Cardioderma cor
heart-nosed bat

Heart-nosed bats, Cardioderma cor, are found mainly in eastern Africa. The range of this species extends from eastern Sudan to the northern tip of Tanzania, and as far south as the southern tip of Zambia (Csada, 1996).

Typical habitats for C. cor include dry lowlands and coastal strip habitats, and they are sometimes found foraging in river valleys. They are not found at elevations greater than 940 m. C. cor roosts during the day in abandoned buildings, dry caves, or in the cavities of Baobab trees. They usually roost in large colonies and prefer not to share the roost with other species of bats (Vaughan, 1976).

C. cor is relatively large for a microchiropteran, with a mass of 21 to 35 g and a body length of 70 to 77 mm. The fur covering the body is blue-gray in color and is long and loose. This species lacks an external tail and the interfemoral membrane is well developed. The eyes of this bat are large. The ears are connected at the base. The leaf-like nose is heart-shaped, and has a tragus with a rounded inner lobe. Physically, C. cor can be distinguished from Lavia frons, the only other African megadermatid, by skull and tooth features. This species does not go through torpor and is homeothermic. The dental formula of C. cor is: i 0/2, c 1/1, p 1/2, m 3/3 = 26 (Csada, 1996).

Mated pairs are monogamous and make an effort to retain the same mate during consecutive breeding seasons. Mated pairs have a territorial breeding site that is defended by the male, who sings from perches in the evening before foraging. These sites are typically established during the breeding season and break down afterward. (Vaughan, 1976).

Studies in Kenya have suggested that breeding territories and mated pairs may exist for an extended period of time (Nowak, 1999)

Most reproduction occurs in each of the two rainy seasons, March-June and October-December, although lactating females have been caught throughout the year. The reproductive season may be extended in some areas (Nowak, 1999).

Gestation lasts for approximately three months, after which the female gives birth to one hairless and blind pup. The mother carries the pup for two months (Csada, 1996). The young are probably weaned around three months of age (Nowak, 1999). After two months the young follow their mother while she forages, possibly allowing young bats to learn the foraging routine and territories.

As in all mammals, the female lactates, producing milk as food for her single offspring. She carries her young with her for two months, after which time the pup follows her on foraging trips (Csada, 1996). Male parental care is not known, although some might consider the maintenance of the breeding territory through song as a means by which the male provides the female and young with food resources.

The longevity of these bats is not known.

These bats are nocturnal. C. cor emerges from its roost just before sunset. The feeding site is usually less than 1 kilometer away and is reached through short flights with stops to perch in low vegetation. C. cor uses a "sit-and-wait" hunting strategy while hanging upside down from a perch in the low vegetation, usually 5-3 meters above the ground. From its perch, C. cor scans the area below by twisting its body 180 degrees and surveying with eyes and ears. When a prey item is detected, these bats fly down, seizing the prey and quickly carrying it back to the perch. There, the legs and wings are removed before the body is eaten.

During the wet season, when insects are in high abundance, C. cor will exhibit a "hawking" strategy to collect moths. It gleans locusts and katydids from vegetation. In contrast, during the dry season, terrestrial insects are taken. Also, during the dry season flights from the roost are usually longer than 1 kilometer and consist of longer periods of flight between perches (Vaughan, 1976).

Certain ticks and mites parasitize C. cor, and to reduce these ectoparasites these bats will spend 1 hour per day grooming themselves or other bats. Even though the social bonding implications of grooming in other species are well known, no research has been conducted to demonstrate any social significance to grooming in this species (Vaughan, 1976).

C. cor is essentially an insectivore with variations in diet affected by the alternation of the wet and dry seasons in Africa. In the wet season, these bats feed primarily on terrestrial beetles of length greater than 25 mm, but will supplement their diet with locusts, katydids, moths, and small vertebrates such as bats and frogs. In the dry season these bats depend on terrestrial beetles from the families Scarabeidae, Tenebrionidae, and Carabidae, with centipedes and scorpions consumed sometimes. Although feeding primarily on terrestrial beetles, these bats will also take advantage of leaf gleaning for insects and "hawking" moths when these prey are in abundance (Vaughan, 1976).

There are no known predators of C. cor (Csada, 1996). However, it is likely that typical bat predators, such as snakes, small cat species, and owls prey on young and on bats emerging from roosts.

Because of its feeding behavior, C. cor probably regulates insect populations, including crop pests.

C. cor helps to control insect populations that could otherwise damage crops (Csada, 1996).

C. cor carries bacteria (Borrelia sp.) that can cause relapsing fever in humans (Csada, 1996).

The species is listed as a low threat but is vulnerable.