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Wildlife rehabilitation seeks to return healthy animals back to their natural habitat with good survival prospects, and hence contribute to the persistence of their populations. However, the effectiveness of rehabilitation remains largely undocumented, and its utility as a conservation tool is unclear. In this paper, we document the rehabilitation success of a large, herbivorous marsupial, the common wombat (Vombatus ursinus), and use the findings as a case study to evaluate the contribution that rehabilitation can make to wildlife conservation. Using a database of 54 orphaned wombats monitored for up to eight years, we found that 81.5% of young survived to release and, of those, 77.3% were alive in the wild by the end of the study. Survival during rehabilitation was greater for larger, older animals, but influenced also by problems during care, reaction to human contact following weaning and, in particular, the responses of individuals to treatment. No factors associated with rescue condition, rehabilitation or release affected survival of animals once returned to the wild, suggesting that wombats were not disadvantaged by their progression through rehabilitation. We provide brief recommendations to improve rehabilitation success for wombats. We conclude that rehabilitation is an under-recognized but potentially valuable conservation tool, and suggest that it is timely to consider its contribution to wildlife management more generally. [ABSTRACT FROM AUTHOR]

To determine whether latitudinal and longitudinal gradients in seed mass are related to variation in climatic features including temperature, solar radiation and rainfall. Australia. Seed mass was estimated from over 1600 provenances covering the latitudinal and longitudinal extents of 34 perennial Glycine taxa in Australia. Climatic data were obtained from ANUCLIM 5.1 for collection locations based on long-term meteorological records across Australia. These climatic data were subject to principal components analysis to extract three components as climatic indices. Generalized linear models were used in three separate sets of analyses to evaluate whether seed mass–latitude and seed mass–longitude relationships persisted after taking climatic variation into account. First, relationships were examined across species in analyses that did not explicitly consider phylogenetic relationships. Secondly, phylogenetic regressions were performed to examine patterns of correlated evolutionary change throughout the Glycine phylogeny. Within-species analysis was also performed to examine consistency across different taxonomic levels. Geographical variation in seed mass among species was related primarily to temperature and solar radiation, while rainfall was much less influential upon seed mass. Partialing out the influence of temperature and solar radiation in models resulted in the disappearance of significant seed mass–latitude and seed mass–longitude relationships. Patterns within species were generally consistent with patterns among species. However, in several species, factors additional to these climatic variables may contribute to the origin and maintenance of geographical gradients in seed mass, as significant seed mass–latitude and seed mass–longitude relationships remained after controlling for the influence of climatic variables. Our empirical results support the hypotheses that (1) seed mass is larger at low latitudes and in the interior of the Australian continent due to increased metabolic costs at high temperatures, and that (2) higher levels of solar radiation result in an increase in the availability of photosynthate, which in turn leads to an increase in biomass for the production of large seeds. In effect, our findings show that greater energy is available precisely where needed, that is, where high temperatures require large seed mass on the basis of metabolic requirements. [ABSTRACT FROM AUTHOR]

To test the effects of habitat fragmentation and edge on the rate ofnest predation in an urban ecosystem, 20 artificial nests each containing 2 plasticine eggs were distributed in each of 24 bushland sitesin Sydney, Australia. The eastern yellow robin Eopsaltria australis was adopted as a target species, and variables of nests, eggs and nesting behaviour were manipulated in experiments. Sites ranged in size from 3.8 ha to 14 717 ha and were divided into three size classes: 1)0-10 ha, 2) 11-100 ha and 3) > 101 ha. Nests were positioned either around the edge of the fragment (within 50 m from the fragment boundary) or within the center of the fragment (> 50 m from the fragment boundary). The predation rate was calculated as the percentage of neststhat had one or both eggs damaged or removed after 15 d of exposure.Nest predation rates were high (average 70.6%) but were not affectedby patch size or distance from fragment edges. Predators were identified by marks of the beak or teeth left in the plasticine eggs. Nest predators identified were birds, black rats, brown antechinus and ringtail possum with the majority of predation being by birds (61.7%). Our findings differ from those of most previous studies of nest predation, and perhaps reflect the ubiquity of generalist predators and thedegree of habitat modification throughout remnants of bushland in the urban environment. [ABSTRACT FROM AUTHOR]

Species of terrestrial mammals, reptiles and amphibians were surveyed in patches of semi-natural and disturbed vegetation within the City of Oxford. The patches were delimited by roads, walls or other artificial barriers, and ranged from 0.16 ha to 20 ha. A total of twenty species of mammals was recorded, two to seventeen species occurring per patch. Mammalian species richness (the number of species) within patches decreased with increasing percentage of barren ground per patch, with proximity to buildings, and with patchiness in the total vegetation cover, but increased with increasing density of vegetation in the layer 21–50 cm above ground. Five species of amphibians and four species of reptiles were recorded, zero to seven species occurring per patch. The richness of these taxa within patches increased with patch area, but declined away from sources of permanent water. More species of mammals, amphibians and reptiles were retained in two small habitat patches than in one large patch equal to their combined area. For mammals, excluding large species such as deer, species richness in the urban environment can be preserved by maintaining a system of small (≥0.65 ha) patches of undisturbed woodland throughout the city area. The richness of reptiles and amphibians can probably be preserved by maintaining patches of ≥0.55 ha that provide permanent water. [ABSTRACT FROM AUTHOR]

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