Deforestation is a critical threat to bats. The woolly false vampire bat Chrotopterus auritus is a carnivorous bat that is both an indicator species for well-conserved forests and a threatened species in Mexico and other countries due to deforestation. We currently lack the information needed to assess the effects of forest fragmentation and destruction on their populations and to develop plans for their conservation. We used GPS loggers to study the movement patterns of C. We observed 72 foraging nights by GPS-tagging 10 individuals from two colonies on 32 occasions in a highly disturbed heterogeneous landscape with extensive deforestation Hormiguero , and in a more homogeneous, well-preserved forested landscape Monterrey.
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Deforestation is a critical threat to bats. The woolly false vampire bat Chrotopterus auritus is a carnivorous bat that is both an indicator species for well-conserved forests and a threatened species in Mexico and other countries due to deforestation.
We currently lack the information needed to assess the effects of forest fragmentation and destruction on their populations and to develop plans for their conservation. We used GPS loggers to study the movement patterns of C. We observed 72 foraging nights by GPS-tagging 10 individuals from two colonies on 32 occasions in a highly disturbed heterogeneous landscape with extensive deforestation Hormiguero , and in a more homogeneous, well-preserved forested landscape Monterrey.
Tracked false vampire bats averaged a home range of The bats ranged farther and flew significantly longer distances in Hormiguero than in Monterrey, with males flying longer and more variable distances. They used the well-preserved semi-deciduous forest more often than secondary forest and agricultural fields for traveling and foraging, but the bats occasionally moved and hunted along the borders of secondary forest and agricultural fields adjacent to semi-deciduous conserved forest areas.
Although this carnivorous bat might cope with some fragmentation, we suggest that large well-preserved forested areas are highly important for its conservation. This is an open access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: All relevant data are within the manuscript and its Supporting Information files. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing interests: The authors have declared that no competing interests exist. The extraordinarily rapid rate of biodiversity loss marks the start of a sixth extinction event [ 1 , 2 ]. Despite some limited success of efforts to prevent extinctions [ 3 , 4 ], species extinction rates continue to increase [ 5 ] largely due to deforestation and habitat fragmentation [ 6 , 7 ].
While some species use fragmented or deforested habitats, others rely on large, well-preserved forested areas and are heavily affected by changes in environmental conditions and community composition caused by deforestation and fragmentation [ 8 — 10 ]. The conservation of these forest-dependent species requires understanding how different species use forested habitats.
Detailed information on the movements, home ranges, foraging areas, and habitat preferences of different species are necessary to identify conservation needs, and to predict the effect of deforestation and habitat loss on populations.
The carnivorous woolly false vampire bat Chrotopterus auritus has been considered an indicator species for well-preserved forests [ 9 , 11 , 12 ] although our knowledge of its behavior and ecology is limited. Although not yet globally endangered, deforestation is likely to threaten their populations in the future. Chrotopterus auritus is an opportunistic hunter that feeds mostly on small mammals, large insects, and birds, but it can also feed on fruits, pollen and reptiles and amphibians [ 18 — 26 ].
The restrictions on the diet of C. The relatively large body mass and short broad wings may cause this carnivorous bat species to hunt in cluttered areas, to have relatively small home ranges, and to move short distances from roost to hunting locations where they probably spend a considerable amount of time perched and listening for prey sounds [ 20 ]. Most of the reported captures of this species occur in extensive, well-preserved late-successional forests [ 9 , 11 , 27 — 33 ], but the bats do not completely avoid more fragmented, degraded forests and even secondary growth forest [ 34 — 37 ].
Gathering information on the movement ecology of C. Miniaturized GPS makes it possible to track the movement of bats with much greater precision and efficiency than radio-tracking [ 38 — 39 ].
We used GPS to track movements and habitat preference of C. We expected bats i to move and hunt mostly inside late-successional forests in an unfragmented, well-preserved landscape, but in a more fragmented landscape, we expected them ii to move and hunt in secondary forest, iii to avoid agricultural fields, iv to avoid low dry forest due to the low forest height and high tree density , and v to have larger home ranges and fly farther to hunting grounds in fragmented landscapes in comparison with the well-preserved late-successional forest site.
