Bird Island Diary — March 2010
More weighing was carried out on Main Bay, this time it was the turn of the fur seals pups for their third and final time before they leave the island. This year was a good season for them too, as although numbers were much lower than normal the average weights of the pups were much higher than last year’s at 14kg. The albatrosses didn’t want to miss out on the weighing bonanza either and Claudia and I were kept active with daily visits to colony J to weigh the black-brow chicks at 80 days old and then later in the month we moved onto the grey-heads in colony E for their 100 day weighing. All this weighing helps us to assess the health of the wider ecosystem by quantifying the fitness of the higher predators.
This month saw the launch of an exciting joint project between BAS and the BBC, tracking a pair of wandering albatrosses over the next few months with small satellite transmitters taped to their feathers. These tags will give us daily updates of their positions, showing us where they are going to find food to feed their chick. Claudia and I fitted the transmitters to the pair nesting in Wanderer Valley, just behind the base in the middle of the month. The latest information can be seen on the BBC website where you can see a weekly diary of the status and activity of the birds and also other information about wandering albatrosses and our work here on the island. Across the island there have been increasing numbers of non-breeding Wandering albatrosses displaying in large vocal groups — the majority of these are young birds, yet to have paired up for a mate. It is a great sight to see and stunning to sit and listen to the bill clapping and sky calls of these magnificent creatures.
A hint of winter is in the air this month, with a few snow showers and icebergs starting to appear on the horizon, and a few of these breaking up and washing smaller bits into the bay for the locals to play on (that’s the animals, not us human inhabitants!)
We were lucky enough to get two different species visiting the island in March. The first of which was a sub-Antarctic fur seal on 16th. These more colourful relatives of our resident fur seals are occasional visitors here and this one was obliging enough to stay around for a few days, allowing everybody on the research station to get a good view and a photo or two.
On 24th we were lucky enough to play host to an even more unusual visitor to the island in the guise of an Antipodean albatross. This close relative of our wandering albatross has never been seen on the island before or anywhere east of Chile. This bird was ringed as a chick and was seven years old when she popped in here. She spent a couple of days on the ridge, but didn’t get too much attention from the local wanderers.
The end of the month saw a busy day for Claudia and me, ringing all the black-brow chicks in the study colonies. This will aid future research as they will be known age birds when they come back to the island to breed (in 8 years or so) allowing future generations of researchers to study them for the rest of each birds life. It also allows us to calculate how many chicks actually survive to return to the colonies as adults. The little chicks have a few weeks yet before they start to depart in the middle of next month.
The giant petrel chicks are coming along nicely and Stacey has been busy ringing the Northern chicks and taking their weights, bill measurements and fitting many of them with small GLS loggers to see where they go to between fledging and returning to the island. Towards the end of the month the older chicks had started to depart, looking very smart in their new slate-grey plumage.
Along with the giant petrel chicks, the fur seal pups are rapidly leaving Bird Island, after spending some time practising swimming in the waves and playing on the bits of brash ice that are blown into the bay. Some of the pups that are tagged every year at SSB have been seen at the far ends of the island, clearly on their way to pastures new! They have been seen with the gentoo chicks swimming in the sea and clearly enjoying the waves. Most of the gentoo chicks have now finished moulting, although there are a few funny ‘hair’ styles around. Along with the moulting adults there are some scruffy individuals about.
Our rapidly growing wanderer chicks are starting to be left unguarded by their parents now, with a few small and very vulnerable looking birds sitting alone in some oversized nests. This is all a part of their natural life cycle though, as now both parents head off to forage for food to bring back to the ever demanding and rapidly growing chicks.
Big Mac started to get busy again as the adults that left last month after finishing breeding returned to the colony to moult. The whole place looks like one big pillow fight at the moment, feathers everywhere, blowing in land from the colony and onto the Meadows.
A few clear nights and sunny days (a rarity this summer!) allowed us all to get out with our cameras and experiment a bit… Towards the end of the month we undertook the annual research station scrub down, a big job, but good to get done before all the summer folk leave so there are more people to help out. A few hours of scrubbing and hosing removed the worst of the grime from the building, most of which was a “seal level tide mark”, where the grubby little creatures rub themselves along.
On the 29th Stacey and I managed to get up La Roche one morning to watch a spectacular sunrise over South Georgia; a dramatic and fitting finale to my 2½ years on this unique and magnificent little rock in the South Atlantic.
Well, that’s all from me for this month and forever, I am sorry to say. The RRS Ernest Shackleton turns up here in the next few days to take me home via the Falklands, so farewell and hope you enjoy the future diaries from BI.