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Chagas disease is caused by the infection of the parasite Trypanosoma cruzi (Chagas, 1909). Mexico is estimated to be among the countries with the highest rates of human infections. The southernmost region of the Baja California peninsula is home to the endemic, highly aggressive, and largest Triatominae vector, thus far described: Dipetalogaster maxima (Uhler 1894). Previous single-year studies have attempted to estimate the natural infection rate of T. cruzi in this species, none encompassing a multiyear sampling design nor a species-specific diagnostic tool. We report the infection rate based on more than 717 individuals examined via a PCR species-specific diagnosis. The infection rate of T. cruzi was of 4.4% (n = 5/112), 0.9% (n = 4/411), and 4.6% (n = 9/194) for 2016, 2017, and 2018, respectively, resulting in an infection rate of 2% across all sites and years (n = 18/717).

A nivel mundial se ha documentado que la operación de parques eólicos genera impactos negativos en las aves. Estos impactos incluyen la mortalidad de las aves por colisión con los aerogeneradores, el desplazamiento de especies por modificación del hábitat, el efecto barrera y la pérdida de hábitat. Sin embargo, en México es escasa la información publicada sobre estos efectos negativos. En este estudio reportamos la mortalidad incidental de tres especies de aves paseriformes (pinzón mexicano, Haemorhous mexicanus; vireo gorjeador, Vireo gilvus, y chivirín saltaroca, Salpinctes obsoletus), en un parque eólico en La Rumorosa, Baja California, México. Los ejemplares de estas especies fueron localizados durante un programa de monitoreo de mortalidad de vida silvestre entre agosto de 2015 y agosto de 2016. El análisis post mortem de dos de los especímenes encontrados, permitió determinar que la causa de la mortalidad de los individuos se asoció a la colisión con los aerogeneradores. Estos hallazgos constituyen los primeros reportes documentados de mor­talidad de aves paseriformes en parques eólicos de México

Monitoring wildlife in geographical areas is essential for the conservation of the biological heritage. At present, the strenuous task of animal observation on-site has been mitigated with the use of camera traps. The information gathered by these devices comprises a sequence of images, which are triggered by motion or heat, and enables the monitoring of several geographical areas at the same time without perturbing the fauna. Notwithstanding the advances of these kind of monitoring approaches, the captured images still must be manually classified, becoming into an expensive process. This paper describes an automatic methodology for labeling images captured with camera traps as a support tool for animal behaviour analysis. Specifically, we focus on the analysis of the Ovis canadensis better known as desert bighorn sheep, a species that inhabits in northwestern Mexico, USA and Canada. The importance of this species lies in that it is an emblematic one, of great historical, cultural and social value. We adopted a methodology based on a residual neural network (ResNet) as feature extractor and standard models for the classification of images depicting species of interest. The method is built (trained) and evaluated on realistic images captured by camera traps in the field. We achieve classification performances ranging from 89% for a multiclass classification setting (7 classes associated to the animal of interest) to 99% in a binary classification scenario (presence vs. absence of the species). The collected data set, model and extracted features are publicly available under request. We foresee the released data set and the proposed solution will boost research on the analysis of this species.

Bat acoustic libraries are important tools that assemble echolocation calls to allow the comparison and discrimination to confirm species identifications. The Sonozotz project represents the first nation‐wide library of bat echolocation calls for a megadiverse country. It was assembled following a standardized recording protocol that aimed to cover different recording habitats, recording techniques, and call variation inherent to individuals. The Sonozotz project included 69 species of echolocating bats, a high species richness that represents 50% of bat species found in the country. We include recommendations on how the database can be used and how the sampling methods can be potentially replicated in countries with similar environmental and geographic conditions. To our knowledge, this represents the most exhaustive effort to date to document and compile the diversity of bat echolocation calls for a megadiverse country. This database will be useful to address a range of ecological questions including the effects of anthropogenic activities on bat communities through the analysis of bat sound., The Sonozotz project represents the first nation‐wide library of bat echolocation calls for a megadiverse country.

We provide a record and field observations of California vole (Microtus californicus) based on a specimen collected on 5 June 2013 in riparian habitat from Arroyo San Rafael, northwestern Sierra San Pedro Martir, Baja California, Mexico. The last known record of this species in Mexico was in 1974. This species was suspected to be extirpated from Mexico; however, our recent record confirms its present occurrence in this country.

We provide information on recent records of the 2 subspecies of striped skunk occurring in the north- eastern (Mephitis mephitis estor) and northwestern (M. m. holzneri) region of Baja California, Mexico. Most of the recent records for these subspecies come from valleys and suburban zones.

We report the southernmost records of the spotted skunk (Spilogale gracilis) and the ring-tailed cat (Bassariscus astutus) for the state of Baja California, Mexico. We also report the first specimens of the California chipmunk (Neotamias obscurus meridionalis) for the Central Desert of Baja California.

El área del Delta del Río Colorado es reconocida como región terrestre prioritaria que incluye áreas de gran importancia ecológica como la Reserva de la Biósfera Alto Golfo de California y Delta del Río Colorado. A pesar de su valor biológico, el conocimiento existente sobre grupos específicos como los quirópteros es escaso. Por tal motivo, el presente estudio tiene como objetivo elaborar el primer catálogo de los murciélagos de esta región, mismo que incrementará y actualizará el estado de conocimiento sobre este grupo de mamíferos. Para su elaboración se recopilaron 34 registros de especímenes depositados en colecciones científicas y se complementó el listado mediante la recolecta en campo durante el verano del 2006 y 2010, empleando de manera combinada redes de niebla y detectores ultrasónicos (modelos Anabat II y SD1). Se recolectaron 118 especímenes y se identificaron 1,525 registros de llamadas de ecolocalización. Se registran nueve especies agrupadas en tres familias y ocho géneros. La especie Antrozous pallidus es registrada por primera vez en la Región del Delta del Río Colorado. Los resultados obtenidos corroboran la importancia del uso combinado de redes de niebla y detectores ultrasónicos para incrementar en calidad y cantidad la información de los inventarios de murciélagos.

En el presente trabajo se registra por primera vez una colonia del murciélago filostomido Leptonycteris curasoae para Baja California, México, que también constituye la segunda localidad en el estado donde se registra esta especie.

A specimen of an adult male of the southern grasshopper mouse Onychomys torridus was collected in Punta Choros, 25 km SE of Bahia de los Angeles, Baja California, Mexico. This record extends the species' distribution 330 km SE of the prior southernmost locality on the peninsula.

We documented a southern range extension and new specimens of western gray squirrel (Sciurus griseus anthonyi) for the state of Baja California, Mexico. The most recent specimen was collected in the town Catavina and represents the southernmost record for the species and subspecies. Repeated observations of individuals in this new location suggest the presence of a marginal population in Mediterranean chaparral-desert scrub transition vegetation. RESUMEN.—Documentamos la extension de ambito mas sureno y nuevos especimenes de a ardilla gris occidental (Sciurus griseus anthonyi) para el Estado de Baja California, Mexico. El especimen mas reciente fue recolectado en el poblado de Catavina y representa el registro mas sureno para la especie y subespecie. Observaciones repetidas de indi- viduos en esta ultima localidad surena sugiere la presencia de una poblacion marginal en vegetacion de transicion de chaparral mediterraneo-matorral desertico.