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The territory mapping technique censuses of the Collared Flycatcher F. albicollis were conducted on 25.5 ha plot in the Białowieża National Park. Conducted at the same time within the same plot, an intensive study on the ecology of the Collared Flycatcher allowed us to precisely assess the true number of breeding pairs (all nests were found). The combined version of mapping technique yields numbers which are an average 67% (min. 54, max. 92%) of the true numbers of the F. albicollis breeding pairs. This underestimation is negatively related both to the breeding losses in the Collared Flycatcher (r = -0.87, p = 0.010) and to its breeding density (r = -0.64, p = 0.125). Despite this underestimation the year-to-year changes in numbers obtained by both methods are positively correlated and highly significant (r = 0.84, p = 0.017). After an arithmetical formula was applied (i.e. 1.82 * mapping result - 7.33) only an average 14% of bias occurred.
We studied the fluctuation in 1975-1997 numbers of two species: the Pied Flycatcher Ficedula hypoleuca and the Collared Flycatcher F. albicollis breeding in natural cavities in the primeval deciduous stands of the Białowieża National Park (NE Poland). Both studied birds are commonly regarded as competitors if sympatric. Densities of two flycatchers are positively correlated within 7 plots (pooled data) investigated by a territory mapping method over 22 years (r = 0.71, p < 0.05) and 36 ha plot studied very intensively through 9 years (r = 0.35, p < 0.05). We found no evidence that the Pied Flycatcher density is negatively affected by the dominant Collared Flycatcher when that stronger species has a higher density. Clearly, both species fluctuated in a parallel way which contradicts an earlier generalization. The Pied Flycatcher breeds in Białowieża deciduous stands in much lower densities than the Collared Flycatcher does.
The presence and diversity of wild bird remains recovered from archaeological sites can be used to explore questions beyond mere subsistence strategies and wildfowling techniques. A survey of 26 avian assemblages from English Anglo-Saxon vertebrate assemblages (broadly classified into settlement types) was undertaken in order to assess if interpretable patterns of data, reflecting attributes linked to the broader nature and character of settlements and their inhabitants, could be recovered. A more limited range of species were noted from ecclesiastical rural and early trading emporia (wics) compared with the high status estate and urban centres. A case study (using data from the well stratified assemblage from Flixborough, UK), supported broad conclusions drawn from the original survey by highlighting a possible ecclesiastical avian ‘signature’ at this site during the 9th century, with elements associated with high status identified from the 8th and 10th centuries. Further, more detailed, consideration of individual avian species (particularly Gruidae, Ardeidae and raptors) also suggest their association with particular categories of sites and their significance in identifying high status pursuits such as falconry.
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