No abstract

No abstract

RESUMENLa Estación Biológica Senda Darwin (EBSD) constituye un centro de investigación inmerso en el paisaje rural del norte de la Isla de Chiloé (42º S), donde fragmentos del bosque siempreverde original coexisten con praderas de uso ganadero, turberas de Sphagnum, matorrales sucesionales, plantaciones de Eucalyptus y otras formaciones de origen antropogénico. Desde 1994 hemos realizado estudios de largo plazo centrados en algunas especies de plantas (e.g., Pilgerodendron uviferum D. Don) y animales (e.g., Aphrastura spinicauda Gmelin, Dromiciops gliroides [Thomas]) catalogados como amenazados o escasamente conocidos y en ecosistemas nativos de importancia regional y global (e.g., turberas de Sphagnum, bosque Valdiviano y Nordpatagónico). Las investigaciones han considerado las respuestas de las especies y de los ecosistemas frente al cambio antropogénico del paisaje y cambio climático, así como los efectos de diferentes formas de manejo. Este escenario es semejante al de otras regiones de Chile y Latinoamérica lo que da generalidad a nuestros resultados y modelos. En este período, investigadores asociados a la EBSD han producido más de un centenar de publicaciones en revistas nacionales e internacionales y 30 tesis de pre y postgrado. Entendiendo el papel clave de los seres humanos en los procesos ecológicos de la zona rural, la EBSD ha desarrollado un programa de educación ecológica y vinculación del avance científico con la sociedad local y nacional. La integración de la EBSD a la naciente red de Sitios de Estudios Socio-Ecológicos de Largo Plazo en Chile consolidará y fortalecerá la investigación básica y aplicada que realizamos para proyectarla hacia la siguiente década. and animals (e.g., Aphrastura spinicauda, Dromiciops glirioides) that are considered threatened, poorly known or important for their ecological functions in local ecosystems, and on ecosystems of regional and global relevance (e.g., Sphagnum bogs, North Patagonian and Valdivian rain forests). Research has assessed the responses of species and ecosystems to anthropogenic land-use change, climate change, and the impact of management. During this period, more than 100 scientific publications in national and international journals, and 30 theses (graduate and undergraduate) have been produced by scientists and students associated with SDBS. Because of our understanding of the key role that humans play in ecological processes at this agricultural frontier, since the establishment of SDBS we have been committed to creative research on the communication of science to society and ecological education. The integration of SDBS to the nascent Chilean network of long-term socio-ecological research will consolidate and strengthen basic and applied research to project our work into the next decade.Key words: biodiversity, education, long-term socio-ecological research, private protected area, temperate rainforests. INTRODUCCIÓNLos bosques templados del sur de Sudamérica, distribuidos entre los 35° y 55º S en el margen occidental del continente, se carac...

In South American temperate rainforests, five endemic understory birds (four Rhinocryptidae and one Furnariidae) are often associated with the main understory plant, the native bamboo Chusquea valdiviensis (Poaceae: Bambusoideae). We studied the effects of bamboo cover on species abundance and richness of those understory birds and explored the functions of bamboo as food resource and escape cover. In Chiloé Island (42°S), southern Chile, we selected four old-growth forest patches >100 ha and in each patch conducted bird surveys in six plots with >70% understory cover. Three plots were dominated by native bamboo and three plots had a sparse bamboo cover. Bird abundance (point counts) was significantly correlated with both total understory cover and percentage of bamboo cover but was not correlated with other kinds of understory plant cover. Bird species richness was positively correlated with bamboo cover and negatively correlated with other kinds of understory cover but unrelated to total understory cover. Leaf-gleaners Magellanic Tapaculos (Scytalopus magellanicus), Ochre-flanked Tapaculos (Eugralla paradoxa), and Des Murs's Wiretails (Sylviorthorhynchus desmursii), and the ground-gleaner Chucao Tapaculos (Scelorchilus rubecula) were more abundant in high-bamboo plots; but the ground-gleaner Black-throated Huet-huet (Pteroptochos tarnii) was recorded more times in plots with low-bamboo cover.Availability of invertebrates per unit of understory dry mass did not differ between high- and low-bamboo plots; but plant biomass was greater in high-bamboo plots, so total invertebrate abundance per plot was higher there. Ground-litter invertebrate abundance was similar in all plots. To examine escape-cover preferences, nine captured Chucao Tapaculos were released in front of two different understory scenarios (high-bamboo cover or bamboo-free understory); 88% of released birds moved into bamboo cover. We suggest that the structure of native bamboo understory is critical for the maintenance of four of those species, and retaining bamboo cover in managed stands may help minimize the effect of logging on understory birds.

