Department of Statistical Sciences
University of Cape Town
| Avian Demography Unit
Department of Statistical Sciences University of Cape Town |
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Earthwatch Project: South African PenguinsDiary of Team One
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Photo L. Underhill
Mario Leshoro is the Environmental Officer, Robben Island Museum |
A quick trip from Murray's Bay Harbour took Team One to the Marine and Coastal Management house, a few minutes walk from the Robben Island Lighthouse, which was still blaring its foghorn into the mist at regular intervals. First impressions were that the house was larger and more comfortable than anticipated. Leshia Upfold, one of the staff at Marine and Coastal Management had recently turned the house into a home, with curtains, plus sheets and duvets, whereas we had been expecting to sleep in sleeping bags. Thanks, Leshia.
Mario Leshoro, Environmental Officer for the Robben Island Museum, took us on an orientation drive around the island. The chief hazard here, somewhat unexpectedly, is the ostrich; when they have eggs or chicks to defend, they do not need to be provoked to come running at you.
After lunch we set off into the penguin colony for our first stint of fieldwork. Cape Town had just experienced a late-summer heatwave. One of the consequence of this was that a lot of the early-nesting penguins had deserted their nests in the fortnight prior to our arrival, leaving their eggs to the marauding Kelp Gulls. The impact on us was that there were far fewer penguin nests than anticipated at this time of year.
Photo L. Underhill
Ann Geoghegan doing data entry |
Our project design requires us to find 50 where both adults are not already flipper-banded. Because thousands of penguins were flipper-banded after the Treasure oil spill of June 2000, finding these 50&nests:was going to be difficult in any event, and the mass desertions compounded the problem.
In spite of this we found several nests with an unbanded adult sitting either on eggs or with tiny chicks. These couldn't get the new-design plastic bands immediately, because we had to wait for a nest changeover to be certain that the other adult was also unbanded. The unbanded parent on the nest was marked with a few dots of picric, a brilliant yellow plumage dye, so that it would be easy to check when the changeover had taken place. We found one nest with both adults banded; one of these had been banded as an adult in 1986, so this bird would have been at least 18 years old.
Saturday, 3 March 2001: We are in the field soon after 0800. Half of Team One checked nests for naked parents, giving those they found somewhat punk featherdos. Altogether we checked 23 nests during the course of the morning. The other half of the team, armed with telescope, checked penguins on their landing beaches for flipper bands. This is crucial follow up work to the Treasure oil spill. A hot muggy sun drove us home by midday.
Photo L. Underhill
The Marine and Coastal Management house on Robben Island where the Earthwatch teams stay. This house has the best view in the village. The church was built by the navy 100 years ago. The hill on the mainland is called Blaawberg, where a battle was fought when the British took the Cape from the Dutch in 1806. |
At around 1530 we set off in two groups to do a round-island count of shorebirds - waders, gulls, terns, cormorants, egrets, etc. We discovered that it is a long way around the island on foot!
Best bird sightings of the day were a Peregrine Falcon stooping on pigeon, Blackcrowned Night Heron roosting in the forest, Greenshank on the shore, thousands of Sabine's Gulls offshore (many in juvenile plumage), even a Barn Swallow at van Riebeeck's Quarry, and believe it or not, our first Cape White-eye, a species described as "common breeder". The bird list for the day totalled 43 species.
Sunday, 4 March 2001: Once again, we were in the field at 0800. Eight of the nests were we had left punk penguins yesterday had had changeovers of parents during the night, and the parent on the nest was also naked. These eight birds were fitted with the new "Barham Bristol Bands". Next time there is parents swap incubation duties, the mates will get the new bands as well. At one nest, both the punk parent and the plain parent were present, so both got the new bands. This means that we have deployed nine of the 50 bands, and need another 17 nests with both parents naked. Once again, the heat drove us homewards around noon.
The telescope team resighted 114 flipper bands today.
We made the discovery that substantial numbers of penguins are taking the short cut to their nests across the beach to the south of the harbour. This is good news, because many penguins have been stubbornly following a traditional route, walking at least one kilometre, and crossing several busy roads, to reach nests which are, in fact, less than 100 from the sea.The daily bird list was a bit shorter, at 36 species. The new species added to the list during the day were Pied Crow and Whiterumped Swift. After dark, the Fierynecked Nightjar was heard calling.
Photo Les Underhill
Close-up of a rubber band |
Monday, 5 March 2001:After an emailing session in Mario's office, we made a later-than-usual start. One team worked the nests along Cornelia Road, and the other did band resightings along the shoreline. We found a nest with both parents banded; the band numbers indicated that both were oiled in the spill last year, and had been cleaned at SANCCOB. It got hot early, and we headed homewards by noon.
