| Cave-dwelling bats are not only an important group in the Chiroptera,but also the key to energy flow and matter cycle in the cave ecosystem.Therefore,the species,diversity,population size,distribution and behavioral characteristics of cave-dwelling bats were of extremely significance in ecology and conservation biology.However,there had been a lack of satisfactory research methods for the quantity survey of bats,because traditional research methods were time-consuming,laborious and poor results.On the other hand,it was difficult to study for cave-dwelling bats in the wild due to their special roosting cave environments and preculiar biological habits.In this paper,we observed the populations of cave-dwelling bats based on Infrared Camera Trap Technology,which was widely used for wild animal investigation.Although it was available for the fieldwork of cave-dwelling bats by our trials,some notable problems had been appeared.In order to solve these problems,we provided a new method hereafter.In addition,a new genus and species of batblood-sucking landleech were identified from caves in Xiangxi Prefecture during our investigation of bats.The main results were as follows:1.Cave environments were humid-dark and bats were small and of flight,but our trial results indicated that camera traps could be used for ecology research of cave-dwelling bats in spite of having spme new problems to be dealted with.The video by camera traps showed that the same roostpoint could be used repeatedly by Rhinolophus sinicus(i.e.having “habitat preference”),and Hipposideros armiger might have a possible behavioral model of teaching their young flying during breeding(i.e.having "fly-teaching behavior").There were different applied effects by the different types of camera traps,but the same problems existed commonly such as slow triggering speeds,battery power insufficience,uncontinuous recording,narrow field of view,low-quality images,easy contamination and so on.2.Considering the shortcomings of camera traps in the wild ecological study of cave-dwelling bats,we invented a new device,a Field Portable and Active Infrared Video Recording Device.Compared with the Infrared Camera traps,the new device could automatically continously record the behaviors and activities of bat populations for at least two days as well as was of a wider vision field and high-quality images.When we set it in the cave entrance,it could clearly account the population size and activity rhythm of cave-dwelling bats.If laid under their roostsites in the cave,the device would record their behaviorals.3.In spite of some obvious advantages of the new device,it was still necessary to combine traditional methods to obtain reliable information about the species composition of cave-dwelling bats.In 2017,we monthly investigated 8 caves mainly for bat's species and population size,and there were about 10,000 individual-by-time bats belonging to 13 species and 4 families recorded,of which both H.armiger and R.sinicus were dominant.The species number and population size of bats were monthly different.The peak of population size appeared in August,and the valley in October.However,the maximum number of species did in October(10 species),and the minimum in June(6 species).Analysis of the monthly fluctation of population size iindicated that the H.armiger significantly affected the composition of Chiroptera in these caves,and it might have more competitive advantages than the other species.Additionally,the karst caves with long tunnels and large extrances had much higher speceis diversity and population size than those with short ones and small ones,which showed that cave-dwelling bats might tend to select large and medium-sized caves for roosting.4.During the field surveys of cave-dwelling bats,a species of batblood-sucking landleech was found in several caves in Xiangxi Prefecture.Based on morphological characteristics comparison and mitochondrial COI gene sequence analysis,it was identified as a new genus and species of Haemadipsidae,named Sinospelaeodella gen.nov.and S.wulingensis sp.nov.,and the new genus also included S.cavatuses comb.nov.,which was first accounted by Prof.Yang Tong in the institute of hydrobiology,Chinese Academy of Sciences in 2009.Although S.wulingensis and S.cavatuses were similar in many morphological aspects,it could be distinguished by body size,eyes,reproductive & digestive system and COI gene sequence.5.At present,the distribution of S.wulingensis was found only in the warm and humid rock walls of deep tunnels of six caves in Xiangxi Prefecture,with an elevation of 337m~1043m,air temperature of 10.9~22.1°C,relative humidity of 82.3%~100.0%,atmospheric pressure of 966.5~988.0hpa.Although S.wulingensis was monoecism,it was cross fertilization.It laid eggs and breeded all the year around.The larvae appeared mainly in Febrary to April and the reproductive individuals did mostly in September to October,which was closely related to bats' activity rhythm.S.wulingensis was temporary parasites in cave-dwelling bats for their population dispersion and migration,and we observed that the unique caveleech could bloodsuck various species of bats in spite of seemingly showing no interests in the blood of Human,mice and other animals.We speculated that the caveleech might exclusively suck bat's blood but certainly needed more evidence and further systematic research. |
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