RESUMEN
Besides direct mortality, wind farms also affect aerial fauna by modifying their communities, reducing species diversity and richness through disturbance. During three consecutive years, we used mist nets and acoustic recorders, and conducted carcass searches, to characterize the assemblage of bat species and to estimate bat mortality at two nearby wind farms sited <5 km apart in a highly biodiverse region. We asked whether the diversity, richness and evenness of the assemblages varied yearly, predicting it would decrease through time. Richness and evenness did not change, but the diversity of species recorded acoustically, 96% being aerial insectivores, was significantly lower the third year. We estimate 4 - 15.7 fatalities/MW/year by wind farm, with 63% of species found as carcasses being aerial insectivores. We found >40% of dissimilarity in the species composition of bat assemblages between wind farms despite the short distance between them, with species turnover accounting for more than half of the dissimilarity every year. Similarly, species turnover accounted for >15% of the dissimilarity in the composition of the assemblage of live bats (captured and recorded acoustically) and the assemblage obtained through carcass searches. Our findings suggest that nearby wind farms impact bat communities differentially and aerial insectivores disproportionally. Long term, multi-method surveys are needed to characterize bat communities in highly diverse regions and to evaluate the post-construction effects that wind farms have on them.
Asunto(s)
Quirópteros , Animales , Fuentes Generadoras de Energía , Monitoreo del Ambiente , Viento , GranjasRESUMEN
Knowledge about the biodiversity of Baja California has been obtained mainly from natural protected areas (NPAs), while some unprotected natural areas have been poorly studied. The Sierra Cucapá in the northeast of the peninsula is one example. The objectives of this study are 1) to integrate existing knowledge of bird, mammal, and reptile diversity in Cucapá from public databases, citizen science platforms, and information generated from fieldwork, 2) to identify the spatial distribution of records in the study area, 3) to compare the composition of vertebrate species of Cucapá with that of NPAs of northern part of the peninsula, and 4) to assess the biological conservation value of Cucapá. We obtained records of 150 species of native vertebrates (102 birds, 34 mammals, and 14 reptiles) of which 10 species of birds, four mammals, and seven reptiles are included in a risk extinction category. The different sources of information contributed in a complementary way to the species inventories. Large areas in western and northern Cucapá lack records. The total difference in species composition between Cucapá and nearby NPAs ranged between 58 and 69% for birds, 61 and 79% for mammals, and 69 and 87% for reptiles. The species richness of Cucapá, its particular species composition, the presence of species in risk extinction categories, and the number and size of unexplored areas indicate that this area represents an opportunity for biological conservation in the northern part of the Peninsula. This work provides compelling data for the protection of Cucapá.
RESUMEN
The Selva Zoque region is characterized by a great variety of ecosystems for which there is little information about reptile species diversity and their conservation status. This study is the first assessment of the species richness, composition, and conservation status of reptiles of this region. Additionally, this information is compared with that of seven other tropical regions in northern Mesoamerica. In total, 141 native reptile species belonging to 81 genera and 29 families are recorded for the Selva Zoque region. Sixty species (42% of the total) recorded in Selva Zoque are in high-risk categories according to the Mexican Ministry of the Environment, the highest number for the Mexican regions of Mesoamerica. According to the IUCN, six species are in high-risk categories, seven species are in Data Deficient, and 23 (16%) have not been evaluated yet. According to the Environmental Vulnerability Scores approach, 28 species (20%) are in the high vulnerability category. The Selva Zoque species composition is most similar to Los Tuxtlas and Lacandona regions, and most dissimilar to Sian Ka´an Biosphere Reserve. The reptilian fauna of Selva Zoque has a distinctive composition, with the highest number (11 species) of endemic reptiles in the northern Mesoamerican, and species from two biogeographic provinces: the Gulf of Mexico and the Mexican Pacific Coast. These results indicate that the Selva Zoque is the most diverse region in native reptile species in northern Mesoamerica, highlighting it as extremely important for the conservation of the reptile fauna at local (southern Mexico) and regional levels (northern Mesoamerica).
RESUMEN
Resumen La composición de la dieta en anfibios puede ser influenciada por diversos factores que causan su variación intraespecífica, como pueden ser la distribución geográfica, ontogenia, estacionalidad, y el sexo de los organismos. El objetivo de este estudio fue analizar la composición de la dieta en adultos de la Craugastor rhodopis (rana hojarasquera común) en la región montañosa del centro de Veracruz, México. Un total de 77 individuos adultos fueron colectados durante la época de lluvias de 2012, de los cuales 66 tuvieron contenido estomacal. Se realizó un análisis de la variación intersexual en la diversidad de la dieta, y el volumen, número de presas, y número de categorías de presa consumidas. La dieta de C. rhodopis estuvo compuesta por 20 categorías, de las cuales predominó Orthoptera en cuanto a número, volumen, frecuencia de ocurrencia e importancia relativa. Los machos consumieron presas de menor tamaño en relación a las hembras. Aunque ambos sexos consumieron similar número de presas, se encontró un efecto significativo de la interacción del sexo y el tamaño de las ranas sobre esta variable de la dieta, en la cual las hembras pequeñas consumen más presas que las grandes, y los machos grandes consumen más presas que los pequeños. El alto consumo de ortópteros (al menos en cuanto a volumen) es un fenómeno común dentro de la familia Craugastoridae y posiblemente está relacionado con el éxito de algunas especies en los ecosistemas donde habitan. A pesar de que la composición de la dieta fue similar entre sexos en C. rhodopis, se sugiere que la competencia intersexual por los recursos tróficos es mínima, dadas las diferencias en el tamaño de presas consumidas por machos y hembras.(AU)
Abstract Dietary composition in amphibians may be influenced by several factors that cause their intraspecific variation, such as geographic distribution, ontogeny, seasonality, and sex of organisms. The objective of this study was to analyze the composition of the diet in adults of the Polymorphic Robber Frog Craugastor rhodopis in the mountainous region of central Veracruz, Mexico. A total of 77 adult individuals were collected during the rainy season of 2012, of which 66 had stomach contents. We performed an analysis of the intersexual variation in diet diversity, volume, number of prey, and number of prey categories consumed. The diet of C. rhodopis was composed by 20 categories. Orthoptera predominated in terms of number, volume, frequency of occurrence, and relative importance. Males consumed smaller prey items relative to females. Although both sexes consumed similar numbers of prey, we found a significant effect of interaction of sex and size of frogs on this variable, with small females consuming more prey than the large ones, whereas in males the opposite occurred. High consumption of orthopterans (at least in volume) is a common phenomenon within Craugastoridae and is possibly related to the success of some species in the ecosystems where they live. Although the composition of the diet was similar between sexes in C. rhodopis, we suggest that intersexual competition for trophic resources is minimal, given differences in prey size consumed by males and females.(AU)
