Life, around the clock

Storm Petrels are ideally camouflaged for their environment. From above their plumage is the same steel-grey of the Southern Ocean and when observed from the cliff tops around Bird Island they become all but invisible as they skim the surface of the waves. From below their white bellies blend perfectly with the clouds above them and only their characteristic undulating flight pattern identifies them amongst the swirling mist. These birds are some of our most elusive island residents, largely because most of their lives are spent at sea, coming ashore only to breed and to feed their chicks, usually at night. Monitoring the population therefore presents something of a challenge to our bird biologists and it was this challenge that found us making our way up the rocky stream bed away from the base late on Friday evening.  Armed with powerful torches and what looked like a couple of overgrown butterfly nets we were heading up to Gazella peak in search of ‘Stormies’. 

The long summer days here on Bird Island mean that twilight doesn’t arrive until late in the evening so we had plenty of time to enjoy our usual communal dinner before we packed up some warm clothes and headed out into the dark. The weather was perfect – usually still and relatively warm even for the middle of the austral summer. Through a break in the clouds the moon shone brightly over Willis Islands, too brightly in fact as darkness provides the best chance of catching birds. It did however serve to illuminate our path up the hillside as we negotiated our way amongst the many Fur Seals that have taken up residence for the duration of the breeding season. These seals are not generally that welcoming to their human neighbours and we found that night-time proved to be no exception. However as we slipped past them in the dark it seemed to me their growls and snarls had a greater element of surprise than of aggression and our passage through the rocks and tussock proceeded uninterrupted.

Arriving at the top of Gazella Peak, somewhat out of breath, we selected a broad rib of rock protruding from the gravelled slopes and settled down to wait. As if on cue, the moon slid behind a cloud and the darkness fell heavy about us. Gradually, as our eyes adjusted, we could make out the pale shapes of Antarctic Prions swooping above. These birds, slightly larger than the Storm Petrels, displayed the same characteristic flight pattern. They flitted like bats above us and as we illuminated them in our torch-beams they shone white against the darkening sky, lending a ghostly atmosphere to the proceedings.

As we perched on our rocky bench, occasionally shuffling and stamping to keep warm, I realised that I was about to witness an entirely new aspect of life here on Bird Island. On the grassy slopes below us the Wandering Albatrosses were settling down for the night, the Giant Petrels were quietly watching over their chicks and even the Skuas, usually so quick to screech their disapproval, seemed remarkably tolerant of our presence. But here on the scree-strewn slopes of Gazella Peak things were about to get busy. The first indication that something was afoot was a low ‘churring’ sound that seemed to be emanating from the ground beneath our feet. As I listened I found that I could distinguish the individual voices of birds that were stirring in their burrows. Gradually the noise increased and an occasional scuffling sound could be heard as the birds emerged into the night. We gathered our equipment and set off across the hillside in search of Petrels.

Jon soon proved himself to be an excellent bird-catcher. I watched as he chose a likely looking spot amongst the rubble that covered the hillside and waited patiently for the birds to show themselves. His tactic was to wait until the birds appeared at the mouth of their burrows and to illuminate them as they paused to assess their surroundings before taking to the air. This temporarily confused the birds and allowed him to descend upon them with his net. Once the birds were untangled from the net they soon became calm and submissive, allowing me to admire their delicate plumage and striking blue legs and feet. We transported them in cotton bags to the other members of the bird team who ringed and recorded them before taking feather samples and then releasing them back into the night.  Jon’s status as bird-catcher supremo remained unrivalled as I stumbled about in the dark in an extraordinarily unsuccessful attempt to help. The first bird that I caught turned out to be one that had only just been released, probably still a little shell-shocked form its experience and therefore an easy target for an amateur like myself. I apologised to the poor bird and sent it on its way. I moved too slowly in the next encounter and the bird had time enough to recover its wits aand take to the air. Still disorientated by my torch beam it flew straight into my legs and was soon scooped up, unharmed, by Jon.  Embarrassment prevented me from taking credit for its capture.  Despite some pretty enthusiastic net-waving I managed to catch nothing more than a few rocks and some bits of moss for the next couple of hours. At one point my net became entangled in the straps of my rucksack and I realised that I had managed to catch myself, but still no birds. Finally I was successful and carried my prize triumphantly back to the ringing station. ‘Great’ said Ruth ‘That’s 15 birds now, we are almost done.’ Jon had clearly been busy.

