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Tree hollows are an important resource for cavity‐nesting birdlife. When large, old trees are removed from a landscape, nest boxes are often installed as part of restoration efforts to replace lost natural cavities. If nest boxes are to be successful conservation tools, non‐target species, particularly competitive and predatory species, need to be prevented from entering nest boxes. Several different modifications to nest boxes aimed at excluding non‐target species have been trialed in previous studies. We tested the effectiveness of reducing the entrance diameter of nest boxes to exclude non‐target species in Southeast Queensland, Australia. We used restrictor plates to reduce the entrance diameter of nest boxes from 90 to 60 and 50 mm and compared the wildlife occupancy of nest boxes with these three entrance diameters. We found that Common brushtail possums, a predator of cavity‐nesting birds and eggs, were significantly less likely to occupy nest boxes with reduced entrance diameters and were excluded from nest boxes with a 50‐mm entrance diameter. Squirrel gliders occupied nest boxes with all three entrance diameters. Introduced species, namely the Common myna and the European honeybee, also occupied nest boxes with restrictor plates. Installation of nest boxes with reduced entrance diameters is a simple and effective strategy to exclude brushtail possums from nest boxes. However, a reduced entrance diameter cannot exclude other non‐target species, and we suggest that other exclusion strategies should be used in conjunction with reduced entrance diameters to increase the occupation of nest boxes by native birds. [ABSTRACT FROM AUTHOR]

Human-mediated translocation of species to areas beyond their natural distribution (which results in 'alien' populations.sup.1) is a key signature of the Anthropocene.sup.2, and is a primary global driver of biodiversity loss and environmental change.sup.3. Stemming the tide of invasions requires understanding why some species fail to establish alien populations, and others succeed. To achieve this, we need to integrate the effects of features of the introduction site, the species introduced and the specific introduction event. Determining which, if any, location-level factors affect the success of establishment has proven difficult, owing to the multiple spatial, temporal and phylogenetic axes along which environmental variation may influence population survival. Here we apply Bayesian hierarchical regression analysis to a global spatially and temporally explicit database of introduction events of alien birds.sup.4 to show that environmental conditions at the introduction location, notably climatic suitability and the presence of other groups of alien species, are the primary determinants of successful establishment. Species-level traits and the size of the founding population (propagule pressure) exert secondary, but important, effects on success. Thus, current trajectories of anthropogenic environmental change will most probably facilitate future incursions by alien species, but predicting future invasions will require the integration of multiple location-, species- and event-level characteristics. Bayesian hierarchical regression analysis of a global database of bird introduction events reveals the environmental, climatic and biotic factors that are the primary determinants of the successful establishment of populations of alien species., Author(s): David W. Redding [sup.1] , Alex L. Pigot [sup.1] , Ellie E. Dyer [sup.1] , Çagan H. Sekercioglu [sup.2] [sup.3] , Salit Kark [sup.4] , Tim M. Blackburn [sup.1] [...]

Among potential topics in the new science of biodiversity, understanding the characteristics and impact of invasive birds is an attractive subject to include as part of junior high school biology studies. Birds are aesthetic and raise curiosity. Curiosity about birds, combined with field observations, can stimulate students to ask authentic questions. As birds are among the few wild vertebrates that one can easily observe, students can easily develop systematic methods to answer their questions and initiate a dynamic open inquiry process. The educational project "Tracking Invasive Birds," presented here as a case study, is the result of a unique collaboration among conservation biologists, science educators and biology teachers. High school students participated in an open inquiry process facilitated by teachers, ecologists, and science educators. At the end of the inquiry process, these high school students conducted a bird watching tour for junior high school students. This paper shows how investigating a conservation environmental issue--invasive birds--contributes to the development of both dynamic open inquiry skills and environmental literacy among 11th- and 12th-grade students. (Contains 2 figures and 1 table.)