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Distribution of badger setts in a high-density area
Journal
Oikos, Volume
106,Number 2, August 2004, pp. 295-307(13) Publisher: Blackwell Publishing
Authors
D. W. Macdonald; C. Newman; J. Dean; C. D. Buesching; P. J. Johnson
Abstract
Are setts significant determinants of badger
socio-spatial organisation, and do suitable sett sites represent a limited
resource, potentially affecting badger distributions? The factors determining
diurnal resting den, or sett, location and selection by Eurasian badgers
Meles meles L. were investigated in Wytham Woods, Oxfordshire. 279 sett
sites were located. The habitat parameters that were associated with the siting
of these setts were analysed and associations were sought between sett location
and character and the body condition and body weight of resident badgers Habitat
characteristics in the vicinity of setts were significantly different from
randomly selected points. Badgers preferentially selected sites with sandy,
well-drained soils, situated on NW-facing, convex and moderately inclined slopes
at moderate altitude. There was no evidence that sett morphology (number of
entrances, sett area, number of hinterland latrines) was affected by the
surrounding sett site habitat characteristics. Mean body weight was
significantly higher for badgers occupying territories with setts in sandy
soils, situated on NW-facing slopes, than in territories with less optimal sett
characteristics. Contrary to the hypothesis that the availability of sett sites
was limiting, and therefore that sett dispersion dictates the spatial and social
organisation of their populations, the badgers were clearly able to excavate new
setts. On our measures, these new setts were not inferior to old established
ones, despite occupying subsequently exploited sites; the badgers utilising
these new setts had neither lighter body weights nor poorer body condition
scores. During the period of our study badgers have manifestly been able to dig
numerous new setts; as satisfactory sites still remain available, this indicates
that suitable sett sites have not yet become a limiting resource. There was no
relationship between sett age and the characteristics of the site in which it
was dug, as suitable sites were not limiting. Significantly, population
expansion during the decade 1987–1997 was not constrained by lack of setts,
rather the main proliferation in setts occurred after the population size had
peaked in 1996. Some implications for the management and conservation of the
Eurasian badger are considered.
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