Guidelines for selecting an appropriate currency in biodiversity offset transactions

When designing biodiversity offset transactions, selecting the appropriate currency for measuring losses and gains to biodiversity is crucial. Poorly designed currencies reduce the likelihood that the proposed offset will sufficiently compensate for the development impact on the affected biota. We present a framework for identifying appropriate offset currencies for terrestrial biodiversity features, either vegetation communities or particular species. The guidelines were developed based on a review of issues and solutions presented in the existing literature, including government policies and guidance. We assert that while benchmark-based condition scores provide a suitable offset transaction currency for vegetation communities, this approach is also commonly applied to individual species based on the often-unproven assumption that vegetation quality is a proxy for the value of a site to that species. We argue that species are better served by species-specific currencies based on either species abundance, or the suitability and amount of the habitat available. For species where it is practical and meaningful to measure the abundance on site, an abundance-based currency using either directly observable or proxy indicators is the most representative measure of the net impact on the species. In other instances, such as when species are difficult to locate, or not reliably present on site, a currency based on the quality and amount of habitat is preferable. The habitat-quality component should be measured relative to its value for the species, with the most important attributes weighted accordingly. Ensuring the currency used in biodiversity offset transactions is practical to measure, and relevant to the species or vegetation community is an important step in minimising the net biodiversity losses from unavoidable impacts.

Quantifying extinction risk and forecasting the number of impending Australian bird and mammal extinctions

A critical step towards reducing the incidence of extinction is to identify and rank the species at highest risk, while implementing protective measures to reduce the risk of extinction to such species. Existing global processes provide a graded categorisation of extinction risk. Here we seek to extend and complement those processes to focus more narrowly on the likelihood of extinction of the most imperilled Australian birds and mammals. We considered an extension of existing IUCN and NatureServe criteria, and used expert elicitation to rank the extinction risk to the most imperilled species, assuming current management. On the basis of these assessments, and using two additional approaches, we estimated the number of extinctions likely to occur in the next 20 years. The estimates of extinction risk derived from our tighter IUCN categorisations, NatureServe assessments and expert elicitation were poorly correlated, with little agreement among methods for which species were most in danger – highlighting the importance of integrating multiple approaches when considering extinction risk. Mapped distributions of the 20 most imperilled birds reveal that most are endemic to islands or occur in southern Australia. The 20 most imperilled mammals occur mostly in northern and central Australia. While there were some differences in the forecasted number of extinctions in the next 20 years among methods, all three approaches predict further species loss. Overall, we estimate that another seven Australian mammals and 10 Australian birds will be extinct by 2038 unless management improves.

Biological, ecological, conservation and legal information for all species and subspecies of Australian bird

We introduce a dataset of biological, ecological, conservation and legal information for every species and subspecies of Australian bird, 2056 taxa or populations in total. Version 1 contains 230 fields grouped under the following headings: Taxonomy & nomenclature, Phylogeny, Australian population status, Conservation status, Legal status, Distribution, Morphology, Habitat, Food, Behaviour, Breeding, Mobility and Climate metrics. It is envisaged that the dataset will be updated periodically with new data for existing fields and the addition of new fields. The dataset has already had, and will continue to have applications in Australian and international ornithology, especially those that require standard information for a large number of taxa.

The impact of conservation on the status of the world's vertebrates

Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups: agricultural expansion, logging, overexploitation, and invasive alien species.