Mauro I. Schiaffini

Distribution of Lyncodon patagonicus (Carnivora, Mustelidae): changes from the Last Glacial Maximum to the present

Abstract The Patagonian weasel (Lyncodon patagonicus) is one of the least known carnivores from South America, and excluding some contributions, knowledge of it seems anecdotal. It is supposed to inhabit herbaceous and arid environments of Argentina and Chile. Here we assess the potential distribution of the Patagonian weasel both during the present and the Last Glacial Maximum (LGM). We also integrate some of this information, providing a historical and geographic analysis (both through ecological niche modeling and biogeographic schemes) of the distribution of L. patagonicus. We found 2 major core areas of distribution, 1 in northwestern Argentina and another in southern Argentina (i.e., Patagonia). Patagonian weasel distribution seems to be primarily related to cold areas with marked temperature seasonality and elevations below 2,000 m above sea level. From LGM to the present, we observed a major retraction in potential distribution areas that might indicate the existence of a vicariance process affecting Patagonian weasel distribution. Resumen El Huroncito Patagónico (Lyncodon patagonicus) es uno de los carnívoros menos conocidos de Sudamérica, y excluyendo algunas contribuciones, su conocimiento parece anecdótico. Se supone que habita ambientes áridos con vegetación herbácea de Argentina y Chile. En el presente estudio evaluamos la distribución potencial del Huroncito Patagónico durante el presente y el Último Máximo Glacial (UMG). Para ello integramos información proveniente de análisis históricos y geográficos (Modelado de Nicho Ecológico y esquemas biogeográficos) de la distribución de L. patagonicus. De esta manera obtuvimos dos grandes áreas núcleo de distribución para la especie, una en el noroeste de Argentina y otra hacia el sur de Argentina (i.e., Patagonia). La distribución del Huroncito Patagónico parece estar relacionada en primer lugar con áreas frías de marcada estacionalidad térmica y altitudes por debajo de los 2000 m.s.n.m. El modelo generado indica que desde el UMG hasta el presente, hubo una mayor retracción en las áreas de distribución potencial, lo cual podría indicar la existencia de un proceso de vicarianza que afectó la distribución del Huroncito Patagónico.

Habitat use of the wild boar, Sus scrofa Linnaeus 1758, in Los Alerces National Park, Argentina

The aim of this work was to study the patterns of habitat use of the wild boar in Los Alerces National Park, Argentina. We surveyed 262 transects, totaling 26.2 km, searching for fresh signs of the species. The wild boar used low elevations more intensively (600 to 700 m asl) than higher elevations, and forests of Nothofagus dombeyi and N. antarctica with understory dominated by Chusquea culeou than other vegetation types. The occurrence of signs among elevation strips and vegetation types was different between summer and autumn. Our results might be helpful for park managers and park rangers in developing wild boar control plans.

Didelphimorphia and Rodentia (Mammalia) from Sierras de Tecka and surrounding areas, northwestern Chubut, Argentina

The small mammal fauna from northwestern Chubut Province (Argentina) is poorly known. We herein report small mammal assemblages from three new localities: Sierras de Tecka, an extra-Andean system elevated 900 m.a.sl.; Estancia La Mimosa on the Tecka river valley (at ca. 650 m.a.sl.); and Arroyo Pescado (at ca. 620 m.a.sl.) 40 km north of the other sites. Specimens were recovered from disaggregated owl pellets. Total species richness includes 16 native (13 sigmodontine and two caviomorph rodents, and one marsupial) and one introduced species. Estancia La Mimosa had the highest richness (n = 14), while Arroyo Pescado the lowest (n = 11). Four species were only recorded at Estancia La Mimosa ( Akodon iniscatus , Calomys musculinus , Oligoryzomys longicaudatus and Mus musculus ), two in Sierras de Tecka ( Notiomys edwardsii and Microcavia australis ) and one in Arroyo Pescado ( Geoxus valdivianus ). This work also adds new localities for Akodon iniscatus , Geoxus valdivianus , Lestodelphys halli and Notiomys edwardsii in western Chubut Province.