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In this study, we present a new method to compare the distribution of knowledge regarding the biodiversity of a taxa with the distribution of environments inhabited by that taxa, in order to identify the main geographical gaps in biodiversity knowledge. We compared the geographical distribution of studies describing freshwater fish assemblages in Argentina with the distribution of freshwater bodies, delimiting priority areas that require additional sampling effort in order to achieve a more balanced understanding of this taxa’s diversity throughout the country. Our results show a substantial geographical bias in the distribution of knowledge regarding freshwater fish assemblages in Argentina, with most of the studies concentrating on a few areas of the country. Many sectors appear as undersampled, and most of the country has been studied only recently, after many sites have undergone severe impact by anthropic activities. The absence of fish assemblages descriptions previous to habitat changes in these sites considerably limits our capacity to understand changes in biodiversity that anthropic habitat modifications might have generated or even the ones they are generating now. We show the areas of Argentina where freshwater fish diversity needs to be studied most urgently based on the distribution of freshwater habitats.

Anthropogenic activities have detrimental impacts on natural habitats and the species inhabiting them. In particular, habitat fragmentation has a profound effect on the dynamics and structure of natural populations and the species’ probability of persistence. In this study, we examined which factors determine the population structure of Ctenomys species (tuco-tucos) at a local scale, evaluating the effects of natural and anthropic barriers on population divergence. We sampled tuco-tucos at 28 localities and genotyped 231 individuals at 11 microsatellite loci. Additionally, we built six spatial layers that describe the landscape inhabited by tuco-tucos, to evaluate the effects of habitat traits in the movement of individuals. We applied Bayesian clustering methods to infer the population structure, and landscape genetic tools to understand how landscape traits affect this structure. We detected a high degree of population structure, even at a small spatial scale. Genetic structure seems to be influenced not only by current landscape configuration but also by their recent evolution. Altitude was the main contributing factor explaining this structure, with independent populations restricted to different sandy elevations in the region. However, anthropic activities were also shown to have had a significant effect on the differentiation among populations. The accelerated transformation process that the region is undergoing strongly conditions the dynamics of population differentiation in Ctenomys and reduces prospects of viability for the species. Our findings underscore the importance of incorporating variables that describe the temporal component of habitat changes in landscapes experiencing intense and recent transformation processes.

Leopardus geoffroyi is a small feline with a widespread distribution in a broad array of habitats. Here we investigate its evolutionary history to characterize the phylogeographical patterns that led to its present distribution using mitochondrial DNA from 72 individuals collected throughout its entire range. All haplotypes conformed to a monophyletic group, including two clades with a central/marginal disposition that is incongruent to the proposed subspecies. Spatial diffusion analysis showed the origin of the species within the oldest and more diverse central clade. A Bayesian Skyline Plot combined with a dispersal through time plot revealed two population increases at 190 000-170 000 and 45 000-35 000 years ago, the latter period accompanied by an increase in the dispersal rate. Species distribution models showed similar patterns between the present and Last Interglacial Period, and a reduction of high-probability areas during the Last Glacial Maximum (LGM). Molecular evidence confirms L. geoffroyi as a monotypic species whose origin is located in Central Argentina. The last glaciation had little effect on the pattern of distribution of the species: the population and range expansion that started before the LGM, although probably being halted, continued after the glaciation and resulted in the presence of this felid in the far south of Patagonia. Fil: Gomez Fernandez, Maria Jimena. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Fameli, Alberto Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Rojo Gómez, Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Pereira, Javier Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Mirol, Patricia Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina

Populations of vertebrates are built of individuals of different sex, age class or stage, which often affect distinctly the population dynamics. Such intrapopulation partitioning of vital rates needs to be identified to develop efficient conservation actions. Using DNA extracted from feces and feathers we combined DNA-tagging and mark–recapture analyses to evaluate sex-specific population dynamics of an endangered population of capercaillie (Tetrao urogallus; Phasianidae). We built encounter histories for 120 individuals in the mating seasons of 2009–2011, in a study area of about 424 km2. Minimum number of individuals per mating season and estimates of population size ranged 56–67 and 76–115, respectively. Estimates of population size were consistently lower in multiple-season, open-population models than in single-season closed-population models. The super-population in the study area was 149 individuals for the whole study period. Sex-ratio was notably male-biased. Probability of recapture p ranged 0.62–0.70, and was similar for males and females. Female apparent survival φ was lower than expected, and much lower than male apparent survival. It includes however movements in and out of the sampled population, thus comparison with previously reported values based on conventional tagging should be cautious. Females showed higher turnover, indicated by higher probability β of entering the sampled population, and higher number of entries from the super-population, Bgross. Realized population growth rate ʎ was > 1 for both females and males. The combination of non-intrusive DNA-tagging and the analytical framework of mark–recapture models provided inferences on population dynamics that would have been hardly feasible with conventional methods. Male-biased sex ratios, higher female turnover and seemingly low female apparent survival were our key findings. While the whole population needs continuous monitoring, we believe that adult females deserve priority attention in evaluation and design of conservation actions.

