中华山蝠的生长发育及年龄估算

1997 年5 ～9 月,采用标志重捕法对中华山蝠的生长发育进行研究,共观察幼蝠388 只次(雄性184 只次,雌性204 只次),结果显示:中华山蝠幼蝠20 d 前体重和前臂长均呈直线增长,日平均生长率分别为0.57 g/d 与1.36 mm/d, 回归方程为:体重=3.05 + 0.57×日龄, 前臂长= 15.49+1.36×日龄。20 d后增长减慢, 大约5 周龄后开始飞行,初飞幼蝠与成体的体重差异显著,前臂长与成蝠差异不显著。中华山蝠幼体生长与Logistic、Von Bertalanffy 及Compertz 3 种生长曲线模型的拟合度均较高, R² 值超过0.93。前臂长的增长用Logistic曲线拟合最合适,体重的增长用Von Bertalanffy 曲线拟合最合适。根据前臂长以及第四掌骨与指骨间软骨的发育模式,得到出生后1 ～ 76 d幼蝠的年龄鉴定方程式。当前臂长≤43.32 mm时,日龄= -10.77 +0.71 × 前臂长;当前臂长> 43.32 mm时, 日龄= 71.10 - 9.89 ×第四掌骨与指骨间软骨长。      

Postnatal growth in the Long-fingered Bat,Miniopterus schreibersii pallidus,in Iran (Chiroptera: Miniopteridae)

This study describes the postnatal development of body mass, forearm length and epiphyseal phalangeal gap in a free ranging population of the Long-fingered Bat, Miniopterus schreibersii pallidus Thomas, 1907, in a maternity roost in the Mahidasht cave in western Iran. The pups at birth had a mean body mass of 3.74?±?0.09 g and forearm length of 24.3?±?0.31mm. The length of forearm and body mass increased linearly during first two weeks, and thereafter maintained an apparent stability. The epiphyseal gap of the fourth metacarpal phalangeal joint increased until the thirteenth day, then decreased linearly until the 70th day and thereafter fused. The rate of body mass gain and forearm growth during the first 13 days was 0.54 g/day and 1.39 mm/day, respectively. Initiation of flight occurred three weeks after birth. A method of estimating age was derived from the values of the forearm length and the total gap of the fourth metacarpal-phalangeal joint during the pre-flight and post-flight periods.     

中华山蝠翼的形态学发育模式

为了揭示中华山蝠翼的形态学发育模式,2012-2014年, 通过对50只中华山蝠幼蝠进行人工饲养实验观察及测量,辅以野外标志重捕,研究中华山蝠翼的生长。结果显示：中华山蝠翼外形各量度值先呈直线增长,后增长速度逐渐减慢。各指标增长速度减慢的日龄各不相同,臂膜长在25日龄生长速度逐渐减慢;翼展、翼面积、臂膜面积在30日龄增长速度减慢;掌膜长及掌膜面积则在40日龄增长速度减慢。臂膜长发育最快,试飞前 (28日龄) 已达到成体臂膜长的80.9%。翼载在幼蝠生后14日龄内呈直线增长,然后开始直线下降,到试飞期 (35日龄左右),翼载值降到最低,是成体翼载的80.0%,此后呈极缓慢增长趋势。中华山蝠翼的生长主要集中在试飞前。试飞后,则通过减缓体重的增长速度甚至减轻体重,保持翼面积尤其是掌膜面积的增长速度,从而降低翼载,以便更快地适应飞行生活。Logistic, Von Bertalanffy和Gompertz 3种非线性曲线中,Gompertz模型对翼展拟合度最佳,Gompertz和Von Bertalanffy模型对翼面积拟合度优于Logistic曲线。     

Wing morphology and flight development in the short-nosed fruit bat Cynopterus sphinx

