About Rhinolophus ferrumequinum (Schreber, 1774)
Rhinolophus ferrumequinum, commonly called the greater horseshoe bat, is the largest horseshoe bat found in Europe. It has a distinctive noseleaf structure: the upper portion is pointed, while the lower portion is horseshoe-shaped. This specialized noseleaf helps focus the ultrasound the bat uses for echolocation, or what the species functionally uses to 'see' its surroundings. The greater horseshoe bat has unique tooth and bone structures that set it apart from other rhinolophids (horseshoe bats). Its first upper premolar protrudes from the main row of teeth; in other horseshoe bats, this premolar is either very small or completely absent. Compared to its close relatives, the greater horseshoe bat also has relatively short third and fourth metacarpal bones in its wings, and it lacks a tragus. On average, the greater horseshoe bat is 57 to 71 millimeters (2.2 to 2.8 inches) long, with a 35 to 43 millimeter (1.4 to 1.7 inch) tail and a 350 to 400 millimeter (14 to 16 inch) wingspan. The species exhibits slight sexual dimorphism, with females being slightly larger than males. The fur of the greater horseshoe bat is soft and fluffy. The base of each hair is light grey, dorsal fur is grey-brown, and ventral fur is grey-white. Juvenile bats have fur with a more pronounced ash-grey tint. The bat's wing membranes and ears are light grey-brown. The greater horseshoe bat can weigh up to 30 grams (1.1 oz) and can live up to 30 years. The greater horseshoe bat has a broad distribution that spans from North Africa and southern Europe, through southwest Asia, the Caucasus, Iran, Afghanistan, Pakistan and the Himalayas, to southeastern China, Korea, and Japan. Its northernmost known population is located in Wales, and its range extends into the southern parts of the Netherlands, Germany, Poland and Ukraine. Generally, this species lives below 800 meters above sea level, but it can be found up to 3,000 meters above sea level in the Caucasus, where suitable roosts and appropriate humidity conditions are available. Common foraging habitats for the greater horseshoe bat include pastures, deciduous temperate woodland, and Mediterranean and sub-mediterranean shrubland and woodlands. In the northern portions of its range, the species uses warm underground sites (both natural and artificial) and attics as summer roosts. When greater horseshoe bats occupy buildings, important factors for occupancy include proximity to quality foraging areas, proximity to underground sites that can be used for torpor at different times of year and for winter hibernation, and the specific features of the building itself. During the winter, greater horseshoe bats hibernate in cold underground sites. The species requires specific ranges of temperature and humidity to roost, and these required ranges can vary based on the bat's age, sex, and physical condition. In the southern parts of the greater horseshoe bat's range, individuals remain active year-round. Greater horseshoe bats typically travel between 20 and 30 kilometers between their winter and summer roosts; the longest recorded travel distance between roosts for this species is 180 kilometers. In South Asia, the species also inhabits montane forests in the mountains and valleys of the Himalaya, where it roosts in tight clusters in caves, old temples, and old or ruined buildings. Male greater horseshoe bats reach sexual maturity at two years of age, while females reach sexual maturity at three years. Some females do not breed until they reach five years of age. The vast majority of matings occur in the fall, though a small number of matings happen in the spring. This species' reproductive behavior has been studied in detail. During the mating period, females visit males that roost in small caves. The species' mating system is most accurately described as polygynous, with multiple females visiting individual males. However, genetic evidence shows that some female greater horseshoe bats will visit and mate with the same male partner across multiple successive years, which indicates that some pairs practice monogamy or mate fidelity. Notably, related females have been found to share sexual partners; this behavior may work to increase overall relatedness and social cohesiveness within the colony. Male greater horseshoe bats vary in their reproductive success, and do not tend to show strong reproductive skew within a single year. Over multiple years, however, reproductive skew becomes strong, as certain males achieve repeated mating success across seasons. After mating, the seminal fluid coagulates inside the female's vulva to form a plug. This plug likely functions either to prevent subsequent matings by other males, or to increase the chance that sperm are retained for successful fertilization. There is some evidence that females can eject these plugs, which suggests females may be able to exert some control over which fertilizations occur. Females raise their young in communal maternity roosts, and show strong fidelity to the sites where they themselves were born, a trait called natal philopatry. Each breeding season, a female produces exactly one offspring. Most young are born in June or July. Young bats can open their eyes when they are seven days old, and they are able to fly by their third or fourth week of life. Young bats typically leave the maternity roost five weeks after birth.
