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Food habits of the Lesser grison Galictis cuja (Molina, 1782) in the Huasco coastal desert, Los Choros, northern Chile
(JOURNAL OF ARID ENVIRONMENTS, 2025-12) Zuleta-Ramos, C.; ZRau, JR.
The Lesser grison, Galictis cuja, is a carnivorous mammal widely distributed in South America. However, its conservation status and natural history are poorly understood throughout much of its range. In Chile, it is found in all regions of the country from deserts in the north to temperate rainforests in the south. This species is characterized as Rare in most of the habitats where it has been recorded. This study analyzed the diet of G. cuja in the Huasco coastal desert of the Coquimbo Region, northern Chile. Sixty-three fecal samples were collected in September 2010 (spring), which were then analyzed and categorized using keys and reference collections. Its diet was generalist, consisting of imago arthropods, larvae, and pupae, which represented 75 % of the prey consumed. Coleoptera of the family Tenebrionidae were the most frequently found trophic category in the diet. However, the Lesser grison also consumes wild rodents, which accounted for 25 % of its diet, with the Darwin leaf-eared mouse Phyllotis darwini (about 50 g) being the most frequent prey item. This suggests that their diet in this arid ecosystem is generalist, which could also be related to the resources available in a fluctuating environment.
Aridity Niche and Species Traits Mediate the Global Vulnerability of Passerine Birds
(GLOBAL CHANGE BIOLOGY, 2025-06) Petit, M.; Sayol, F.; Weideman, C.; Bertin, A.
Biodiversity is experiencing an unprecedented crisis, with intensifying global aridity representing a critical driver of species extinction. However, the extent to which species' preferences for specific aridity conditions and their tolerance to a range of aridity conditions influence their vulnerability remains poorly understood. Using data from 5558 passerine bird species, we examined how aridity niche affects current and projected extinction risks and whether these relationships are influenced by other ecological and life-history traits altering species persistence. Bayesian models revealed significant impacts of aridity niche position and breadth on both current and projected extinction risks, with these effects varying according to other species traits. Overall, aridity niche interacted with a wider range of traits for projected extinction risk than for current extinction risk, indicating a broader array of species requiring conservation attention in the future. Our results identified three key risk groups: (1) species preferring humid conditions, (2) species confined to arid zones with small clutch sizes, and (3) species with narrow aridity breadth and with low habitat breadth, short generation length, an omnivorous diet, and a full migrant strategy. By identifying passerine birds most at risk, our study offers critical insights for prioritizing conservation actions, guiding both geographic focus and the identification of species requiring more attention under the ongoing climate change.
Age-driven structural characteristics relate to epigeal arthropod communities in olive agroecosystems of the Atacama Desert
(AGRICULTURE ECOSYSTEMS & ENVIRONMENT, 2025-06-15) Wallberg, BN.; Pizarro-Araya, J.; Alfaro, FM.; Calderón, JE.; Loayza, AP.
Intensive agriculture has led to a significant global decline of biodiversity. However, agroecosystems like olive groves can serve as biodiversity refuges, especially in arid environments, by acting as resource islands that promote the persistence of multiple species, including arthropods. The structural complexity and productivity of olive groves typically increase with age, enhancing their ability to sustain high biodiversity. In this study, we examined how epigeal arthropod diversity patterns vary across olive orchards of different ages in the Huasco Valley of Chile's Atacama Desert. We hypothesized that older olive orchards, with greater structural complexity and productivity, would harbor higher arthropod abundance, diversity, and distinct community compositions than a younger olive orchard. To test this hypothesis, we sampled epigeal arthropods in three olive orchards of different ages (young, intermediate, and centennial) using pitfall traps and characterized each orchard's structure and productivity (NDVI). Our findings indicate that olive orchard age is related to arthropod composition and abundance but not diversity. Young and intermediate olive orchards had higher arthropod abundance, dominated by isopods and hymenopterans, while entomophthorans and mites predominated in the centennial orchard. Each orchard harbored a unique arthropod community, with NDVI being a key factor in the centennial orchard, dry weed biomass in intermediate orchards, and leaf litter in young groves. These results suggest that the structural characteristics associated with olive orchard age play a crucial role in shaping arthropod communities in arid environments, highlighting the importance of habitat management within agroecosystems for promoting biodiversity.
