Between October 11 and 16, 2019, and March 12 and 14, 2022, nine flights were made along the coast of the province of Buenos Aires, Argentina, in meteorological conditions that allowed the sighting of several species of cetaceans. The two series of surveys (2019-2022) were carried out separately due to travel restrictions associated with the COVID-19 pandemic. We report the estimates of abundance for Franciscana dolphins (Pontoporia blainvillei). The number of sightings (and individuals) in 2019 and 2022 was 41 (68) and 55 (80), respectively. Abundance for FMA IVb was estimated to be 11 070, while for FMA IVc was 3309. The total abundance of Franciscana for both areas would give a figure of 14 379 dolphins. Considering this estimation obtained in 2022, plus the 5896 dolphins estimated in 2004 for the southern area, gives us a sum of 20 275 individuals without considering those in deeper waters beyond the 30 m isobath. Even though the comparisons with previous estimates (2003-2004) must be done cautiously, we did not detect a decreasing trend in the abundance of this species in the studied area. Considering an extrapolated abundance of 5894 individuals for the Bahía Samborombón (area not flown), Argentine waters would have a figure around 26169 individuals. This figure considers abundance only from the coast to the 30 m isobath. Considering this abundance, the mortality rates estimated to date for Argentine waters are less than the 2% established by the IWC as a risk to the population.
The analysis of δ13C and δ 15N values in collagen obtained from the Lama guanicoe modern and archaeological bones (N = 26) from the Sarmiento Basin area (Colhué Huapi and Musters Lakes, central Patagonia) indicates a diet based on C3 plants (Calvin–Benson photosynthetic carbon fixation cycle). Within this group of plants, a marked increase in grass consumption during the recent lapse (post–1 500 years BP) is recorded. In contrast, a strong signal of higher woody plant consumption is recorded between 3 844-1 920 years BP (i.e., shrubs) and among modern individuals (i.e., subshrubs). It is proposed that when the valley floors of the Colhué Huapi and Musters Lakes were exposed (post-1 500 years BP), there was greater availability of wetlands and grasslands.
The lowland tapir (Tapirus terrestris) is distributed throughout much of South America and is considered a keystone species because it fulfills crucial ecological roles in tropical forests. Tapirs are associated with forest ecosystems and water bodies throughout their geographic range. In the Orinoquia region of Colombia, tapirs are found in natural savannahs and in dense, gallery, and riparian forests. Although there is data available on tapir natural history, basic knowledge is still lacking across much of its distribution. This research generated a baseline of tapir distribution to assess habitat use and conservation areas across the Orinoquia. We built a database of 110 individual occurrences from camera trap sampling conducted in the departments of Arauca, Casanare, Vichada, and Meta. We built candidate models using the Wallace 2.1.3 R package and selected the best-performing models, which we then implemented in Maxent 3.4.4 to obtain the final distribution outputs. Precipitation seasonality and land cover were the most important variables for tapir distribution, and areas of dense gallery and riparian forests in good conservation state were found to be highly suitable habitats, especially in Arauca and Vichada. Tapir populations likely became locally extinct in the southern part of the department of Casanare. Our results constitute the first approximation of the distribution of the lowland tapir for the Orinoquia region of Colombia. It is necessary to generate additional regional and local data to allow for a more precise evaluation of distribution in these heterogeneous landscapes. The findings of this study provide useful information for conservation strategies and highlight the need for further research to better understand the distribution and habitat use of the lowland tapir in this region.
