Preliminary Conservation Assessments Research Articles

Measuring the fate of plant diversity: towards a foundation for future monitoring and opportunities for urgent action

Vascular plants are often considered to be among the better known large groups of organisms, but gaps in the available baseline data are extensive, and recent estimates of total known (described) seed plant species range from 200000 to 422000. Of these, global assessments of conservation status using International Union for the Conservation of Nature (IUCN) categories and criteria are available for only approximately 10000 species. In response to recommendations from the Conference of the Parties to the Convention on Biological Diversity to develop biodiversity indicators based on changes in the status of threatened species, and trends in the abundance and distribution of selected species, we examine how existing data, in combination with limited new data collection, can be used to maximum effect. We argue that future work should produce Red List Indices based on a representative subset of plant species so that the limited resources currently available are directed towards redressing taxonomic and geographical biases apparent in existing datasets. Sampling the data held in the world's major herbaria, in combination with Geographical Information Systems techniques, can produce preliminary conservation assessments and help to direct selective survey work using existing field networks to verify distributions and gather population data. Such data can also be used to backcast threats and potential distributions through time. We outline an approach that could result in: (i) preliminary assessments of the conservation status of tens of thousands of species not previously assessed, (ii) significant enhancements in the coverage and representation of plant species on the IUCN Red List, and (iii) repeat and/or retrospective assessments for a significant proportion of these. This would result in more robust Sampled Red List Indices that can be defended as more representative of plant diversity as a whole; and eventually, comprehensive assessments at species level for one or more major families of angiosperms. The combined results would allow scientifically defensible generalizations about the current status of plant diversity by 2010 as well as tentative comments on trends. Together with other efforts already underway, this approach would establish a firmer basis for ongoing monitoring of the status of plant diversity beyond 2010 and a basis for comparison with the trend data available for vertebrates.

Modeling species’ geographic distributions for preliminary conservation assessments: an implementation with the spiny pocket mice ( Heteromys) of Ecuador

GIS-based modeling of a species’ environmental requirements using known occurrence records can provide estimates of its distribution for conservation assessments when other data are lacking. We used collection records, environmental variables, maps of land cover and protected areas, and the Genetic Algorithm for Rule-Set Prediction (GARP) to estimate the historical, current, and protected ranges of the spiny pocket mice present in Ecuador ( Heteromys australis and H. teleus). The results suggest that ca. 52–63% of the distributional areas of H. australis in the country are intact, but suitable habitat in protected areas represents only approximately 11–13% of the species’ historical range there. The distribution of H. teleus has been much more reduced, with only ca. 13–19% of its historical distribution still forested and an estimated 2–3% intact and falling in protected areas. Our work highlights critical areas for future fieldwork and demonstrates an integrated approach to estimating a species’ current distribution for preliminary conservation assessments.