European Free-tailed Bat (Tadarida teniotis)
This bat is rather large as it is from 8.1 to 9.2 cm long. It has a unique head with rigid ears that are slanting forward (1), big eyes and a long nose. Their main characteristic is the tail, which extends beyond the membrane (2), although they tend to retract it while flying. This bat's tail is from 3.7 to 5.7 cm long and it is used as a touch sensor when they go out of the caves, walking backwards. Their wings are rather wide and short. The forearm is from 5.7 to 6.4 cm long. Their fly in a similar way as a swift, as their wings go backwards, and their neck is long. Their fur colour is light greyish-brown with some grey or white parts. Their stomach is lighter, and the tail is tick and fleshy. Females weigh more than males, but they are similar in size. These animals emit echolocation calls with frequency between 9 to 15 kHz, which can become higher during hunting (20 to 35 kHz). This buzzing can be heard by humans.
They live in rocky areas which are well preserved and close to water, where they usually hunt. They shelter in holes and cracks between the rocks and cliffs close to water. They share their shelters with swifts and other bats. Sometimes they choose bridges and walls. They prefer to roost in high rocky areas. They can be seen at the sea level and up high in the mountains. Not much is known about their biological changes in winter. This species goes through a partial migration, in which only one part of the colony is migratory. They also undergo short torpor state during bad weather, especially, storms. The colonies decrease in the number of individuals in winter and at the end of spring and summer, when they are also less active.
How They Live
These bats are nocturnal, and their diet is rather generalized although they mostly feed off large insects. They go after their prey round rivers, reservoirs and above the nearby pine and cork oak groves, at an altitude of 20 to 50 metres above the trees and mountain tops. They hunt alone or in small groups during the migrations of insects when there are plenty of them. They make use of thermal soaring to fly up, like big soaring birds, and hunt at higher levels. They can reach speed of 50 km/h. The free-tailed bat's colonies are small, with population less than 200 individuals. They can move up to 30 km away from their roosts, although their territory is likely to cover round 5 km away from their shelters.
This species has a complicated reproductive tract with two peaks in reproductive events. First reproductive peak is in spring and the other starts in August. The births happen, above all, between June and July. The births in the second period are later.
Males make kinds of harem groups of several females that he defends fiercely. They are very territorial. In late pregnancy, females abandon their shelter to give birth in other place where they stay with the young until they make new colonies of the young in Autumn. Afterwards, they go back to the harem with the dominant male.
Places Where They Can Be Seen
This species is rare and not common in the province. As for the distribution, they are rather scattered. There are few recorded locations of the species: at the boarder with Cadiz, in the Cortes Mountains and the Guadiaro Valley; and before this, they have been seen in the Sierra de Aguas because they accidentally crashed in the wind park. They is likely to be another colony in El Chorro as the conditions there are perfect for this species. It has been spotted along stages 20 and 24 on the Great Málaga Path.
The free-tailed bat's colonies smell of celery because males use it to mark their young's shelter. The species uses echolocation calls to detect large soft insects, which also have very developed sense of hearing and can hear and avoid bats that emit sounds of other frequencies. This type of buzzes or pulses prevent an insect from hearing the bat coming closer and escape. The disadvantage these bats have is that they cannot detect or catch small faster insects.