Postnatal changes in wing morphology, flight development and aerodynamics were studied in captive free-flying short-nosed fruit bats, Cynopterus sphinx. Pups were reluctant to move until 25 days of age and started fluttering at the mean age of 40 days. The wingspan and wing area increased linearly until 45 days of age by which time the young bats exhibited clumsy flight with gentle turns. At birth, C. sphinx had less-developed handwings compared to armwings; however, the handwing developed faster than the armwing during the postnatal period. Young bats achieved sustained flight at 55 days of age. Wing loading decreased linearly until 35 days of age and thereafter increased to a maximum of 12.82 Nm(-2) at 125 days of age. The logistic equation fitted the postnatal changes in wingspan and wing area better than the Gompertz and von Bertalanffy equations. The predicted minimum power speed (V(mp)) and maximum range speed (V(mr)) decreased until the onset of flight and thereafter the V(mp) and V(mr) increased linearly and approached 96.2% and 96.4%, respectively, of the speed of postpartum females at the age of 125 days. The requirement of minimum flight power (P(mp)) and maximum range power (P(mr)) increased until 85 days of age and thereafter stabilised. The minimum theoretical radius of banked turn (r(min)) decreased until 35 days of age and thereafter increased linearly and attained 86.5% of the r(min) of postpartum females at the age of 125 days.     

Postnatal development of morphological features and vocalization in the pomona leaf-nosed bat <Emphasis Type="Italic">Hipposideros pomona</Emphasis>

Based on mark-recapture data, we studied the postnatal development of morphological features and vocalization of the pomona leaf-nosed bat (Hipposideros pomona). Morphological changes indicated that body mass and length of forearm followed a linear pattern of growth until 13 days of age at mean growth rates of 0.14 g/day and 1.08 mm/day, respectively, and thereafter, growth rates slowed. The length of the total epiphyseal gap of the fourth metacarpal–phalangeal joint showed a linear increase for up to 10 days, followed by a linear decrease until day 40 at a mean rate of 0.09 mm/day. Together, two equations permitted estimation of the age of H. pomona pups between 1 and 40 days. The logistic equation provided the best fit to the empirical curves for body mass and length of forearm. Studies of vocal development showed that the precursors of echolocation calls were not emitted until day 7 after birth. As the pups grew, the dominant frequency (DF) of isolation calls increased and number of harmonics (NH) decreased, whereas the duration remained relatively stable. The DF and BFM₂ (the bandwidth of the terminal frequency-modulated sweep from the second harmonic) of the early echolocation calls increased; however, the NH and duration decreased.     

Postnatal development in Andersen's leaf-nosed bat Hipposideros pomona: flight, wing shape, and wing bone lengths

Postnatal changes in flight development, wing shape and wing bone lengths of 56 marked neonate Hipposideros pomona were investigated under natural conditions in southwest China. Flight experiments showed that pups began to flutter with a short horizontal displacement at 10 days and first took flight at 19 days, with most achieving sustained flight at 1 month old. Analysis of covariance on wingspan, wing area, and the other seven wing characteristics between ‘pre-flight’ and ‘post-volancy’ periods supports the hypothesis that growth had one ‘pre-flight’ trajectory and a different ‘post-volancy’ trajectory in bats. Wingspan, handwing length and area, armwing length and area, and total wing area increased linearly until the age of first flight, after which the growth rates decreased (all P < 0.001). Wing loading declined linearly until day 19 before ultimately decreasing to adult levels (P < 0.001). Additionally, the relationship of different pairwise combinations of bony components composing span-wise length and chord-wise length was evaluated to test the hypothesis that compensatory growth of wing bones in H. pomona occurred in both ‘pre-flight’ and ‘post-volancy’ periods. The frequency of short-long and long-short pairs was significantly greater than that of short-short, long-long pairs in most pairs of bone elements in adults. The results indicate that a bone ‘shorter than expected’ would be compensated by a bone or bones ‘longer than expected’, suggesting compensatory growth in H. pomona. The pairwise comparisons conducted in adults were also performed in young bats during ‘pre-flight’ and ‘post-volancy’ periods, demonstrating that compensatory growth occurred throughout postnatal ontogeny.     

