Tales from End to End
The Gannet’s Tale
by Ian Kendall
I can’t really imagine what its like to be a Gannet, Britain’s largest seabird, a six foot wingspan, the freedom to roam the oceans, the ability to dive at speeds of up to 60mph headlong into the water to catch fish, so instead this is going to have to be a Site Managers Gannets Tale!
Their history at RSPB Bempton Cliffs nature reserve is a remarkable one. The first nest was way back in 1924, although eggs weren’t laid until 1937 and the first chick didn’t appear until 1938. It is possible that these early colonists were wandering birds from the huge Bass Rock ‘Gannetry’ in the Firth of Forth, although we can never be sure. For a good few years after 1938 relatively few young were reared year on year at Bempton until the late 1960s and their meteoric climb in numbers since then is as follows: in 1970 there were 24 Apparently Occupied Sites (the slightly more scientific version of a valid nest!!) and by 1977 this had climbed to 169. In 1986 650 sites were counted and a mere four years later the thousand mark had been passed with 1035 occupied sites. Things then went exponential – in 1997 2501 sites were counted, 3498 in 2002, 6954 in 2008 and the latest count in 2009 of 7860!! Even though there are thousands upon thousands of other seabirds at Bempton, including over 37,000 pairs of Kittiwakes and almost 60,000 Guillemots it really is the Gannets that steal the show.
So that’s some of the hard facts, but what else do we know about this spectacular bird. Well we know that year on year they are consistently able to fledge the same number of young per pair. Only one egg is laid and it is long process for the adults to successfully rear the chick to fledging. Incubation of the egg, which is laid from very late March onward to late April, takes up to 45 days, but then rearing the chick to fledging takes a gruelling 90 days or so!! On average our Bempton birds successfully rear 0.84 chicks per pair, so in other words over six and half thousand chicks leave the ledges every year. No wonder the colony is increasing so rapidly.
Each year we also know that the pairs behave in the same way. There are a number of study plots and in each 50 pairs are followed through the season. Every year the same pair are always the first to return, the first to lay their egg and the first to hatch. Always fills us with joy when we see the season unfold in this way. Watching the antics of the chicks in these plots is fascinating too. One thing which always gets me is just how lazy the chicks are, quite often the larger chicks lie motionless on the nest, with head dangling over the side, looking for all the world dead – until, of course, and adult returns with a crop full of food, then they spring to life with huge enthusiasm.
We have a little insight into where the adults go now too. Using satellite-tracking telemetry, we were able to follow thirteen individuals last season and found that they forage within 100km of the colony and in the main head east south-east. One bird flew a staggering 308km and on average these adults spent 13 hours searching for food for their chicks. The fact that the bird mostly flew less than 100km is a good sign that food is, at this moment in time, plentiful, as for a number of other colonies birds fly much further in search of food. Then, of course, is winter and most move into north African waters and this is where the young stay for at least a year before returning. When they do return, up to 2000 of these adolescent teenagers can be seen hanging around on the edge of the colony and this is what gives us one of the best spectacles in the Birdwatching world. Thrilling views of these beautiful birds suspended in the wind at the tops of the cliffs only a few feet away from onlookers – absolutely a sight not to be missed.
Ian Kendall is Site Manager at RSPB Bempton: http://www.rspb.org.uk/reserves/guide/b/bemptoncliffs/