The world is losing its large carnivores, their ranges are collapsing and many species are at risk of extinction.
“Promoting tolerance and coexistence with large carnivores is a crucial societal challenge that will ultimately determine the fate of Earth’s largest carnivores and all that depends upon them, including humans,” write the co-authors of a review article, in the Jan. 10 issue of Science, about the largest carnivore species on Earth. (more…)
HONOLULU — While the iconic Haleakalā silversword plant made a strong recovery from early 20th-century threats, it has now entered a period of substantial climate-related decline. New research published this week warns that global warming may have severe consequences for the silversword in its native habitat.
Known for its striking rosette, the silversword grows for 20-90 years before the single reproductive event at the end of its life, at which time it produces a large (up to six feet tall) inflorescence with as many as 600 flower heads. The plant was in jeopardy in the early 1900s due to animals eating the plants and visitors gathering them. With successful management, including legal protection and the physical exclusion of hoofed animals, the species made a strong recovery, but since the mid-1990s it has entered a period of substantial decline. A strong association of annual population growth rates with patterns of precipitation suggests the plants are undergoing increasingly frequent and lethal water stress. Local climate data confirm trends towards warmer and drier conditions on the mountain, which the researchers warn will create a bleak outlook for the threatened silverswords if climate trends continue. (more…)
*However, researchers say, global extinction crisis remains very serious*
The most widely used methods for calculating species extinction rates are “fundamentally flawed” and overestimate extinction rates by as much as 160 percent, life scientists report May 19 in the journal Nature.
However, while the problem of species extinction caused by habitat loss is not as dire as many conservationists and scientists had believed, the global extinction crisis is real, says Stephen Hubbell, a distinguished professor of ecology and evolutionary biology at UCLA and co-author of the Nature paper. (more…)