The climate in the study area is humid and warm with a mean annual temperature of The rainy season runs from June to October and the dry season from November to May. The predominant vegetation surrounding the two roosts was tropical semi-deciduous forest dominated by Brosimum alicastrum , Manilkara zapota , Metopium brownei , and Alseis yucatanensis trees.
These trees can reach up to 30 meters, but in our study areas they reached a maximum height of only 15 to 20 meters due to shallow soils causing low water availability [ 41 — 43 ] and hurricane disturbances [ 44 ]. Each of the two colonies of C. When we first equipped bats with GPS trackers, there were 8 individuals in the roost 2 adult females, 4 adult males, 1 juvenile female, and 1 juvenile male.
Land-use maps of the study areas were generated using a supervised classification technique on a SPOT-6 satellite image with four multispectral bands and a spatial resolution of 10 m. We rectified the land-use map using random ground control points and with field surveys where we traced the movement of the tagged C. For habitat selection analyses, we classified areas into medium semi-deciduous forest, dry low semi-deciduous forest, secondary forest, agricultural fields, savannah mixed woodland grassland , aguadas ponds , and areas of no vegetation cover.
The areas of no vegetation cover included areas where the topsoil layer was removed and the rock substrate was exposed limestone extraction , paved roads, and urban areas. The areas classified as secondary forest were areas of secondary woody growth after human or natural disturbances and were similar in structure and age 10—15 years old. As part of the forest management plan of the area of Hormiguero, land owners decided to abandon large areas of agricultural fields 10 years ago to reforest and conserve them.
We were unable to tag bats from the Monterrey roost during July and May Bats were captured inside their roosts using a butterfly net or 3 m x 2. For each bat, we determined sex, age, reproductive condition non-reproductive, enlarged testicles, pregnant, lactating, post-lactating , body mass using Pesola spring scales , and forearm length, and then clipped hair to uniquely mark individuals and to place GPS.
All of the GPS were programmed to get a spatial fix every 30 seconds. A fix is a GPS-based datum with information on the date, time, and quality signal strength and number of satellites used.
To study whether individuals hunt in groups, we attempted to tag as many of the bats from the same roost as possible after capturing. In Hormiguero, we obtained data from two individuals during the same nights in July, four individuals in September, three in December, four in February and four in May. In Monterrey, we obtained data during the same nights from three individuals in September, three in December and two in February. The GPS data were downloaded from the trackers once they were removed from the bats.
The individuals were not immediately re-equipped with GPS trackers after the removal of the GPS tracker; we waited at least 7 days before re-equipping bats with GPS trackers. The weight of the GPS trackers varied between 5. Previous studies [ 38 , 46 , 47 ] tested for an effect on the extra weight of the devices by comparing the body mass of bats when captured and equipped with trackers, to their mass when recaptured a few days later for device removal.
To assess if the GPS trackers negatively affected foraging, we also measured their body mass before placing the GPS trackers and after individuals were recaptured and trackers were removed. If the bats were negatively affected by the GPS trackers, we would expect to detect a decrease in mean body mass. We handled all bats following the guidelines for the use of wild mammals in research by the American Society of Mammalogists [ 48 ]. The Institute of Ecology approved the animal manipulation procedures before the start of the study.
The cave was situated on community property of the town of Centenario in the state of Campeche. The community issued the permission to study the bats in the cave. Although several methods are available to estimate the home range of animals [ 50 — 53 ], the use of minimum-linkage estimate cluster polygons seems the most fitting technique when it comes to mobile animals with relatively small foraging area [ 54 ].
This technique tends to overestimate home ranges, but using this method facilitates the comparison of habitat ranges among species because this method has been used by other recent studies evaluating movement of bats [ 39 , 55 — 59 ].
After plotting the locations from the GPS trackers, we distinguished locations that either followed a clear path from one location to another, or that formed a cluster in a relatively small area. We considered the latter to be areas where bats foraged, perhaps using a sit-and-wait strategy.
We estimated the core foraging area per individual by visualizing and manually selecting the locations that formed a cluster area of GPS locations and clearly did not form a path from one location to another. We estimated the maximum travel distance by calculating the straight distance from roost to the farthest fix. To account for effects of moon brightness and position, we created a moon index that was highest 5 when the moon was brightest and at a position of 90 degrees, and that was lowest 1 with a new moon or when the position of the moon did not reach above the horizon.
