Living the Wild Life

Seabirds and the Saltee Islands, Wexford

The Saltee Islands have a central place in the development of birdwatching and ornithology in Ireland. Obviously, they are very important for breeding seabirds but also are renowned for attracting 'falls' of migrant birds in spring and autumn and to add spice to the cake, the vast numbers of common migrants (swallows, thrushes, warblers) can include the occasional rare bird.... 'Yanks' (from America), 'Sibes' (from Siberia) and 'Overshots' (from the Continent). The latter include the likes of Hoopoes and Golden Orioles. The combination of seabirds, migrants and rarities makes sure that the island 'ferry' from Kilmore Quay is full on most weekend days from April to Autumn!

Great Saltee was the place one of the founding fathers of Irish Ornithology, Major Robin Ruttledge, 'cut his teeth'; he established a bird observatory there that operated between 1950 and 1962 and this, sort of, developed into the Great Saltee Ringing Station in 1977 which is still active today with Oscar Merne, a highly experienced seabird ringer, usually at the 'helm'. Oscar co-authored the best book there is on the island - something of a collector's item nowadays [see below], and he together with Clare Lloyd and, more recently Alyn Walsh, have monitored the island's seabirds in great detail.

Seabird 2000 was a wide-ranging survey, undertaken in the five year period 1998-2002, that attempted to count the number of breeding seabirds at all colonies in Ireland and Britain. The resulting dataset is widely accepted as the baseline for seabird population monitoring and the section below relies heavily on these surveys. Gannets were counted in an additional survey in 2004.

Gannet
The Gannet is the largest, and probably the most spectacular, seabird in Ireland. It also happens to be the one whose population is continually increasing and at the fastest rate. About two-thirds of Gannet pairs that get round to building nests manage to raise chicks to fledging - though the interval between nest building and fledging is long! They have no natural predators and hence their high success rate; failures are often due to squabbles and disputes between neighbouring pairs. As a big bird, they can tackle a wide variety of fish prey species from sandeeels to Mackerel. Recent research has shown that Saltee Gannets do not really specialise to any degree and take a bit of everything, On the other hand, those at Bass Rock in the North Sea, mostly take Mackerel and sandeels. To watch Gannets plunge diving on an inshore shoal of Mackerel is arguably one of the finest wildlife spectacles in Ireland. Coupled with this, the Saltee colony permits a closer approach to nesting birds that just about anywhere in the world! Go yourself and enjoy next summer. Herring Gull
Most people think Herring Gulls are the archetypal, boring old seagull! In fact they have just been put on the Irish Red-list of the most threatened, declining bird species. In the past 15-20 years about 90% of our breeding population have simply disappeared, and no one really knows the reason why. We now only have about 6,000 pairs in the country; the situation on Great Saltee mirrors this overall trend: in 1980 there were about 500 pairs and now not much over 50 pairs. There are a lot of ideas ('hypotheses') about these declines but few actual facts and because of their supposed commonness, no one until recently has bothered studying them. Amongst contributory factors are:

Better management of our land-fill rubbish dumps; recent hygiene practices now prevent gulls from getting at most of the rubbish -formerly a reliable source of food - much easier than fishing!
Botulism - Rubbish including much rotting food, in easy to tear black plastic bags, creates a suitable warm microclimate, for a toxic bacterium to flourish. This causes a sort of paralysis in gulls that commonly leads to a slow death by exposure (chilling).
Fisheries regulations - the mesh size of fishing nets is being increased to reduce catches of unwanted small fish and the practise of discarding of both fish offal and undersized fish at sea could also be declining, thus reducing another easy source of food for gulls and other seabirds.
All these and other factors could be behind the decline in Herring Gulls.

We certainly need to know more about this interesting gull. Herring Gulls usually lay three eggs and tend to raise one or two young on their cliff top territories.

Razorbill
Almost always out-numbered at cliff colonies by their common Guillemot 'cousins', Razorbills are the blacker-backed of the two larger, common species of auk and they have the chunkier bill with a stripe. Also, they bring several fish back to their young, cross-wise in the bill rather like Puffins whereas Guillemots bring a single large fish that mostly is carried inside the bill with only the tail 'sticking out'. Razorbills usually prefer a more enclosed nest site on the cliff ledges, perhaps behind a boulder or in a crevice, than the more packed Guillemots. They lay a single, large pear-shaped, often brightly coloured, egg; the majority of pairs manage to raise their chicks. These fledge 'prematurely' before they are capable of sustained flight, with one of their parents taking them to sea where they are much better equipped to evade depredation (by gulls), by their innate diving ability, whilst they finish growing!

Puffin
Despite appearing to spend a lot of time at the colony sitting around showing off their splendid bills, Puffins are much more private than the other auks and do most of their 'child-rearing' underground in burrows. Great Saltee supports the largest Puffin colony on the east coast, but they are in a somewhat similar situation to the Herring Gull, with their present population only a small remnant of what used to be present 100 years ago. Again, we are short of facts but the presence of Brown Rats at Saltee and elsewhere on other east coast islands (Lambay, Ireland's Eye) could prevent them from recovering even if other conditions remain favourable i.e. lots of food and potential nest habitat. Puffin burrows can be quite long if sufficient soil is present and a single white egg is laid. They are characterised by their habit of bringing beakfulls of sandeels back to their single chick which the parents eventually 'abandon' and force it to find its own way to sea. Those that survive the initial journey will spend several years out in the deep ocean before returning anywhere near their home colony.

By Dr Steve Newton, Senior Conservation Officer - Seabirds Birdwatch Ireland, 1 Springmount, Newtownmountkennedy, Co. Wicklow

Recommended Reading:
Lloyd, C.S. 1981. The seabirds of Great Saltee. Irish Birds 2: 1-37

*Lynas, P., Newton, S.F. & Robinson, J.A. 2007. The status of birds in Ireland: an analysis of conservation concern 2008-2013. Irish Birds 8: 149-166.

*Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. 2004. Seabird populations of Britain and Ireland. Poyser, London.

Roche, R. & Merne, O. 1977. Saltees: Islands of birds and legends. O'Brien Press, Dublin.

Items marked * are available from the BirdWatch Ireland on-line shop

Want to find out more?
www.birdwatchireland.ie
www.npws.ie
www.seabirdgroup.org.uk

 

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