Echolocation Calls And Summer Foraging Strategy Of Rhinolophus Macrotis

At every night from July to August 2005, the field work was conducted at Xianren Cave(102°20′E,24°30′N) at Fagudian County in Yunnan, China. The field lab (9 m ×4 m×4 m)was established with bamboo and nylon net (25mm×25mm). As a studying object, the bodysizes of bats of Rhinolophus macrotis were measured, as well as the echolocation calls wererecorded and analyzed, and the foraging behavior was observed. At the same time, theremains of the insects that bats preyed were collected, so that the summer diets wereidentified.(1)At the states of flying and hanging, the calls of bats of Rhinolophus macrotis wereboth FM-CF-FM with 2-4 harmonics. The dominant frequency concentrated in 2nd harmonic.Except the dominant frequency and interpulse interval, all the other parameters of the callsemitted during flying were higher than those of calls emitted during hanging. Some time thebats can produce calls with 3-4 harmonics during flying.(2) The bats of bats of Rhinolophus macrotis mainly preyed insects of lepidoptera,including 8 families, such as Geometridae(37.9%,quality percent), Lasiocampidae(24.1%),Noctuidae (20.7 %) and so on.(3)The bats of Rhinolophus macrotis can forage by strategies including air flyingcatching and gleaning, but they couldn't flying catch. They caught insects mostly though airflying catching, and caught big insects except lepidoptera through gleaning.The relationship between diet and morphology, insects size and foraging habitats wasdiscussed, which could be the base of further study on co-evolution between bats ofRhinolophus and insects of lepidoptera and could supply directive significance for batsprotection and prevention and curing of plant diseases and insect pests.