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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
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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

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
|
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.
3

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.
4

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
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2008
|
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.
5

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.
6

Population trends of cave-dwelling bBats in the Eastern Iberian Peninsula and the effect of protecting their roosts

76%
Machado M. C., Monsalve M. A., Castello A., Almenar D., Alcocer A., Monros J. S.
Acta Chiropterologica
|
2017
|
tom 19
|
nr 1
Populations trends of cave-dwelling bats in the Eastern Iberian Peninsula and the effect of placing a perimeter fencing around their roosts (to avoid human disturbance on breeding colonies) were evaluated from 1997 to 2014. The species with the highest relative abundance was Miniopterus schreibersii (62.4%), followed by Myotis myotis/blythii (18%), and both populations showed positive trends. On the other hand, Myotis capaccinii (6.2%), M. escalerai (4.8%) and M. emarginatus (0.9%) showed significant, but minor increases, particularly in recent years. Rhinolophus mehelyi (0.2%) displayed no significant trends, while a moderate population decline was recorded for R. euryale (5.1%). Rhinolophus ferrumequinum (2.2%) and R. hipposideros (0.1%) showed positive growth trends. The main assemblages in the evaluated roosts were formed by Myotis myotis/blythii, Miniopterus schreibersii and R. ferrumequinum. This denotes their less specific requirements or greater flexibility when selecting roosts, compared with other species, except for M. capaccinii and R. mehelyi. No significant differences were found between roosts with different levels of protection, but there were positive trends in the protected roosts. Most non-fenced cavities showed negative trends during the period evaluated. We did not rule out other factors, such as requiring habitats with optimum food sources next to maternal roosts, which could affect population growth. The selectivity of some species of bats for certain caves will be essential for the preparation of management plans for certain roosts. Four of the seven risk factors documented for European bats affect studied population. Myotis blythii, M. myotis and Rhinolophus euryale would be most affected by a reduction in the areas they currently occupy.
7

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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