Exploring the Causes of Multicentury Hydroclimate Anomalies in the South American Altiplano with an Idealized Climate Modeling Experiment
(ATMOSPHERE, 2025-06-20) Jara, IA.; Astudillo, O.; Salinas, P.; Torrez-Rodríguez, L.; Lampe-Huenul, N.; Maldonado, A.
Paleoclimate records have long documented the existence of multicentury hydroclimate anomalies in the Altiplano of South America. However, the causes and mechanisms of these extended events are still unknown. Here, we present a climate modeling experiment that explores the oceanic drivers and atmospheric mechanisms conducive to long-term precipitation variability in the southern Altiplano (18-25 degrees S; 70-65 W; >3500 masl). We performed a series of 100-year-long idealized simulations using the Weather Research and Forecasting (WRF) model, configured to repeat annually the oceanic and atmospheric forcing leading to the exceptionally humid austral summers of 1983/1984 and 2011/2012. The aim of these cyclical experiments was to evaluate if these specific conditions can sustain a century-long pluvial event in the Altiplano. Unlike the annual forcing, long-term negative precipitation trends are observed in the simulations, suggesting that the drivers of 1983/1984 and 2011/2012 wet summers are unable to generate a century-scale pluvial event. Our results show that an intensification of the anticyclonic circulation along with cold surface air anomalies in the southwestern Atlantic progressively reinforce the lower and upper troposphere features that prevent moisture transport towards the Altiplano. Prolonged drying is also observed under persistent La Ni & ntilde;a conditions, which contradicts the well-known relationship between precipitation and ENSO at interannual timescales. Contrasting the hydroclimate responses between the Altiplano and the tropical Andes result from a sustained northward migration of the Atlantic trade winds, providing a useful analog for explaining the divergences in the Holocene records. This experiment suggests that the drivers of century-scale hydroclimate events in the Altiplano were more diverse than previously thought and shows how climate modeling can be used to test paleoclimate hypotheses, emphasizing the necessity of combining proxy data and numerical models to improve our understanding of past climates.
Isolation and Characterization of Polyunsaturated Fatty Acid-Rich Oil from Jumbo Squid (Dosidicus gigas) Viscera: Antioxidant Potential and Anticancer Activity on Colorectal Cancer Cells
(WASTE AND BIOMASS VALORIZATION, 2025-07) Quispe-Fuentes, I.; Valenzuela, P.; Roco, T.; Pérez-Won, M.; Espinoza, J.; Bernal, G.; Bernal, C.; Martinez, R.
The global impact of residues resulting from fishing processing has generated the need to develop sustainable processes, find additional potential of raw materials, and provide alternatives for their recovery of potentially valuable by-products. On the other hand, colorectal cancer (CRC) is the second leading cause of cancer death worldwide and needs novel and more effective treatments. In this study, we extracted and characterized oil from Jumbo squid hepatopancreas and evaluated its antioxidant potential and antiproliferative activity. The oil recovered from the Jumbo squid production process has characteristics that meet international standards. PUFA-rich oil from Jumbo squid hepatopancreas showed high concentrations of EPA/DHA (about 42% of the total fatty acids) and antioxidant potential. The antiproliferative activity evaluated on colorectal cancer cells, HCT116, showed activity against the tumor cells, representing the first evidence for a potential anticancer application. This research proposes a sustainable strategy for achieving a circular bioeconomy by recovering oil from jumbo squid viscera, offering alternatives for valorizing this bioproduct.