Branta canadensis – GWYDD CANADA – Breeding resident
Comparison with previous atlas:
|No of tetrads occupied||16 (of 478)||94 (of 490)|
|Percentage of tetrads||3.4%||19.2%|
Canada geese were introduced into Pembrokeshire in 1955, at Boulston, on the Western Cleddau and in 1957 at Orielton, where they continued to breed until 1977. The Boulston group became well established, with 30 geese present in 1968, 78 in 1971 and 159 in 1986. Pairs bred at Haroldston West and on Sheep Island in 1976, although at this time, the population was still generally confined to the upper Daugleddau Estuary, which they seldom left. Between the 1984-88 and 2003-07 tetrad surveys the Canada goose population underwent a significant expansion in range, as shown on the tetrad map.
The tetrad map for 2003-07 shows that as a breeding species, Canada geese are now widely spread across the county. They are opportunistic colonisers and breeding pairs have become established on farm irrigation reservoirs and large ponds with nesting islands and grazing close-by. Breeding pairs have also taken up residence on some of the small rocky islets off the mainland coast of Pembrokeshire, as well as on the islands of Skokholm and Skomer.
In 2003-07, breeding was confirmed in 52 mainland tetrads. Assuming a nesting density of at least one pair per tetrad, and taking into account the 16 pairs on the two islands, the breeding population in 2007 was at least 68 pairs, and may have been closer to 100 pairs.