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Faeces of Myotis capaccinii were collected from four individuals netted in a spring colony in Denia, Alicante (south-eastern Iberian Peninsula). Faecal analysis revealed the presence of fish scales and bones in all droppings examined (two pellets for each individual, i.e., n = 8), with volumes ranging 6-82.5 % of prey remains. Remains of Diptera and Trichoptera were also found. These data provide the first evidence of piscivory in M. capaccinii, and reveal that this may be an important feeding behaviour in this species, at least locally and/or seasonally.
In a previous study on habitat use by Rhinolophus euryale in an Atlantic area (Northern Iberian Peninsula), this bat species foraged exclusively in woodland, including both native deciduous woodland and exotic plantations. As the study was carried out in a landscape that was profoundly altered by industrial forestry, we predicted that in a better preserved landscape this species would select smaller feeding areas located at closer distances from the roost, according to the optimal foraging theory, and would use almost exclusively the preferred habitat, i.e., native deciduous woodland. To test these hypotheses, we radiotracked 14 R. euryale from the largest known breeding colony of northern Iberian Peninsula and determined their habitat selection, spatial foraging pattern, and hunting behaviour. Our predictions on habitat selection, as well as on the foraging site size and on commuting range were confirmed. Rhinolophus euryale used almost exclusively native deciduous woodland, and hedgerows were positively selected. We suggest that the richness of tree species in hedgerows provides a high prey availability sustained in time and space. Our findings show that habitat disturbance constitutes a major cause of decline for R. euryale in the study area.
We investigated the foraging behaviour of the Mediterranean horseshoe bat (Rhinolophus euryale) in an Atlantic mosaic-like landscape consisting predominantly of meadows and broadleaved tree structures, and containing the largest known breeding colony in northern Iberian Peninsula. We radio-tracked a total of 46 individuals during pre-breeding, lactation and post-lactation periods. Bats were divided into different classes based on season, sex, reproductive condition or age. Significant differences between classes were apparent in the distances travelled to foraging areas. During pre-breeding foraging occurred on average within 1.3 km, and at most 4.2 km from the roost. Contrary to our predictions, lactating females extended mean foraging distances to 4.3 km, and covered the widest range with a maximum individual distance from the roost of 9.2 km. Males in the same period foraged closer (mean 1.9 km), but with lower fidelity to the main roost. The foraging distances of adult bats during post-lactation did not differ from that of lactating females (mean 4.6 km). Newly volant juveniles flew on average 2.6 km, though showed a varied behaviour. No seasonal effect was found on the size of individual foraging home ranges, as great variation was recorded within all groups. We conclude that the increase in foraging distances is the consequence of higher density as colony size increased by 55% from pre-breeding into the lactation period on. Our results show another aspect of the scale of foraging movements of R. euryale and highlight the need to take these into account when formulating conservation policy, especially during such crucial periods as lactation and juvenile dispersal.
In July 2002, several bats of the genus Plecotus (Geoffroy, 1818) were captured at two localities of ‘Ordesa y Monte Perdido’ National Park (Central Pyrenees, Spain). They showed external characters that appeared intermediate between those of P. auritus and P. austriacus. Morphometric and genetic analysis have revealed that these long-eared bats should be ascribed to the recently recognized species P. macrobullaris. This study extends the distribution of this new species, whose western limit was considered, until now, to lie in the Alps, and adds a new mammal species to the Iberian fauna.
The trophic ecology of Kuhl's pipistrelle Pipistrellus kuhlii (Kuhl, 1817) was in­vestigated monthly from May to October 1999. Nine insect and two arachnid orders were identified in faeces and classified in 24 different categories. The most frequently occurring prey categories were Culicidae, Lepidoptera, Chironomidae/Ceratopogonidae, Hymenoptera, unidentified Brachycera, Tipulidae and unidentified Coleoptera in de­creasing order. Other categories exhibited seasonal importance, such as the coleopteran Rhizotrogus sp. Prey availability was evaluated monthly using Malaise traps in known feeding areas. Bats preyed selectively through a temporarily changing pattern. Some taxa constituted an important part of the diet and were positively selected either monthly or in most of the months. Many of them were the largest prey featuring in the diet and changes of their relative profitability across time would determine their selec­tion index. The small size of some prey categories as well as P.kuhlii's morphofunctional constraints relative to flight and echolocation could explain their underexploitation or rejection. Our results suggest that P. kuhlii could be regarded as a 'selective op­portunist' species.
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