Nest boxes in Pinus radiata woodlands in southern Chile: A tool to mitigate negative environmental impacts?
- Biodiversity is affected by forest monoculturing of exotic species, along with wild habitat loss, appear as the principal causes of the conservation problems affecting wild Chilean bird species. Many of these species do not inhabit Pinus radiata due to its homogeneity and the scarcity of habitable havens. To assess the acceptance (habitableness and nesting) of nest boxes in stands of P. radiata in southern Chile, 116 artificial nests, with lures designed to attract insectivores, were installed. Bird houses were highly accepted in the two study areas (98.4% in Temuco and 66.6% in Valdivia). An increase in acceptance was noted, starting in October (1992), reaching practically 100% occupation by February (1993). The percentage of operable houses was maintained high throughout the study. Troglodytes aedon (house wren) occupied almost all of the houses, with only one house occupied by Passer domesticus (house sparrow). T. aedon constructed cup-shaped nests with a base of branches of Ulex europaeus, P. radiata, Rubus ulmifolius, leaves of Eucaliptus, globulus and, in the upper part, animal material such as feathers. The needles of P. radiata were the preferred construction material. The use of bird house to attract birds is successful, and ii we improve the habitat for the bird, it is possible to attract them to the exotic forests of P. radiata. The nests we built are of low cost, and, combined with management techniques such as perches, footpaths and agroforestry, could have benefits on the preservation of biodiversity and the biological control of forest plagues, which in turn could imply a mitigation of negative environmental impacts of the monoculture plantations and similar stands of P. radiata.