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Sea
Mammals around Fair Isle
The waters around the
Shetland Islands, including Fair Isle, are some of the richest in the whole
of Europe for sea mammals, with 21 species of cetaceans (whales, dolphins
and porpoises) and five species of seals recorded in the region. Although
some are scarce and irregular, sixteen cetacean and two seal species have
been seen in the last few years.
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Killer Whale off South Lighthouse, June 2002
Photograph by Glen Tyler |
For many visitors to
Fair Isle, their first introduction to cetaceans will be the boat crossing
on the ‘Good Shepherd’ from Grutness. If weather conditions are good and
the sea is calm, there is every chance of seeing small schools of
White-beaked Dolphins, which commonly come to the vessel to bow-ride and
sometimes large schools of Atlantic White-sided Dolphins occur too. The
strong tides that pass around Sumburgh Head frequently attract large shoals
of fish in summer and this in turn attracts several species of dolphin and
whale, making it one of the premier sea-watching points in Europe. The best
time for seeing cetaceans is between May and October, partly because sea
conditions are more favourable then for spotting animals, but also because
several species appear to move into coastal waters during the summer when
food supplies in the area are most abundant.
Since 1992, up to
three Humpback Whales have been seen off the coast of
Shetland,
particularly south of Sumburgh Head, mostly in June and July. Although
around 6,000 ‘Humpbacks’ live in the North-west Atlantic, the population in
European seas appears to number no more than a few hundred animals. After
centuries of over-hunting, the species has become very scarce and indeed
between 1928 and 1966, there were no confirmed records in British waters.
Since then, there has been a marked increase in sightings, particularly in
Shetland, heralding a possible come-back for this species, and Sumburgh Head
has become the most likely spot in all of Europe from which to sight this
rare whale.
In summer, Shetland
has one of the largest populations of Harbour Porpoise in Britain and this
is the species most likely to be encountered from the ‘Good Shepherd’,
particularly around the ‘roost’, just south of Sumburgh Head. Porpoises can
be seen in all months of the year, but as with other cetacean species, most
sightings are during the summer months, particularly in August and
September. The commonest species of whale seen in these waters is the Minke
Whale. It also occurs throughout the year, but with peak frequencies
between June and September. Usually only single animals are seen, mainly
within ten nautical miles of Sumburgh, although the species has been seen
regularly off
Fair Isle
itself during July and August.
One of Fair Isle’s
specialities in the cetacean world is the Killer Whale or Orca. Small pods
are seen almost annually off the coast around the end of May or in June.
They have been sighted coming right into both North and South Haven,
possibly in search of unsuspecting grey seals! They are also recorded
regularly from the ‘Good Shepherd’ mainly around Sumburgh Head. Some of the
same individuals have been recognised from year to year, by characteristic
nicks in the dorsal fin.
The Risso’s Dolphin is
a large dolphin that is sometimes mistaken for a Killer Whale at a distance
because the adults have a tall dorsal fin, resembling a female Orca.
However, at closer quarters it is easily distinguished by its overall pale
grey or even white coloration, often heavily-scarred with pencil-like
scratches. It also has a rounded forehead. Small pods are sometimes seen
off Fair Isle, though the species is most likely to be seen along the south
coast of Shetland mainland, usually between July and October but
particularly in August.
The most common
dolphin in waters around Fair Isle is undoubtedly the White-beaked Dolphin
and this is the species most frequently sighted from the ‘Good Shepherd’.
It is best distinguished from its close relative, the Atlantic White-sided
Dolphin, by the white flank markings which extend over the back and behind
the dorsal fin. The white beak may also be seen at close quarters, when the
animal is bow riding. White-sided Dolphins are much less frequently seen,
but when they do occur, they tend to arrive in large schools that number
tens or occasionally hundreds of individuals. They normally live offshore
close to the continental shelf edge, coming into Shetland waters
periodically in pursuit of shoaling fish such as Herring or Mackerel.
White-sided Dolphins have a discrete long white oval patch on the flanks
from which leads a narrow ochre band. Both species can grow to 12-13 feet
in length and on seeing them for the first time they are often mistaken for
whales like ‘Orcas’.
Another normally
pelagic species that sometimes comes into Shetland waters in pods that may
number tens or low hundreds of individuals is the Long-finned Pilot Whale,
which in past centuries were driven ashore for their meat, much as they do
in the Faroes today. It is only rarely seen from Fair Isle, but there have
been occasional sightings from the ‘Good Shepherd’, mainly in late summer.
Fair Isle has a small but easily observable
breeding population of Atlantic Grey Seals. Most people will spot them
first bobbing about in North Haven or hauled out on the rocks at low tide in
South Harbour and around the South Light. The pups are born mainly during
October, the most favoured beaches being at North Gunnawark and Muckle Geo
o’ Hoini, although Guidicum is also popular and pups can be born on any of
the small rocky beaches of the north and west coasts. Most of these are
below tall cliffs and being relatively inaccessible are little disturbed by
humans. Because seals can move between beaches from an early age, counting
the numbers produced each year can be difficult. Whole-island counts are
best done simultaneously, and recent attempts have provided an estimated
annual production of around 100 pups for the island.
Common Seals can also be seen from Fair Isle,
usually in South Harbour, although this species doesn’t breed on the island.
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