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The diet of Rufous-legged Owl, Strix rufipes,a small raptor present in an Andean protected area, is described here. During the fall of 2017, 44 pellets were collected in the study area, being subsequently analyzed. The occurrence of small mammal prey items in pellets was compared with capture frequencies with live-trapping through Sherman traps. Regarding occurrence frequencies in the diet, arthropods were the most frequent (49.34%), followed by mammals (39.31%), birds (7.86%) and reptiles (3.37%). However, in terms of biomass, mammals had the highest biomass contribution. The observed frequency of consumed preys showed a random pattern, according to the captures of small mammals obtained with Sherman traps. The role of wildfire in the composition of prey in the observed trophic spectrum of these forest owls is also discussed.

Background: The chilla or grey fox (Lycalopex griseus) is a native species from continental Chile and neighboring areas of Argentina. It was introduced to Isla Grande de Tierra del Fuego in 1951 and began to increase its abundance, to the chagrin of local sheep ranchers. Since 1998, its hunting has been authorized. Here we update information on the density, abundance, and activity of this fox in the Chilean sector of Tierra del Fuego Island, to evaluate its population trend since the last census conducted by the Servicio Agrícola y Ganadero (SAG) in 2007. Methods and results: We carried out two fox censuses on a 941-km transect on public roads, divided into eight routes, from October to November (spring) of 2021 and 2022, following the same design used by SAG for the fox assessments carried out from 1999 to 2007. We report a reduction of > 50% in the density and abundance of chilla foxes with respect to the 2007 estimate, which could be attributed to the interference by free-ranging dogs (Canis lupus familiaris), through restricting the use of space by the fox, while transmitting diseases and parasites, and to human hunting pressure and vehicle collisions. Discussion: The chilla fox decline highlights the need for an in-depth study to determine the ecological and socioeconomic impact of this exotic species on the ecosystems of Tierra del Fuego Island and the desirability of its management, if needed.

Background: A team of 3 scientometrists led by John Ioannidis published in 2020 an extensive and updated database (ca. 6.9 million researchers in 22 disciplines and 176 sub-disciplines), ordering them according to a composite bibliometric index that measures their whole trajectory (career-long) impact and their annual impact at year 2019. They reported the top 100,000 scientists (1.45% across all disciplinary fields) or the top 2% of each subfield discipline, thus publishing the ranking of ca. 150,000 researchers worldwide. Methods and findings: We filtered that information for the disciplinary and sub-disciplinary areas corresponding to Ecology and identified a total of 14 ecologists with residence in Chile that appear in either of those two worldwide rankings. We report their measured productivity as both whole trajectory (career-long) and as annual impact at year 2019. We attribute their high registered productivity to their training at the doctoral level in prestigious foreign universities, their academic positions in internationally recognized Chilean universities, and their participation in state-funded research centers of scientific excellence. Exceptions to the rule are presented. Conclusions: The 14 ecologists identified with the scientometric algorithm proposed by Ioannidis and coworkers include, but are not restricted, to the most cited ecologists in Chile. We put forth possible reasons for some puzzling omissions from these rankings.

We compared the consumption of rodent prey by barn owl Tyto albaand short-eared owl Asio flammeusduring winter in agricultural areas in southern Chile. Diets were studied on the basis of pellets collected during the winters of 1986, 1987 and 1996. Both owl species consumed a large number of different rodent prey (8–9 species), but they preyed more often on the olivaceus field mouse Abrothrix olivaceus(56% and 52% of all individual prey, respectively) and long-tailed pygmy rice rat Oligoryzomys longicandatus(12.6% and 18.6%, respectively). The diet of the two owl species largely overlapped (95%). The diet diversity of barn owls and short-eared owls was not statistically different and accordingly they showed a similar evenness in diet. The geometric mean weight of rodent prey (GMWP) for short-eared owls (33 ± 1.36 g) was significantly greater than that of barn owls (28.3 ± 1.81 g). No significant difference was found between the proportion of native and introduced rodent prey consumed by barn and short-eared owls. The high diet similarity between both owl species could be a result of convergencies in hunting modes and activity time, similar body mass, or homogeneous rodent prey distribution and abundance in the agricultural areas we studied. The higher GMWP for the short-eared owl was probably caused by the fact that it preyed on the largest rodent prey in our study sites, the Norwegian rat Rattus norvegicus. According to our rodent trapping in the field, barn and short-eared owls appear to be opportunistic rather than selective predators in agricultural areas in southern Chile.

