Andrés Muñoz-Pedreros

Comparative demography and diversity of small mammals in precordilleran temperate rainforests of Southern Chile

Small mammals were studied in two southern Chilean temperate rainforests in the precor-dillean Andes during 2 low-rainfall years following the 1982 El Nino 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 Nino 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 Nino and subsequent droughts were weak, flowering episodes of bamboo ( Chusquea ) can have strong effects due to increased availability of food.

HABITAT USE OF FOUR TERRESTRIAL CARNIVORES IN SOUTHERN CHILE

El proceso de transformacion del paisaje ha sido mas intenso y vasto en la depresion intermedia del centro y sur de Chile que en las zonas cordilleranas aledanas. En dicha depresion el bosque nativo original practicamente ha desaparecido y en el sur de Chile ha permanecido fragmentado e inserto en una matriz de agroecosistemas. Esto puede influir en la distribucion de los mamiferos carnivoros, segun sean especialistas o generalistas de habitat, asi como del tamano de su ambito de hogar. En este contexto el objetivo de este estudio fue evaluar, mediante el estudio de la distribucion de fecas, la seleccion de habitat del ensamble de carnivoros en un ambiente fragmentado en el sur de Chile. Documentamos el uso selectivo de Puma concolor, Galictis cuja y Lycalopex griseus de las plantaciones forestales exoticas con matorrales. Leopardus guigna, a pesar de no mostrar una seleccion estadisticamente significativa por el bosque nativo, presenta mayor numero de registros en dicho habitat. La seleccion de habitat de los depredadores estudiados muestra un grado variable de uso de los ambientes intervenidos y fragmentados. En las plantaciones forestales circundantes existe un sotobosque de vegetacion nativa que se adecua a los requerimientos de la mayoria de los carnivoros. Se discuten la superposicion espacial y la adecuacion a nuevos ambientes.

REPRODUCTION AND DEVELOPMENT OF Dromiciops gliroides (MARSUPIALIA: MICROBIOTHERIIDAE) IN TEMPERATE RAINFORESTS OF SOUTHERN CHILE

Se describen antecedentes de la biologia reproductiva de Dromiciops gliroides provenientes del analisis de cinco hembras colectadas durante la primavera (octubre - diciembre) de 1984 en el sur de Chile. Se examino el desarrollo morfologico de embriones intrauterinos con analisis microscopico y comparandolos con los atributos morfologicos de ocho juveniles en el marsupio (camadas de diciembre). Los embriones intrauterinos mostraron caracteristicas embrionarias tipicas de neonatos altriciales, quienes migran desde la apertura urogenital hasta el marsupio para completar los ultimos estados del desarrollo. D. gliroides es, aparentemente, una especie monoestrica, estacional, produciendo una camada por ano. Se ha registrado un maximo de cuatro crias, con nacimientos que ocurren en la primavera temprana (octubre). El ciclo de vida de D. gliroides se divide en seis distintos periodos: (a) formacion de pareja, (b) desarrollo intrauterino, (c) paricion, (d) desarrollo intramarsupial, (e) excursiones familiares nocturnas, y (f) independencia juvenil. Las relaciones filogeneticas de D. gliroides con marsupiales del neotropico y Australia son consideradas comparando aspectos de su biologia reproductiva y caracteristicas de su historia de vida temprana

Raptor habitat management and its implication on the biological control of the Hantavirus

Rodents have a high impact on human activities, producing economical losses and diseases. One of these diseases is Hantavirus syndrome, whose reservoir is Oligoryzomys longicaudatus. Raptors are the natural biological controllers of rodents, being, therefore, our efficient and effective allies. Despite the existing legal dispositions for protection, 11 of the 33 species of raptors in Chile have conservation problems. We evaluated the effectiveness of nest boxes for Tyto alba, as a way to increase its population and propose a procedure for the biological control of O. longicaudatus. The study area was the National Reserve Lago Peñuelas, Valparaíso, Chile. The variation of population density before and after the installation of the nest boxes was established both for T. alba and rodents. The results show that the nest boxes installed dramatically increased the population and the total density of T. alba, and a significant reduction of the abundance of small mammals was stated. We propose a methodological diagram for the biological control of the reservoir of the Hantavirus, which we have been implementing since 2001.