The mood of the group was light hearted as we made our way back down the hill towards base in the early hours of the morning. The moon remained hidden behind the clouds but by the light of our head torches we could make out the shapes of startled seals that we passed along our way.  As we got closer to the base we could clearly hear the calls of White-chinned Petrels in their burrows amongst the tussock. Often drowned out by the harsher shrieking of female Sur Seals and the pitiful replies of their pups I find this a soothing, almost musical sound. It is yet another reminder that the business of life on Bird Island continues around the clock.

One, two, three, four........

This week I have been counting things, lots of things: Spoons (48 if anyone is interested), bottles of gin (‘not enough’ I am told by concerned members of the team), vegetarian sausages, toilet roll (‘plenty’ much to everyone’s relief) and penguins (around two and a half thousand so far.) Counting seems to govern the life of those of us who inhabit Bird Island. All that can be observed must be counted.

The most recent counting frenzy has been the all-island count of Gentoo penguin chicks. These birds live in several large colonies around the island and every year members of the Penguin and Petrel team recruit other base members to help them count the youngsters before they fledge. At this time of year the chicks are starting to moult as they exchange their grey baby fluff for more elegant black and white adult plumage. They gather in large groups, or crèches, of several hundred individuals looking scruffy and forlorn as they wait for their parents to return from foraging trips at sea.  The first job of the counting team is to locate these groups and then to approach them without causing a penguin stampede. The colonies can often be smelled before they are seen - penguin guano is potent stuff and the smell of ammonia hangs thick in the air, it penetrates our clothes and stings our eyes. Even after showering on our return to base a distinct whiff can still be detected as we gather around the dining table. The next job is to split the colony into manageable groups for counting. This involves a sort of slow-motion recreation of ‘One Man and His Dog.’ Team-members approach the group slowly with arms outstretched as they gently herd the birds into the desired position. This causes pandemonium amongst the chicks who waddle at full tilt with their tiny wings outstretched, often tripping over each other in their panic to escape.  With shouts of encouragement (and often no small amount of derision) from their colleagues these penguin wranglers eventually isolate a manageable group of around two to three hundred chicks and the counting can begin. This involves picking an appropriate vantage point (not too close or it will panic the chicks) and using a hand-held counter to record as accurately as possible the number of birds in that group while being careful to discriminate between the older chicks and the few remaining adult penguins. When everyone has completed their count the tallies are recorded and compared. If the numbers are close then an average can be taken, if there is too wide a spread then the count must be repeated until the tally-keeper is satisfied. This can be a frustrating process, especially when the penguins start to move mid count. Sometimes this is a spontaneous re-organisation and on other occasions it is prompted by the arrival of a hungry Skua on the lookout for an easy meal in the form of a dead or weak chick. Always it causes consternation and blasphemy amongst the counters.  Once this group has been counted another batch must be separated and the whole process starts again. Occasionally a rogue penguin will break away from its designated group and attempt to join another. This is potentially disastrous as it can trigger a stream of defectors who will then mingle with the uncounted penguins and render all our careful segregation useless.  Careful watch must therefore be kept for chicks that look likely to break ranks and make a run for it. When spotted these birds are then dissuaded with much stomping, arm waving and verbal abuse (fortunately unintelligible to penguins.) To the casual observer it must seem that the whole team has taken leave of their collective senses.

