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The common vampire bat, Desmodus rotundus Geoffroy, 1810, is a species with an extensive geographical distribution, occurring in a wide variety of habitats. A recent phylogeographical study using molecular markers described a scenario in which this species is formed by 5 distinct geographically circumscribed mitochondrial clades. Here we studied the craniometric variation of the common vampire bat to assess the amount of subdivision within this species and to test for the possibility of distinct morphological patterns associated with geographical lineages. We used 16 measurements from 1,581 complete skulls of adult D. rotundus representing 226 localities in South America and Mesoamerica. The assessment of morphological diversity between groups was done by the estimation of minimum FST values. Overall, the results show that most of the within-species variation is a result of the size component. Both shape data and size data are correlated with geographic distances. Our results favor the origin of biological diversity as the outcome of genetic drift and stepping-stone pattern of gene flow instead of local adaptations to local environmental conditions. The FST analyses also support male-biased dispersal. The results give little evidence to support previous suggestions that the common vampire bat may be composed of 2 or more species.

Ranchers have observed that residual hemorrhage decreases after livestock suffer repeated bites from common vampire bats (Desmodus rotundus). We hypothesized that repeated exposure to the anticoagulants in the bats' saliva generated an immune response. We compared clotting time of blood mixed with Desmodus saliva between individuals of several species of livestock that were regularly exposed to vampire bats (“bat-attacked”) and individuals living where bat predation was not observed (“bat-naive”). We also compared the bleeding times of domestic sheep following a single defensive bite from a bat, before and after subjecting the animals to a series of feeding bites by Desmodus. Clotting time was significantly shorter in bat-attacked than in bat-naive livestock. Bleeding time after a provoked defensive bat bite was significantly shorter after sheep were exposed to a series of feeding bites from Desmodus. Bat predation induced increased resistance by the prey against the anticoagulants, suggesting an...

We examined the host selection of common vampire bats (Desmodus rotundus) with stable carbon isotopes in an area that offered 2 isotopically contrasting food sources, either introduced livestock living on C4 plants or native rainforest mammals living on C3 plants. We predicted that vampire bats would have carbon isotope ratios (δ13C) similar to those of livestock if they select exclusively cattle. The δ13C of vampire bats averaged −10.3 ± 2.6‰ (mean ± SD) and was almost identical to that of livestock (X = −12.9 ± 1.6‰). Thus, both vampire bats and livestock are clearly members of the C4 food web. Typical rainforest mammals such as the fruit-eating bat Carollia perspicillata had a δ13C of −24.4 ± 0.6‰, which identified them as members of the C3 food web. The stable carbon isotope signature of local vampire bats implies a high degree of preference for cattle. We suggest that the population expansion of D. rotundus is only indirectly linked to increasing host densities and is more directly related ...

Procedures for transportation and maintenance of the white-winged vampire bat, Diaemus youngi , are documented for the first time. Contrary to previous reports, D. youngi has been maintained on a diet of defibrinated bovine blood supplemented weekly with fresh chicken blood. Gregarious by nature, D. youngi exhibits dominance-hierarchy behavior, and behavioral patterns unreported in other species of bats. Although primarily arboreal with regard to feeding behavior, D. youngi demonstrates the ability to feed terrestrially—a behavior documented for the first time. Observations of our captive colony contradict anecdotal and previously published information on feeding and behavior. Differences in feeding behavior between D. youngi and the common vampire bat, Desmodus rotundus , appear to be related to selection of prey (arboreal versus terrestrial prey, respectively). In places where these vampire bats coexist, resource partitioning may serve to reduce competition.

Twenty-seven taxa of bats from late Pleistocene fossils originated from five caves in Bahia, Brazil. In one cave, humeri of Mormoops megalophylla were dated radiometrically to 20,060 ± 290 years ago. In another cave, a cranium of Desmodus rotundus was found adhering to the underside of a coprolite of a sloth ( Nothrotherium ) that had a radiometric age of 12,200 ± 120 radiocarbon years ago. Among taxa represented by the fossils were one extinct species ( Desmodus draculae ), the first South American fossil records for Mimon bennettii, Furipterus horrens , and Tadarida brasiliensis , and the first Brazilian fossil records for M. megalophylla, Phyllostomus discolor, Diphylla ecaudata , and Nyctinomops macrotis . All caves but one occur within the semiarid Caatinga biome today. However, fossil occurrences of several species ( M. megalophylla, M. bennettii , and Eptesicus fuscus ), which today select moister habitats or humid caves, suggest that conditions in the area during part of the late Pleistocene were wetter than at present.

