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Three species of pocket mice (Chaetodipus artus , C. goldmani , and C. pernix) characterize the Sinaloan subregion of the Sonoran regional desert. They occur primarily in Sinaloan thornscrub and monsoon (dry deciduous) forest biotic communities, both of which have suffered from agricultural conversion. Sinaloan thornscrub occurs along the coastal plains of southern Sonora and Sinaloa, México, and grades into monsoon forest in the foothills of the Sierra Madre Occidental. We describe the geographical and ecological distributions of the 3 species of Chaetodipus , evaluate evolutionary relationships within each species based on mitochondrial DNA sequence data, and compare these to previously described phenetic, allozymic, and chromosomal variation. We elevate the subspecies of C. pernix to full species, delineate evolutionary units within C. goldmani and C. artus that we formally recognize as subspecies, and evaluate the conservation status of all 3 species of Chaetodipus. [ABSTRACT FROM AUTHOR]

Marijuana is the most prevalent illicit substance used globally. With increasing US legalizing recreational marijuana, more evidence is vital to minimize potential health risks. This study was conducted to test several hypotheses regarding postmortem THC/COOH‐THC in decedents before and after legalization of recreational marijuana in Nevada. We also compared presence of THC/COOH‐THC in decedents with respect to manner of death as recorded by the Clark County Office of the Coroner/Medical Examiner. THC/COOH‐THC concentrations for years 2015–2016 (pre‐legalization) and 2017–2019 (post‐legalization) were compared through an independent samples t‐test and chi‐square tests. A binary logistic regression was used to compare the presence of THC/COOH‐THC with covariates: age, gender, race, and manner of death. The average concentration of THC/COOH‐THC detected per decedent did not significantly differ before and after recreational legalization, whereas the proportion of decedents testing positive for THC showed a small but significant increase following legalization although no significant change in COOH‐THC was detected. The likelihood of testing positive for THC/COOH‐THC decreased as age increased. Sex, race, and manner of death were all associated with the relative risk of presence of THC/COOH‐THC in toxicology reports. An increase in proportion of users but not in concentration of THC/COOH‐THC was observed after legalization. The results are generally consistent with national reports and suggest toxicology data from decedents is a valuable method for surveying marijuana use by the general public. The early adoption of recreational marijuana by neighboring states may have precluded any major changes in use following legalization in Nevada. [ABSTRACT FROM AUTHOR]

Spotted skunks in Texas, U.S.A., showed preference to areas with large mesquite trees as habitat unlike striped skunks which apparently did not have preference for any specific habitats for foraging. Both varieties did not favor agricultural habitat.

The Atlantic horseshoe crab (Limulus polyphemus) is a common marine aquarium species and model organism for research. There is potential monetary and conservation value in developing a stable captive population of horseshoe crabs, however, one major impediment to achieving captivity is a lack of knowledge regarding captive diseases. We utilized 16S rRNA gene amplicon sequencing to track changes in the microbiomes of four body locations in three wild-caught (tracked over 14 months in captivity) and three tank-acclimated (>2 years in captivity) adult L. polyphemus in a touch tank at Shark Reef Aquarium at Mandalay Bay in Las Vegas, NV. The wild population hosted diverse and distinct microbiomes on the carapace (260 ± 96 amplicon sequence variants or ASVs), cloaca (345 ± 77 ASVs), gills (309 ± 36 ASVs), and oral cavity (359 ± 37 ASVs), which were dominated by classes Gammaproteobacteria , Bacteroidia , and Alphaproteobacteria. A rapid decline in richness across all body locations was observed within 1 month of captivity, with tank-acclimated (>2 years) animals having <5% of the initial microbiome richness and a nearly completely restructured microbial community. Tank-acclimated horseshoe crabs possessed distinct microbiomes that were highly uneven and low in species richness on the carapace (31 ± 7 ASVs), cloaca (53 ± 19 ASVs), gills (17 ± 2 ASVs), and oral cavity (31 ± 13 ASVs). The carapace, oral cavity, and gills of the tank-acclimated animals hosted abundant populations of Aeromonas (>60%) and Pseudomonas (>20%), both of which are known opportunistic pathogens of aquatic animals and can express chitinases, providing a plausible mechanism for the development of the carapace lesion pathology observed in this and other studies. The cloaca of the tank-acclimated animals was slightly more diverse than the other body locations with Aeromonas , Enterococcus , Shewanella , and Vagococcus dominating the community. These results provide an important baseline on the microbiomes of both wild and tank-acclimated horseshoe crabs and underscore the need to continue to investigate how native microbial populations may protect animals from pathogens. [ABSTRACT FROM AUTHOR]

