Bird Island Diary — April 2008

30 April, 2008 Bird Island

April is a month of transition on Bird Island. For many of the animals that call this place home during the summer, April is the month that sees them depart to spend the winter months at sea, feeding and regaining condition in preparation for the next arduous breeding season. This year, April also saw the departure of our human summer visitors, as well as one of the long-term residents of Bird Island, after a thirty-month stint.

The month began with the wandering albatross census. We do this at the beginning of every month from now until the chicks fledge at the end of the year. All the eggs hatched during March, and the wee birds grow so quickly on their rich diet of oil, fed to them by the parent birds following foraging trips where they gorge themselves on fish and squid. The first unguarded birds were seen during the census – after only a few weeks, the chicks are too big to be guarded on the nest by their parents, so the big balls of fluff sit on their own on the nests, waiting for mummy and daddy to return to feed them. By the end of the month, all the chicks were unguarded and growing bigger by the day. It won’t be long until the chicks weigh more than their parents!

The macaroni penguins, which have been ashore in large numbers to moult at Big Mac and the other colonies, have started to head off again, and before the end of April they would all have departed to spend the winter at sea. However the gentoo penguins come and go throughout the winter, and this is one of the reasons that we see so many leopard seal visitors during the colder months! Most of the black-browed albatross chicks have now left, and the grey-headed chicks won’t be too far behind. It can be quite eerie to walk through the colonies that have been so noisy and active for over five months, to now see and hear no sign of life, just empty nests. Before they departed, we counted the chicks that were still surviving, in all the colonies to the west of the base. This can be compared with the number of breeding pairs back in November, to give some idea of pre-fledging breeding success. Derren has been very busy ringing and weighing the mollymawk chicks in the study colonies, prior to them leaving the island for several years.

Several vagrant seabirds have been spotted on our shores this month. On April 7th, Don photographed a royal penguin (Eudyptes schlegeli) at Big Mac. These birds look similar to the macaronis, but they breed on Macquarie Island, an Australian sub-Antarctic island on the far side of the Antarctic continent, so this one was a long way from home. We have also seen a number of chinstrap penguins (Pygoscelis antarcticus) on our beaches, especially during my daily leopard seal round, where it is quite common to see chinstraps on Landing Beach and the beach at Evermann Cove.

The female fur seals, which have been tending to the every need of their pups for the last four months (a relatively short lactation period for ‘eared seals’ such as these), have begun to abandon the island. The puppies have been getting more and more adventurous, swimming in the shallows just off the beach, and some venturing further out into leopard seal territory…! Soon there will be few fur seals remaining on the island, until they start to reconvene for the breeding season in November. It has been nice watching all the pups grow from the tiny black newborns into their beautiful, soft grey ‘adult’ swimming fur. They actually look like seals now! Some of them have tripled in size on the diet of rich milk from their mothers, and it can now be quite hard to tell the difference between this years pups and one- or two-year old animals.

I started my daily leopard seal round on March 31st, after the first sighting of a leopard seal for the season the day before. It is a nice walk of about 2km along the coast near to the base, and is done daily throughout the winter to keep an eye out for our visiting predators. If any are seen, I take photographs and together with Jaume Forcada at BAS, use the leopard seal database to try and match them to individuals previously seen on Bird Island. I didn’t see any leopard seals throughout the whole of April, despite the first sighting the month before, but after my first glimpse of these amazing animals, I am really excited for the time that they start to arrive in numbers – usually from the beginning of June. Nevertheless the walk is nearly always pleasant and provides many photographic opportunities.

We were blessed with some lovely weather at the beginning of April. After a largely wet and mild March we were due some sunshine, and the cool, clear days at the beginning of April, together with the easing-off of the summer workload, meant a fantastic opportunity to get out and explore. With only a couple of weeks to go, and still no definite departure date, Don made the most of this time to grab those last photos and go and visit all the magic spots on the island before he left.

One of his as-yet unfulfilled challenges was to walk from the most south-westerly point of the island, Pearson Point, to the most easterly accessible promontory, Cardno Point, via the tops of the five hills: Molly Hill (132m), Tonk (209m), Bandersnatch (Gazella Peak, 186m), Roché Peak (356m) and Gandalf (290m). Don and I set off as it got light one morning in bright sunshine to head down to Pearson Pt to do the traverse. It took most of the day, without rushing and with plenty of time to stop for photographs and tea breaks. Although only 5km from one end to the other, and with a maximum ascent of 356m (to the top of Roché Peak), the terrain on Bird Island is unforgiving, and the task of climbing through dense tussac over steep terrain belies this apparent straightforwardness. Ewan Wakefield, relieved to have finished the majority of his albatross fieldwork, met us at the top of Roché Peak with a flask of tea, and joined us on the final leg, over Gandalf and along the cliff tops on the north side of the island, to our finishing point overlooking South Georgia.

