The greater horseshoe bat (Rhinolophus ferrumequinum) is a European bat of the Rhinolophus genus. Its distribution covers Europe, Africa, South Asia and Australia. It is the largest of the European horseshoe bats and is thus easily distinguished from other species. The species is sedentary, typically travelling up to 30 km between the winter and summer roosts, with the longest recorded movement being 180 km. The species is notable as having the oldest recorded age for any European bat, with a bat living for over 30 years. The frequencies used by this bat species for echolocation lie between 69–83 kHz, have most energy at 81 kHz and have an average duration of 37.4 ms
The greater horseshoe bat is the largest bat in Europe. It has a distinctive noseleaf, which has a pointed upper part and a horseshoe shaped lower part. Its horseshoe noseleaf helps to focus the ultrasound it uses to 'see'. The greater horseshoe bat also has tooth and bone structures that are distinct from that of other rhinolophids. Its first premolar on the upper jaw protrudes from the row of teeth. For other horseshoe bats, this premolar is very small or non-existent. Also in comparison to its relatives, the greater horseshoe bat has relatively short third and fourth metacarpal bones in its wings. It also lacks a tragus. The Greater Horseshoe Bat is on average between 57 and 71 mm long, with a 35–43 mm tail and a 350–400 mm wingspan. The fur of the species is soft and fluffy, with the base of hairs being light grey, the dorsal side hair grey brown and the ventral side grey-white, with juvenile bats having more of an ash-grey tint to their fur. Wing membranes and ears are light grey-brown. It weighs up to 30 grams.
The greater horseshoe bat ranges from North Africa and southern Europe through south-west Asia, the Caucasus, Iran, Afghanistan, Pakistan and the Himalayas to south-eastern China, Korea, and Japan. Generally the bats lives below 800 m asl, but it also lives, depending on roost availability and humidity, 3,000 m asl in the Caucasus
Pastures, deciduous temperate woodland, Mediterranean and sub-mediterranean shrubland and woodlands are common foraging habitats for this species.[1] In northern parts of its range, the horseshoe uses warm underground sites, both natural and artificial, as summer roosts as well as attics. Where the species occupies buildings, proximity to good foraging areas and underground sites for torpor at various times of year and for winter hibernation as well as the building's own features are important.
Horseshoe bats hibernate in cold underground sites like large caves, during the winter. The bat require a certain temperature and humidity limit, but thus can vary with age, sex and condition.[1] Horseshoe bats are active throughout the year in the southern parts of their range. Horse bats commonly travel distances of 20–30 km between winter and summer roosts, with longest distance recorded being 180 km. Horseshoes bats also live in montane forests among the mountains and valleys of the Himalaya in South Asia and roosts in caves, old temples, old and ruined buildings in tight clusters.
The species feeds preferentially on lepidoptera (moths), making up around 41% of the diet - in particular the noctuidae species., Coleoptera (beetles) constitute around 33% of the diet, of which dung beetles are often taken. Aphodius rufipes is one such dung beetle forming an especially important part of its diet. Cow pats are part of its life cycle, acting as a food source and habitat for the larvae. Up to 100 larvae can be found in a single cow pat. The beetle is most abundant in August when the young bats begin their first feeding flights). The remainder of the diet consists of Hymenoptera and Diptera species. Cockchafers also form an important part of its diet.
The feeding area from the maternity roost is typically of radius 4 km, as neither the lactating females or young can travel far. In late August and September the bats feed oncranefly, to fatten up before hibernation. Breeding females depend on beetles from April until June, and moths from June to August.
The Greater Horseshoe Bat leaves its roost at dusk. Its flying is made up of slow, fluttering travel with short glides, normally between 0.3 and 6 metres above the ground. Little hunting is done during wet and windy weather. It hunts in terrain with poor tree cover such as hillsides and cliff faces, and in gardens where it locates insects from a resting place and then intercepts them. The species has the ability to pick food up off the ground while still in flight, and indeed drinks during low-level flight or while hovering. The feeding range of colonies in England is between 8 and 16 kilometres.
Female bats become sexually mature at the age of three years while males are sexually mature at two years. Some females may not breed until their fifth year. Most matings take place in the fall, however some occur in the spring. The reproductive behaviour of this species has been studied in detail. During the mating period, females visit males that are roosting in small caves. The mating system is best described as polygynous, with multiple females visiting males. However, genetic evidence has shown that some female greater horseshoe bats will visit and mate with the same male partner over successive years, indicating monogamy or mate fidelity. Curiously, related females have also been found to share sexual partners, which might serve to increase relatedness and social cohesiveness in the colony. Males vary in their reproductive success but do not tend to show reproductive skew within a year. However, over several years, skew becomes strong due to the repeated success of particular males.
After mating, seminal fluid coagulates in the female’s vulva to form a plug, which probably functions either to prevent subsequent matings by other males, or to increase the chances that the sperm are retained for successful fertilzation. There is some evidence that females can eject these plugs, suggesting that they may be able to exert some control over fertilizations which take place. Females raise their young in communal maternity roosts, and show strong fidelity to the sites where were themselves were born (so-called natal philopatry). Each season, a female produces one offspring. Most young are born in June or July.[5] When they are seven days old, young can open their eyes and at their third or fourth week they can fly. Young can live the roost their seventh or eighth week
From Wikipedia, the free encyclopedia
Photos and video Geri , Pomos, Mammari by George Konstantinou
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