Estado de arte del conocimiento de las aves rapaces de Chile: Situación actual y proyecciones futuras

El creciente interes a nivel mundial por el estudio de las aves rapaces ha generado la necesidad de identificar las prioridades de investigacion para asi enfocar los esfuerzos de conservacion sobre ellas. En Chile, las primeras investigaciones se inician en 1891, y el numero de publicaciones se ha incrementado considerablemente durante las ultimas decadas. Basados en la informacion publicada entre los anos 1970 y 2011 evaluamos el estado de conocimiento de las aves rapaces de Chile con el proposito de identificar aquellos topicos donde todavia la informacion es deficiente o insuficiente para determinar que tipo de informacion debe priorizarse. Analizamos la informacion de acuerdo a la especie, especies agrupadas (rapaces diurnas y nocturnas), temas de investigacion y area geografica donde se realizaron los estudios. Encontramos que el numero de publicaciones aumento linealmente con el tiempo, pero esta tendencia ha sido fuertemente sesgada hacia solo dos especies (Tyto alba y Geranoaetus polyosoma). La mayor cantidad de estudios realizados en Chile se centraron en el conocimiento de la dieta, con un interes mas acentuado en las rapaces nocturnas que en las diurnas. Los temas de investigacion restantes solo fueron mediana o escasamente considerados. Las aves rapaces menos estudiadas fueron las migratorias (Buteo swainsoni, Pandion haliaetus, Circus buffoni), las especialistas del bosque templado de Sudamerica austral (Strix rufipes, Accipiter bicolor, Buteo ventralis y B. albigula) y aquellas pertenecientes al genero Phalcoboenus, la mayoria de las cuales se encuentran con problemas de conservacion. Los estudios por areas geograficas fueron similares entre rapaces diurnas y nocturnas. Cabe destacar que se observo una alta concentracion de los estudios en las cercanias de Santiago, capital administrativa de Chile. Concluimos que las prioridades de investigacion deben focalizarse sobre: (a) las especies escasamente estudiadas y con problemas de conservacion, (b) temas de investigacion tales como migracion, densidad poblacional, taxonomia, manejo, parasitos y uso y seleccion de habitat, y (c) las especies que habitan ambientes remotos, paisajes fragmentados y/o modificados por el hombre y areas altamente pobladas.

DIETA DE LYCALOPEX GRISEUS (GRAY, 1837) (MAMMALIA: CANIDAE) EN LA DEPRESION INTERMEDIA DEL SUR DE CHILE

A study about food habits of chilla (Lycalopex griseus) was done in a sector of the intermediate depression of southern Chile, called Predio Rucamanque, Region de la Araucania. Faeces were collected through three seasons of the year, identifying their diet composition. Results show a trend towards small mammals followed by birds, and in a lesser ratio, insects.

Trophic ecology of two raptors, Barn Owl (Tyto alba) and White-tailed Kite (Elanus leucurus), and possible implications for biological control of Hantavirus reservoir in Chile

ABSTRACT Raptors are important predators of various species of small mammals, which renders them of economic importance since their prey may be either disease vectors or reservoirs which represent health problems, or economically important through the damage they cause to crops and stocks. The long-tailed rice rat Oligoryzomys longicaudatus is a reservoir and vector of Hantavirus, a disease of increasing importance in various Latin American countries. The nocturnal Barn Owl (Tyto alba) and the diurnal White-tailed Kite (Elanus leucurus) appear to be the most significant predators of this species. Here, we characterize the diet of these two raptors and analyze their trophic specialization and dietary selectivity using published information, pellet analysis, and field abundances of small mammals. Both raptor species positively selected O. longicaudatus in their diets to suggest that they could be potential controllers of the Hantavirus reservoir in Chile, both in natural and agricultural ecosystems. Predation on O. longicaudatus by these two raptors is interesting because they have complementary activity periods, a condition which enables them to share the same prey without having strong interference.

