High proportion of cactus species threatened with extinction

A high proportion of plant species is predicted to be threatened with extinction in the near future. However, the threat status of only a small number has been evaluated compared with key animal groups, rendering the magnitude and nature of the risks plants face unclear. Here we report the results of a global species assessment for the largest plant taxon evaluated to date under the International Union for Conservation of Nature (IUCN) Red List Categories and Criteria, the iconic Cactaceae (cacti). We show that cacti are among the most threatened taxonomic groups assessed to date, with 31% of the 1,478 evaluated species threatened, demonstrating the high anthropogenic pressures on biodiversity in arid lands. The distribution of threatened species and the predominant threatening processes and drivers are different to those described for other taxa. The most significant threat processes comprise land conversion to agriculture and aquaculture, collection as biological resources, and residential and commercial development. The dominant drivers of extinction risk are the unscrupulous collection of live plants and seeds for horticultural trade and private ornamental collections, smallholder livestock ranching and smallholder annual agriculture. Our findings demonstrate that global species assessments are readily achievable for major groups of plants with relatively moderate resources, and highlight different conservation priorities and actions to those derived from species assessments of key animal groups.

The conservation dilemma

Aunque el Estado de Florida (Estados Unidos) ha adoptado las directrices de la UICN en cuanto a la aplicación de los criterios de conservación relacionados a su fauna, existe un vacío en términos de que ciertas especies pueden ser protegidas a pesar de no encontrarse en la lista de especies amenazadas y recibir algún nivel de protección. El Parque Nacional Everglades (Florida) es un hábitat crítico para un número de especies raras y otras varias docenas enlistadas como En Peligro o Amenazadas. Sin embargo, un dilema es la interacción entre especies. En este caso, la mosca endémica Melanagromyza miamensis oviposita sus huevos en la inflorescencia de la orquídea Trichocentrum undulatum. En ella, las larvas se desarrollan gen- eralmente matando al tallo. Este es un ejemplo de la interacción entre dos especies, una ampliamente dis- tribuida pero localmente incluida bajo la categoría de Críticamente Amenazada (CR) (T. undulatum) y la especie endémica (M. miamensis). De esta manera, se utiliza este ejemplo para demostrar la complejidad en el desarrollo de un plan de manejo. 

The role of botanic gardens in the science and practice of ecological restoration

Many of the skills and resources associated with botanic gardens and arboreta, including plant taxonomy, horticulture, and seed bank management, are fundamental to ecological restoration efforts, yet few of the world's botanic gardens are involved in the science or practice of restoration. Thus, we examined the potential role of botanic gardens in these emerging fields. We believe a reorientation of certain existing institutional strengths, such as plant-based research and knowledge transfer, would enable many more botanic gardens worldwide to provide effective science-based support to restoration efforts. We recommend botanic gardens widen research to include ecosystems as well as species, increase involvement in practical restoration projects and training practitioners, and serve as information hubs for data archiving and exchange.