We defined an evening trip as starting when an individual left the roost and ending when it returned to the roost. When an interaction effect was not detected, we removed it and refit the model. Degrees of freedom and p-values were based on the Satterthwaite approximation for denominator degrees of freedom using the lmerTest package [ 60 — 61 ]. To define the available habitat for C. To investigate whether the habitats were randomly used by C. Briefly, we tested how the used habitat home range and core foraging area was related to the available habitat in the area.
The significance of habitat selection was tested using Wilks Lambda, and a ranked matrix was built to indicate which habitat was used significantly more or less than others permutations ; higher ranked habitats were of greater importance [ 62 — 64 ]. We provide R scripts as a supplement to reproduce all analyses in S1 File. The roosts were inhabited throughout the year by most of the same individuals and were rarely abandoned or only abandoned for a few days.
In this case individuals would move to another roost on the other side of the same Hormiguero temple. During the study, the colony in Hormiguero reached a total of eight individuals twice, but on both occasions, after 6—8 months, one or two individuals would be absent from the group.
The number of individuals in the Monterrey roost had a maximum number of seven C. We equipped 10 individuals with GPS on 32 occasions and obtained between 1 and 4 nights of movement data per individual, for a total of 17, fixes across 72 evening trips Table 1 , S1 Table. The movement of the tagged individuals are shown in Fig 1. The accuracy of the fixes depends on factors such as canopy openness, fix rate and the speed of the animal. The clusters of fixes shown in Fig 1 most likely represent perched individuals, using a sit-and-wait foraging strategy.
We identified a total of 30 clusters of fixes perching events during 19 nights of tracked data. Individuals spent an average of minutes perched each night. The average duration of a perching event was minutes and the mean number of perching events per night was 1. The short distances between clusters of fixes are most likely short flights between perches, while fixes with larger distances between them represent bats in flight.
The core foraging area and home range are shown in Fig 2 and Fig 3 respectively. The total recorded night flight paths of two females A and four males B in the study site of Hormiguero and two female C and two males D in the study site of Monterrey. Different colors depict different individuals. The core foraging ranges per night flight of two females A and four males B in the study site of Hormiguero and two female C and two males D in the study site of Monterrey.
The home ranges per night flight of two females A and four males B in the study site of Hormiguero and two female C and two males D in the study site of Monterrey.
The emergence times of bats were ambiguous since the GPS trackers were not always capable of getting a fix just after the bats left their roosts, but the earliest fix we observed was 29 minutes after sunset.
The average maximum flight distance traveled was 2. The average time outside the roost was 5 hours and 9 minutes. The longest night trip was 10 hours and 8 minutes and the shortest trip was 26 minutes. The home range averaged The core foraging area averaged 3. We never observed multiple tracked individuals visiting the same area at the same time.
The main habitat available in both areas was predominantly medium semi-deciduous forest, followed by secondary forest and low semi-deciduous forest in Hormiguero and also predominantly medium semi-deciduous forest followed by low semi-deciduous forest and savannah in Monterrey Table 3.
We did not observe the bats moving through low semi-deciduous forest or savannah.
Big-eared woolly bat
Designed by Paul Smith This website is copyrighted by law. Chrotopterus auritus W. This species is the sole representative of the genus Chrotopterus, Peters The origin of the name Chrotopterus is Greek meaning "skin wing" presumably in reference to the wing membranes. The species name auritus is Latin meaning "long-eared". Traditionally three subspecies have been recognised, that present in Paraguay is C.
Reproduction of Chrotopterus auritus Peters in captivity Chiroptera, Phyllostomidae. Correspondence to. Of more than 1, species of bats Hutson et al. Several aspects of biology are more easily observed in captivity, such as gestation, postnatal development and interbirth interval e.
The big-eared woolly bat or Peters's woolly false vampire bat Chrotopterus auritus is a species of bat , belonging to the Order Chiroptera and Family Phyllostomidae. The name Chrotopterus is derived from Greek roots ch ariots skin, color , and pteron wing. The epithet auritus refers to the large ears. Big-eared woolly bats are very large predatory bats, the second largest bat species in the neotropics. The length of the forearm ranges from There are only three New World phyllostomid bats of comparable size. They also possess two lower incisors, a trait typically shared with smaller bats.
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