两种果蝠对光叶桑(Morus macroura)果实的取食及种子传播

从2005年3月到2006年5月,在中国科学院西双版纳热带植物园沟谷雨林保护区内研究了两种果蝠——棕果蝠(Rousettus leschenaulti)和犬蝠(Cynopterus sphinx)取食光叶桑(Morus macroura) 果实的行为、夜栖息地分布、散布种子方式及范围等。借助月光对果蝠的行为进行直接观察,发现它们的取食活动一般在天黑20~40 min开始,取食高峰发生在22: 00~22: 30 和23:00~23:30之间,这两个取食高峰期平均取食次数(平均值±标准误)为(13.5±2.5)和(15.0±2.3)次,最低的取食频率发生在19: 00~19: 30和20: 30~21: 00之间,分别取食(0.2±0.2)和(0.7±0.5)次。果蝠很少在母树上取食成熟的果实,相反它们用嘴叼下果实并携带到夜栖息地去进食,通常这些夜栖息地是具有密闭树冠、密集枝条的树种。夜栖息地在母树周围的分布根据环境中适合它们栖息的树种和分布而决定,不同母树周围其夜栖息地分布具有非常大的变异与空间异质性。钝叶榕(Ficus curtipes)、铁力木(Mesua ferrea) 和糖胶树(Alstonia scholaris) 是果蝠最喜爱的夜栖息地。在同样的情况下,尽管需要飞行更远的距离,两种果蝠都比较喜欢寻找具有许多枝条和小枝并且有复杂树冠的树木作为夜栖息地。两种果蝠取食光叶桑果实时,一部分种子通过消化道消化后被排泄出来,另外的一部分伴随着咀嚼后的果渣被吐出来,通过这两种方式,散布了大量的种子,再加上在飞行中也有排泄的习性,它们传播的种子在空间上更广泛。     

草原兔尾鼠的生长发育

在人工饲养条件下，对初生至１００日龄的草原兔尾鼠进行逐日观察，并测量其个体的体重、体长、尾长、、后足长、记录其生长发育特征。幼鼠睁眼期为１０－１２日龄；自由采食期为１５－１８日龄；断奶期为１９－２０日龄；性成熟期为４５－６０日龄。生长发育大致分为四个阶段；乳鼠阶段，初生至１５日龄，体长７０毫米以下；幼鼠阶段，１６－３０日龄，体长７０－８４毫米；亚成体阶段，３０－６０龄，体长８５－９２毫米；成体阶段     

Development of Prey Capture in the Indian False Vampire Bat Megaderma Lyra

We studied development of prey capture, under captive conditions, on five newly weaned Indian false vampire bats Megaderma lyra. We tested the hypothesis that the young bats are able to improve the ability of hunting by trial and error. An additional hypothesis was that their rate of prey consumption and method of handling prey improve with age. We separated the juveniles from their mothers and observed them individually at different ages. At 58 d of age, M. lyra roosted 2 m above floor level, flew down only towards moving frogs, landed >1 m away from them and returned to roosts without showing attempt to capture. At day 60, bats roosted at 50‐cm heights, landed approx. 1 m away from frogs and moved towards them. Although bats intercepted frogs, their attempts to capture were still unsuccessful. At day 62, bats landed <1 m from frogs, made similar attempts and most of them were successful. Bats carried frogs, roosted at heights of 100 cm and started consuming. Numbers of jumps made by frogs and attempts made by bats during successful captures decreased with increase in age of bats. Furthermore, the distance between landing sites of bats and places where frogs stayed during landings decreased with advancement of age. Until 75 d of age, M. lyra devoured frogs with legs‐first on significantly more occasions. After 75 d, most of the consumptions started with heads of frogs, similar to adults. Duration of feeding on single frogs was significantly longer compared with that of mothers until young were 75‐d old. The study revealed that juveniles were inefficient on localization, rate of consumption, and handling prey at earlier ages (e.g. 60 d). They became efficient on these behavioural components at later age, i.e. after 75 d. Thus, the results were in accordance with both the hypotheses. Bats did not respond to stationary frogs.     

