Nyctalus lasiopterus

The greater noctule bat (Nyctalus lasiopterus) is a rare bat found in Europe, West Asia, and North Africa. It is the largest and least studied bat in Europe with a wingspan of up to 46 centimetres (18 in) and is one of the few bat species to feed on passerine birds. Greater noctule bats are the only bat species to hunt birds on the wing rather than when roosting. The greater noctule bat has wings adapted for open-air hunting and uses echolocation frequencies above the hearing range of birds. The greater noctule bat belongs to the suborder Microchiroptera and uses echolocation. Echolocation is a perceptual system where echoes are produced by emitting ultrasonic sounds. Echolocation allows bats to compare the outgoing pulse with returning echoes which produces detailed images of the bat's surroundings. With echolocation, bats are able to detect, localize and classify their prey in complete darkness. The greater noctule bat has been observed as only emerging from its roosts well after dusk when it is completely dark. The greater noctule bat has keen hearing and sense of smell, however its eyes are poorly developed. The wings of the greater noctule bat are thinner than those of birds which allow it to maneuver quickly and accurately. While its wing is delicate and rips easily, it is able to regrow. The greater noctule is the largest bat in Europe, with a wingspan of 41–46 cm (16–18 in). Its head-and-body length is from 8.4 to 10.4 cm (3.3 to 4.1 in), its tail is from 5.5 to 6.6 cm (2.2 to 2.6 in) and its forearm ranges from 6.2 to 6.8 cm (2.4 to 2.7 in). The body mass of adults ranges from 41 to 76 g (1.4 to 2.7 oz). The greater noctule bat has been observed as a high altitude flier and a low altitude forager. The dorsal fur of the greater noctule bat is uniformly reddish-brown to dark brown. Its muzzle is broad with enlarged short ears and its tragus (ear) is broad, short, and mushroom-shaped. Calcar, also known as calcaneum, is present and it reaches close to midway to the tail membrane. The greater noctule bat has a robust skull and its rostrum is square with an ordinary nasal slit. The zygomatic arches are very slender and the braincase is smooth, turned upwards. The sagittal crest is not present, while the lambdoid crest is well developed. Most of the projecting point of the skull is made up of exoccipital condyles. The basisphenoid is wide and deep and the tympanic bullae are relatively small. Even though the fossil record of bats extends over 50 million years, their fossils are extremely rare. The fossil record of the greater noctule in the Iberian Peninsula suggests that they lived at different geographical locations from that of today. The fossils of greater noctule are almost non-existent prior to the Miocene epoch. The deterioration of the climate at the end of Neogene led to the disappearance of tropical species and vespertilionids profited by accessing a wider range of habitats. The greater noctule bat is a tree-dwelling bat that roosts in trees all year round. It is found throughout the deciduous forests of Europe from the Iberian Peninsula to the Bosporus region of Turkey. The largest concentration of greater noctule bat is in the south western portion of Spain. The greater noctule bat is a tree-obligate species that prefers oak or beech trees that have a hollow space for day roosting. Greater noctule bats also roost in pine trees if there are no other options. Other studies have shown that this bat greatly prefers birch trees. This suggests that the greater noctule bat does not prefer a specific tree, but perhaps looks for the physical condition of the tree. It has been noted in several studies of greater noctule bat roosting behavior that different trees have different functions for the greater noctule bat, and that these tree-specific needs could affect roost selection for communities of greater noctule bats. Studies in Hungary (Ke´ kes peak, 1014 m a.s.l.) indicates that greater noctules prefer high roost locations. The study also hypothesizes that older, decayed trees are preferred by the species. While the majority of the world's bats are insect eaters, greater noctule bats regularly prey on birds. One study has shown that predation on birds accounts for over 80% of the greater noctule bat’s diet during periods of the year when the birds are migrating. The greater noctule bat switches its prey type opportunistically depending on the time of year. In addition, with the possible exception of the Asian great evening bat, the greater noctule bat is the only bat that hunts birds on the wing rather than when roosting. The greater noctule is well adapted for hunting passerines in the air. It employs echolocation, is large in size, has wings with a wingspan of up to 46 centimeters that are evolved for open-air hunting, and has echolocation frequencies beyond the hearing range of birds. N. lasiopterus is understudied due to its rarity; very little is known of its mating habits, reproductive pattern, life cycle and sex ratio. N. lasiopterus, as a Nyctalus species, has an outstanding capability for migration which can possibly result in considerable seasonal changes in sex ratio. The studies in North-East Hungary indicates that the sex-ratio differs greatly depending on the location. Males were exceedingly dominant in Greece and the Czech Republic while females were dominant in NE Germany, the Moscow-region, Voronezh, and NE Hungary. This sexual segregation is due to difference in sex-specific thermoregulatory and energetic requirements. The females are dominant in warmer locations because it is optimal for fetal development and milk production. On the other hand, males are dominant in cooler locations because of lower energetic demands. These results verified that N. lasiopterus have nursing colonies located in Hungary.