The all-island count has been completed over 2 days and we await the final tally. As usual there is a sweepstake on the final count. The prize generally takes the form of a cake baked by the penguin team and shared with the whole group. Jon has won the last two years running, bets have been placed and we wait to see if he can complete a hat-trick.

Flight

My first glimpse of a Wandering Albatross is a moment that will stay with me forever.  Seen from the monkey deck of the RSS James Clark Ross it seemed to glide effortlessly above the waves. Riding the invisible currents it soared with its outstretched wings seemingly motionless and made the other smaller birds seem graceless in comparison.  As it followed the ship the Wanderer kept its distance, appearing aloof and majestic. Periodically it would catch the rising air and soar upwards, climbing far above us and then hang suspended for a moment in a stall turn that brought it plummeting back down towards the waves. As it flew low it seemed to brush the ocean with its wingtips. This mastery of flight made the plunging progress of the ship seem clumsy and slow.

A short while later I was privileged to be able to observe these birds at close quarters at their breeding grounds on Bird Island.  Sitting on the steep tussock above Evermann Cove I watched Black-Browed Albatross circling above their nests. The wind was blowing hard and the birds seemed to be enjoying the thrill of swooping close to their partners on the ground before pulling away and soaring back out over the water. Eventually through this wheeling maelstrom of birds came two Wanderers whose impressive wingspan far out measured that of the smaller Black-Brows.  They glided unperturbed through the busy airspace, subtly angling their wings to avoid collision. As I continued to watch I heard the rush of feathers above me as we were joined by a squadron of Skuas. These birds are smaller and more compact than the Albatrosses, their short wings and powerful bodies cut through the air like fighter jets. In contrast to the dramatic white plumage of the other birds Skuas are mottled brown for easy camouflage amongst the tussock and moss of the island. They quickly displayed their superior power and manoeuvrability as they sliced through the turbulent air. They seemed to come closer to certain disaster with every wing-beat but somehow avoided collision with both the hillside and the other birds. Though the Wanderers may be the icons of avian grace and elegance it is the Skuas who clearly hold air superiority on Bird Island.

On my way home that evening I was treated to a very different but equally thrilling aerial display. Tiny Storm Petrels live in burrows on the rocky slopes around the island and, though they are most active at night, they can often be seen flitting close above the ground around their nesting sites. These birds move so quickly that they seem to stay in the periphery of my vision and it is hard to observe them closely. They have an undulating flight pattern and seem to flit like bats through the evening light. Sometimes they can’t be seen at all but from their burrows they make their presence known through a characteristic ‘churring’ call that seems to emanate from the very ground beneath my feet. On a foggy day (of which there are many on Bird Island) these disembodied calls give an eerie quality to my walk home across the hillside.

Today we start the all-island Gentoo chick count so the whole team are heading off to the colonies around the eastern end of the island. This gives us the opportunity to admire the impressive icebergs that are now regularly passing by. These huge lumps of glacial ice seem to glow blue-green as they sail past on their silent voyage north.  There is a small ‘berg stranded out in Freshwater Bay and we have an excellent view of it from base. As it is slowly moulded by the tides it appears as an ever-changing sculpture that is our very own piece of floating art (I may be crazy but I think it has something of Henry Moore about it.) We were recently treated to a taste of this ancient ice when fragments were carried home by members of the team.  On close inspection I could see that it is full of tiny bubbles of air. These bubbles were trapped in the ice when it was first formed thousands of years ago and it is these that make glacial ice such an important part of climate-change research. As the ice slowly melted it cracked and popped as the air was released.  I couldn’t resist tasting a piece and found that it fizzed in my mouth a bit like popping candy. We also discovered (in very British style) that it is excellent in a gin and tonic!

Wandering Albatross

More from Bird Island

Life here on Bird Island continues to be busy for all team members. The unusually low rainfall has been welcomed by all except for Craig, our base technician who has been kept hard at work maintaining our water supply from the rapidly diminishing streams around the base. Fortunately things appear to be turning in his favour and the last few days have been blustery and wet.