Straight after lunch, the Earthwatch team members joined the island visitors on a tour of the prison. Their guide was Patrick, a man who spent 20 years in the prison. He was incarcerated at age 19, spending most of his youth on Robben Island. Patrick's very moving presentation stressed the process of forgiveness and reconciliation.
The rest of the afternoon was spent sorting out the paperwork, and getting the resightings into a spreadsheet. In the evening, we had a barbecue, with kebabs, boerewors (=sausage), potatoes, butternut, onions and carrots all cooked on the fire.
Tuesday, 6 March 2001: The morning was the normal drill, out in the colony checking nests in an assortment of ways. As the number of nests grows, it gets trickier to relocate individual nests. But the GPS is an invaluable aid to our navigation; with the "random error" now removed, readings on a nest seldom differ on subsequent days by more than 3/1000s of minute (about 5 metres) from the original reading. All the same, we need to devise a simple and robust nest marking system, at the nest sites themselves.
Most of us had a snooze after lunch. In the late afternoon, we counted the penguins that came ashore across the beach south of the harbour. These are the birds taking the sensible short-cut to their nests, rather than going the long way round. Peak count on the beach was close to dusk, at 91 birds, by which time about another twenty had walked up the beach to their nests.
New species for today included three Egyptian Geese, seen from Cornelia Road flying over the "forest", and several Alpine Swifts were seen feeding on the wing over the village.
Photo Les Underhill
Penguins crossing the beach south of Murrays Bay Harbour |
Wednesday, 7 March 2001, Day off: Principal Investigator Les slipped out of the MCM house at 0615, in the half dark. During the 20 minute walk to the ferry he saw three male fallow deer, with impressive antlers, and one cat. Les caught the 0645 staff ferry, watched the sunrise over Table Bay, and spent the day in and out of his office at UCT.
The rest of the team followed on the 0815 staff ferry, arrived in Cape Town 30 minutes later, Pat, Sue and Anne took a taxi to the Lower Cableway Station, and were on the top of Table Mountain by 0930. Pat was amazed at the speed of ascent, the design of the cable car, and that its floor did a 360-degree rotation on the way up, so everyone could see in every direction. From the top, they rated the views breathtaking; they could see Cape Point in one direction, and Robben Island in the opposite.
Birds on Table Mountain included abundant Cape Siskins and Orange-breasted Sunbirds. Well trained tourists fed the Rock Hyraxes, locally known as Dassies. The mountain fynbos at the top also impressed the group, who spent nearly two hours at the top before heading down to the Waterfront for lunch and an afternoon's shopping.
Photo Les Underhill
This time it is a safe passage across the road to the harbour. If only they knew that the sea could be reached within 50 m without crossing this road! Instead, following this traditional route they still have about 300 m to march |
Meanwhile, Jim had a leisurely breakfast in the Mugg and Bean, at the Waterfront where the ferry docks, and then set out for Kloof Nek and climbed to the top of Lion's Head (669 metres, 2195 feet). He describes it as a good work out, with steep scrambling over rocks near the top. The view from the top is panaramic, and made the climb worthwhile. He walked back down to Kloof Nek, and walked back down to the Waterfront. It is a long, long way. So he revisited the Mugg and Bean (long stay), and came home later than the rest of the team on the 1800 ferry.
The rest of the team met up at the Waterfront, and took the 1645 staff ferry back to Robben Island. Kathy Calf, a student about to start her PhD at UCT, joined us for the night.
Thursday, 8 March 2001: Refreshed from our day off, we were ready to roll at 0730, and worked in the penguin colony until nearly 1330. The number of nests under surveillance has grown to close on 80, and we are still looking for nests with both birds unbanded. We currently have 15 &of these nests, and need at least another ten. But the number of nests at which we have been able to catch both adults to rubber band them is five! Kathy's assistance was invaluable; she left for Cape Town on the 1600 staff ferry.
The new telescope was put into service today, and Pat and Anne worked independently along the entire shoreline north of the harbour. Late in the afternoon, they visited the beach south of the harbour and read another 22 flipper bands in this section. The file of band resightings has grown to 684 records.
Supper tonight was baked hake (=local deepwater fish), ratatouille, hash browns, salad and fruit salad. Paperwork and data entry were more or less brought up to date.
Photo Les Underhill
A springbok walks out of the front gate of the MCM house on the island |
Friday, 9 March 2001: We set to work diligently today on getting the nests properly marked. The nests along the shoreline were completed by lunch time. Two male Ostriches, accompanied by two females, gave us a few anxious moments, but it seemed that their approach to within 50 m was driven by curiosity rather than a desire to see us out of their territory. In the afternoon, we completed marking the nests between the southern end of Cornelia Road and the shoreline.