Legal protection assessment of different inland wetlands in Chile

BackgroundInland wetlands are well represented ecosystems in Chile that are subjected to various pressures affecting conservation. Protection means legal and administrative initiatives which promote the protection and/or preservation of a wetland, either in its entirety, considering their areas of influence or its components.ResultsThe aim of this work is to develop a methodology for estimating the value of protection of different types of inland wetlands in Chile. For this purpose: a) the Chilean regulations in relation to the issues of biodiversity, wetlands and water resources were compiled; (b) such legislation and its application were analyzed, (c) protection and restriction values of each legal standard was estimated, and then total protection value of standards applied to six types of wetlands in study. 47 legal rules related to protection of inland wetlands and eight directly or indirectly affecting conservation and wise use of wetlands were identified.ConclusionsIn Chile there is no specific statutory rules or regulations on wetlands. Current legal standards do not protect equally the different types of inland wetlands, being swamp forests, peatlands and brackish Andean lakes less protected. To improve wetlands conservation, incentives promoting wetlands destruction must be eliminated and promulgate specific regulations for proper management and conservation.

Diversidad de micromamíferos en tres ambientes de la Reserva Nacional Lago Peñuelas, Región de Valparaíso, Chile

Los ecosistemas mediterraneos de Chile, los unicos en Sudamerica de los cuatro presentes en el mundo, son considerados areas prioritarias para la conservacion, por su alta concentracion de especies endemicas y las aceleradas tasas de destruccion del habitat. Estos contienen mas del 39% de las especies de mamiferos, 47% de las especies endemicas y el 65% de las especies amenazadas del pais. Aun asi, estos ecosistemas estan inadecuadamente representados en el sistema de areas silvestres protegidas, siendo una de ellas la Reserva Nacional Lago Penuelas (RNLP) parte de la Reserva de Biosfera La Campana-Penuelas. La mastofauna de la RNLP esta pobremente documentada. Estudiamos la diversidad α y β en el ensamble de micromamiferos presentes en los tres ambientes de la RNLP (bosque esclerofilo, matorral mixto y sabana de Acacia caven). Instalamos grillas de trampas Sherman, recolectamos y analizamos egagropilas de dos especies de aves rapaces (Tyto alba y Bubo magellanicus) y registramos huellas, signos y observacion directa en las cuatro estaciones del ano 2001. Determinamos la riqueza de especies (S), abundancia relativa, diversidad a considerando su riqueza y estructura (indices de Shannon y Wiener y de Pielou), diversidad β (indice de Bray-Curtis) y comparamos la diversidad encontrada con lo documentado en la misma latitud de este a oeste. Registramos un total de 16 especies: Thylamys elegans, Oligoryzomys longicaudatus, Abrothrix longipilis, A. olivaceus, Chelemys megalonyx, Phyllotis darwini, Myocastor coypus, Octodon degus, O. lunatus, Spalacopus cyanus, Abrocoma bennetti, Rattus norvegicus, R. rattus, Mus musculus, Lepus capensis y Oryctolagus cuniculus. El bosque esclerofilo costero fue el mas diverso con distribucion homogenea de sus especies, seguido del matorral mixto y fnalmente la sabana de A caven. Por otro lado el bosque esclerofilo es similar al matorral mixto y ambos a su vez muy disimiles de la sabana de A caven. La diversidad registrada en el area de estudio es concordante con la correspondiente a otras areas mediterraneas de Chile. Se discute la situacion de estos ecosistemas y se contrasta la diversidad documentada para seis localidades a la misma latitud.

Zooplankton of the highland bogs of Putana, a desert wetland of the high puna, northern Chile

The Atacama “puna” (high-altitude plateau) is situated among the high peaks of the Andes at over 4000 m a.s.l. This ecosystem covers parts of north-eastern Chile, north-western Argentina, south-eastern Peru, and mid-western Bolivia. The puna brings together several types of wetlands, such as salt-flats, lakes, rivers, high marshes, and highland bogs. Highland bogs are peatlands associated with endorheic basins. The object of this study was to analyse the specific composition and structure of the zooplankton of the bogs of the Putana River, on the Altiplano of northern Chile. In 2012, zooplankton samples were taken for qualitative and quantitative analysis at nine stations of the bog. Nine taxa of zooplanktonic crustaceans were recorded. The species richness is higher than records in other high Andean wetland at a similar altitude, although the species found have been reported for other high Andean wetlands and Andean lakes in Chile and from neighbouring countries.