![A south polar Skua in flight.](https://media.guim.co.uk/f7bc3b7fc7f5d55c135123c6151ec11489128665/0_146_5400_3239/1000.jpg)
It has been a good autumn for seabird enthusiasts, especially those taking boat trips, known as “pelagics”, off the Isles of Scilly.
Among the usual sightings, a selection of shearwaters and storm petrels, came a real rarity: a south polar skua. As its name suggests, this species breeds at the opposite end of Earth to Britain, and has been recorded here only a handful of times.
Then, two weeks later, lightning struck twice. Britain’s second ever red-footed booby – a relative of the gannet – was also seen on a Scilly pelagic. Unlike most rare seabirds, which are seen only briefly as they pass through our coastal waters, this individual delighted birders by regularly roosting on Bishop Rock lighthouse, to the west of Scilly. Later that week, another member of its family, the brown booby, was seen off the coast of Fife.
All good news for keen seabird enthusiasts, but is this run of unusual sightings good for the birds themselves? Red-footed boobies breed on tropical islands and oceanic atolls, and although they do wander farther afield, they are rarely seen in temperate seas.
As the British Trust for Ornithology has suggested, unusually warm weather conditions – almost certainly triggered by the current El Niño event – are the likeliest explanation for a recent increase in sightings of these tropical birds. Whether this is a one-off, or an ominous sign of the climate crisis, it may be too early to tell.