Bird Island Diary — July 2006
With the Antarctic Darts Championship under our belts, midwinter done and dusted and no imminent birthday celebrations, July was always going to be a quieter month. I thought I would explain some of the sorts of things that keep us busy work wise during the quieter winter months, when many of our study species have left the island.
The three biologists (Donald, Helen and I) have been spending a lot of time in the lab analysing diet samples collected in the summer and stored for processing in the winter. These enable us to assess the type of prey that our predators (seals, albatrosses and penguins) are hunting. Most of the animals we study eat krill, fish or squid. By identifying and measuring squid beaks (the hard mouthparts of a squid), otoliths (fish ear bones) and the skeletons of krill (small shrimp-like crustaceans), we can tell from the diet samples what type and size of prey are being targeted by the animals on Bird Island and which types of prey, whether it be squid, fish or krill, are most important or depended on.
Above: Squid beak from an Albatross regurgitation (right), and tiny otoliths (left) from a seal poo. The squid beak is about the size of your thumb nail but they can be a lot bigger or smaller, depending on the size of the squid eaten. Otoliths are usually tiny.
So, many hours were passed in July in the lab, measuring and identifying these things and listening to music and even the radio thanks to the new internet connection!
Donald was also busy patrolling the beaches looking for Leopard Seals, recording them photographically to tell individuals apart and to get an idea of the number of leopard seals visiting us during the winter. In the summer, leopard seals migrate south to breed amongst the ice so we look forward to seeing them in the winter when they return. They really are quite ferocious if you catch them in the right mood, as the three zoologists (two zoologists and a vet....Helen) came to realise one day in mid-July, when we watched a leopard seal at close range mauling a small fur seal. It was the Antarctic equivalent of watching a lion kill on safari. Poor old fur seal. A leopard seal has got to eat but didn�t your mother ever tell you not to play with your food? On most of the encounters we have with leopard seals they are hauled out of the water on the beach or on an iceberg resting and digesting. Out of the water they are much more placid, don�t really move around a lot and are generally no harm to anyone. This gives a brilliant opportunity for Don to get close up with his camera and photograph the spots and markings that make individuals so distinctive. These identifying features allow us to monitor the local population.
These two leps were seen at the same place emerging from icy water in Everman Cove. I took the first picture (bottom) and Don took the second picture (top) in the same place about ten minutes later. We both assumed they were the same animal but later, after studying the photos it became obvious that they were different. Below is a picture of Everman Cove filling with brash ice taken on the same day. In late July and August there are often Leps popping up here and in the other bays.
Most of the fur seals have now left though there are still enough around to keep Don busy with the poo rounds that he does on a Wednesday. The weather has been so cold and poos so few and far between that occasionally he has had bad poo days, when the island becomes a poo desert and finding poos in the snow and chipping them from the frozen ground can be very tiresome. On other days there seem to be poos everywhere and Don barely needs to leave base to find his full quota of ten poos that will keep him busy with otolith identification for the week. This makes Don very happy. Each poo takes him around half an hour to do and he can get three or four into an afternoon if he�s on a roll. If Don is not around base or out on the lep round, you know where to find him, he�ll be in the lab doing a poo.
For me July meant the start of a new phase of work deploying GPS loggers on Wandering Albatrosses. I have been visiting the fat fluffy chicks twice daily. Some of them are now bigger than their parents, full of fish and squid and growing very quickly, spreading their fluffy wings and having a fruitless flap now and again. It's all good exercise for them, training the important muscles needed for the big day when they take off for the first time, later in the season, not to be seen again on Bird Island for at least five years. On my twice-daily rounds, occasionally I will come across a parent who has just popped in from a foraging trip of between five days and three weeks, which may have taken the bird as far as the Patagonian Shelf around the Falkland Islands and South America, in search of food for the fluff ball back home. I can then tape a small GPS logger to the adult bird�s feathers on its back that will log latitude and longitude coordinates as the bird flies on its next trip. When the bird returns, the logger is removed and from the data in the logger the flight path of the bird can be plotted, allowing us to see where in the world the albatross is travelling to catch its prey.
