Monday, May 19, 2008

New Red List Released

The 2008 IUCN Red List of Threatened Species has been released. BirdLife reports on the new results for bird species.

The 2008 Red List makes grim reading with 1,226 species of bird now threatened, and eight species newly uplisted to Critically Endangered, the highest threat category. Of the 26 species that changed category owing to changes in their population size, rate of decline or range size, 24 were uplisted to a higher level of threat. These include widespread continental species like Eurasian Curlew Numenius arquata and Dartford Warbler Sylvia undata, both previously of Least Concern, and now regarded as Near Threatened in a global context.

In Australia, Mallee Emuwren Stipiturus mallee is undergoing a very rapid population decline, and its habitat is now so fragmented that a single bushfire could be catastrophic. Years of drought, particularly in the southern and western parts of the species’s range, have affected the health of the vegetation on which it relies and has almost led to the emuwren’s extinction in South Australia where the last significant population comprises 100 birds confined to 100 km².

In the Galápagos Islands, Floreana Mockingbird Nesomimus trifasciatus is confined to two islets off Floreana. Its population has declined from an estimated maximum of 150 individuals in 1966 to fewer than 60, and is now at risk from extreme weather events. As a result it has been uplisted to Critically Endangered.

In Papua New Guinea, deforestation caused by a rising demand for the cultivation of palm oil has led to species such as New Britain Goshawk Accipiter princeps being uplisted to a higher threat category.
A common theme among the species whose status worsened is the impact of climate change. Warmer average temperatures directly affect birds in many ways, such as longer and harsher droughts and stronger storms, both of which degrade critical habitat. Climate change also affects birds by changing the ranges or breeding times for many of the plants or prey species that birds require for food or shelter. These factors have varying effects on common species, but with rare or threatened species, they can push birds closer to the edge.

Here is the list of status changes for bird species. Here is a list of the birds in the U.S. and Canada that are listed as Endangered, Critically Endangered, or Extinct in the Wild. (Many birds on the U.S. list are from Hawaii.) If you want more detail on a particular species or group of species, you can find it through BirdLife's Datazone, which includes factsheets for all of the species in the database.

Information about other taxa on the Red List are available at the IUCN Red List website.