Secondary dentin and cementum were studied histologically in 17 known-age (2–8 years) specimens of Myotis lucifugus and M. velifer and in 30 adult specimens of unknown age representing Pteronotus parnellii, Leptonycteris nivalis, Artibeus jamaicensis, Sturnira ludovici , and Desmodus rotundus . Incremental lines in secondary dentin and cementum were highly variable (both between and within individuals) and did not correspond exactly to age although there generally was a loose correlation between number of lines and age. Difficulties in using such histologically recognizable characteristics to determine age are discussed and previous studies of age determination in bats are reviewed. Incremental lines in secondary dentin were associated with changes in direction and shape of dentinal tubules. Chemical and structural alterations in collagenous matrix and ground substance also were implicated in the formation of incremental lines. Incremental changes in cement were related to stress, consequent dental drift, and eruption.

Current ecological hypotheses suggest that annual reproductive patterns in tropical bats are related to rainfall such that individuals avoid weaning their young during the most stressful season of the year. The reproductive status of bats within well delineated populations from Caatingas and Cerrado biomes of Northeast Brazil were monitored over a 20-month period; seven species were captured in sufficient numbers to determine annual reproductive patterns with confidence. Noctilio leporinus exhibited seasonal monestry. Glossophaga soricina, Carollia perspicillata, Vampyrops lineatus, Artibeus jamaicensis , and A. lituratus exhibited seasonal bimodal polyestry. Desmodus rotundus exhibited asynchronous polyestry. Major differences were not detected between Caatingas and Cerrado populations of any species, even though the predictability and total amount of precipitation was different in the two biomes. Most species ( N. leporinus, V. lineatus, A. jamaicensis, A. lituratus, C. perspicillata ) wean their young primarily during the wet season, whereas G. soricina weans its first litter during the dry season and its second litter during the wet season.

