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1

Evidences of piscivory by Myotis capaccinii (Bonaparte, 1837) in Southern Iberian Peninsula

100%
Aihartza J. R., Goiti U., Almenar D., Garin J.
Acta Chiropterologica
|
2003
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tom 05
|
nr 2
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.
2

Influence of habitat on the foraging behaviour of the Mediterranean horseshoe bat, Rhinolophus euryale

100%
Goiti U., Aihartza J. R., Garin I., Zabala J.
Acta Chiropterologica
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2003
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tom 05
|
nr 1
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.
3

Prey selection by Rhinolophus hipposideros (Chiroptera, Rhinolophidae) in a modified forest in Southwest Europe

100%
Lino A., Fonseca C., Goiti U., Pereira M. J. R.
Acta Chiropterologica
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2014
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tom 16
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nr 1
The knowledge of the diet of endangered species provides information on ecology and behaviour that is essential for the adequate management of their populations. Population decline may be indeed associated with diet specialization and unavailability of feeding resources, especially in modified environments. We studied the diet and prey selection of Rhinolophus hipposideros Borkhausen, 1797 in a modified Mediterranean landscape in Portugal, where this species is classified as vulnerable. Diet composition was evaluated by analyzing faecal pellets collected in a breeding colony of R. hipposideros, and the available arthropods were sampled using a light trap set outside the roost. The most consumed prey were Lepidoptera, Tipulidae (Diptera), Hymenoptera, Diptera and Neuroptera. Arthropod diversity remained fairly constant in the diet, but not in terms of prey availability. Our results show that R. hipposideros is a generalist species that feeds on a great number of prey species. However, our data suggest that, within the broad dietary niche, R. hipposideros is not opportunistic, actively selecting Diptera as a preferred food item. Despite the marked differences in foraging habitats, our results are closely match to those of studies done in Western and Central Europe, suggesting that R. hipposideros feeds on similar taxa all across Europe. However, as many studies indicate, this species selects broadleaved woodlands and riparian vegetation to forage, so conservation measures should take into account the protection of native forest and the maintenance of forest corridors among them, as R. hipposideros seems to avoid crossing open areas.
4

Seasonal foraging by Rhinolophus euryale (Rhinolophidae) in an Atlantic rural landscape in northern Iberian Peninsula

88%
Goiti U., Aihartza J. R., Almenar D., Salsamendi E., Garin I.
Acta Chiropterologica
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2006
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tom 08
|
nr 1
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.
5

Habitat selection and spatial use by the trawling bat Myotis capaccinii (Bonaparte, 1837)

88%
Almenar D., Aihartza J., Goiti U., Salsamendi E., Garin I.
Acta Chiropterologica
|
2006
|
tom 08
|
nr 1
Habitat selection and spatial use was studied in a population of Myotis capaccinii (Bonaparte, 1837) in the eastern Iberian Peninsula during the spring of 2004. The radio-tracked bats used only aquatic habitats as foraging sites, and most foraging activity concentrated on rivers. Rivers were positively selected and showed the highest preference rank. Pools were also positively selected but only a single pool was used through the tracking period. Foraging was not evenly distributed along rivers. The features of the water surface further determined habitat selection. Open waters with smooth surfaces were selected over cluttered surfaces or waters completely covered by vegetation. This microhabitat preference is thought to be due to a greater efficiency in prey detection and capture over open calm waters. Nonetheless, the extremely high aggregation of foraging individuals observed suggests that the distribution of prey might also affect the location of foraging sites along rivers. Thus, conservation management of M. capaccinii should ensure protection of low-flowing or stagnant waters in rivers around the bats' main caves.
6

Presence of Plecotus macrobullaris (Chiroptera: Vespertilionidae) in the Pyrenees

88%
Garin I., García-Mudarra J. L., Aihartza J. R., Goiti U., Juste J.
Acta Chiropterologica
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2003
|
tom 05
|
nr 2
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.
7

Fishing behaviour in the long-fingered bat Myotis capaccinii (Bonaparte, 1837): an experimental approach

88%
Aihartza J., Almenar D., Salsamendi E., Goiti U., Garin I.
Acta Chiropterologica
|
2008
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tom 10
|
nr 2
To study the fishing behaviour of Myotis capaccinii, we performed an experiment in a flight tent containing an artificial pond. We recorded the behaviour of two groups of bats — eight individuals from two different roosts — using IR video camcorders and ultrasound detectors, and evaluated diet by analyzing faeces. Nightly, increasing amounts of fish were released in the pond. Our data show that M. capaccinii is able to exhibit fishing behaviour when fish occur in high densities in shallow waters, gaffing live fish from the water using their hind feet. They were attracted neither by dead fish floating, nor by ripples made by fishes feeding on the water surface. Bats showed a specific fishing behaviour with two main foraging patterns: A) long series of circular flights, skimming along the water and dipping in softly twice or three times in each roundabout; B) long figure-eight loops with bats flying faster and higher, swooping down on the centre of the pond, where they snapped their hind feet hard into the water. Compared with the echolocation calls used to catch insects from the water's surface in the wild, terminal buzzes were incomplete during the dips made to fish. Buzz II were always lacking, and buzz I had much longer inter-pulse intervals. This suggests that they were not pursuing specific targets but dipping randomly. We propose a scenario in which fishing behaviour occurs in the wild, linked to the seasonal drought of small ponds, marshes, or channels where large numbers of small fish become readily available and thus a profitable resource.
8

