The characterization of bird traffic is a requirement for assessing the environmental impact of projects that create obstacles to bird movement (e.g., wind turbines, towers, and power transmission lines). For this purpose, the Chilean environmental authority recommends direct observation methodologies, i.e., the visual and/or auditory determination of the variables of interest by a team of observers in the field. These methodologies are subject to observer bias and sampling efforts, often determined by labor and economic factors. This raises the need to incorporate automated methodologies, such as radar, to achieve more precise characterizations. In this study, we compared six bird traffic variables (species, number, speed, direction, height, and flight length) obtained simultaneously by a group of observers and a maritime radar. The radar obtained significantly more records than the observers regarding the number of individuals, flight direction, and height. Speed and path length were recorded only by the radar, not by the observers. Species identification was the only variable where radar data did not allow identification, but observer experience did. These results indicate that bird traffic characterization, as currently implemented, is not providing accurate information for decision-making regarding the environmental viability of projects, and it would be advisable to progressively implement the use of radar in these environmental assessment studies.
Two recent records of the cinnamon red bat (Lasiurus varius Poeppig, 1835) are documented, in the Punta del & Aacute;rbol locality and Estrecho de Magallanes Park (EMP), both recorded during the austral spring in 2024 and 2025. In EMP, the individual remained roosting for approximately 24 consecutive days. Together, these records expand the knowledge of the distribution, ecology and possible survival strategies in southern environments, highlighting the need to expand the physiological and habitat studies in the Magallanes region.
The decapod crustaceans of the Cambaridae family are the most diverse on the American continent; In Mexico, a diversity of 56 species of the genus Procambarus is reported, however, the diversity and status of the habitat where these species are geographically distributed in the state of Veracruz, Mexico has not been updated, essential information for the sustainable management of their populations and habitat. The objective of the study was to describe the diversity, the municipalities with presence and the habitat status of species of the genus Procambarus for the state of Veracruz, Mexico. The geographical coordinates were classified based on the species reported, the number of records per species per municipality and population location maps were developed through Geographic Information Systems; the presence and characteristics of the habitat were verified through field monitoring. The landscape parameters (configuration and composition) were described from 10 land uses using buffers of 1 km radius; with an ANOVA and a Tukey test, landscape parameters were compared between species. This study reports 20 species and 2 subspecies, 4 species and 2 more subspecies of the genus Procambarus, which had not been reported previously. 22% of Veracruz municipalities have the presence of Procambarus species. The current state of the habitat of the Procambarus species is represented by an agroecosystem, with a low percentage of forest, a high percentage of cultivated area and a high diversity of landscapes, which generate threats to the populations and habitat of the species.
Xenopus laevis, one of the most successful invasive species worldwide, is distributed in Chile from the Atacama Region to the Maule Region, where it could compete with native amphibians and act as a vector for diseases. Here, we document for the first time the predation of Rhinella atacamensis egg clutches by X. laevis, which was confirmed through stomach content analysis. This record reveals a new threat to the reproduction and conservation of native Chilean amphibians.
Anuran amphibians use acoustic communication in breeding contexts, they are also the most threatened at the global level, with extreme declination rates. Thus, it is of particular interest to determine how the alteration of the sound environments by human intervention or anthropophonies affect them. Knowing the auditory sensitivity of animals is fundamental to assess the vulnerability of organisms to noises generated by anthropic activity. This study reviews and compares auditory thresholds of six species of native anurans measured in previous researches with simulations of machine noises at different distances from these sound sources. Measurements of auditory thresholds by means of electrophysiological techniques show that the auditory range of these vertebrates is between frequencies of 0.1 to 5 kHz, with two zones of higher sensitivity, below 0.5 kHz and between 1-2 kHz, corresponding to sound detection by the two auditory receptors of the anuran internal ear, the amphibian and basilar papilla, respectively. The lowest auditory thresholds for these two frequency ranges are 41-49 and 37-54 dB SPL, respectively, indicating that sound reception is impaired by machine noise in the high frequency range, corresponding to the spectral zone of the calls with which these anurans communicate, but low frequency range is also impaired. Simulation of acoustic barriers prevents in part noise interference of high frequencies, but is not effective to preserve low frequency reception. These evidences are relevant for further evaluations of the impact of anthropophonies in native species.
