I recently returned from a trip to Lewis, in the Western Isles of Scotland, a land of plentiful seabird life. One species in particular seemed ubiquitous when scanning the open sea, I don't think, on the ferry crossing, I recall a moment when at least one white cruciform shape, on stiff black tipped wings, was not in view. We'd see them fishing in the bay at Ullapool, taking advantage perhaps of the clear, calm water to better pick out the shapes of fish, diving on swept back wings, a single point plunging like a spear into the sea. We'd see them following the boat crossing the Minch, or, in good numbers, following every passing fishing boat. And during our time on the island, though we saw many other seagoing birds while scanning the horizon, Gannets seemed to crop up every day. And well they might, these magnificent birds have shown a consistent, albeit slow increase in population over the past 30 years (JNCC), and while there are no colonies on Lewis itself, Sula skeir, which takes its name from the Old Norse for 'Gannet Island' hosts a substantial colony, some 42 miles North of the Island. Still more nest on that outermost of the Western Isles, St Kilda, and the birds are capable of undertaking fishing trips of up to 270 miles.
Northern Gannets (Morus bassanus), to give them their full English name, breed only in large colonies, with several of these scattered around the coasts of Northern and Western Britain. The largest is at Bass Rock in the Irish Sea, the largest on the UK Mainland, and also one of the most southerly, is at Bempton Cliffs on the Yorkshire coast (RSPB) an RSPB reserve, where, in contrast to many other seabirds, their numbers continue to rapidly increase. A birder I met during a recent visit to Bempton told me he could recall when Gannets were relatively scarce at this site. Now they cover huge swathes of cliff, and fill the sky. Their fat chicks loafed on clifftop nests, heads lolling awkwardly on the rocks, huge black bills with sagging skin. They are odd, ungainly, and so relaxed many of them could be mistaken for corpses, causing Natty and I had brief anxious moments when we first beheld them in their clifftop domain. Gannet nestlings have a curious habit of looking dead when they are sleeping. Adults were constantly on the move, early in the season they could be seen ripping up grass from the clifftops to build their nests, or moving out to sea gathering fish to feed their chicks growing appetites. Non breeding juveniles share these clifftop nest sites, perhaps to learn the way of life of the colony, to observe the feeding behaviour of the adults, and learn the best fishing grounds.
Gannets are, despite their positive population trend, which defies that of almost all other British seabirds, Amber Listed by the RSPB, though the IUCN and Europe both consider the species 'Least Concern'. Though numerous and increasing, they really are almost entirely confined to large colonies, of several thousand breeding pairs. The nests in the colonies are surprisingly evenly spaced, typically just outside pecking distance, and peck, when faced with an intruder, they do indeed, with surprising brutality, comparable perhaps to Gulls and quite unlike more 'genteel' species like Auks. Wandering Gannet chicks have been seen killed by their neighbours when straying too far from their nests (Nicholson). Sometimes they even peck their partners when they arrive back from fishing trips, before pair recognition occurs and they bond again with noisy displays of bill rubbing, which Adam Nicholson describes as a kind of play fighting. They make very good parents, with two out of every three chicks fledging successfully.
The reasons for their bucking the seabird trend is unclear, but they are adaptable, and more than happy to follow the fishing boats and grab any discards, something they do in impressive numbers. From the shores of Lewis seldom did a fishing boat pass by without a small cloud of white crosses following it. The tourist boat from Bridlington in Yorkshire makes spectacular use of this ability, throwing fish overboard when passing the big colony at Bempton, attracting an enthusiastic following of Gannets. The ability to feed on a range of pelagic fish of different sizes, rather than be limited to Sandeels like the struggling Auks, probably makes them relatively resilient to local changes, as does the ability to travel many miles in order to catch them, though as to their breeding colonies they display some considerable fidelity to their fishing grounds during the breeding season. Gannets hunt by plunge diving from heights of about 25 metres, sweeping their wings back, their shape transforming into that of a short spear as they dive into the water, either siezing prey just below the surface, or, remarkably, powering down to depths of 30 metres or so, propelled on folded in wings, turning those supreme works of natural aeronautical engineering into simple paddles. Their heads and necks are powerful and reinforced in order to survive the impact, and serrations on the insides of their bills grasp the fish they catch.
Gannets have relatively few predators. Among their predators is man, with the colony at Sula Skeir attracting a group of licenced commercial hunters from Ness, near Lewis' Northernmost point, to kill a limited number of juveniles every year. Though it does not seem to affect the Gannet's conservation status, and I'll not dwell on this too much, the Scottish Society for the Prevention of Cruelty To Animals (SPCA) have described the hunt as 'Barbaric' and called for a ban. I am drawn to agree with them. Also among their enemies at sea are Great Skuas, which occasionally kill but more commonly just rob Gannets of their hard won food, and White Tailed Eagles, which are considered important predators of Gannets on the coasts of Norway, where both species are common.
There are more than one species of Gannet around the globe. The Cape Gannet (Morus capensis), often featured in documentaries about such phenomena as the Sardine Run, is distinguished from the Northern, our sort of Gannet, by the extensive of black on the tail and primaries. It breeds on six islands off the coasts of South Africa and Namibia, and is considered Endangered by the IUCN. The Australasian Gannet (M. serrator) is common and widespread, and increasing, along the temperate Southern coasts of Australia and New Zealand. The dramatically marked Boobies of Equatorial regions are slightly more distant relatives, retaining the generic name Sula. The Northern Gannet colonies around the British Isles are globally important, hosting as much as 55% of their global breeding population, and they can be seen, while sea watching, almost anywhere, especially in the Spring and Autumn, and at their colonies, of which Bempton is probably the most visited and most accessible, and, for me, something of an annual pilgrimage. There are not just Gannets to be seen there, but Puffins, Guillemots, Fulmars, Kittiwakes and others, as well as fantastic cliff views. They hang about there well into August, though the site is best visited from April to June for the full show. The photos here were all taken on a recent visit to Bempton, at the beginning of August, where the presence of the Black Browed Albatross, which eluded me, offered me the excuse to head down there and enjoy avian spectacle and some twitcher camaraderie.
Above all, I find Gannets stunningly beautiful. Sharp, pointed, and profoundly wild, but equally stunningly elegant. They are the largest seabirds regularly found around Britain, though their colonies occasionally attract even bigger guests in the form of lost Albatrosses which have ended up on the wrong side of the equator. Their pure brilliant white body feathers, those jet black primaries, the warm yellow ochre of the neck and head, their graceful, long winged glide as they pass by in their small bands, often incorporating both adults and black feathered juveniles. I love the joy of their pair bonding displays. And I find them somewhat hopeful, a rare success story among the troubled guild of piscivorous seabirds of the North Western Atlantic.
Excellent blog, very informative.
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