Diet and prey selection in Kuhl's pipistrelle Pipistrellus kuhlii [Chiroptera: Vespertilionidae] in South-Western Europe

88%
Goiti U., Vecin P., Garin I., Salona M., Aihartza J. R.
Acta Theriologica
|
2003
|
tom 48
|
nr 4
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.
9

Habitat selection in Nathusius' pipistrelle (Pipistrellus nathusii): the importance of wetlands

76%
Flaquer C., Puig-Montserrat X., Goiti U., Vidal F., Curco A., Russo D.
Acta Chiropterologica
|
2009
|
tom 11
|
nr 1
Wetlands are internationally recognized as a crucial habitat type for the conservation of many migratory birds. Despite the fact that many bats are also long-distant migrants, the importance of foraging habitats for sustaining migrant bats has to date received little attention. We analyzed habitat selection patterns in the migrant bat, Nathusius’ pipistrelle Pipistrellus nathusii, in the southernmost part of its range (Iberian Peninsula), an area in which both mating and hibernation occur. We found that natural wetlands and riparian habitats (Phragmites reed beds) were positively selected, whereas human-transformed aquatic habitats (rice paddies) were avoided. Although semi-natural human-managed wetlands are perceived as being valuable for many species, our data emphasizes the importance of preserving natural wetlands (including riparian forests) as appropriate habitats for sustaining crucial phases of the life cycle of this bat. Agricultural transformation of the land is likely to be detrimental to this species since it reduces the availability of its preferred foraging habitat.
10

Foraging ecology in Mihely's horseshoe bats: Influence of habitat structure and water availability

76%
Salsamendi E., Arostegui I., Aihartza J., Almenar D., Goiti U., Garin I.
Acta Chiropterologica
|
2012
|
tom 14
|
nr 1
The climate in Mediterranean ecosystems is characterised by aestival hot temperatures and water shortages which may affect the behaviour of bats living in these environments. We evaluated the influence of habitat type, habitat structure, and water availability on the foraging behaviour of the Mehely's horseshoe bats (Rhinolophus mehelyi) using classification and regression tree (CART) analysis. Twenty-five individuals were successively radio-tracked during May and June in two colonies (Marias and Aurora) of south-western Spain. Twelve females were tracked in Marias and 13 males in Aurora. Both localities differed in the availability of habitat types: in Marias savannah-like oak woodland dominated the landscape (81% of the study area), whereas in Aurora pasture were dominant (64% of the area). Rhinolophus mehelyi always foraged in woodland; preferentially in cluttered spaces, but also in less-cluttered/more-open ones, while open spaces were completely avoided. Bats foraged close to water bodies, preferentially at distances below 500 m, where they may readily have access to drinking water or may encounter higher insect abundances. The similarity between sexes on the preferences of habitat structure and distance to water suggest that the disparity in the habitat types used by males in Aurora and females in Marias may be due to local availability. Riparian forest is an important habitat for foraging and commuting, and should be scrupulously protected. Conservation strategies should also include the protection of woodland of diverse structure and linear landscape elements. We recommend the creation of water bodies in woodlands to enhance the suitability of foraging sites that might be underused.
11

Diet and prey selection in Mehelyi's horseshoe bat Rhinolophus mehelyi (Chiroptera, Rhinolophidae) in the south-western Iberian Peninsula

76%
Salsamendi E., Garin I., Almenar D., Goiti U., Napal M., Aihartza J.
Acta Chiropterologica
|
2008
|
tom 10
|
nr 2
We studied diet and prey selection in Mehelyi's horseshoe bats Rhinolophus mehelyi in the south-western Iberian Peninsula, during the breeding seasons of 2003, 2006, and 2007. Faecal pellets were collected individually and arthropod fragments identified to family level, where possible. Arthropod availability was assessed using Malaise traps. Selection analyses were performed using Compositional Analysis and a Chi-square goodness-of-fit test. The bulk of the diet of R. mehelyi consisted of Lepidoptera, representing more than the 80% of the consumed volume on average (excluding juveniles), and more than 90% of the average percentage occurrence. This pattern was consistent across localities. Neuroptera and Tipulidae were locally abundant. Other important prey categories were Chrysomelidae, Brachycera, and Chironomidae. ANOVA tests showed that there were no significant differences between males and females in consumed prey categories, whereas juveniles consumed significantly less Lepidoptera than adults. Lepidoptera was the first prey category in the preference rank, followed by Myrmeleontidae, Chrysopidae and Tipulidae, and all of these were consumed more than expected by chance. This work shows that R. mehelyi is a moth specialist and suggests that juveniles may acquire this strategy while gaining hunting experience. Given the similarities in echolocation call characteristics and diet in the sibling R. mehelyi and R. euryale, they may compete for trophic resources in sympatry. Nevertheless, subtle differences in wing morphology between both species are probably large enough to permit spatial resource partitioning.
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