Prey Spectra of Jaguar (Panthera onca) and Puma (Puma concolor) in Tropical Forests of Mexico

At the Calakmul Biosphere Reserve in Campeche, Mexico, the prey spectra of sympatric jaguars (Panthera onca) and pumas (Puma concolor) were studied by examination of their scats. 10 vertebrate species were identified for jaguars and 7 for pumas, mainly mammals and some birds. Based on these diet analyses, we conclude that jaguars and pumas coexist at Calakmul by means of different food habits.     

Scale‐dependent effects of forest restoration on Neotropical fruit bats

Neotropical fruit bats (family Phyllostomidae) facilitate forest regeneration on degraded lands by dispersing shrub and tree seeds. Accordingly, if fruit bats can be attracted to restoration sites, seed dispersal could be enhanced. We surveyed bat communities at 10 sites in southern Costa Rica to evaluate whether restoration treatments attracted more fruit bats if trees were planted on degraded farmlands in plantations or island configurations versus natural regeneration. We also compared the relative influence of tree cover at local and landscape spatial scales on bat abundances. We captured 68% more fruit bat individuals in tree plantations as in controls, whereas tree island plots were intermediate. Bat activity also responded to landscape tree cover within a 200‐m radius of restoration plots, with greater abundance but lower species richness in deforested landscapes. Fruit bat captures in controls and tree island plots declined with increasing landscape tree cover, but captures in plantations were relatively constant. Individual species responded differentially to tree cover measured at different spatial scales. We attribute restoration effects primarily to habitat structure rather than food resources because no planted trees produced fruits regularly eaten by bats. The magnitude of tree planting effects on fruit bats was less than previous studies have found for frugivorous birds, suggesting that bats may play a particularly important role in dispersing seeds in heavily deforested and naturally regenerating areas. Nonetheless, our results show that larger tree plantations in more intact landscapes are more likely to attract diverse fruit bats, potentially enhancing seed dispersal.     

Exploring population genetic structure in three species of Lesser Antillean bats

We explore population genetic structure in phyllostomid bats (Ardops nichollsi, Brachyphylla cavernarum and Artibeus jamaicensis) from the northern Lesser Antilles by investigating the degree to which island populations are genetically differentiated. Our hypothesis, that the island populations are genetically distinct because of a combination of founding events, limited migration and genetic drift exacerbated by catastrophe-induced fluctuations in population size, is derived from a priori hypotheses erected in the literature. The first prediction of this hypothesis, that within each species island populations are monophyletic, was tested using a parametric bootstrap approach. Island monophyly could not be rejected in Ardops nichollsi (P = 0.718), but could be rejected in B. cavernarum (P < 0.001) and Artibeus jamaicensis (P < 0.001). A second prediction, that molecular variance is partitioned among islands, was tested using an amova and was rejected in each species [Ardops nichollsi (P = 0.697); B. cavernarum (P = 0.598); Artibeus jamaicensis (P = 0.763)]. In B. cavernarum and Artibeus jamaicensis, the admixture in mitochondrial haplotypes from islands separated by > 100 km of ocean can be explained either by interisland migration or by incomplete lineage sorting of ancestral polymorphism in the source population. As an a posteriori test of lineage sorting, we used simulations of gene trees within a population tree to suggest that lineage sorting is an unlikely explanation for the observed pattern of nonmonophyly in Artibeus jamaicensis (PW < 0.01; PSE = 0.04), but cannot be rejected in B. cavernarum (PW = 0.81; PSE = 0.79). A conservative interpretation of the molecular data is that island populations of Artibeus jamaicensis, although isolated geographically, are not isolated genetically.     

