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Owl Diet (owl + diet)
Selected AbstractsChanges in the food of British Barn Owls (Tyto alba) between 1974 and 1997MAMMAL REVIEW, Issue 2 2000R. Alasdair Love ABSTRACT Comparison of the results of a 1993,97 Barn Owl Tyto alba pellet survey with those of a similar survey from 1956,74 showed that Barn Owl diet had changed significantly. The primary differences were a widespread decrease in the percentage of Common Shrew Sorex araneus, combined with an increase in Pygmy Shrew Sorex minutus. The percentage of Wood and Yellow-necked mice Apodemus sylvaticus and A. flavicollis and Bank Vole Clethrionomys glareolus in the diet also increased. Changes in Barn Owl diet since 1974 were independent of land-class group, but were dependent upon region. This was due primarily to a large increase in the percentage of Apodemus spp. in Eastern England. Whilst the percentage of Pygmy Shrew in Barn Owl diet showed significant regional variation, there was no significant variation between land-class groups. The diversity of Barn Owl diet increased between 1974 and 1997, although it was still lower in 1997 than earlier in the century. This increase was dependent upon region, but independent of land-class group. The combined results of both surveys showed significant interland-class group variation in dietary diversity. Changes in diet are discussed in relation to the intensification of agriculture and other changes in land management since the 1970s. The effects on Barn Owls of these changes in prey abundance are discussed, particularly in relation to the decline in Barn Owl numbers during the twentieth century. [source] Impacts of Agriculture on the Diet and Productivity of Mackinder's Eagle Owls (Bubo capensis mackinderi ) in KenyaBIOTROPICA, Issue 4 2009Darcy L. Ogada ABSTRACT Land conversion for agriculture is an increasing threat to biodiversity conservation, but its ecological effects on African birds is practically unknown. We investigated the impacts of agriculture on the diet and productivity of a small, disjunct population of Mackinder's eagle owls (Bubo capensis mackinderi ) in central Kenya. Owl diet was determined by analysis of pellets and other remains and compared to small mammal populations estimated by live trapping in two habitats. Small mammal abundance was low and averaged 7.4 small mammals/ha in farms and 0.5 small mammals/ha in grassland. Owls consumed a wide diversity of prey. The majority were mammals (87%) followed by birds (7%) and insects (5%). The percentage of small mammals in owl diet correlated positively with the relative abundance of small mammals during monthly trapping sessions. Diet composition did not influence owl breeding success. Farming activities affected owl diet composition through crop production. The amount of maize, peas, and carrots growing in farms was correlated with the abundance of Mastomys sp. and Procavia sp. in the owl's diet. Agricultural activities had a large effect on Mackinder's eagle owl diet by increasing the abundance of certain small-mammal prey and attracting owl prey to farms, though farming practices harmful to owls were observed. [source] | ||||||||||