Development of wing morphology in the Indian pygmy batPipistrellus mimus

The growth and development of the wing parameters of the Indian pygmy batPipistrellus mimus was studied under natural conditions. Newborn young were marked with nontoxic coloured paint and were later marked with split rings. The wingspan and wing area showed linear growth until the age of five weeks, after which the rate of growth decreased. The observations on flight showed that at the age of 19 days the young were able to flutter their wings, at the age of 22 days they flew for a short distance and at the age of 29 days they exhibited sustained flight. The development of wing loading and aspect ratio are also presented. The decrease in wing loading as the bat grows is discussed as an advantage to sustain flight. The aspect ratio showed a high degree of scatter at early stages of life which decreased at the later period of growth. In general the development of wing morphology ofP. mimus is similar to that of other vespertilionid bats.     

Abundance, biology, and human exploitation of bats in the Palau Islands

Three species of bats, Pteropus pilosus, P. muriannus pelewensis , and Embullonura semicaudata palauensis , were surveyed by observations, systematic counts, and interviews with local residents in the Palau Islands of Micronesia during a one-month period in 1991. Pteropus pilosus is presumed extinct, with no observations made this century. Pteropus m. pelewensis occurred throughout the archipelago. It is less colonial than other subspecies of P. muriannus , with most of the population appearing to roost solitarily or in small groups of a few bats. Colonies were uncommon and typically ranged in size from about 30–200 animals. Evidence of two larger roosting concentrations, one of which may have held as many as 3,000 bats, was also found. These fruit bats forage and roost in a variety of forested habitats and have diverse diets known to contain the fruits of 54 species, the flowers of 28 species, and the leaves of one species. At dusk, most bats began foraging within several kilometres of their day roosts, but some flew at least 12 km to reach feeding sites. The largest numbers of P. m. pelewensis roosted on rugged and fairly inaccessible limestone islands near the centre of the archipelago, near where most people also lived. We were unable to estimate population size or determine population trend in the island chain. The bats are heavily harvested for commercial export, with more than 180,000 animals shipped to the Mariana Islands from 1975–1994. Smaller numbers are also killed as a local food source. Emballonura s. palauensis , the only insectivorous bat in the islands, was seen at 65% of the evening count locations and was also widespread in the archipelago. Recommendations for managing bats in Palau include a prohibition on the export of fruit bats and the establishment of several protected areas.     

Reproductive biology and postnatal development in the tent-making bat Artibeus watsoni (Chiroptera: Phyllostomidae)

In this study we investigated the reproductive patterns and postnatal development in the tent-making bat Artibeus watsoni . We sampled two populations in the Golfito Wildlife Refuge and Corcovado National Park, south-western Costa Rica, from June 2003 to March 2005. Most females were pregnant during the months of January and June, and most were lactating in March and July, indicating that this species exhibits seasonal bimodal polyoestry, with the first parturition peak occurring in February–March and the second in June–July. Additionally, we observed a postpartum oestrus following the first parturition, but not after the second. Females entered oestrus again in November–December and had a gestation period of c . 3 months. A female-biased sex ratio of neonates was observed during the second parturition period, and young were born at 32 and 56% of their mothers' body mass and length of forearm, respectively. Adult proportions in length of forearm were attained faster than adult proportions in body mass, and sustained flight was only possible after 35 days of age, when pups had achieved 100 and 80% of adult length of forearm and body mass proportions, respectively. Weaning and roosting independence occurred when young were c . 30–40 days old, and young females appeared to remain close to their place of birth, at least for their first mating period, whereas adult males were never recaptured near their birth site. In addition, sexual maturity was reached in as little as 3 months in females born during the first parturition period, whereas females born during the second birth period in June–July seemed to reach maturity at 6 months of age. Our results show that A. watsoni belongs to the faster lane of the slow–fast continuum of life-history variation in bats, which may be attributed primarily to its roosting and feeding ecology.     

