for March include 256 skylark on the 5th, the first two bonxies on the 17th and the first wheatear on the 26th. There was an increase in the numbers of waders on passage and increasing day visits by guillemots and razorbills to their breeding colonies. Other migrants recorded on the island include short-eared owl, hen harrier, sparrowhawk, a pair of peregrines, goldcrest, black redstart, pied wagtail, wood pigeon, rook, chiffchaff, dunnock, linnet, chaffinch, robin, mistle thrush, blackbird, reed bunting and stone­chat.

Joyce J M Garden