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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.