This stamp issue, produced in association with World Wide Fund for Nature (WWF), recognizes some of the lesser-known species of seabird breeding on South Georgia. The species depicted are part of the rich biodiversity found in South Georgia’s unique environment. WWF is one of the world’s leading conservation organisations who work towards conservation and sustainability.
The cold waters around South Georgia and South Sandwich Islands are highly productive and provide rich feeding grounds for many species of seabirds. Twenty five species of seabird breed on South Georgia (with two additional species, Adélie penguin and Antarctic fulmar, breeding on the South Sandwich Islands) and many vagrant and non-breeding species are also seen around the islands.
The current human activity, primarily fishing and tourism, pose potential threats to seabirds within South Georgian waters. Tourism and fisheries are well managed in South Georgia to minimize risks to birds. Well-monitored tourist landings including restricted permitted sites and minimum distances from wildlife limits disturbance to nests sites ashore. Avian cholera is also a risk to seabirds and strict regulations on poultry products are in place including a ban on tourists taking poultry products ashore and no disposal at sea. Mandatory use of bird scaring devices and the seasonal closure of fisheries during peak bird breeding times both act to minimize interactions at sea with fishing vessels and hence protect seabirds from fishing mortality.
A historical but ongoing threat to the smaller species of seabird, and the endemic South Georgia pipit, breeding on South Georgia is predation by the introduced brown rat. Plans are in place to eradicate rats from South Georgia, which will be hugely beneficial to these species.
Imperial shag (Phalacrocorax atriceps) (60p) approx. 7,500 pairs
The imperial shag is found in rocky coastal areas and breeds in small colonies in most parts of South Georgia. They are a monogamous species and usually lay 2 -3 eggs (though can lay up to 5). Laying occurs in October/November with eggs taking 5 weeks to hatch and fledging occurring in March. Their nests are made of seaweed and grass glued together with mud and guano. Imperial shags forage mainly in inshore areas (though can also travel further offshore) on small fish, crustaceans, polychaetes, gastropods and octopuses. They dive down to an average of 28m for around 5 minutes to catch their prey, although they have been recorded to dive as deep as 70m.
Antarctic tern (Sterna vittata) (70p) approx. 10,000 pairs
Distributed throughout the Southern Ocean and common throughout the year around South Georgia, the Antarctic tern start breeding from mid-November to early December with chicks fledging in January. Nesting close to shore in natural depressions in the rock or shallow scrapes in the ground, their eggs and chicks are well camouflaged. These small birds (31-38cm long) are susceptible to human disturbance and to predation of their eggs and chicks by rats, however they will defend their nest sites vigorously, dive-bombing anything passing too close. Feeding in inshore waters, often in the kelp zone, their main prey is small fish but they also take crustaceans, polychaetes, molluscs, insects and algae.
Southern skua (Catharacta antarctica) (95p) approx. 2,000 pairs
The southern skua is a sub-Antarctic species and is regarded as having a stable population. They are distributed widely around South Georgia but are commonest on offshore islands where there are the greatest numbers of small burrowing petrels. Their hooked beak and webbed feet with sharp claws allow the skua to be a highly predatory bird, which, besides burrowing petrels, feed on penguin chicks and eggs. They will also scavenge on carrion on land as well as around fishing vessels. During the winter, skuas migrate northward, departing in April and returning to South Georgia in September. Egg laying starts in November with chicks fledging in late February.
Kelp gull (Larus dominicanus) (£1.15p) approx. 2,000 pairs
Kelp gulls are omnivores with their diet depending on food availability. They take and scavenge on small prey including molluscs, fish, crustaceans, other seabirds and even chicks and eggs of their own species. This coastal gull is common throughout the year around South Georgia and inhabits sheltered bays. They build nests lined with vegetation and feathers which are little more than a shallow depression in the ground. Two or three eggs are laid during November to December and both parents raise the chicks. Fledging takes 45-61 days and the young gulls take 3-4 years to reach maturity.
Species information from BirdLife International species factsheets www.birdlife.org
In addition to the set, there is a Souvenir Sheet showing a Juvenile Southern skua (£3.50p) and a sheetlet of 16 (4 sets in staggered format) with face value of £13.20p. The stamps in the sheetlet ‘bleed off’ at the edge.Technical details:Artist Andrew RobinsonPrinter BDT International Process Stochastic Lithography Perforation 14 per 2cmsStamp size 28.45 x 42.58mmSheet Layout 50 (2 x 25)Sheetlet layout 16 (4x4)Sheetlet size 200 x 187mmSouvenir Sheet size 94 x 64mm Release date 10 March 2012Production Co-ordination Creative Direction (Worldwide) Ltd