Background: Ioannidis et al. (2020) reported a standardized estimate of scientific productivity obtained from a worldwide database of 6,880,389 scientists who published at least 5 papers picked up by the Scopus database, and elaborated a ranking of ca. 120,000 scientists by both whole trajectory (career-long) impact and their current impact at year 2019. The goal of our paper is to contextualize Latin American ecologists’ contribution at the world level based on the four most scientifically productive countries in the region. Methods and findings: Ioannidis et al. (2020) proposed a composite index that is the sum of six scientometric indicators: (1) The number of allocites, (2) the hindex, (3) a per capita corrected version of h, (4) the allocites received as single author, (5) those received as single + first author, and (6) those as single + first + last author. We selected data for ecologists from Argentina, Brazil, Chile, and Mexico and comparatively analyzed their productivity according to the proposed index. We also compared these data with those obtained from a global sample of the top ecologists worldwide. Conclusions: Based on Ioannidis et al.’s proposition to evaluate scientific productivity we extract three lessons: (1) It does not pay to publish many papers; what counts is the number of allocites (i.e.,self-citations do not add up). (2) Either be single, first, or last author; it does not pay to be in the middle of an authorship line. (3) Even worse it is to be among many co-authors because the proposed index allocates credits on a per capita basis.

Background: We determine the occurrence of self-citations among 36 Chilean ecologists with the highest hindex values recorded in Web of Science. Because the practice of self-citation is perceived as negative by inflating a given researcher’s impact factor, we evaluate if those ecologists (five of them having been awarded the National Prize in Natural Sciences) tend unduly to self-citation, or alternately, receive citations from others ostensibly because their peers recognize their theoretical and empirical output. Methods and findings: We use a recently proposed self-citation estimate easily calculated from hindex values recorded in the restricted-access Web of Science (Wos) database and the open-access Google Scholar’s (GS) Researcher Profiles and compare these metrics. Conclusions: The Chilean ecologists showed low self-citation values, independently of their status as National Prize awardees. Their publications were highly cited by unrelated peers, likely on account of their novelty or quality. Among middle-aged (50–60 year) and young (< 50 year) Chilean ecologists open-access GS hindex values are significantly correlated with those from WoS, thus rendering expeditious this method of citation assessment.

Small mammals were studied in two southern Chilean temperate rainforests in the precor-dillean Andes during 2 low-rainfall years following the 1982 El Niño event. Forests had somewhat different levels of canopy, shrub, and herbaceous cover, and species richness of trees but most of the same plants. Most captures were of four sigmodontine rodents, Akodon olivaceus, Abrothrix longipilis, Abrothrix sanborni, and Oligoryzomys longicaudatus; five other species and a putative hybrid were recorded. Maximum numbers were in January–July (late summer to winter) and lower numbers in August–December (late winter to early summer). All species had seasonal reproduction in September–April (spring to autumn). A. olivaceus and A. longipilis generally were long-lived, whereas survival rates were low for O. longicaudatus. Responses after the 1982 El Niño were small, and some populations increased during 1984. Populations of A. olivaceus fluctuated more than those of A. longipilis; those of A. sanborni were low and O. longicaudatus was sporadic and irruptive. Lower-elevational Chilean and precordilleran Argentine forests have similar species composition, but differences in demography and dominance of the former by more widespread, omnivorous A. olivaceus, animalivorous-fungivorous Abrothrix, and granivorous O. longicaudatus. Opportunities for immigration may explain greater homogeneity of populations of small mammals in Chilean rainforests relative to Argentine ones. Although responses to El Niño and subsequent droughts were weak, flowering episodes of bamboo (Chusquea) can have strong effects due to increased availability of food.