The beaches are gradually getting emptier as the seals start to go back to sea. However they are certainly not getting any quieter as returning females call constantly for their pups who are now big enough to wander further afield when left unattended for days at a time. The seal team (Jaume, Jon and Hannah) are kept busy monitoring the seal populations both on the Special Study Beach and also on Freshwater Beach in front of the base. This year sees a higher than usual mortality rate amongst the puppies and we are beginning to suspect that hookworm infestation may be to blame. This is a common phenomenon amongst seals and accounts for a significant proportion of seal pup mortality around the world.  It is also possible that the krill stocks are further away from Bird Island than on previous years. This forces the females to make longer foraging trips which leaves the pups without food for considerable periods of time. Though this movement of krill seems to be natural and recurring phenomena it is impossible to tell at the moment whether it is the reason for the poor survival rate this year.  Jon and Jaume have noted my interest in these matters, along with my fascination with the physiology of diving animals and now seem intent on turning me into a seal biologist by the end of my time here. They have provided a comprehensive reading list including text books, lectures and scientific papers. Each trip across the beach with them provides an expert tutorial on marine mammals. While I am thoroughly enjoying their teaching and their enthusiasm for the subject I sincerely hope that there won’t be an exam at the end of it all! All the base staff will be out with the seal team on Tuesday as they do an annual pup survey of the local beaches. They weigh 100 pups at different locations on the same each year and use this to help them determine how the population is doing. We are hoping that the current weather (wet and wild) improves long enough for us to complete the survey in relative comfort. This survey will be done on a monthly basis through the rest of the season and promises to become even more of a challenge as the pups grow.

The penguins seem to be doing well, with Macaroni chicks hatching at the various colonies around the island. Many of the Gentoo chicks are now big enough to moult and get their adult feathers. These birds are still very much reliant on their parents for food and will not be ready to go to sea for a while yet. In the meantime they look very scruffy indeed as they lose their baby fluff. They hang around in large groups (‘crèches’) while their parents are at sea. When the parents return the chicks chase them around the colony frantically demanding food until they are finally rewarded for their efforts with a delicious meal of regurgitated krill.

The Wandering Albatross have finished their laying season and the Albatross team are kept busy patrolling the island recording the numbers and locations of the breeding pairs. This is such a big job (we anticipate that there will be in excess of 700 nests) that other volunteers from the base are gladly welcomed. It is the ideal opportunity for the rest of us to get out and about on the island and to spend some time with these impressive birds. Recently Jen and Steph (team Albatross) rescued a Wanderer that had a large fish-hook stuck in the side of its head. The poor bird was clearly unable to feed properly due to the obstruction in its gullet, but somehow had managed to find its way back to the island and, more amazingly, find its mate and build a nest. These birds form lifelong partnerships and though they travel alone, sometimes circumnavigating the whole globe in less than a year, they return to the same small island to breed. Usually the male bird arrives first where he will wait patiently for his mate. She will arrive a short while later and will pass low over the island before identifying her partner amongst the hundreds of other Albatrosses. After an affectionate reunion these birds will build a nest (usually by making improvements to an existing nest from the previous season) and then take turns to incubate a single egg.  The bird with the fish-hook injury appears to be doing well after his traumatic experience, but it showed us all how vulnerable these birds are to man’s activities around the world. They travel huge distances and their feeding grounds comprise some of the busiest commercial fishing grounds. Though the South Georgia Government insists that fishing tackle is clearly marked before issuing a license, many governments do not. This makes it impossible to track where the hook came from – likely many miles from Bird Island. These instances are fortunately rare, but every year many Albatrosses fail to return to their partners who continue to wait patiently for them.  Often the birds are killed or injured by entanglement in fishing gear or other flotsam and jetsam as they feed far from home. We hope that the work done here on Bird Island may go some way to increasing our understanding of our impact on these magnificent creatures and help us to devise more ways to protect them.

Black-Browed Albatross

Pintail Duck