Development of echolocation and communication vocalizations in the big brown bat, <Emphasis Type="Italic">Eptesicus fuscus</Emphasis>

Big brown bats form large maternity colonies of up to 200 mothers and their pups. If pups are separated from their mothers, they can locate each other using vocalizations. The goal of this study was to systematically characterize the development of echolocation and communication calls from birth through adulthood to determine whether they develop from a common precursor at the same or different rates, or whether both types are present initially. Three females and their six pups were isolated from our captive breeding colony. We recorded vocal activity from postnatal day 1 to 35, both when the pups were isolated and when they were reunited with their mothers. At birth, pups exclusively emitted isolation calls, with a fundamental frequency range <20 kHz, and duration >30 ms. By the middle of week 1, different types of vocalizations began to emerge. Starting in week 2, pups in the presence of their mothers emitted sounds that resembled adult communication vocalizations, with a lower frequency range and longer durations than isolation calls or echolocation signals. During weeks 2 and 3, these vocalizations were extremely heterogeneous, suggesting that the pups went through a babbling stage before establishing a repertoire of stereotyped adult vocalizations around week 4. By week 4, vocalizations emitted when pups were alone were identical to adult echolocation signals. Echolocation and communication signals both appear to develop from the isolation call, diverging during week 2 and continuing to develop at different rates for several weeks until the adult vocal repertoire is established.     

Geophagy by the Indian short-nosed fruit bat, <Emphasis Type="Italic">Cynopterus sphinx</Emphasis> (Pteropodidae) while foraging on <Emphasis Type="Italic">Madhuca latifolia</Emphasis> (Sapotaceae) in Tamil Nadu,South India

Geophagy has been reported in many mammals and birds. However, in pteropodid bats, this behaviour has not been reported. Here, we document geophagy behaviour by the pteropodid bat, Cynopterus sphinx, during foraging in the fruiting trees of Madhuca latifolia (Sapotaceae). These bats removed single fruits from the foraging tree and carried it to the feeding roost for consumption. At around 1900 h, we observed three individuals of C. sphinx gleaning over the ground surface by circling flights. The bats landed with their wings spread apart and started licking the soil with head movements. Their ventral body surface rested completely on the ground while consuming the soil. A total of 91 feeding bouts of soil consumption were recorded within 1 h; however, thereafter, this behaviour was not observed. In order to understand the function of geophagy, we quantitatively analysed the composition of minerals in the soil, as well as in the M. latifolia fruits (partially ripe) along with its secondary metabolites from the study site. Our results revealed that the partially ripe fruits contained high levels of secondary metabolites (alkaloids, tannins, coumarins and saponins). The soil contained higher levels of Mg, Ca, Fe, Na and K minerals than the fruits. These findings suggest that bats may gain essential minerals that are low in their fruit diet by consuming soil. In addition, the observed minerals that play a role in detoxification of the secondary metabolites present in the partially ripe fruits that might be detrimental to the consuming bats. Frugivory, nectarivory and folivory are well understood in C. sphinx; however, geophagy behaviour has not been reported in this species so far. This may represent an ‘adaptive behavioural plasticity’ in the foraging behaviour of the observed C. sphinx population.     

Social Learning of a Novel Foraging Task by Big Brown Bats (Eptesicus fuscus)

Acquiring information via observation of others can be an efficient way to respond to changing situations or learn skills, particularly for inexperienced individuals. Many bat species are gregarious, yet few studies have investigated their capacity for learning from conspecifics. We tested whether big brown bats (Eptesicus fuscus) can learn a novel foraging task by interacting with knowledgeable conspecifics. In experimental trials 11 na?ve bats (7 juveniles, 4 adults) interacted freely with trained bats that were capturing tethered mealworms, while in control trials 11 na?ve bats (7 juveniles, 4 adults) flew with untrained bats. Na?ve bats were then assessed for their ability to capture tethered mealworms. While no bat in the control group learned the task, a significant number of experimental bats, including juveniles with little or no experience foraging, showed evidence of learning. Eighty-two per cent of experimental bats and 27% of control bats directed feeding buzzes (echolocation calls associated with prey capture) at the mealworm. Furthermore, seven experimental bats (64%) showed evidence of learning by attacking and/or capturing the mealworm, while no bat in the control group attacked or captured the prey. Analyses of high-speed stereo video recordings revealed increased interaction with demonstrators among bats attacking or capturing the mealworm. At the time they displayed evidence of learning, bats flew closer together during feeding buzzes than during other portions of trials. Our results demonstrate that social interaction with experienced bats, and listening to feeding buzzes in particular, may play an integral role in development of foraging skills in bats.     