Above is a GPS track of a male Wandering Albatross leaving its chick in Wanderer Valley, Bird Island on 04/07/06 and returning 21/07/06, travelling a total of nearly seven thousand kilometres in seventeen days. The blue, green and white colours represent depth in meters (see scale bar). As he headed north to deep water of the Argentine Basin he crossed frontal systems where warm water of the north and cold water of the south converge. He then headed South and West towards the Patagonian Shelf, an area of shallow water around S. America and the Falkland Isles, before finally returning to Bird Island along the Scotia Ridge. Each of these marine habitats is definable by its specific ecosystem and so the prey types that are available to the Wandering Albatross. The food that it regurgitated to its chick shortly after landing on 21st would probably have been a mixture of squid and fish of all different types.
Also in July we were busy writing reports from data collected during the 2005-2006 breeding season. One of these was a report summarising debris found on Bird Island, much of which originates from fishing vessels and is brought to Bird Island by seabirds and is found in the colonies where they nest.
A longline fishery with many ships that use thousands of baited hooks anchored to the sea bed to catch Patagonian Toothfish, operates in much of the area around South Georgia, the Scotia Ridge and the Patagonian Shelf. Until recent years thousands of seabirds, including albatrosses and other threatened species, were killed annually as they were hooked and drowned on baited lines paid out from longlining vessels. The Government of South Georgia and the South Sandwich Islands and the Falkland Islands Government have now implemented strict legislation so that far fewer seabirds are killed in this way. Longlines are only set at night when seabirds are less active and lines are well weighted so that they quickly sink out of reach of birds. However, albatrosses still return to Bird Island with longline related entanglements and five birds were noted this season all with longline hooks embedded in various parts of the body and fishing line trailing. One fishing hook and line was even fed to a chick, the fishing line noticed trailing from its bill.
Female Wandering Albatross (left) and Male (right) with monofilament trailing from swallowed longline hook. This image was taken from Bird Island archives, as other images of entanglements this season were considered too upsetting for public viewing.
In addition to these entanglements, twenty-nine items of fishing gear (particularly longline hooks and line) were found in albatross colonies, mostly wandering albatross colonies, sometimes amongst squid beaks that chicks have regurgitated or in their nests. A relatively small proportion of the Black Browed and Grey Headed Albatross colonies on Bird Island are visited regularly so many fishing items and entanglements go unreported here every year.
Obviously Bird Island albatrosses are suffering losses at sea in conflict with longlining fisheries and these mortalities are contributing to the declining trend that is occurring in the breeding populations of all Bird Island albatross species. Seabird colonies on the rest of South Georgia probably suffer similarly and in areas of the world where fisheries are less stringently monitored mortalities will be higher. Bird Island birds are probably more affected during periods between breeding when they stray into distant waters where fisheries are not regulated as well as they are locally.
Donald also found more seal-fisheries interactions this winter, as entanglements have been a regular occurrence on his daily lep round. Many seals have been freed from line, nets and plastic packing bands constricting around their necks. As the seals grow these dig into the skin and strangle the seals, and they would surely die if not for Donald spotting and releasing them....what a hero!
On top of his duties as winter base commander Matt had a lot of chippie work to keep him occupied as he ploughed into his job list, which included a vanity unit in the bathroom and much needed shelving in the boot room as well as all the rat boxes. Although the new base was completed last season, there are a few finishing touches to make in the interior of the accommodation building. Matt has the vision and the skill to produce very functional furnishings in keeping with the style of the rest of the base that will last forever and will be much appreciated by Bird Islanders present and future. There are examples of Matt�s craftsmanship at bases on the Antarctic peninsula. He has been grateful for Helen�s help in much of his chippie work this winter and Helen has been enjoying the experience picking up tricks of the trade. They�re like Laurence Llewellyn Bowen and Carol Smiley of Changing Rooms....now there�s an idea! In fact Matt has shown us all a thing or two, training us with hand and power tools, do it yourself skills that we will all be grateful for when we eventually return to the UK and have houses to worry about and DIY.
At the beginning of July it was time for the midwinter photograph that we had planned for midwinter�s week, but had never got round to as it involved a large volume of water which at the time we were short of as it was all frozen and not filling the tank from the roof collection system. When the tanks were full we drained the hot water tank into the Scandinavian style hot tub and piled in for a late afternoon soak, some beer and a photo to go alongside the others in the base hall of fame that shows the succession of equally nutty Bird Island winterers from previous years.
