Diversity, flower visitation frequency and generalism of pollinators in temperate rain forests of Chiloé Island, Chile

Abstract

Species richness and taxonomic composition of pollinator assemblages are documented for 26 plant species from temperate rain forests of northern Chiloé Island, southern Chile (42∞30¢S). We investigated the patterns of generalism and specialization among plants and animal pollinators by comparing the flower visit frequency by different pollen vectors during the spring and summer months of three consecutive years (2000)(2001)(2002). Species studied exhibited a range of floral morphologies (radial vs. zygomorphic, open vs. tubular) and rewards (nectar and/or pollen). Overall, we recorded 172 pollinator species, with an average of 6.6 species of pollen vectors/plant species. Pollinators visited an average of 15.2 plant species/pollen vector. Pollinator assemblages were dominated by Coleoptera (75 species), Diptera (56 species) and Hymenoptera (30 species), but passerine birds and hummingbirds were also important. The most specialized plants were vines, including the bee-pollinated genus Luzuriaga (Philesiaceae) and two endemic species of hummingbird-pollinated Gesneriaceae. Hymenoptera contributed 41.2% of all visits, with the bumblebee Bombus dalhbomii accounting for 22.5% of these. Plants with unspecialized flower morphology supported a higher species richness of pollinators, but visiting rates did not differ from specialized flowers.

Estación Biológica Senda Darwin: Investigación ecológica de largo plazo en la interfase ciencia-sociedad

“…La mayoría de las especies del bosque templado tienen polinizadores bióticos (SmithRamírez & Armesto 1994, Smith-Ramírez 1993, Riveros 1991. La red de interacciones plantapolinizador del bosque del norte de Chiloé incluye 128 especies de polinizadores y 26 especies de plantas, con un total de 316 interacciones mutualistas (Smith-Ramírez et al 2005). Los estudios se han concentrado en 11 especies de arbustos, 9 de árboles y 5 enredaderas.…”

“…var. ovata (Smith-Ramírez et al 2005) y Eucryphia cordifolia (C. Smith, datos no publicados) en fragmentos de bosque y en árboles aislados del paisaje rural, muestran que la riqueza de especies de polinizadores y frecuencia de visitas fue variable entre años (E. cordifolia) y dependiente del tamaño del fragmento (E. coccineum) (Smith-Ramírez et al 2007). En el caso de E. cordifolia y las especies de mirtáceas hemos registrado un patrón inverso de la frecuencia de visitas de abeja europea Apis mellifera Linnaeus y el abejorro nativo B. dalhbomii, en años alternados.…”

An inexpensive portable platform for wildlife observation in the forest canopy

“…When tested, it allowed extremely comfortable fieldwork du ring each four-hour birdwatching session. This swing is perfectly suitable for observing any wildlife in the forest canopy, such as arboreal mammals or flower pollinators (Smith-Ramírez et al 2005), as well as birds in their nests and birds as they move over the canopy from emergent trees (Loiselle 1988, Munn 1991, but its utility is not res tricted to wildlife observations. It offers a suitable stan dpoint for wildlife photography, observation of raptors' nests in cliffs or it can simply be used to rest and contem plate the scenery when climbing a tree just for fun.…”

Árboles monumentales: un patrimonio natural no reconocido en Chile

“…Además, existe una relación positiva entre la riqueza de epifitas y el tamaño de los árboles (Muñoz et al 2003). Asimismo, grandes árboles de ulmo son clave en su interacción con insectos polinizadores (Smith-Ramírez et al 2005) y como hábitat para diversas especies de animales (Díaz et al 2010b). Por lo tanto, los árboles de grandes dimensiones sostienen gran parte de la biodiversidad en los bosques.…”