Colossal study shows amphibian woes.For anyone who still doubts that amphibian amphibian, in zoology amphibian, in zoology, cold-blooded vertebrate animal of the class Amphibia. There are three living orders of amphibians: the frogs and toads (order Anura, or Salientia), the salamanders and newts (order Urodela, or Caudata), and the populations are declining worldwide, Jeff E. Houlahan has a message: Give up. The ecologist at the University of Ottawa Individual species and places vary, but "at a global scale, amphibians amphibians members of the animal class Amphibia. Includes frogs, toads, newts, salamanders and cecilians all capable of living on land or in water. have declined over the past several decades," Houlahan and four coauthors announce in the April 13 NATURE. "We wanted to just pile the data as high as we could and see if we have declines," Houlahan says. Although he cautions that records before the 1980s are scarce, Houlahan notes that 1960 to 1966 saw the sharpest plunge, perhaps 15 percent overall. Since then, declines have stayed around 2 percent per year. Scientists, however, didn't raise the alarm until the late 1980s. "We were catching on decades late," he laments. Previous evidence came mostly from anecdotes or short-term studies, the team contends. Houlahan started a grander project while a stay-at-home dad caring for toddling twins. In free moments, he sent E-mail asking for data from every amphibian researcher he could find. His team calculated yearly population changes for all the studies. In an approach that's stirring debate, the researchers also tracked ratios of the numbers of declining populations and rising ones. "Many frog populations should decrease more often than they increase," argues Ross A. Alford of James Cook University Situated in the tropical gardens of the campus, the halls of residence provide students with modern social and sporting facilities as well as the opportunity to choose between catered or self-catered accommodation. in Townsville, Australia. One population boom gets whittled away by several seasons of dwindling dwin·dle v. dwin·dled, dwin·dling, dwin·dles v.intr. To become gradually less until little remains. v.tr. To cause to dwindle. See Synonyms at decrease. . Houlahan's second analysis therefore "could be misleading," Alford says. Despite his questions, Alford agrees with the study's conclusion. So does Joe Pechmann of the University of New Orleans History UNO was founded in 1958 as the New Orleans branch of Louisiana State University, originally as "Louisiana State University in New Orleans" or "LSUNO", but became more independent and changed the name to "University of New Orleans" in 1974. , who in a 1991 article cautioned against labeling every population dip a decline. Few if any herpetologists This is a list of herpetologists who have articles, in alphabetical order by surname. A-D
The international director for the task force, Tim Halliday of the Open University in Milton Keynes, England, comments that Houlahan's results could come "largely from the impact of habitat destruction alone." Against that backdrop, he sees local assaults from climate change, disease, pollution, and ultraviolet radiation. The director of the longest-running daily frog census, according to the Guinness Book of World Records, makes no special claims about amphibian declines. Whit Gibbons Famous people named Gibbons include:
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