With the temperature way below zero during much of July and no water flowing from the roof into the tank Don the water boy had to extract from a stream that flows into Freshwater Beach close to the base. The stream itself was frozen solid down to about half a meter but fresh water continued to flow below and Don was able to tap into this with a pick axe. A few teething problems with the pump motor caused water to stop flowing and freeze solid in the pipe that led it to the base tank. These were soon overcome and the tank was filled and refilled a few times with no dramas. A thaw kicked in later in the month.
Later in the month Helen, Don and I took a trip to the Loveshack, a field hut on Fairy Point at the West side of the island, where we enjoyed some real ale and fine cuisine. The hut has a kitchen area, a gas stove, an oil burner that keeps it nice and warm, two bunks and a table and benches. It makes a nice change to get out there for a night now and again. Matt stayed home, as one Bird Islander must remain on base at all times for in keeping with fire regulations. He made his own fun by turning up the heating and roaming around the base naked, playing Neil Young on his guitar and singing, he�d been talking about doing that for a while. Only kidding, I think he was glad of the peace and quiet, although the bit about playing Neil Young would be right.
Loveshack. Normally in summer Helen would have been standing in a macaroni penguin colony and (probably some poo) when she took this.
Unfortunately, Don and I are rubbish at taking photos and rarely take a camera. We figure that we�ve got another eighteen months to take pictures, but will probably panic as our time runs out and we worry that we don�t have enough shots. I think this is what has happened to Helen who is trigger happy snappy and this is why there are never enough pictures of her. Here are a few of Helen that I dug out to keep things even.
Helen is particularly sensitive to light and requires two pairs of sunglasses for her four eyes. She doesn�t miss a trick.
And here are just some random pics that I thought were pretty cool.
Gentoo Penguins, the one behind has snow on its beak and probably thinks its dead trendy.
Lots of krill washed up on the beach sent the birds into a feeding frenzy and stained the water pink. You can see the base in the background on the beach and a valley behind the base that leads up to cliffs and La Roche the mountain in the pic. After this if you keep heading north it�s the sea for a very long time until you hit the North Pole. If you look south from the jetty at this time of year there is usually an iceberg the size of a skyscraper blown in from the frozen south, such as the one below taken from the jetty looking south before daybreak. This berg below has been lodged here for nearly a month, continuously changing shape, turning and occasionally calving pieces into the sea creating a colossal crashing noise.
Above, the pink pigmented feathers of a wandering albatrosses head and below the owner of them, a male who had just landed to feed its chick. Salt is excreted from glands in the bill and it is thought that a dietary pigment in this salty excretion stains the feathers pink. The pink feathers are very prominent when the bird has recently come in from the sea where the wind has blown the feathers back and spiked them. In the picture below you can see the salt excretion dripping from the hooked end of the bill (and the same berg as in the picture above is in the background). Also interesting in this image is the damage you can see to the bill, where a fragment has been broken off, possibly a lucky escape from a longline hook but probably caused by something less sinister.
�Jamming��Or Matt showing me how its done.
Midwinter Haircuts For the Midwinter�s Photo
I took this one of Don when we were on our way down last year, waiting for the RRS James Clark Ross in the Falklands, he was writing post cards. I thought it would be a nice one for his mom back home. Sorry his hair is so short at the moment, I did try to give him a nice boy-band short back and sides look but he was having none of it so I took the guard off the shaver when he wasn�t concentrating, he wasn�t amused as you can see. And sorry to Karen and Mrs Jobson too, though Matt did ask for this specific look. Are Mohawks the fashion in Coventry? Helen also received a rather sassy bob, her re-entrance into the real world (with real boys!) is more imminent than mine and Dons so I spared her any unnecessary embarrassment.
This one just to illustrate the extent of my hair, having not cut it since last October.
And this to say thanks to my Mom for the scarf.
Towards the end of July rumours began to spread that a Naval war ship, HMS Chatham, was in the area and travelling to South Georgia from the Falklands with post and fresh fruit and veg. An exciting prospect considering that we had not seen anyone since the last ship in early April and that the last remaining eggs were laid last year. I will leave Matt to fill you in on whether this did or did not happen and all the excitement that might or might not have unfolded, when he writes the article for August.
All the best to everyone back home, who from all accounts have been sunning themselves in heatwave after heatwave.