The weather turned chillier shortly before the ship visits around the middle of the month, but not before we’d managed to squeeze in a classic sub-Antarctic barbecue! On April 16th, the day that FPV Pharos arrived to take John and Ewan W, plus Fabrice the holiday-maker (going to Stanley with dental problems), back to the Falklands, we awoke to a light covering of snow and a heavy shower coinciding with the small boat coming ashore to collect them. Ewan had spent almost all of his time since his arrival on December 30th outdoors, doing fieldwork for his PhD. He has been looking at where black-browed albatrosses go during their foraging trips in-between visits to their chicks, and stomach temperature changes associated with feeding events. It is hoped to build up more of an idea of the kind of flight patterns associated with foraging trips, to see if this can be used to infer exactly where the birds are feeding.

The RRS James Clark Ross arrived two days later, on April 18th. This visit had several purposes: to restock our freezers for the coming winter (with no ship visits scheduled until at least September, and with four hungry blokes to sustain, this equates to a lot of food); to allow some maintenance to be carried out on some of the electronic science kit at Fairy Point macaroni penguin colony; and to collect Don, and all his belongings, for the long journey back to the UK. Most of the lads got to work unloading the cargo tender, while I was tasked with taking Mark Preston, an electronics engineer with BAS, over to take a look at the penguin gateway, along with Ruth, the ships doc, who had come ashore to give some important medical advice AKA for a ‘jolly’, with the intention of seeing some macaroni penguins! I felt very proud to show off the island on such a fine early winters day, with frozen streams and clear skies, and fat little wandering albatross chicks on their nests! Mission accomplished – Ruth managed to see one single macaroni penguin at the Little Mac colony (the rest having departed recently), and Mark removed part of the electronics at the penguin gateway for repair! Don took a group off the ship up to the meadows to see the albatrosses, and for one last walk before his departure.

Back at sea level, the ship was getting ready to depart having achieved everything that was required, and that meant it was time to say cheerio to Don. He’d arrived on Bird Island with Robin in November 2005, and had done an excellent job of looking after the fur seals for the last two years. Always great value on base, a hard worker and an excellent cook, we will miss Don on BI. He has been meticulous in his handover of the seal fieldwork to me, for which I am very grateful. How surreal it must have been to put on his boots in the boot room, as he had done so many times before, knowing that it would be the last time (for a long time, certainly) that he would do so. He stepped on to the Zodiac a little bleary-eyed (of course, nothing to do with his leaving party the night before!) after farewells to the folk remaining on the wee rock that he had grown to love. All the best for your return to the Motherland, Don!

So with the departure of the JCR it really felt like winter, but we were still short of one of our over-wintering team, and still had a summer visitor in our midst. Chris Martin had stayed on to try and finish some major projects, including the installation of our solar-powered water-heating array on the roof. With the solar tubes in place, Chris reckons that we will almost be able to cut out the use of the oil-fired boiler altogether, thus saving us considerable fuel usage, amounting not only to high cost but carbon emissions also. Chris admitted that he felt so relaxed and free of real-world pressures that he could actually see himself staying for the whole winter! But it was not to be – the Pharos called again at the end of the month, returning Fabrice to us and whisking him away to Stanley, via King Edward Point. It was good to get Fabrice back, and he brought with him goodies from the shops in Stanley and a box of clatch sent to us by the lovely folk at KEP!

Following the ship visits, the weather took a turn for the worse, and we had some of the heaviest rain that I have ever seen. The frozen streams melted, and, supplemented by meltwater from snow on the hills, became raging torrents. The stream that makes its way across Freshwater Beach (in front of the base) and enters the sea near the jetty became so powerful that it eroded a new route across the beach. We also saw many small landslides around the island (and, with binoculars, across Bird Sound on the hills of South Georgia). One such landslide occurred near to Johnson Beach, at the western end of Bird Island. A large collapse of mud, tussac grass and rubble landed on part of the beach where there were seals hauled out. I came across one young fur seal cow that was buried up to her neck, and managed to successfully dig her out, although there were doubtless more animals that could not be seen or be saved. Soon after, the rain abated the weather took a cooler, more wintery turn again, and we had another covering of snow before the end of the month. The good thing about Bird Island weather is that if it is awful, it doesn’t tend to stay that way for too long!

So, following a concatenation of circumstances both biological and meteorological, coupled with the departure of our summer personnel, now it is winter – and first impressions are very good indeed. It is quiet without all the others, and without many of the animals that dictate a large part of our lives during the summer, but we are all very relaxed and full of ideas and projects and other things to get up to over the winter. Roll on the arrival of the snow and the leopard seals!

My best wishes go to everyone back at home. I hope the approaching summer is warm and beautiful in lovely Scotland. With love,

Ewan

Zoological Field Assistant (seals)