La bioacústica permite monitorear murciélagos difícilmente detectados con métodos tradicionales, como las redes de niebla, y permiten obtener información sobre diferentes aspectos de la biología de las especies de estudio. En los últimos años se ha incrementado el interés por la aplicación de estos métodos y, en consecuencia, ha sido rápido el desarrollo de los equipos de grabación ultrasónica y las herramientas de análisis. Sin embargo, en el Neotrópico la bioacústica de murciélagos está en etapa de crecimiento en algunos países y apenas ahora está apareciendo en otros, por lo cual es necesario fortalecer este campo para estudiar la alta diversidad taxonómica y funcional de la región. En este contexto, es indispensable contar con bibliotecas de señales acústicas, que sirvan como referencia para identificar, validar y comparar las grabaciones de diferentes especies y localidades. Algunos países del Neotrópico han avanzado en este proceso y están construyendo estas bibliotecas de referencia. En Colombia, el trabajo a futuro implica un reto, debido a las más de 200 especies de murciélagos presentes. Este trabajo presenta las bases metodológicas para tomar grabaciones de referencia de murciélagos en Colombia y generar una guía para aquellos que se están iniciando en este campo de investigación.

The immune response is affected by aridity, but it has been rarely examined in desert-dwelling bats. For two consecutive years, we examined the seasonal variation in the innate immune response of an insular desert bat, the fish-eating myotis (Myotis vivesi), in relation to its reproductive activity and ectoparasite load. We evaluated the reproductive activity based on external morphological traits and testosterone levels in the plasma for males and progesterone and estradiol for females. We injected phytohemagglutinin (PHA) into the footpads of the bats to estimate the innate cellular response, and we measured the bacterial killing ability (BKA) of the blood plasma to determine the innate humoral response. Both the external morphological traits and hormone levels indicate that the females were pregnant in spring and lactating in summer, and that the males were reproductively active in autumn, when mating probably occurred. The swelling response of the female and male bats was lower in spring. The BKA in the males did not vary seasonally; the BKA in the females varied seasonally but only in the first year of the study, with lower values in spring and summer. The BKA in spring was lower in the first year of the study, when the females appeared to be in early pregnancy, compared to the second year, when the females were in advanced pregnancy. The swelling increased as the body mass and body conditions of the males increased, but the BKA was not correlated with body mass or body condition in either sex. Ectoparasite abundance and prevalence did not vary among seasons. Ectoparasite abundance was not correlated with the PHA response in both sexes; it was not correlated with the BKA in females, but it was inversely correlated in males. Of the three hormones measured, only estradiol was correlated with the immune response: females with higher estradiol levels had a higher PHA response and BKA. Our findings indicate that the cellular and humoral innate immune responses of the fish-eating myotis varied throughout the year, following the seasonal reproductive pattern of the species. Our evaluation of the proximal factors affecting the expression of the immune response points to the potential immunoregulatory role of sex hormones and body mass.

Tropical dry forests are among the most threatened ecosystems worldwide. Bats' role in those ecosystems is critical because of multiple bat-mediated processes. Such processes are strongly related to bats' functional traits. However, it is poorly known which bat's functional traits could relate to variations in environmental conditions in tropical dry forests. In this study, we tested the hypotheses that bat functional traits would be significantly associated with landscape variables, climatic variables, and land-use intensity. For testing these hypotheses, we used data from phyllostomid and mormoopid bats captured in mist nets and data from non-phyllostomid insectivorous bat species registered by passive acoustic monitoring. We considered six functional traits for phyllostomid and mormoopid bats, and for non-phyllostomid insectivorous bats, we added two echolocation parameters. We measured five environmental variables, two of local climate (daily maximum temperature and wind speed) and three of landscape features (total area of water and closeness, probability of finding caves, and conservation status). The relationships between bat functional traits and environmental variables were evaluated using the RLQ and the fourth-corner analysis. We captured 360 individuals belonging to 14 species with mist nets (Phyllostomidae and Mormoopidae), and we identified 18 species and six sonotypes with acoustic sampling (Emballonuridae, Mormoopidae, Molossidae, Natalidae, Noctilionidae, and Vespertilionidae). We found that bats' functional traits related to environmental conditions were pulse structure, diet, vertical foraging stratification, and trophic level, although these relationships varied among bats' ecological roles. The hematophagous were related to water bodies' closeness, and animalivorous bats, mostly mormoopids, showed a relationship with the probability of finding caves. Insectivorous bats that mostly forage on the canopy and emit qCF calls were significantly related to more conserved sites, and bats that emit qCF pulses were significantly associated with less area covered by water. Our findings provide insights into how bat functional traits vary in their relationships with environmental conditions in harsh environments such as dry forests.

The edge effect is one of the consequences of forest fragmentation and is one of the main drivers of alteration of ecological and ecosystem processes. Trophic guilds and species of bats have shown differential responses to this phenomenon. Our goal was to describe the change in bat species richness, abundance, evenness, and species composition of trophic guilds associated with a matrix edge-forest interior gradient. Therefore, we conducted a bat sampling with 16 mist nets covering such gradient in four sub-andean forest fragments (10-50 ha). In total, we captured 566 individuals of 21 species of phyllostomid bats. Bat species richness and abundance were higher in the matrix and edge and were similar between fragments. Evenness showed the lowest values in the matrix and forest edge and was different between forest patches. Some shrub frugivorous bats were more abundant in the edge, and others were more abundant in two fragments. Species composition of canopy frugivorous bats was similar along the gradient but was significantly different between fragments. In contrast, the species composition of nectarivores was similar throughout the matrix-interior forest gradient and between patches. Our data suggest that bat responses at assemblage-level are affected by the disturbance gradient from the matrix to forest interior, even at short distances form fragment borders, and are dependent on the trophic guild.

Understanding the spatial distribution of animal species, which involves integrating species occurrence with environmental data, provides crucial information for conservation planning, especially for threatened species. In this study, we used niche-based species distribution models to create a potential distribution map of Leptonycteris curasoae, a vulnerable fruit- and nectar-feeding bat. This model incorporated occurrence data from field sampling, mammal collections, scientific literature, and environmental variables. Additionally, we mapped the threats faced by L. curasoae and overlaid this data with protected area boundaries to identify priority conservation regions. Our results indicate that the current and potential distribution of this species is considerably smaller (~9 %) than the area previously considered according to the IUCN Red List. The potential distribution of L. curasoae is environmentally restricted to arid and semiarid areas and dry forests in Aruba, Bonaire, Curaçao, Northern Colombia, and Venezuela, characterized by high temperatures, low precipitation, and seasonality in temperature and precipitation. Approximately 22 % of the suitable areas for this species are within protected areas, and we observe differences in the magnitude of the area under protection and the impact of identified threats among countries. Roost vandalism is the most critical threat in Curaçao and Venezuela, while mining, tourism, and wind farms are more frequent in Colombia. Expanding or creating protected areas and roosts, jointly with establishing conservation corridors and connected private reserves across political boundaries, are high-priority conservation actions needed to guarantee safe mating and maternity roosts, long-distance movements, and connectivity of L. curasoae populations along its entire geographic distribution.