The maps have been produced by nine eminent biologists through the International Union for Conservation of Nature (IUCN). This came about through a review of biodiversity published in the journal
Science.
The new maps reveal trouble spots for the world’s imperiled birds. In South America, for example, there are two areas where unusually high concentrations of birds are at risk of extinction: southeastern Brazil plus a strip along the northwest coast of the continent. One of the birds at risk is the
red-billed curassow (
Crax blumenbachii). The bird ranks as endangered on the IUCN conservation group’s list. Forest loss and hunting have thinned the estimated population, in eastern Brazil, down to around 250 birds.
Another bird at risk is the
giant antpitta (
Grallaria gigantea), which lives in Andean forests in an area of Ecuador and southeastern Colombia that’s smaller than New Jersey. Rated as vulnerable to extinction by conservation monitors, the species’ whole estimated population is less than 2,500 birds.
Some birds in the region are faring better. For instance, the
bay-headed tanager (
Tangara gyrola), lives in a wide sweep from Venezuela south to Bolivia and east into Brazil. Trends in Amazonian forest depletion suggest this habitat will shrink, but at the moment the bird is in the conservation category of least concern.
The authors’ analysis suggests that newly discovered birds are more likely than older, well-known species to be naturally rare and have small ranges. The main risks to bird populations come about through human activity.
The
Science Magazine paper is titled “The biodiversity of species and their rates of extinction, distribution, and protection.”