The lower Colorado River has experienced extensive loss of riparian vegetation due to dams and other human activity. Sigmodon arizonae plenus (Colorado River cotton rat) is an isolated subspecies that only occurs along the lower Colorado River. The habitat and population demographics of S. a. plenus were quantified using a capture–mark–recapture technique. Permanent trapping grids were established at three sites with Colorado River cotton rats present, which included the Palo Verde Ecological Reserve, CA, Cibola Nature Trail, AZ, and Pintail Slough, AZ. Habitat was quantified horizontally and vertically within 1 m3 surrounding every trap station 4 times across 2 years. Individual recapture histories were used to model the survival, capture probability, and population size of Colorado River cotton rats over 5 trapping occasions spanning 4 years. Program Mark was used to model population demographic parameters using the Robust model. Population sizes (as estimated by capture–mark–recapture methods) were highly variable within and among the three sites. The Palo Verde Ecological Reserve population initially increased then decreased in size. The Cibola Nature Trail population began large and decreased overtime. At the beginning of the study, 20 individuals occupied Pintail Slough. No Colorado River cotton rats were captured at Pintail during the last occasion. We documented site differences in vegetation composition and cover; however, no statistical differences within site use were revealed. In general, the Palo Verde Ecological Reserve had the highest vertical cover estimates, followed by the Cibola Nature Trail and Pintail Slough. Reasonable estimates for demographic data were not possible for most occasions because of a steady drop in trap success throughout the study. The limitations of these data are discussed, along with their utility in restoration efforts. La parte baja del río Colorado ha experimentado una gran pérdida de vegetación ribereña debido a las represas y otras actividades humanas. Sigmodon arizonae plenus (rata de algodón del río Colorado) es una subespecie aislada que solo se encuentra a lo largo de la parte baja del río Colorado. El hábitat y demografía de la población de S. a. plenus se cuantificaron utilizando una técnica de captura–marca–recaptura a lo largo de la parte inferior del Río Colorado. Se establecieron trampas de captura permanentes en tres sitios. El hábitat se cuantificó horizontal y verticalmente dentro de 1 metro cúbico rodeando cada estación de trampa 4 veces a lo largo de 2 años. Se utilizaron historias de recaptura individuales para modelar la supervivencia, la probabilidad de captura y el tamanó de la población de ratas algodoneras del Río Colorado en cinco ocasiones de captura que abarcan 4 años. Se utilizó el Programa Mark para modelar los parámetros demográficos de población utilizando un modelo Robusto. Los tamaños de población (estimados por métodos de captura–marca–recaptura) fueron muy variables dentro y entre los tres sitios. La población de la Reserva Ecológica Palo Verde inicialmente aumentó y luego disminuyó en tamaño. La población de Cibola Nature Trail comenzó a crecer y disminuyó con el tiempo. Al inicio del estudio, 20 individuos ocuparon el sitio de Pintail. No se capturaron ratas algodoneras del Río Colorado en Pintail durante la última ocasión. Documentamos las diferencias del sitio en la composición y cobertura de la vegetación; sin embargo, no se revelaron diferencias estadísticas dentro del uso del sitio. En general, la Reserva Ecológica Palo Verde Ecological tuvo las estimaciones de cobertura vertical más altas, seguidas por Cibola Nature Trail y Pintail. Las estimaciones razonables de los datos demográficos no fueron posibles en la mayoría de las ocasiones debido a una caída constante en el éxito de las trampas a lo largo del estudio. Se discuten las limitaciones de estos datos, junto con su utilidad en los esfuerzos de restauración. [ABSTRACT FROM AUTHOR]

SNAPSHOT USA is a multicontributor, long-term camera trap survey designed to survey mammals across the United States. Participants are recruited through community networks and directly through a website application (https://www.snapshot-usa.org/). The growing Snapshot dataset is useful, for example, for tracking wildlife population responses to land use, land cover, and climate changes across spatial and temporal scales. Here we present the SNAPSHOT USA 2021 dataset, the third national camera trap survey across the US. Data were collected across 109 camera trap arrays and included 1711 camera sites. The total effort equaled 71,519 camera trap nights and resulted in 172,507 sequences of animal observations. Sampling effort varied among camera trap arrays, with a minimum of 126 camera trap nights, a maximum of 3355 nights, a median 546 nights, and a mean 656 ± 431 nights. This third dataset comprises 51 camera trap arrays that were surveyed during 2019, 2020, and 2021, along with 71 camera trap arrays that were surveyed in 2020 and 2021. All raw data and accompanying metadata are stored on Wildlife Insights (https://www.wildlifeinsights.org/), and are publicly available upon acceptance of the data papers. SNAPSHOT USA aims to sample multiple ecoregions in the United States with adequate representation of each ecoregion according to its relative size. Currently, the relative density of camera trap arrays varies by an order of magnitude for the various ecoregions (0.22-5.9 arrays per 100,000 km 2 ), emphasizing the need to increase sampling effort by further recruiting and retaining contributors. There are no copyright restrictions on these data. We request that authors cite this paper when using these data, or a subset of these data, for publication. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the US Government., (© 2024 The Ecological Society of America.)

Managing wildlife populations in the face of global change requires regular data on the abundance and distribution of wild animals, but acquiring these over appropriate spatial scales in a sustainable way has proven challenging. Here we present the data from Snapshot USA 2020, a second annual national mammal survey of the USA. This project involved 152 scientists setting camera traps in a standardized protocol at 1485 locations across 103 arrays in 43 states for a total of 52,710 trap-nights of survey effort. Most (58) of these arrays were also sampled during the same months (September and October) in 2019, providing a direct comparison of animal populations in 2 years that includes data from both during and before the COVID-19 pandemic. All data were managed by the eMammal system, with all species identifications checked by at least two reviewers. In total, we recorded 117,415 detections of 78 species of wild mammals, 9236 detections of at least 43 species of birds, 15,851 detections of six domestic animals and 23,825 detections of humans or their vehicles. Spatial differences across arrays explained more variation in the relative abundance than temporal variation across years for all 38 species modeled, although there are examples of significant site-level differences among years for many species. Temporal results show how species allocate their time and can be used to study species interactions, including between humans and wildlife. These data provide a snapshot of the mammal community of the USA for 2020 and will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, and the impacts of species interactions on daily activity patterns. There are no copyright restrictions, and please cite this paper when using these data, or a subset of these data, for publication., (© 2022 The Authors. Ecology © 2022 The Ecological Society of America.)