Biological material stored in Natural History Collections (NHCs) represents a key source of datafor genetic studies, although specimen age (year of collection) and preservation methods may affect DNAintegrity. We investigated microsatellite genotyping success of DNA isolated from 265 soft (skin) and hard(bone) samples of pumaPuma concolorand Pampas foxLycalopex gymnocercusspecimens (collected between1905 and 2022) from Argentinean NHCs. Overall, 43.8% of the samples were successfully genotyped, with signiffcantly higher success for those collected after 1989 than up until the same year (62.8%vs.17.9%). When comparing sample types, skin exhibited a signiffcantly higher success rate than bone samples (51.8%vs. 37.8%). Limited to the Pampas fox, we found no signicant differences in DNA concentration between genotyped and non-genotyped samples, while a slight negative correlation was observed between DNA concentration and sample age. We report simple and efficient sampling protocols, which could be widely applied for future studies based on biological material from NHCs. The advantages of skin sampling are twofold: it is only minimally affecting specimen integrity, especially for medium- to large sized carnivore mammal species, and it offers a suitable source of DNA from specimens hosted within collections for less than 30 years. However, the bone sampling approach we propose may provide a more reliable source of DNA for older specimens
The brown-nosed coati (Nasua nasua) is a Procyonidae mesocarnivore commonly found coexisting with people in Brazilian urban forest fragments. Here, we aimed to assess the diet of brown-nosed coatis in two urban forest fragments of Campo Grande, MS: Parque Estadual do Prosa (PEP), a protected area, and Air Force Village (AFV), an urbanized area with physical barriers such as walls and fences. The diet was analyzed based on feces of brown-nosed coatis captured in wire traps during campaigns conducted from March to November 2018, January to April 2019, and March to June 2020 (only PEP), with 10 consecutive days per monthly campaign. Once captured, animals were sedated and identified, and fecal samples were collected and analyzed macrocospically and microscopically. In total, 190 coatis were sampled (including 115 females, 65 males, and 10 unidentified individuals), with some individuals being recaptured during the study period, and a total of 510 items were identified across both areas, with PEP showing 238 items (average of 2.4 items/fecal sample) and AFV showing 272 items (average of 3.8 items/fecal sample). In PEP, the diet of the coatis consisted mainly of invertebrates (57.6 %), with human-derived food residues (HDFR), such as paper and string, representing 7.1 % of the diet. In AFV, invertebrates dominated the diet (98.6 %), with HDFR comprising 12.9 % of the diet. Therefore, HDFR was present in the diet of brown-nosed coatis in both studied areas, with AFV showing nearly double the percentage compared to PEP. This study highlights that in urban environments, the diet of these animals can include HDFR, although their diet is still dominated by natural food resources. It remains to find out the impact that such intake of HDFR (nearly 3 % of the diet based on Po) can have on the health of N. nasua individuals inhabiting urban environments
La evaluación de la dieta de mesocarnívoros generalistas es esencial para comprender su papel ecológico y su capacidad de adaptación en ambientes heterogéneos. En este estudio se caracterizó la variación de la dieta de la zorra gris (Urocyon cinereoargenteus) a través del análisis y registro de heces en tres tipos de cobertura vegetal (bosque de encino, vegetación riparia y zona antropizada) en Santiago Ixtaltepec, Asunción Nochixtlán, Oaxaca, México, durante las temporadas climáticas de lluvias y sequía. Se colectaron y analizaron 247 heces, y se identificaron 14 componentes alimenticios agrupados en cinco categorías. La dieta estuvo dominada por frutos, con la mayor frecuencia de ocurrencia (59,52 %), particularmente Juniperus sp., seguida por insectos (31,57 %), principalmente ortópteros y coleópteros. Aves, mamíferos y quilópodos tuvieron un porcentaje de representación menor. Se registra por primera vez en Oaxaca el consumo de los frutos de Juniperus sp., Quercus sp., Prunus sp., larvas Phyllophaga sp. y del roedor Reithrodontomys sp. El índice de Shannon y la amplitud de nicho de Levins indicaron mayor diversidad y amplitud trófica en la temporada de lluvias que en la de sequía, lo que refleja la disponibilidad estacional de recursos. Los resultados evidencian la plasticidad trófica de U. cinereoargenteus y su papel en la dispersión de semillas y control de invertebrados, y resalta la importancia de conservar la heterogeneidad del paisaje para mantener la funcionalidad ecológica de la especie.
Interactions between Neotropical felids, such as pumas (Puma concolor), ocelots (Leopardus pardalis), margays (L. wiedii), and clouded tiger cats (L. pardinoides), vary depending on their territorial behaviors. These felids are threatened by habitat degradation from urban and agricultural expansion and industrial activities, resulting in declining populations and greater vulnerability to environmental stressors. This study used camera traps to investigate the interactions and activity patterns of these felids in the Cordillera del Cóndor of southern Ecuador. We used negative binomial generalized regression models to analyze anthropogenic stressors and land cover variation on felid presence in three adjoining study sites: two mining concessions and a wildlife refuge. Our results showed that puma presence negatively impacts margay presence. We also observed a difference in activity periods for pumas, who were more diurnal in one of the concessions and more nocturnal at the other two sites. Puma presence was positively influenced by distance from the mining operation and associated infrastructures, but not by distance from other anthropogenic features. Finally, the influence of mining-related activities was a more significant indicator of small cat presence than land cover or other environmental factors, but to varying degrees. These results indicate a need for further monitoring of anthropogenic activities, such as mining, on felid communities and provide an opportunity for collaboration with industry to reduce these impacts.