Germination responses of four pioneer plant species after passage through the gut of a frugivorous Neotropical bat

Seed passage through the guts of bats potentially influences germination in different ways: physically, chemically and biologically. To evaluate the influence of a Neotropical bat on the seed germination of four pioneer plant species, an experiment was conducted. Considering the positive influence of bats on germination and the possibility of observing non-viability caused by microorganisms, we hypothesized that (i) seeds subjected to passage through bat guts without the influence of microorganisms have a higher germination potential. Considering the different ecological requirements for the germination of plant species, we also hypothesized that (ii) the four plant species present different germination parameters. The germination of seeds from feces and fruits in the presence and absence of microorganisms was compared for each plant species and among the four plant species. The ingestion of seeds by bats and the presence of microorganisms either improved or did not influence the germination parameters of plants, but the direction of the effects did not support the hypothesis in all cases. The germination parameters differed among most plant species except between Ficus adhatodifolia and F. guaranitica. Our findings indicate that the influence of bats on seeds depends on the microorganisms and singularities of plant species.     

Thermogenic capacity of three species of fruit-eating phyllostomid bats

This study evaluated the thermogenic capacity of three species of fruit-eating phyllostomid bats (Carollia perspicillata, Sturnira lilium and Artibeus lituratus) during the dry-cool and wet-warm seasons, by measuring changes in body mass, basal metabolic rate (BMR), maximal metabolic rate (MMR), nonshivering thermogenesis and shivering thermogenesis. Body mass was lower, on average, during the dry-cool season and all species of fruit-eating bats showed an increase in oxygen consumption after noradrenaline injection and after exposure to a He-O₂ atmosphere. However, the magnitude of this increase was similar in both seasons. BMR also did not vary between seasons. Although, our results showed for the first time that all three species studied were able to increase thermogenesis by both nonshivering and shivering thermogenesis, we did not find significant differences in any thermoregulatory variable measured when comparing data from the two different seasons. Probably the difference in the mean and variance of the temperature profile between seasons were not strong enough to alter the thermogenic capacity of these species. Furthermore, the use of alternative physiological (torpor) or behavioral (huddling) strategies might have alleviated the need to trigger energetic-costly thermogenic responses.     

Characterization of microsatellite loci in the Jamaican fruit‐eating bat Artibeus jamaicensis and cross‐species amplification

Artibeus jamaicensis is one of the most common bat species in the neotropics, with a well‐defined polygynous social structure in caves. In order to study behaviour and to examine patterns of paternity and relatedness between different harem groups, we developed 14 microsatellite loci from two different enriched genomic libraries. We screened 125 individuals from two different bat colonies and found that polymorphism ranged from five to 13 alleles. Heterozygosity ranged from 63 to 95%. The primers amplified across 14 bat species, indicating their potential utility for population‐level studies in several closely related bat species.     

Novel long-distance movements by Neotropical bats (Mammalia: Chiroptera: Phyllostomidae) evidenced by recaptures in southeastern Brazil

We report recapture data for phyllostomid bats in different types of forests, and at different altitudes, obtained through long-term fieldwork in southeastern Brazil. We provide evidence of long-distance movements, with bats moving up to 120 km from mountains to the beach, with an altitudinal variation of 1,237 m. These movements demonstrate the high mobility of these bats and represent the longest distances recorded for them so far in the Neotropics, besides reinforcing the need for long-term capture and recapture programs aimed at understanding the movement dynamics of bat populations.     

Population and Genetic Consequences of Hurricanes for Three Species of West Indian Phyllostomid Bats

Strong hurricanes can cause population reductions in West Indian birds and bats, but the genetic consequences of such reductions have not been documented. For three species of phyllostomid bats, we report on the genetic effects of three strong hurricanes that struck the northern West Indies in 2004. Hurricane Ivan devastated Grand Cayman and severely depressed populations of several bat species. Despite being smaller than pre-hurricane levels, the population of Artibeus jamaicensis (the only species we could resample) on Grand Cayman contained greater mitochondrial haplotype diversity but similar microsatellite allelic diversity compared to pre-Ivan levels. We suggest that hurricane-aided dispersal from Cayman Brac introduced two new haplotypes into the Grand Cayman population. In the Bahamas, two other phyllostomids ( Erophylla sezekorni and Macrotus waterhousii ) did not suffer population losses or changes in genetic diversity as a result of Hurricanes Frances and Jeanne. Our results suggest that strong hurricanes usually have greater demographic than genetic effects but that hurricane-aided dispersal can occasionally introduce new genotypes or haplotypes into island bat populations.     

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.