The owls of Chile

Abstract

To achieve a better understanding of the life histories of Chilean owls and to generate a useful source of information for future studies, we undertook an exhaustive review of all available information relating to their taxonomy, natural history, ecology, genetic and conservation biology. Studying these topics we gathered information on morphology, morphometrics, distribution, abundance, habitat, reproduction, longevity, behaviour, diet, feeding ecology, population ecology, community ecology, functional ecology, ecophysiology, endemism, conservation status, threats, human perception, legislation, education and outreach, physical rehabilitation, and habitat management. During our review, we rediscovered and retrieved naturalist's observations that had remained totally unknown to contemporary ornithologists. Some of the challenges that must be addressed to achieve a clearer understanding of the biology of Chilean owls and strengthen conservation strategies are (i) to definitively determine the validity of Bubo magellanicus as a separate species and establish the true extent of its distributional hiatus; (ii) to determine the geographic boundaries for Glaucidium nana and G. peruanum; (iii) to detect the ocurrence of population size variations and to identify possible causal factors; (iv) to identify variables that promote the use of, and preference for, habitats; (v) to ascertain, in detail, their reproductive characteristics, home ranges, and dynamic movements; (vi) to assess their diets in poorly studied ecosystems; (vii) to determine their relevance in local food webs and roles in ecosystems; (viii) to evaluate the genetic structure of owls in highly fragmented landscape; and (ix) to promote much more education about their natural history. We think that our review will be useful both in guiding new conservation efforts and opening new research perspectives that will help fill information gaps.