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The community-based mentorship program MPOWIR (Mentoring Physical Oceanography Women+ to Increase Retention) supports late-stage graduate students and early-career professionals who identify as women or non-binary genders. Its participants engage in mentorship training and professional development, facilitate group mentoring, and draw attention to barriers women and non-binary genders face in physical oceanography. MPOWIR was created to increase the retention of women in physical oceanography in early career stages but has unexpectedly benefited the MPOWIR community beyond graduate students and early career professionals. Senior leaders participating as mentors in MPOWIR report a renewed sense of purpose, new research collaborations, a chance to challenge their own biases, learning new ways to support mentees at their home institutions, awareness about career trajectories outside academia, and a stronger sense of community amid researchers who often felt isolated due to lack of diversity in their ranks. As they guide and inspire the next generation, mentors reflect on their own career struggles and advise on changes that will create a more equitable future for the discipline. This paper highlights the impacts of MPOWIR mentorship on senior leaders in physical oceanography and demonstrates that mentorship is a two-way exchange that energizes and inspires all participants to become active agents of change. It concludes with reflections on how institutions and organizations can facilitate effective mentoring and remove barriers to the professional development of senior leaders in mentoring roles.

Animal migrations occur in many taxa and are considered an adaptive response to spatial or temporal variations in resources. Human activities can influence the cost-benefit trade-offs of animal migrations, but evaluating the determinants of migration trajectory and movement rate in declining populations facing relatively low levels of human disturbance can provide new and valuable insights on the behavior of wildlife in natural environments. Here, we used an adapted version of path selection functions and quantified the effects of habitat type, topography, and weather, on 313 spring migrations by migratory caribou (Rangifer tarandus) in northern Québec, Canada, from 2011 to 2018. Our results showed that during spring migration, caribou selected tundra and avoided water bodies, forest, and higher elevation. Higher precipitation and deeper snow were linked to lower movement rates. Weather variables had a stronger effect on the migration trajectories and movement rates of females than males. Duration of caribou spring migration (mean of 48 days) and length (mean of 587 km) were similar in males and females, but females started (22 April) and ended (10 June) spring migrations ca. 6 days earlier than males. Caribou spring migration was influenced by habitat type, topography, and weather, but we also observed that caribou migrations were not spatially constrained. Better knowledge on where and when animals move between their winter and summer ranges can help inform management and land planning decisions. Our results could be used to model future migration trajectories and speed of caribou under different climate change scenarios.

Natural selection should favor development of behaviors that increase survival, including juvenile survival. Habitat characteristics (e.g., hiding cover, forage quality and availability), maternal habitat selection, and microhabitat selection by the calf may influence elk (Cervus canadensis) calf survival and recruitment. We assessed diurnal microhabitat selection of bed sites by elk calves and calf-rearing areas selected by adult females to determine if these characteristics were associated with calf survival. We radio-tagged 33 elk calves in west-central New Mexico in 2011 and 55 calves in north-central New Mexico in 2012. We tracked calves daily to locate calf bedding sites and collected data on selected physical features and vegetation characteristics at used and paired random sites. The paired differences in these characteristics were then associated with calf fate. At the calf selection scale, for every 1-m difference in the distance to nearest concealment cover, the odds that a site was from a surviving calf increased by 7.8%. Habitat selection by adult females also was associated with calf survival. The odds of a bed site being from a surviving calf increased by 1.9% for every 1% difference in percentage of grass cover. High levels of concealment cover at the bed site were related to calf survival status. When we expanded selection to the adult level, females with surviving calves selected areas with higher grass cover, suggesting adult selection for higher forage availability while still providing high concealment cover for the calf. La selección natural debería favorecer el desarrollo de comportamientos que aumenten la supervivencia, incluida la supervivencia de los juveniles. La supervivencia y el reclutamiento de las crías de uapitíes (Cervus canadensis) pueden verse influenciados por las características del hábitat (i.e. cobertura de protección, calidad y disponibilidad del forraje), la selección materna del hábitat y la selección del microhábitat por parte de la cría. Evaluamos la selección del microhábitat diurno de los echaderos por parte de las crías de uapitíes y las áreas de crianza seleccionadas por las hembras adultas para determinar si estas características estaban asociadas con la supervivencia de las crías. Colocamos 33 radiotransmisores a crías de uapitíes en el centro-oeste de Nuevo México en 2011 y a 55 crías en el centro-norte de Nuevo México en 2012. Rastreamos a las crías diariamente para ubicar sus echaderos y recolectamos datos sobre características físicas seleccionadas y de la vegetación en sitios pareados tanto usados como al azar. Las diferencias pareadas entre estas características se asociaron al destino de las crías. En la escala de selección por las crías, por cada m de diferencia en la distancia a la cobertura de protección más cercana, las probabilidades de que perteneciera a un ternero sobreviviente aumentaban en un 7.8%. La selección de hábitat por parte de hembras adultas también se asoció con la supervivencia de las crías. Las probabilidades de que un echadero fuera de una cría sobreviviente se incrementaron un 1.9% por cada 1% de diferencia en el porcentaje de cobertura de pastos. Los altos niveles de cobertura de protección en el sitio de los echaderos estuvieron relacionados con el estado de supervivencia de los terneros. Cuando la selección se amplió a los adultos, las hembras con crías sobrevivientes seleccionaron áreas con mayor cobertura de pasto, lo que sugiere una selección por adultos a una mayor disponibilidad de forraje y, al mismo tiempo, proporcionando una alta cobertura de protección para las crías.