UCT student Fikile Hlatshwayo arrived on the 1645 staff boat for the weekend; she is doing BCom(Hons) in Statistical Sciences. In spite of her commerce background, her honours project is going to involve a statistical analysis of certain aspects of the data being collected by the Earthwatch project. For example, from the measurements and mass of a penguin egg, Fikile will develop a technique for estimating when it was laid (to grasp that this is possible, you need to know that eggs lose weight during incubation, and that the calculations depend on calibrating the rate of loss of mass).
The evening meal was our third braai, which was followed by data entry. The number of flipper bands read in the past week is approaching one thousand.
Photo Les Underhill
The Earthwatch team, plus a few visitors, having lunch |
Saturday, 10 March 2001: Anne and Pat used the two telescopes to read band numbers on the shore, and came back for lunch satisfied with the morning's work. Anne was first to see a bird with a rubber flipper band on the shore. She said it was MUCH easier to read than the steel bands. We also resighted the penguin with stainless steel flipper band S20663. This penguin was oiled and cleaned in the Apollo Sea spill of 1994; it was oiled again in the Treasure spill of 2000, and there is a picture, taken on 25 June 2000, of this penguin smothered in oil on the ADU website. It is good to know that it has once again made it through the cleaning process, and that it is alive and well on Robben Island.
Mario and Jenny Griffin joined Fikile, Sue, Jim and Les doing the morning nest round. We marked the remaining nests on Cornelia Road with plastic nest tags. After a while we split into two groups; Jenny's MSc project involves finding nests at which at least one of the adults was ringed as a chick, in order to get a handle on how breeding success varies with age.
Jim and Anne counted about 70 penguins coming ashore by dusk on the beach south of the harbour. Jim witnessed a fur seal tossing what looked like a fish about less than 100 m from the shore, while Kelp Gulls circled overhead. Seals just offshore would almost certainly inhibit penguins from coming onto the beach.
Pat, Les, Sue, Anne, Jim and Phil on the jetty on Murrays Bay Harbour
on departure day
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Sunday, 11 March 2001: In the morning, Mario and Jenny joined Sue, Jim and Les searching for nests in a previously unexplored area close to the penguin hide. 20 nests were found and marked. We had our first cool afternoon, with a bit of cloud, and did the nest monitoring along Cornelia Road without discomfort. An after supper count showed that we have found nine nests with both adults marked with the new rubber bands, and 18 nests with both marked with stainless steel bands. The target is 25 of each type.
We now have several nests in which both adults are survivors of the Treasure oil spill. There is one nest in which one adult is a survivor of the Apollo Sea spill of 1994, and the other is a survivor of last year's Treasure spill.
Monday, 12 March 2001: Today was media day, with Kobus Lourens, Environmental Reporter from Cape Town's morning Afrikaans newspaper, Die Burger and Gerhard van Niekerk of e-TV. They took notes and visuals of the project.
Team One met Dr Rob Crawford, PI for the Team Four, who is fisheries biologist with a particular interest in seabirds, working for Marine and Coastal Management (MCM), which is part of South Africa's Department of Environmental Affairs and Tourism. Phil Whittington, PI for Team Two, joined Team One for their last few days, catching up on what we had done, so the transition to Team Two, will be seamless. Bruce Dyer, one of Rob's assistants, did the fortnightly MCM monitoring of penguin nests, so we had the largest group, nine, sitting round the table at lunch time.
Les and Fikile measure a penguin egg. Fikile's honours project in
Statistics involves estimating the laying date of eggs
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Tuesday, 13 March 2001: Last day of field work. After a cool start, the day warmed up rapidly, and we were all happy to get out of the sun at lunch time. We wrapped up all the paperwork in the course of the afternoon and evening, and team members went off to do the things they wanted to in the afternoon. Sue to the curio shop at the harbour, Jim to explore the 12 guns in the World War II battery, Anne rode an MCM bicycle all the way round the island's perimeter road, turning every stick into an ostrich neck, and Pat went back to the beach so that we could be certain that the file of the number of resightings contained at least 2000 records. Phil was also doing resightings, and the resightings file ended up at 2150 records of 1450 different penguins. We made the MCM house "Swiss-clean".
Shaun Davies, who both works and lives on Robben Island, joined us for a braai (=barbecue) in the evening. Shaun is PI for Team Five.
Photo Les UnderhillA stainless steel flipper band |
Wednesday, 14 March 2001: After an early breakfast, Shaun took Team One to Murrays Bay Harbour, where they left on the 0815 staff ferry for the mainland. Mario, Les, Phil and Shaun were on the jetty for the last photos and to wave good-bye. Team One has got the rubber-band testing project off to an excellent start. Provided someone on Team Two can be persuaded to do a diary for their team, this saga will continue next week.
The Earthwatch penguins were on the e-TV news this evening.
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Fitting a rubber band 
Photos Earthwatch |
