Anthony D. Fox

Seasonal variation in weight, body measurements and condition of free-living Teal

The weights and measurements of almost 7000 Teal captured in Abberton Reservoir, Essex during 1969–85 were analysed. Teal showed significant differences between the first year and adult birds and between males and females in tarsus and wing length, but significant differences only between the sexes in skull length. Weights were corrected for body size using wing length to give a condition index. The index of condition increased in all age and sex classes from September to reach maximum values late in the year, before falling to lowest levels in February. Female birds show more marked responses by the reduction in January condition index to hard weather than males and, indeed, the proportion of females caught at Abberton significantly declines with increasing severity of weather conditions. The significance of these sex related responses are discussed in the light of known features of the ecology of the species.

Winter movements and site-fidelity of Pink-footed Geese Anser brachyrhynchus ringed in Britain, with particular emphasis on those marked in Lancashire

Census data show that the distribution of Pink footed Geese Anser brachyrhynchus in different parts of their winter range in Britain changes within seasons. Large numbers arrive during October and November in Grampian Region, east-central Scotland, Borders Region, Lothian Region and Lancashire. Numbers peak in England during mid-winter, with few persisting into March, by which time the more sedentary winter populations of south-west Scotland and throughout eastern Scotland have begun to be augmented, presumably through arrivals from further south. Maximum numbers occur in northern Grampian and the Moray Firth from March onwards and peak during April. Individually marked Pink footed Geese captured in Lancashire dispersed to the Ribble Estuary, the south Lancashire Mosses and elsewhere in north-west England. Part of this population moves on to spend mid-winter in Norfolk. In January, there is a conspicuous migration northwards in Britain, with individuals travelling through Fylde, the Solway and east-centra...

The Greenland white-fronted goose Anser albifrons flavirostris in Ireland and Britain 1982/83–1994/95: Population change under conservation legislation

After protection from hunting on the wintering range in 1982/83, complete surveys of Greenland white-fronted geese at all known Irish and British wintering resorts have been carried out annually. These showed that this population increased by 5.0% per annum from 16,541 in spring 1983 to 30,459 in spring 1995, characterised by a 6.6% annual increase during 1982/83–1991/92, followed by a less rapid increase in subsequent years. In addition, regular counts of at least eight wintering flocks also exist prior to 1982/83. Five of these (including the two most important, Islay in Scotland and Wexford in Ireland) showed no trend before protection, but significant increases after legislation. Two other flocks at protected sites showed increasing numbers prior to changes in legislation, followed by stable numbers afterwards and the eighth flock increased in number before and after protection. On Islay, a significant increase in crude adult annual survival rate (based on census data) occurred after the hunting ban. Numbers on Islay continue to show linear increase. At Wexford, there was no significant difference between crude adult survival before and after the hunting ban where, after a short period of increase, numbers stabilised at 8,000–10,000 after 1990. There were no significant differences in the proportions of young birds before and after protection in these two flocks. Despite overall population increase, seven flocks have become extinct during 1982–1995 and a further five are close to extinction. Eighteen flocks have declined since protection, 35 showed no significant trends and 20 showed increases. Multivariate analysis suggests size, number and quality of feeding areas, levels of disturbance, flock size and latitude influence flock status - smallest most southerly flocks on fewest, poor quality limited feeding ranges showing most serious declines. The consequences of increasing concentration of the population at a few wintering areas need urgent attention and mechanisms should be sought to maintain current range, particularly on traditional semi-natural or low intensity agricultural land.

Wintering site interchange amongst Greenland White-fronted Geese Anser albifrons flavirostris captured at Wexford Slobs, Ireland

The maximum count of Greenland White-fronted Geese wintering at Wexford, south-east Ireland (where over a third of the population winters) increased from 7910 in 1984/85 to 9530 in 1989/90. Although the population tends to be highly site-loyal on the wintering grounds, 14% of 700 marked geese seen in two consecutive winters changed site. Counts elsewhere in the wintering range and the recorded movements of marked birds indicate that a large influx of geese from Scotland to Wexford occurred in 1988/89. In the previous and subsequent winters large numbers of geese from Wexford remained in Scotland. No sex-related difference in birds changing site could be detected, but 68% of known-age birds which moved did so in their second and third winters when pairing is most frequent. Only 39 marked geese were recorded moving within winters (an average of 2.8% of the population each year), virtually all of these involved geese staging on route to or from wintering sites within Britain and Ireland. The maximum numbers ...