This week Islay Seasonwatch focuses on the Pale or Light Bellied Brent (Branta bernicla hrota) Geese which are rare winter passage migrants to Islay. Only small numbers of these geese maybe seen around Loch Indaal and Loch Gruinart feeding on the shorelines.
Population and Distribution: The pale bellied brent breeds on both sides of the Atlantic in three separate ranges. One breeds in Svalbard and overwinters in Denmark and north east England. The other breeding areas are north and east Greenland and on northern arctic Canadian islands. The Canadian breeders migrate to Ireland for winter and stop on Islay on passage to their overwintering grounds. The main influx is around mid October. They return north again in early April and many birds stop in Iceland on their way north, continuing to reach their breeding grounds in the arctic by early June. The Pale Bellied Brent Goose is an internationally important Species of Conservation Concern listed as amber.
Information on the Pale Bellied Brent and its conservation and population status is provided by the Wildfowl and Wetlands Trust. Current monitoring of this population is undertaken by the Irish Brent Research Group whose website provides some really interesting research on tracking and monitoring of these geese together with the Wildfowl and Wetlands Trust.
Migration and breeding: The Brent geese pair for life. In the Canadian Arctic they nest within 10km of the coast. They mainly nest colonially close to water in small groups on coastal islets or small islands within inland lakes. The nest comprises of a shallow depression on a dry hummock lined with grasses and mosses. Old nests are reused and relined with mosses each year. The Brent has the longest migration of all geese so the breeding season is short. Incubation takes 26 days. The young leave the nest within two days and feed themselves and fledge at around 40 days. They remain with their parents through the first autumn and winter and start the spring migration together but disperse before they return to their breeding grounds. Continue reading.....Behaviour: The Brent Geese feed mostly on vegetation but molluscs, crustaceans and lugworms are taken. A wide variety of plants are grazed or torn or pulled up underwater or when drifting. Plants covered by the tide are taken by up ending or swimming with the head and neck below the water. At low tide rhizomes are exposed or loosened from mud by grubbing and trampling. In the breeding grounds of the arctic food includes algae, mosses, lichens and the stalks of grasses and herbs. Winter feeding is on mudflats where it favours eel-grass and cultivated fields of winter cereals and oil seed rape.
Pale Bellied Brent Geese at Loch Gruinart
Identification: Pale Bellied Brent Geese are a stocky duck-sized goose which has an all black head. Both male and female are similar with no seasonal variation in plumage. The Brent Goose is highly gregarious in autumn and winter when it flocks often in hundreds wheeling rapidly back and forth between foreshore and inland feeding grounds and roosts. They rarely fly in a V formation but can be seen in lines of undulating waves flying much faster with quicker wing beats than other geese. They have a distinct rolling rronk call.
If you are in the Bridgend area of Loch Indaal or around Loch Gruinart there is a chance you could see small numbers of these geese on the shorelines or mudflats.... keep your eyes open and you may be lucky enough to spot them. As always enjoy your goose watching!
Teresa Morris, Islay Wildscapes