Mangrove-dependent animals globally threatened
EurekAlert 1 Jul 09;
Extinction looms for amphibians, reptiles, mammals, and birds restricted to declining mangrove forests
More than 40 percent of a sample of amphibians, reptiles, mammals, and birds that are restricted to mangrove ecosystems are globally threatened with extinction, according to an assessment published in the July/August issue of BioScience.
The study, by David A. Luther of the University of Maryland and Russell Greenberg of the Smithsonian Migratory Bird Center, was based on an extensive literature search and expert consultations. The conclusions emphasize the vulnerability of animals that are dependent on a habitat rapidly being lost or degraded through coastal development, overexploitation, pollution, and changes in sea level and salinity.
Mangroves, which are salt-tolerant woody plants concentrated along coastal margins, generally in warm regions, have long been known to support many species of animals. Hundreds of vertebrates are sometimes found in mangroves, but Luther and Greenberg concentrated on the 69 terrestrial vertebrate species and subspecies that seem restricted to mangroves: 48 birds, 14 reptiles, 6 mammals, and 1 amphibian. These include several species with striking adaptations, such as specialized glands to excrete salt. The ground foragers among them feed primarily on crabs, but many of the birds feed on insects. For unclear reasons, mangrove-restricted species and subspecies are concentrated in Asia and Australia.
Between the early 1980s and 2001, between 19 and 35 percent of the world's mangrove forest area was lost. At this rate of loss--about 2 percent each year--mangroves could be extinct in 100 years. Only 27 of the terrestrial vertebrates that are dependent on mangroves have been assessed by the IUCN (International Union for the Conservation of Nature), and 13 of those are classified as threatened on the IUCN Red List, Luther and Greenberg report. They urge research aimed at predicting how continuing changes to mangrove forests are likely to affect the species found there: such information could guide attempts to conserve these specialized ecosystems.
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Mangrove-dependent Animals Globally Threatened
ScienceDaily 1 Jul 09;
Substantial numbers of terrestrial vertebrates are restricted to mangrove forests. Many of these specialized species are listed as threatened by the International Union for the Conservation of Nature. Prospects for mangrove-restricted animals are bleak, because more than two percent of mangrove forests are lost each year.
More than 40 percent of a sample of amphibians, reptiles, mammals, and birds that are restricted to mangrove ecosystems are globally threatened with extinction, according to an assessment published in the July/August issue of BioScience. The study, by David A. Luther of the University of Maryland and Russell Greenberg of the Smithsonian Migratory Bird Center, was based on an extensive literature search and expert consultations.
The conclusions emphasize the vulnerability of animals that are dependent on a habitat rapidly being lost or degraded through coastal development, overexploitation, pollution, and changes in sea level and salinity.
Mangroves, which are salt-tolerant woody plants concentrated along coastal margins, generally in warm regions, have long been known to support many species of animals. Hundreds of vertebrates are sometimes found in mangroves, but Luther and Greenberg concentrated on the 69 terrestrial vertebrate species and subspecies that seem restricted to mangroves: 48 birds, 14 reptiles, 6 mammals, and 1 amphibian. These include several species with striking adaptations, such as specialized glands to excrete salt. The ground foragers among them feed primarily on crabs, but many of the birds feed on insects. For unclear reasons, mangrove-restricted species and subspecies are concentrated in Asia and Australia.
Between the early 1980s and 2001, between 19 and 35 percent of the world's mangrove forest area was lost. At this rate of loss--about 2 percent each year--mangroves could be extinct in 100 years. Only 27 of the terrestrial vertebrates that are dependent on mangroves have been assessed by the IUCN (International Union for the Conservation of Nature), and 13 of those are classified as threatened on the IUCN Red List, Luther and Greenberg report. They urge research aimed at predicting how continuing changes to mangrove forests are likely to affect the species found there: such information could guide attempts to conserve these specialized ecosystems.
Journal reference:
1. David A. Luther and Russell Greenberg. Mangroves: A Global Perspective on the Evolution and Conservation of Their Terrestrial Vertebrates. BioScience, July/August
Adapted from materials provided by American Institute of Biological Sciences, via EurekAlert!, a service of AAAS.
Animals of the Disappearing Mangroves
As mangrove forests shrink worldwide, a menagerie of specially adapted animals that depend on them are at risk, too
Katherine Harmon, Scientific American 3 Jul 09;
In the watery limbo between sea and river, where salt and fresh water mingle in the roots of mangrove trees, a handful of uniquely adapted species—terrestrial and aquatic—have evolved to fill the novel niche.
But more than 40 percent of the land-dwelling animals that live in mangrove forests are now under pressure from habitat loss, concludes an analysis published this week in BioScience.
"Mangroves are threatened by development, pollution, mariculture and changes in sea level and salinity," wrote David Luther, an ecology researcher at the University of Maryland, College Park, and Russell Greenberg, head of the Smithsonian National Zoo's Migratory Bird Center. The impact on creatures that depend on mangroves remains poorly documented.
Tangled woody mangrove forests cover about 65,637 square miles (170,000 square kilometers) around the world, but they're quickly disappearing. A 2007 United Nations report noted that 20 percent of the globe's mangrove forests had vanished in the 25 years between 1980 and 2005, a rate that the U.N. Food and Agriculture Organization's director called "alarming."
Here's a look at the forests and some of the animals that are now threatened by their rapid disappearance.
Slide Show: Vanishing Animals of the Mangroves
