Fruit Bat Cynopterus Sphinx Research Articles

Effect of moonlight on the foraging behaviour of a megachiropteran bat Cynopterus sphinx

AbstractWe studied the influence of moonlight upon the foraging activity pattern of the fruit bat Cynopterus sphinx. We observed the bats when foraging on the fruits of Calophyllum inophyllum and on the leaves of Mimusops elengi and Cassia fistula for 31, 27 and 28 days, respectively at the botanical garden in the Madurai Kamaraj University campus. The number of feeding bouts was recorded every hour between 18:00 and 05:00. A feeding bout involves a bat landing on the tree and collecting a part (or whole) of the fruit or a leaf. The total number of feeding bouts was negatively correlated with per cent moonlight each night. The number of feeding bouts decreased during the waxing phases of the moon. During the period of new moon the mean number of feeding bouts was significantly higher compared to the periods of other phases. During the first quarter and the last quarter phases, feeding occurred more during the dark part of the night, especially when the bats foraged upon M. elengi and C. fistula. While cloud cover enhanced the foraging activity, lightning and thunder suppressed it. Our study indicates that moonlight influences the foraging activity of C. sphinx.

Parentage, reproductive success and breeding behaviour in the greater horseshoe bat (Rhinolophus ferrumequinum).

Female greater horseshoe bats form maternity colonies each summer in order to give birth and raise young. During the mating period, females visit males occupying territorial sites, copulation takes place and sperm are stored until ovulation occurs, normally in April. Using microsatellite markers and a likelihood method of parentage analysis, we studied breeding behaviour and male reproductive success over a five-year period in a population of bats in south-west Britain. Paternity was assigned with 80% confidence to 44% of young born in five successive cohorts. While a small annual skew in male reproductive success was detected, the variance increased over five years due to the repeated success of a few individuals. Mating was polygynous, although some females gave birth to offspring sired by the same male in separate years. Such repeated partnerships probably result from fidelity for either mating sites or individuals or from sperm competition. Females mated with males born both within and outside their own natal colony; however, relatedness between parents was no less than the average recorded for male female pairs. Gene flow between colonies is likely to be primarily mediated by both female and male dispersal during the mating period rather than more permanent movements.

Tent Construction by the Short‐nosed Fruit Bat Cynopterus sphinx (Chiroptera: Pteropodidae) in Southern India

AbstractThe short‐nosed fruit bat Cynopterus sphinx (Chiroptera: Pteropodidae) constructs shelters by severing stems of the curtain creeper, Vernonia scandens, and stems and leaves of the mast tree, Polyalthia longifolia, creating partially enclosed cavities (stem tents) in which to roost. Our observations indicate that the construction and maintenance of stem tents are primarily, if not exclusively, the behaviour of single males. A stem tent is formed in V. scandens when a single male C. sphinx severs up to 300 small‐ to medium‐sized stems creating a partially flattened, bell‐shaped cavity, and in P. longifolia when a male severs a few medium‐ to small‐sized branches and many leaf petioles, creating an entry/exit portal and space in which to roost. A tent constructed in V. scandens is completed in approximately 30 d, whereas one in P. longifolia is completed in about 50 d. Stem‐tent construction takes place mostly at night, but some stem chewing occurs in late afternoon. At night a stem tent is occupied by a single male, whereas females are usually absent. During the day the number of bats occupying completed tents is highly variable, ranging from two to 19 females (and their pups) and a single adult male. Tent construction is annually bimodal, which corresponds to a biannual breeding season. A dominant male sometimes deposits saliva on branches inside his tent cavity and actively defends this space from intrusions by other males. Both behaviours suggest forms of scent marking and territorial display. Our observations indicate that dominant males construct tents, recruit females and then defend the tents (and their female occupants) for the purpose of gaining reproductive access. The variance in harem group size indicates that some tent‐making males are more successful than others in recruiting females.