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Understanding the processes and patterns of local adaptation and migration involves an exhaustive knowledge of how landscape features and population distances shape the genetic variation at the geographical level. Ctenomys australis is an endangered subterranean rodent characterized by having a restricted geographic range immerse in a highly fragmented sand dune landscape in the Southeast of Buenos Aires province, Argentina. We use 13 microsatellite loci in a total of 194 individuals from 13 sampling sites to assess the dispersal patterns and population structure in the complete geographic range of this endemic species. Our analyses show that populations are highly structured with low rates of gene flow among them. Genetic differentiation among sampling sites was consistent with an isolation by distance pattern, however, an important fraction of the population differentiation was explained by natural barriers such as rivers and streams. Although the individuals were sampled at locations distanced from each other, we also use some landscape genetics approaches to evaluate the effects of landscape configuration on the genetic connectivity among populations. These analyses showed that the sand dune habitat availability (the most suitable habitat for the occupation of the species), was one of the main factors that explained the differentiation patterns of the different sampling sites located on both sides of the Quequen Salado River. Finally, habitat availability was directly associated with the width of the sand dune landscape in the Southeast of Buenos Aires province, finding the greatest genetic differentiation among the populations of the Northeast, where this landscape is narrower.

The Cantabrian capercaillie (Tetrao urogallus cantabricus) is an endangered subspecies of the Western capercaillie, endemic of northern Spain, inhabiting the south-western limit of the species range. Assessing genetic variability and the factors that determine it is crucial in order to develop an effective conservation strategy. In this work, non-invasive samples were collected in some of the best preserved areas inhabited by Cantabrian capercaillie. Nine microsatellite loci and a sex-specific marker were analysed. We included five zones, separated by valleys with different levels of habitat modifications. No evidence of genetic clustering was found which suggests that fragmentation and development in the area do not act as barriers to gene flow. Nonetheless, significant differences among sampling zones were encountered in terms of their allelic frequencies (global FST = 0.035, p = 0.001). Pairwise FST comparisons showed differences between all sampling zones included, except between the two ones located in the South (Degaña and Alto Sil). These findings, along with the results of individual based genetic differences, indicate that gene flow among sampling zones might be at least slightly compromised, except between the two zones located in the South. Despite this, the sampling zones seem to exchange migrants at a rate that prevents genetic differentiation to the point of creating clusters. Our results show that the capercaillies in the study area constitute a single interbreeding group, which is an important piece of information that provides support to better understand the dynamics of this endangered subspecies. Fil: Fameli, Alberto Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Morán Luis, María. Universidad de Oviedo; España Fil: Rodríguez Muñoz, Rolando. University of Exeter; Reino Unido Fil: Bañuelos, María José. Universidad de Oviedo; España Fil: Quevedo, Mario. Universidad de Oviedo; España Fil: Mirol, Patricia Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina

Counting rare and elusive animals and evaluating their demographic status, are fundamental yet challenging aspects of population ecology and conservation biology. We set out to estimate population size (Nc), genetic effective population size (Ne gen), sex ratio, and movements based on genetic tagging for the threatened Cantabrian capercaillie. We used 9 microsatellite loci to genotype 134 droppings collected at 34 display areas during the breeding season. Using genetic capture-mark-recapture, we estimated 93 individuals (Nc, 95% CI: 70-116) in an area of about 500 km 2, with sex ratio biased towards males (1:1.6). Estimated N e gen (35.5) was 38% of Nc, notably higher than the published average in wild populations. This capercaillie population is small and well within concern in terms of population viability. By genetic tagging, we detected mostly short movements; just a few males were recaptured between contiguous display areas. Non-invasive surveys of endangered populations have a great potential, yet adequate sample size and location are key to obtain reliable information on conservation status. © 2014 Morán-Luis et al.