Effects of avian gut-passage on seed germination are important to assess the effectiveness of frugivores in woodland regeneration, particularly in biodiversity hotspots that have a high incidence of avian frugivory. We examined the effect of avian gut-passage on seed germination in contrast to seeds that remain uneaten in five shrub species in Mediterranean central Chile and sought to determine the physiological mechanism(s) by which seed germinability is modified. Germination assays were conducted in a glasshouse for five common shrub species of the sub-Andean matorral: Azara dentata (Flacourtiaceae), Schinus polygamus and Schinus molle (Anacardiaceae), Cestrum parqui (Solanaceae), and Maytenus boaria (Celastraceae). We estimated germinability (final percent germination), dormancy length (time from sowing to first germination), mean length of dormancy of all germinated seeds, and contrasted germination rates of defecated versus manually extracted and pulp-enclosed seeds. Avian gutpassage increased seed germinability in four of the five shrub species studied-primarily through deinhibition via pulp removal. Minimum dormancy length was not modified by avian gut-passage for A. dentata, but was significantly shorter for S. molle and C. parqui. Mean dormancy length was significantly shorter in gut-passed seeds of A. dentata, S. molle and M. boaria. Avian gutpassage greatly enhanced the seed germination rates of three species, A. dentata, S. molle and C. parqui. We conclude that the positive effects of birds on seed germination facilitate the regeneration of sub-Andean shrublands, and that bird declines due to landscape change may impair recovery rates of successional or restored areas due to dispersal limitation.

Monitoring the establishment of plant pests enables national plant protection organizations to understand trends in biosecurity threats and thus modify their regulatory and management responses. A dataset of the 267 invertebrate pests establishing in Great Britain was compiled for the period 1970–2013. The number of establishments observed ranged between 1 and 13 per year. A study of time lags between the detection and reporting of new establishments showed that approximately 50% of new plant pests were reported after 2 years and 95% after 10 years. Therefore, the number of very recent establishments (and hence establishment rates) is underestimated. Correcting for the reporting lag, the annual rate of establishment was stable until the late 1980s, at approximately four species per year. Afterwards, the mean annual rate approached nine species per year. Approximately 50% of established species occurred only on hosts in the ornamental sector, approximately 25% in both wild and ornamental situations, and 25% only in the wild. Less than 5% of species pose a threat to economic sectors.

No abstract

RESUMENSe realizó un catastro de los mamíferos, aves, reptiles y anfibios presentes en seis hábitats de la Reserva Nacional Futaleufú, provincia de Palena, Chile. Estos hábitats se encuentran desde la cota 700 hasta los 2000 msnm, ellos son: cipresal, matorral mixto, bosque de lenga y coigüe, renoval de Nothofagus, mallín y bosque achaparrado de ñirres en sectores altos de roqueríos con nieves estacionales. Se registraron un total de 60 especies de vertebrados en la Reserva: 17 especies de mamíferos, 38 especies de aves, cuatro especies de anfibios y una especie de reptil. Se destaca la presencia de huemules en casi todos los hábitats. El análisis por hábitat muestra una mayor riqueza de especies en los bosques de lenga-coigüe, los cuales presentan además una mayor heterogeneidad estructural. El matorral mixto, que limita con praderas y campos agrícolas, y los renovales de Nothofagus representan el segundo y tercer hábitat con mayor riqueza. Se advierte la fragilidad del sistema para mantener poblaciones de vertebrados, pues hacia el borde de la Reserva se produce una interfase entre el uso por animales domésticos (perros, ganado y caballos) y la fauna silvestre endémica o con problemas de conservación.PALABRAS CLAVES: Biodiversidad, áreas silvestres protegidas, fauna patagónica. ABSTRACTWe surveyed the mammals, birds, reptiles and amphibians in six distinct habitat types in the Futaleufú National Reserve, in the province of Palena, Chile. These habitats occur from 700 masl up to 2.000 masl: cypress forest, mixed shrubland, lenga and coigüe forest, early successional Nothofagus tree areas, scrubland and ñirre trees in rocky areas with seasonal snow. A total of 60 species were recorded in the Reserve: 17 terrestrial mammals, 38 bird species, four amphibians and one reptile species. We highlight the presence of huemules in almost all the habitats. Habitat type analysis showed that lenga-coigüe forests have the highest species richness for all taxa, besides having also a higher structural heterogeneity. The mixed shrubland, which limits with pastures and agriculture fields, together with the early successional Nothofagus tree areas represent the second and third habitats with highest species richness. We warn of the fragility of the system for the maintenance of vertebrate populations, because towards the edge of the Reserve, an interface results between the use by domestic animals (dogs, livestock and horses) and the wild endemic fauna or with conservation problems.