As the wildest seabird of the Wild Atlantic Way, the gannet evokes the soaring cliffs and fortress islands of the west, its spectacular plunge-dives piercing an ocean of vast and empty distances.
A big expansion of the gannet’s northern population, however, has followed the spread of mackerel to the Arctic circle, with breeding colonies now on the Svalbard archipelago. In Ireland, where numbers have more than doubled in half a century, an “overspill” has also been creeping northwards around the coasts.
The oldest colonies are at Co Wexford’s Great Saltee, Co Cork’s Bull Rock and Co Kerry’s Little Skellig. The most recent are on Co Dublin’s Lambay Island and Ireland’s Eye in the Irish Sea. And it’s here that hundreds of breeding gannets will have to reckon with the wind-slicing blades of giant, offshore turbines.
Dublin Bay alone is expecting some 60 turbines. A further five projects, fast-tracked with government approval, will line the east coast, stretching almost from Co Louth to Co Wexford. In the biggest of these, planned by a Norwegian-French consortium, up to 140 turbines will rise from the Codling Bank off Co Wicklow.
In studies of the possible impact on seabirds, gannets often head the list of “sensitive” species. This is less for the danger of actual collision as the cost to the birds of avoiding wind farms on long foraging flights to feed their chicks, or on seasonal migrations to and from their breeding colonies.
Foraging habitat
The cumulative loss of foraging habitat is what chiefly concerns BirdWatch Ireland, with its implications for breeding success and long-term impact on populations. The long stretch of whirling blades is also seen as one more pressure on other birds already amber- or red-listed.
One of these is the roseate tern, whose breeding colony on the lighthouse island of Rockabill, off Co Dublin, supports virtually the entire northwest European population. It is among the dozen “key species to be considered” in the environmental scoping report of the Dublin “Array” project.
Another is the kittiwake, threatened with “displacement” in the breeding season and “all year for collision risk”. A footnote also acknowledges “the variety of migratory wildfowl, waders and passage migrant species” using the bay. It’s these that bring spectacular winter flocks to the capital’s doorstep.
Studies at offshore wind farms are still too few in western Europe to offer enough hard data about the long-term impacts on birds. A wide-ranging review of “avoidance rates” for the Scottish government in 2014 noted “gaps in the data for key species such as the northern gannet and black-legged kittiwake”.
It concluded, however, that “birds very rarely pass close to the rotor blades”, even among the gulls that are more inclined to fly between the turbines. Geographical layout of a wind farm and spacing of its turbines are becoming crucial to the inevitable, marginal trade-off between energy supply and thriving bird populations.
Field guide
The gannet, as it happens, soars across the robust hardcover of a new field guide to Irish birds. In a substantially improved and updated new edition of a book first published in 1995, David Cabot has produced a guide of enduring usefulness and value. It will especially appeal to people with a general interest in birds and to young enthusiasts with their first binoculars.
Irish Birds avoids the irritations of field guides tied to classification systems or with superfluous pages of vagrant rarities. Its birds are those one is most likely to see in distinctive Irish habitats – gardens, farmland, woods, moors, coast. The illustrations show birds as they look, along with help on telling them apart in the field.
The 25 years since the first edition have been eventful for Irish birds. There are new breeding species – eagles, woodpeckers, egrets, the great skua – and ultimate, deadly declines of the native curlew, lapwing, corn bunting and more. Cabot charts the fortunes of each species, helped by the kind of meticulous fieldwork he helped to pioneer in Ireland; he was a founder of bird conservation NGOs that have mass memberships today.
They will, it seems, need to bring into everyday currency the new names for birds that Americans and others are already well used to. Thus, as this new guide has it, the great northern diver is now the loon, the guillemot the common murre and the Arctic skua is the parasitic jaeger.
The last, at least, is well deserved, as the skua most frequently seen along the west coast, chasing gulls and terns to bully them out of their fish.
