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Satellite tracking of Greenland White-fronted geese

During 1996 - 1999 the migration strategies and staging areas in Iceland and West Greenland of the Greenland White-fronted goose were studied using small satellite transmitters. The team was headed by Alyn Walsh, Wexford Wildfowl Reserve, Dúchas/The Heritage Service, Ireland, Tony Fox, DMU (Dept. of Coastal Zone Ecology, Denmark) and Christian Glahder, DMU (Dept. of Arctic Environment, Denmark).

The Greenland White-fronted goose (Anser albifrons flavirostris) is a White-fronted goose subspecies only breeding in West Greenland between Nuuk (64°N) and Upernavik (73°N). It winters in Ireland and Scotland and migrates through Iceland and across the Greenland ice-cap in spring and autumn. It stages in Iceland for 2-4 weeks before the ongoing migration. Today the total wintering population numbers c. 30,000 birds, which is a relatively small global population. Like many other goose populations numbers have increased since 1970s. At that time the population estimate was about 14,000 birds, but especially hunting bans in Ireland and Scotland and also a change to more nutritious food during winter have more than doubled numbers.

The purpose of this satellite telemetry study was primarily to identify important spring staging areas in Greenland and Iceland. To be able to breed successfully the breeding birds must rebuild their condition on the staging areas in West Greenland after the migration across the ice-cap. Disturbances from e.g. mineral exploration can decrease the period devoted for feeding and thereby cause less successful breeding. Therefore it is important to protect the most important spring staging areas during a three weeks period in May. Also, the purpose was to study migration strategies of the Greenland White-fronted geese.

In late winter 1996 the method was tested on 12 geese caught on Wexford Slobs in southeastern Ireland. During a three months period the behaviour of the geese was studied. Two types of dummy transmitters with different weights and two harness types were tested. The following three years 21 satellite transmitters were attached to adult male geese cannon-netted in Ireland. The weight of the transmitters was about 30 grams. Twelve of the geese were tracked to Iceland and ten were tracked further to West Greenland. These geese staged on 11 different spring staging areas of which eight were new areas while three were known from previous aerial studies. The geese staged on average 11 days on the spring staging areas before they continued their migration to the breeding grounds. The majority of these areas were situated in the northern part of the breeding range and some areas were about 600 km north of the staging areas.

On average the transmitter signals were transmitted for half a year and only few of the geese were tracked back to Iceland. Many of the geese were observed in Wexford during autumn the same year and most were without the transmitter. The geese were recognised by the code on the neck-collar. These collars were attached together with the satellite transmitter.

The majority of the geese attached with a transmitter initiated their migration in tail-wind conditions. One goose made the c. 1600 km from Ireland to southwestern Iceland in just 13 hours. The average ground speed was 124 km/hour! Wind speeds and directions confirm this average ground speed. Three of the geese landed on the ice edge of the polar ice off East Greenland and staged here for seven to 30 hours. Another goose double backed halfway across the ice-cap with no obvious reason. It spent the summer on the East Coast and migrated to Iceland early autumn and was later observed in Wexford.

On the Danish link below photos and the migration route of K3F can be seen.

Photos and the migration route of K3F


Greenland White-fronted geese cannon-netted in Wexford, SE Ireland. About 8-9,000 White-fronts, or about one third of the total population winter here. The photo is taken late March. Photo: C. Glahder, DMU




This adult male Greenland White-fronted goose was fitted with a neck-collar and a satellite transmitter of c. 30 g. On 22 March 1998 it was caught in Wexford and on 18-20 April it migrated towards western Iceland. On 8 May it migrated West and arrived on 10 May at Ilulissat, Jacobshavn, in West Greenland. It stayed here at least until 20 September where transmissions stopped. On 27 October 1998 it was resighted in Wexford without the transmitter. The white triangle on the map shows its movements. Photo: C. Glahder, DMU



Migration and staging in Ireland, Iceland and Greenland of 11 White-fronted geese attached with a small satellite transmitter. The transmitters were attached during March-April 1997-1999 on the major wintering ground at Wexford, Ireland. Only three geese could be tracked back to Iceland during autumn. The last pink position on 25 October 1999 is strange, but (1) indicates a rather reliable transmission.




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Christian Glahder

01.11.2007


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