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Growing light pollution is increasingly studied in terrestrial environments. However, research on night lights in coastal ecosystems is limited. We aimed to complement spaceborne remote sensing with ground-based hemispheric photos to quantify the exposure of coastal habitats to light pollution. We used a calibrated DSLR Canon camera with a fisheye lens to photograph the night sky in 24 sites in the rapidly developing area of Moreton Bay, Queensland, Australia, extracting multiple brightness metrics. We then examined the use of the LANcubeV2 photometer and night-time satellite data from SDGSAT-1 for coastal areas. We found that the skies were darker in less urbanized areas and on islands compared with the mainland. Sky brightness near the zenith was correlated with satellite observations only at a coarse spatial scale. When examining light pollution horizontally above the horizon (60–80° degrees below the zenith), we found that the seaward direction was brighter than the landward direction in most sites due to urban glow on the seaward side. These findings emphasize the importance of ground measurements of light pollution alongside satellite imagery. In order to reduce the exposure of coastal ecosystems to light pollution, actions need to go beyond sites with conservation importance and extend to adjacent urban areas. [ABSTRACT FROM AUTHOR]

Predator exclosure reserves have become pivotal to conserving some threatened Australian mammalian fauna. However, the impact of predator exclosure reserves on resident (non‐target) small vertebrates is less understood. Given the potential ecological consequences of fencing, and the contribution of small vertebrates to ecosystem processes, we investigated species' occupancy, and site colonization and extinction dynamics, inside and outside of a predator exclosure fenced area for nine small vertebrates (six reptile, three mammal). We conducted vertebrate surveying 4 years (2011–2014) pre‐ and 2 years (2015–2016) post‐fence construction at the Australian Wildlife Conservancy Mt Gibson Sanctuary, in the semi‐arid, critically endangered Wheatbelt Eucalypt Woodlands of Western Australia, to assess spatial and temporal trends in small mammal and reptile populations. Of nine species modelled, one reptile (Diplodactylus pulcher) decreased in occupancy inside of the fence following construction. We detected no negative impact of the predator exclosure fence on the remaining eight species. One native reptile species (Lerista kingi) and an introduced rodent (Mus musculus) increased occupancy inside (but not outside) the fenced area. Spatial and temporal occupancy inside and outside of the fenced area for all other modelled species was stable. Biotic (habitat) factors and stochastic interannual detectability were the most significant drivers of species' occupancy. Species‐specific habitat associations were partially determined by site‐based presence and absence probabilities. This suggests that the predator exclosure sanctuary either benefitted or had minimal impact on all but one modelled species. These results may be a useful reference for future fencing projects aimed at both conservation and land management. [ABSTRACT FROM AUTHOR]

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] [...]

This paper aims to quantify land cover and vegetation changes over the past 250 years on Norfolk Island, Australia, a remote island important for its cultural heritage and biodiversity. We collated over 130 historical maps and aerial photos from various archives, of which we georeferenced 80. Supervised classification and manual digitization were used to extract detailed land cover information on vegetation cover from 10 historical maps and datasets. While the classification and symbology used to represent vegetation on the different maps varied over time, we were able to track changes in vegetation cover on the island. We found that after the first (colonial) settlement, non-agricultural vegetation cover was at its lowest during the 1940s, and has since then expanded. We found high constancy of land cover patterns on the island since 1840 onwards. Historical maps thus provide an understanding of the dynamics that shape the present landscape. [ABSTRACT FROM AUTHOR]

Simple Summary: We aimed to investigate how an invasive cavity-breeding bird, the common (Indian) myna, and a native nest predator, the common brushtail possum, influence urban nest box use by native birds in Queensland and New South Wales, Australia. We quantified nest box use by invasive and native species, assessed nesting success and failure rates, and explored what environmental factors might influence nest box occupancy and nesting success. We found that the native possums were the most common nest box users and that possum occupancy of boxes was associated with higher rates of nesting failures by all bird species. More common myna nesting attempts were observed in areas where mynas have been established longer. We found no evidence of a significant negative impact by the common myna on other birds in our study locations, which may be partly due to the low rates of use of our nest boxes by native birds. Nevertheless, better nest box design and guidelines for setting them up are needed if we aim to provide more nesting opportunities for native birds to replace the decline in big old cavity trees. Many bird species in Australia require tree hollows for breeding. However, assessing the benefits of urban nest boxes to native birds requires frequent monitoring that allows to assess nesting success. To better understand the benefits of nest boxes for native birds, we examined the impact of local habitat characteristics, invasive species (common myna, Acridotheres tristis), and native mammalian predators on urban nest box use and nesting success of native birds. We installed 216 nest boxes across nine locations in southeastern Australia (S.E. Queensland and northern New South Wales) in both long-invaded sites (invaded before 1970) and more recently invaded sites (after 1990). We monitored all boxes weekly over two breeding seasons. We recorded seven bird species and three mammal species using the nest boxes. Weekly box occupancy by all species averaged 8% of all boxes, with the species most frequently recorded in the nest boxes being the common brushtail possum (Trichosurus vulpecula), a native cavity user and nest predator. We recorded 137 nesting attempts in the boxes across all bird species. The most frequent nesting species were the invasive alien common mynas (72 nesting attempts). We recorded an average nesting failure rate of 53.3% for all bird species. We did not record any common mynas evicting other nesting birds, and found that several native species used the same box after the common myna completed its nesting. We recorded native possums in 92% of the boxes, and possum occupancy of boxes per site was negatively correlated with bird nesting success (p = 0.021). These results suggest that when boxes are accessible to invasive species and native predators, they are unlikely to significantly improve nesting opportunities for native birds. To ensure efficient use of limited conservation resources, nest boxes should be designed to target species of high conservation importance and limit other species of both predators and competitors. [ABSTRACT FROM AUTHOR]

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.)