Peru has one of the richest faunas of volant vertebrates of any country with over 1,680 species of birds (Parker et al., 1982) and 122 species of bats (Koopman, 1978). Herein we record six species of bats previously unknown from Peru. These, plus the two species reported new for the nation by Bowles et al. (1979) and the change in status of coastal Sturnira lilium (=Sturnira luisi, Davis, 1981), bring the total number of chiropteran species for Peru to 131. We provided information on the new records and noteworthy distributional and natural history observations on several other species of bats to augment reports by Tuttle (1970) and Koopman (1978). Selected measurements, taken from standard skin and skull specimens unless otherwise indicated, are recorded in millimeters (weights in grams) and include the following: greatest length of skull (GSL), condylobasal length (CBL), zygomatic breadth (ZB), length of forearm (including wrist, FA), and weight (WT). Skulls were extracted from some fluid preparations to verify identification. Specimens are housed in the Louisiana State University Museum of Zoology (LSUMZ) unless otherwise noted. Mormoops megalophylla Peters.-Our specimens (one male and four nulliparous females) were netted in June and October 1978, over a cattail-bordered water impoundment 12 km N Olmos (5?55'S, 79?47'W, elevation ca. 150 m) and a small pond 5.2 km N Olmos along the Pan American Highway in the department of Lambayeque. Although most of this arid coastal zone of northwestern Peru is overgrazed desert with scattered Acacia and Prosopis trees, orchards and large patches of Acacia forest occur in irrigated areas. Small ranges of rocky mountains are less than 10 km W. of the collecting sites. These specimens represent the first record of bats of this genus from Peru and extend the range of the species 600 km S from NW Ecuador (Smith, 1972). Mean (range) of selected measurements are: CBL, 15.2 (14.9-15.5); ZB, 9.8 (9.6-9.9); FA, 57.4 (56.7-58.3); and WT 16.6 (15.0-20.0). These agree with the measurements for M. m. carteri, a subspecies that is not sexually dimorphic (Smith, 1972). Other bat species taken at or near these localities include Pteronotus davyi, Phyllostomus discolor, Nyctinomops macrotis, Nyctinomops laticaudatus, and Eumops glaucinus. Glossophaga commissarisi Gardner.-The Texas Cooperative Wildlife Collection has a male collected October 1974 from Iquitos in the department of Loreto and a female collected August 1964 from 11 km SE Pucallpa in the department of Ucayali (formerly part of Loreto). The presence of Glossophaga commissarisi in Peru was expected since it had been reported from an island in the Amazon River 30 km NW Leticia in southern Colombia near the Peruvian border (Webster and Jones, 1983). Selected measurements for the male and female (GSL 20.3, 20.6; and FA, 35.1, 34.6) agree with those given by Webster and Jones (1983) for the Colombian specimens. The female was carrying an embryo with a crown-rump length of 12. Lonchophylla handleyi Hill.-Koopman (1978) considered this bat, then known as Lonchophylla robusta, to be an Amazonian lowland species because all Peruvian specimens had been collected below ca. 900 m. Two of our specimens, nulliparous females, were netted August 1977 with a Vampyrodes caraccioli at ca. 1,525 m in upper montane rainforest 3 km NE Abra Divisoria on the Tingo Maria-Pucallpa road (906'S, 75'47'W) in the department of Ucayali. A male (testes 7 by 6) was taken in October 1978 from the wall of a cave in upper montane rainforest ca. 10 trail km SE La Peca (5036'S, 78'17'W) at 1,325 m in the department of Amazonas. Other bats collected in this cave were Chrotopterus auritus (a male, the third locality record for Peru), Desmodus rotundus, and Diphylla ecaudata. Lonchophylla robusta Miller.-Hill (1981) recently studied the large, pale brown Peruvian and Ecuadorian members of this genus and assigned Peruvian specimens (formerly recognized as Lonchophylla robusta) to a new species, Lonchophylla handleyi. However, two of our specimens from the department of Amazonas agree with Hill's (1981) diagnosis of Lonchophylla robusta both in mensural characters and by the absence of a sparse fringe of hair along the posterior margin of the uropatagium. These specimens, a male collected 20 km SW Chiriaco on 16 December 1974 and a female taken 43 km (by road) NE Chiriaco 709 November 1984

The simple stomachs of Tadarida brasiliensis, Myotis velifer, and Antrozous pallidas are quite similar histologically, and contain gastric glands of the tubular variety seen in mammals generally. The stomach of Leptonycteris sanborni differs in being more saccular and in having tubular gastric glands that have few chief cells. The stomach of Desmodus rotundus was found to have an extremely long fundic or cardiac caecum, which contained acinar and tubuloacinar glands quite unlike gastric glands previously described in Mammalia.

MATTHEWS, L. H. 1941. Notes on the genitalia and reproduction of some African bats. Proc. Zool. Soc. London, Ser. B, 111: 289-346. MoHR, C. E. 1933. Observations on the young of cave-dwelling bats. J. Mamm., 14: 49-53. ORR, R. T. 1954. Natural history of the pallid bat, Antrozous pallidus (LeConte). Proc. Calif. Acad. Sci., 4th Ser., 28: 165-246. PEARSON, 0. P. 1947. The rate of metabolism of some small mammals. Ecology, 28: 127145. , M. KOFORD AND A. K. PEARSON. 1952. Reproduction of the lump-nosed bat (Corynorhinus rafinesquei) in California. J. Mamm., 33: 273-320. RAMAKRISHNA, P. A. 1950. Parturition in certain Indian bats. J. Mamm., 31: 274-278. REEDER, W. C. AND R. B. COWLES. 1951. Aspects of thermo-regulation in bats. J. Mamm., 32: 389-403. ROLLINAT, R. AND E. TROUESSART. 1896. Sur la reproduction des chauves-souris. M6m. Soc. Zool. de France, 9: 214-240. RYBERO, 0. 1947. Studies on bats and bat parasites. Svensk. Natur., Stockholm, xvi + 330 pp., 55 p1. SHERMAN, H. B. 1930. Birth of the young of Myotis austroriparius. J. Mamm., 11: 495-503. 1937. Breeding habits of the free-tailed bat. J. Mamm., 18: 176-187. STARCK, D. 1957. Ueber die Lange der Nabelschnur bei Siiugetieren. Ztsch. f. Saiugetierkunde, 22: 77-86. WHITAKER, A. 1905. Notes on the breeding habits of bats. Naturalist, Lond., 325-330. WnmSATT, W. A. 1945. Notes on the breeding behavior, pregnancy and parturition in some vespertilionid bats of the eastern United States. J. Mamm., 26: 23-33. . AND F. C. KALLEN. 1952. Anatomy and histophysiology of the penis of a vespertilionid bat, Myotis lucifugus lucifugus, with particular reference to its vascular organization. J. Morph., 90: 415-466. . AND H. TRAPIDO. 1952. Reproduction and the female reproductive cycle in the tropical American vampire bat, Desmodus rotundus murinus. Amer. J. Anat., 91: 415-446.