Flying bats use serial sampling to locate odour sources

Olfactory tracking generally sacrifices speed for sensitivity, but some fast-moving animals appear surprisingly efficient at foraging by smell. Here, we analysed the olfactory tracking strategies of flying bats foraging for fruit. Fruit- and nectar-feeding bats use odour cues to find food despite the sensory challenges derived from fast flight speeds and echolocation. We trained Jamaican fruit-eating bats (Artibeus jamaicensis) to locate an odour reward and reconstructed their flight paths in three-dimensional space. Results confirmed that bats relied upon olfactory cues to locate a reward. Flight paths revealed a combination of odour- and memory-guided search strategies. During ‘inspection flights’, bats significantly reduced flight speeds and flew within approximately 6 cm of possible targets to evaluate the presence or absence of the odour cue. This behaviour combined with echolocation explains how bats maximize foraging efficiency while compensating for trade-offs associated with olfactory detection and locomotion.     

Ethanol ingestion affects flight performance and echolocation in Egyptian fruit bats

Ethanol, a potential toxin for vertebrates, is present in all fleshy fruits and its content increases as the fruit ripens. Previously, we found that the marginal value of food for Egyptian fruit bats, Rousettus aegyptiacus, decreases when its ethanol content exceeds 1%. Therefore, we hypothesized that, if ingested, food containing >1% ethanol is toxic to these bats, probably causing inebriation that will affect flight and echolocation skills. We tested this hypothesis by flying Egyptian fruit bats in an indoor corridor and found that after ingesting ethanol-rich food bats flew significantly slower than when fed ethanol-free food. Also, the ingestion of ethanol significantly affected several variables of the bats’ echolocation calls and behavior. We concluded that ethanol can be toxic to fruit bats; not only does it reduce the marginal value of food, but it also has negative physiological effects on their ability to fly competently and on their calling ability.     

A case of infant swapping by wild northern muriquis (<Emphasis Type="Italic">Brachyteles hypoxanthus</Emphasis>)

Allo-parenting has been observed in a variety of female primates, and typically infants are reunited with their biological mothers assuming that their mothers are alive. We observed an exception to this pattern when two wild northern muriquis (Brachyteles hypoxanthus) exchanged infants of different sexes and then reared their adopted infants through weaning. The process of this exchange began when the infants were 4 and 8 days old, respectively. The mother of a 4-day old female carried and nursed her own daughter and the 8-day old son of a second female. The exchange ended when the second mother was first observed carrying the wrong infant 1.5 days later. This observation raises questions about the age and mechanisms of mother–infant recognition in this species, and about assumptions of mother–infant relatedness based on behavioral observations alone.     

Postnatal development of morphological and vocal features in Asian particolored bat,Vespertilio sinensis

We studied the postnatal development of morphological and vocal features in a free-ranging population of the Asian particolored bat, Vespertilio sinensis. There were no significant differences in postnatal growth rates between males and females on the basis of morphological changes. Body mass and forearm length followed a linear pattern of growth until 28 days of age at mean growth rates of 0.38 g/day and 1.15 mm/day, respectively and thereafter increased slowly. The length of total epiphyseal gap of the fourth metacarpal–phalangeal joint initially showed a linear increase for up to 16 days, followed by a linear decrease until day 46 at a mean rate of 0.18 mm/day. When forearm length was used in combination with changes in total epiphyseal gap length, we derived reliable age estimation equations for the 1–46 day age range. Of the three nonlinear growth models (logistic, Gompertz, and von Bertalanffy), the von Bertalanffy and logistic equations provided the best fit to the empirical curves for body mass and forearm length, respectively. Studies of vocal development showed that infants could emit short calls as precursors of echolocation calls after birth. Isolation calls and precursors of echolocation calls were both characterized by multiple harmonics. We observed a systematic increase in the value of the starting frequency without a significant change in the terminal frequency over the 3 week period of development. In addition, the duration of isolation calls increased until day 4 and then decreased, whereas, the duration of precursors of echolocation calls decreased continuously to reach a stable level.