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Falklands Conservation |
From Falklands Conservation Newsletter 47, Stanley
July 2000
South American Fur Seal Study Begins
This year has seen the start of a project to study the movements and foraging behaviour of the South American Fur Seal. A survey in 1990 indicated a population of about 20,000 animals in the Falkland Islands but very little is known about their diet and nothing about their foraging habits. The Sea Mammal Research Unit have recently made three trips out to Bird Island (map) to attach satellite transmitters and data loggers and to undertake a diet analysis.
The fur seal rookery on the south east coast of Bird Island occupies an area of rock slabs and cliff ledges. Females with pups concentrate on the rock slabs, in the centre of the colony, and sub-adult males and non breeders are generally spread around the periphery, well up into the tussac grass. The rookery held an estimated 2000 pups possibly a lot more.
Satellite transmitters were fitted to 14 adult females between October last year and April this year. The results so far show that seals from Bird Island may swim up to 200km to find food, ranging as far as Beauchene Island and Burwood Bank.
Unlike the more numerous Antarctic fur seals of South Georgia, the South American species stay close to their breeding colonies throughout the year. Pups born in December and January were still suckling in November. Females were tracked during three stages of the year, when January when the pups were small, post-moult inApril when the pups are still relatively small, and pre-breeding in October when pups were large but females were heavily pregnant.
The early results show that there was a major shift in foraging behaviour. When pups were young the females made only short trips, lasting less than a day. All 10 tagged seals stayed close to the Island, rarely going more than 15km. From late February trips became long. Severals seals foraged along the south coast of West Falkland, mainly near Beaver Island, and other made longer trips out to sea to the South. In April, when their pups were larger, seals made repeated feeding trips to Beaver, 50km from Bird Island. Last October, when their pups were large, seals made a series of long trips to the south, 100-200km from Bird Island, staying away for up to 7 days.
In addition to the local fur seal population, a small female Antarctic fur seal stayed at the rookery for at least a week in February, and an adult female sub-antarctic fur eal and her pup were present from January to April.
Recent Falkland Bird Records
Thanks to Alan Henry for drawing up this list.
Bairds Sandpiper (Calidris bairdii) - up to four birds seen around Cape Pembroke through December and January, and 2 sighted on Pebble Islands on 23 January.
Great Grebe (Podiceps major) - a pair were spotted on Pebble Island between 18 and 23 January and may have been there longer.
White Winged Coot (Fulica laucoptera) - one bird resident on Pebble island for at least the period 18 to 29 January.
Arctic Skua (Stercorarius paraiticus) - one bird seen on Saunders Island on 26 January and again on Pebble Island on 12 February.
Pectoral Sandpiper (Calidrid melanotos) - 1 seen on 23, 2 on 27 and 4 on 29 January on Pebble Island.
Rosy-billed Pochard (Netta peposaco) - one male bird was seen on Pebble Islands between 27 January and 12 February. This same bird was sighted on Saunders Island in December 1999.
Red Gartered Coot (Fulica armillata) - one bird was sighted in the York Bay area between 3 and 10 June and again on 1 July. Most likely to be the same bird, it was again seen at Surf Bay on 6 July and at Moody Brook on 16 July.
Great White Egret (Egretta alba) - one sighted at Estancia on 11 February and again on Weddell Island on 13 February, possibly the same bird.
Cocoi Heron (Ardea cocoi) - one immature bird was resident at Teal Inlet for at least the period 13 May to 4 July.
American Purple Gallinule (Prophyrula martinica) - for the second winter running one dea bird was found at Teal Inlet. This year's specimen was found on 4 July and was still very fresh.
Coscoroba Swan (Coscoroba coscoroba) - between 2 and 8 are resident on Pebble Island.
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Patron: HRH The Duke of York CVO ADC Member of the International Union for Conservation of Nature | BirdLife International Representative |