Observations are presented on the feeding capacities of captive vampire bats ( Desmodus rotundus ) and on their excretory functions as these relate to the volume of blood ingested and the metabolic efficiency of blood utilization. The average daily intake of blood by individual members of two large groups of bats in which consumption records were kept for a full year was 15.3 ml and 15.6 ml; the range of variation was between 11.6 and 21.0 ml. The daily consumption average of isolated individuals tended to be somewhat higher. One non-pregnant female maintained in isolation for 17 days consumed blood in excess of her body weight (28 gm ) on 13 of them, and on two days the amounts ingested were as high as 47 and 52 ml respectively. Urine excretion is copious, and generally amounts to slightly less than 50 per cent by volume of the blood ingested over a 24 hour period. Urine flow begins promptly after feeding, and evidence is presented that the tubular stomach is a major site of fluid absorption. Based upon observation of a single bat over a 4-day period it is estimated that the animal ingested (on a dry weight basis) an average of 0.12 gm solids/gm body weight per day, and “utilized” metabolically about 73% of the solids ingested. Justification is presented for our estimate (probably conservative), that under natural conditions a single vampire may ingest nearly two gallons of blood a year, and that the total blood lost by the animal prey of vampires in countries (such as Mexico) where the bats are common may amount to many hundreds of thousands of gallons annually.

Data derived from study of peripheral blood samples of adult captive vampire bats, Desmodus rotundus , are here presented in order to provide some standard values for the blood of this important species; these include total red and white cell counts, differential white cell count, hematocrit and hemoglobin values. The red cell values are high as in other bats, and the total white cell population is characteristically low, being only 30%, however, of the value previously reported for the vampire. Hematocrit and hemoglobin values are higher than in mammals generally (related to the high red cell value) but approximate values reported in other bat species.

Conditions and procedures which have been utilized in our laboratory in the successful maintenance of the common vampire bat, Desmodus rotundus , in captivity over a period of several years are described, with the expectation that they may prove useful to other investigators. Also described is a cage design which helps minimize some of the special problems associated with the handling of vampires and making provision for their sanitation; the cage can also be used to advantage with other species of bats.

During 5 netting nights, 99 vampire bats (Desmodus rotundus) (37 males, 57 females, five sex unrecorded) were taken in a mist net stretched before the entrance of a permanent cave roost in Tabasco. Each was banded; weight, sex, time of capture, and direction of passage (in or out of the roost) were noted; and the bat was then released. Because 33 individuals were recaptured one or more times, a total of 139 bats was handled. The repopulation of another roost during biweekly intervals following two successive removals of almost all bats present is recorded also. Analysis of these data suggest the following conclusions: 1) within a given population there may be multiple diurnal roosts among which individuals shift on a more or less daily and perhaps opportunistic basis (it has generally been assumed that vampires use a single home roost to which the same individuals return each day); 2) maximum foraging activity is restricted to the earlier hours of the evening; 3) vampires forage only after dark, the mean foraging time being estimated to be about 2 hours; 4) vampires seem not to utilize temporary nocturnal roosts in the usually Accepted sense, but return directly to a diurnal roost after foraging; 5) most individuals probably forage only once nightly; 6) heavy precipitation tends to suppress foraging activity; 7) differences in foraging pattern between the sexes were not apparent; 8) the amount of blood consumed may depend upon the length of the foraging period; 9) wild vampires probably consume not less than 20 per cent (of fasting body weight) more blood per diem than vampires in captivity, but variation from day to day apparently is great.