Land managers interested in maintaining species diversity often face difficult decisions when managing cattle grazing. Choosing a successful stocking regime and intensity for a particular region can be difficult. Landowners in the southern Texas region face challenges identifying successful stocking regimes or grazing intensity because of high temperatures from April through October and frequent droughts that often last up to or longer than 3 years. Cattle grazing is a major southern Texas agricultural industry that can have profound impacts that alter the diversity and structure of vegetation. Small mammals are an appropriate focal group for understanding ecosystem changes because of their rapid reproductive cycles and successful use in monitoring ecosystem conditions. From 2015 to 2020, we conducted a small mammal mark–recapture study to understand the impacts of grazing, along with variability in temperature and rainfall, on small mammal abundance in southern Texas. Sampling occurred within four different cattle grazing treatments to provide insight on cattle interactions with small mammals. We analyzed changes in small mammal abundance between three groups based on their food preferences: omnivores, granivores, and herbivores. For all three groups, there was a negative influence of temperature, but not precipitation and year, on abundance. With landscapes changing with time, land managers could use these data as a baseline for monitoring small mammal abundance in this region and potentially other similar native rangelands. Los administradores de tierras interesados en mantener la diversidad de especies a menudo tienen que tomar decisiones difíciles con relación al manejo del pastoreo para ganado. La elección de la carga animal y la intensidad de uso para una región en particular pueden ser especialmente complejas. Los administradores de tierras de la región sur de Texas enfrentan desafíos identificando exitosos regímenes de carga animal o intensidad de pastoreo debido a las altas temperaturas de abril hasta octubre y las frecuentes sequías que a menudo duran hasta tres años o más. El pastoreo de ganado es una actividad agrícola de gran importancia en el sur de Texas que puede tener fuertes impactos que alteren la diversidad y estructura vegetal. Los pequeños mamíferos representan un adecuado grupo focal para el entendimiento de cambios a nivel ecosistémico debido a la rapidez de sus ciclos reproductivos y a que han sido utilizados de manera exitosa para monitorear el estado de salud de los ecosistemas. De 2015 a 2020, realizamos un estudio corto de captura y recaptura de pequeños mamíferos para entender los impactos del pastoreo, junto con la variación de la temperatura y la precipitación, en la abundancia de pequeños mamíferos en el sur de Texas. Muestreos se llevaron a cabo dentro de cuatro tratamientos diferentes de pastoreo de ganado para generar información acerca de las interacciones entre el ganado y los pequeños mamíferos. Se analizaron los cambios en la abundancia de tres grupos de pequeños mamíferos, basados en sus preferencias alimenticias: omnívoros, granívoros y herbívoros. La abundancia de los tres grupos varió con relación negativa a la temperatura, pero no en cuanto a la precipitación y el año. Ante cambios en el paisaje con el tiempo, estos datos pueden utilizarse como base para monitorear la abundancia de pequeños mamíferos en esta región y potencialmente en otros pastizales nativos similares.

The Large Treeshrew, Tupaia tana Raffles, 1821, is a small mammal (~205 g) from Southeast Asia with a complicated taxonomic history. Currently, 15 subspecies are recognized from Borneo, Sumatra, and smaller islands, and many were originally differentiated based on minor pelage differences and small sample sizes. We explored intraspecific variation in T. tana using quantitative osteological data obtained from the hands and skulls of museum specimens. Multivariate analyses reveal extensive overlap among T. tana populations in morphospace, indicating that the majority of currently recognized subspecies are not morphometrically distinct. In contrast, the separation between Bornean and Sumatran populations of T. tana is sufficient to recognize them as different subspecies. Comparisons of Bornean specimens to those on small, offshore islands reveal that the latter average smaller body size. This pattern is inconsistent with Foster’s island rule, which predicts that island populations of small mammals (< 5 kg) will average larger body size relative to mainland forms. A similar lack of support for ecogeographic rules has been noted in T. glis (Diard, 1820), suggesting that these “rules” are poor predictors of geographic variation in treeshrews.

Two new chlorinated bis-indole alkaloids, dionemycin (1) and 6-OMe-7′,7″-dichorochromopyrrolic acid (2), along with seven known analogs 3–9, were isolated from the deep-sea derived Streptomyces sp. SCSIO 11791. Their structures were elucidated by extensive HRESIMS, and 1D and 2D NMR data analysis. In vitro antibacterial and cytotoxic assays revealed that, compound 1, shows anti-staphylococcal activity with an MIC range of 1–2 μg/mL against six clinic strains of methicillin-resistant Staphylococcus aureus (MRSA) isolated from human and pig. Additionally, compound 1 displayed cytotoxic activity against human cancer cell lines NCI-H460, MDA-MB-231, HCT-116, HepG2, and noncancerous MCF10A with an IC50 range of 3.1–11.2 μM. Analysis of the structure-activity relationship reveals that the chlorine atom at C-6″ could be pivotal for conferring their bioactivities, thus providing hints on chemical modifications on bis-indole alkaloid scaffold in drug design.

Carrying capacity is 1 driver of wildlife population dynamics. Although in previous studies carrying capacity was considered to be a fixed entity, it may differ among locations due to environmental variation. The factors underlying variability in carrying capacity, however, have rarely been examined. Here, we investigated spatial heterogeneity in the carrying capacity of Japanese sika deer (Cervus nippon) from 2005 to 2014 in Yamanashi Prefecture, central Japan (mesh with grid cells of 5.5 x 4.6 km) by state-space modeling. Both carrying capacity and density dependence differed greatly among cells. Estimated carrying capacities ranged from 1.34 to 98.4 deer/km2. According to estimated population dynamics, grid cells with larger proportions of artificial grassland and deciduous forest were subject to lower density dependence and higher carrying capacity. We conclude that population dynamics of ungulates may vary spatially through spatial variation in carrying capacity and that the density level for controlling ungulate abundance should be based on the current density level relative to the carrying capacity for each area.