 |
|
Size matters: Preventing large mammal extinction
July 25, 2005Saving large mammals such as elephants and rhino from extinction could be made more effective by focusing efforts on individual species as well as their habitats.
Scientists at the Zoological Society of London's Institute of Zoology (IoZ) and Imperial College London have identified fundamental new approaches to improve the success of large mammal conservation. Published today in the journal Science, the largest study of its kind analyses key factors linked to the extinction of mammals.
"Conservation biologists have always known that large bodied mammals are at greater risk of extinction," comments Professor Georgina Mace of the IoZ, "Now we understand the mechanisms, we are able to tailor conservation programmes dependant on size, to ensure they're more effective."
The study showed that extinction risk in smaller mammals, below approximately 3kg (about the weight of a small domestic cat), is determined primarily by the size and locations of their distributions, and the human impact to which they are exposed. Larger mammals have the additional pressure of biological disadvantages such as long gestation period and late weaning age to contend with, significantly increasing their susceptibility to extinction.
"In a world dominated by people, being big is substantially more of a disadvantage than we realised, which implies that the conservation of large mammals should assume a particular urgency," said Dr Marcel Cardillo of Imperial College London.
"From a conservation policy angle, the message would be: small may be conservable but it is a little trickier for the larger mammals," commented Dr Andy Purvis of Imperial College London.
The research findings suggest smaller species, of around less than 3kg, would benefit from conservation of their habitat area, whereas, larger bodied animals require a different approach, focusing upon the specific species, their biology and their habitat.
"This understanding enables us to predict what species are most at risk in the future," said Dr Purvis. "That provides a way for conservationists to go on the front foot rather than wait for accidents to happen. We can try to work out which species are the ones we can do something for, and do some pre-emptive conservation planning. Of course, prevention is always cheaper than cure."
The research means large bodied mammals such as ungulates (which include rhino and zebra) and many primates are more likely to be predisposed to decline and extinction.
Biological traits such as low population density, slow life history, late weaning age and extended gestation in mammals above a certain size means they are evolutionarily disadvantaged in the face of human impact, compared to species of smaller size. Large mammals may therefore need a more complex conservation strategy, which takes into account their biology in combination with the external threats they face.
Imperial College London
The study showed that extinction risk in smaller mammals, below approximately 3kg (about the weight of a small domestic cat), is determined primarily by the size and locations of their distributions, and the human impact to which they are exposed. Larger mammals have the additional pressure of biological disadvantages such as long gestation period and late weaning age to contend with, significantly increasing their susceptibility to extinction.
"In a world dominated by people, being big is substantially more of a disadvantage than we realised, which implies that the conservation of large mammals should assume a particular urgency," said Dr Marcel Cardillo of Imperial College London.
"From a conservation policy angle, the message would be: small may be conservable but it is a little trickier for the larger mammals," commented Dr Andy Purvis of Imperial College London.
The research findings suggest smaller species, of around less than 3kg, would benefit from conservation of their habitat area, whereas, larger bodied animals require a different approach, focusing upon the specific species, their biology and their habitat.
"This understanding enables us to predict what species are most at risk in the future," said Dr Purvis. "That provides a way for conservationists to go on the front foot rather than wait for accidents to happen. We can try to work out which species are the ones we can do something for, and do some pre-emptive conservation planning. Of course, prevention is always cheaper than cure."
The research means large bodied mammals such as ungulates (which include rhino and zebra) and many primates are more likely to be predisposed to decline and extinction.
Biological traits such as low population density, slow life history, late weaning age and extended gestation in mammals above a certain size means they are evolutionarily disadvantaged in the face of human impact, compared to species of smaller size. Large mammals may therefore need a more complex conservation strategy, which takes into account their biology in combination with the external threats they face.
Imperial College London
Large Mammals Current Events and Large Mammals News RSS10 new amphibian species discovered in Colombia
Scientists today announced the discovery of 10 amphibians believed to be new to science, including a spiky-skinned, orange-legged rain frog, three poison dart frogs and three glass frogs, so called because their transparent skin can reveal internal organs.
Study says eyes evolved for X-Ray vision
The advantage of using two eyes to see the world around us has long been associated solely with our capacity to see in 3-D. Now, a new study from a scientist at Rensselaer Polytechnic Institute has uncovered a truly eye-opening advantage to binocular vision: our ability to see through things.
Dying frogs sign of a biodiversity crisis
Devastating declines of amphibian species around the world are a sign of a biodiversity disaster larger than just frogs, salamanders and their ilk, according to researchers from the University of California, Berkeley.
Clovis-age overkill didn't take out California's flightless sea duck
Clovis-age natives, often noted for overhunting during their brief dominance in a primitive North America, deserve clemency in the case of California's flightless sea duck. New evidence says it took thousands of years for the duck to die out.
New, rare and threatened species discovered in Ghana
Scientists exploring one of the largest remaining blocks of tropical forest in Western Africa discovered significant populations of new, rare and threatened species underscoring the area's high biological diversity and value.
When animals evolve on islands, size doesn't matter
A theory explaining the evolution of giant rodents, miniature elephants, and even miniature humans on islands has been called into questions by new research published today in Proceedings of the Royal Society B: Biological Sciences.
Dead clams tell many tales
Inventories of living and dead organisms could serve as a relatively fast, simple and inexpensive preliminary means of assessing human impact on ecosystems.
Lost forest yields several new species
An expedition led by the Wildlife Conservation Society (WCS) to a remote corner of the eastern Democratic Republic of Congo has uncovered unique forests which, so far, have been found to contain six animal species new to science: a bat, a rodent, two shrews, and two frogs.
Viewing ecosystems from above
"New technology and global observations have improved resource-management decision making from disaster detection and mitigation of fires, insect outbreaks, storms, and floods, to agricultural management and basic ecological research," says Dennis Ojima (Colorado State University).
Ancient DNA traces the woolly mammoth's disappearance
Some ancient-DNA evidence has offered new clues to a very cold case: the disappearance of the last woolly mammoths, one of the most iconic of all Ice Age giants, according to a June 7th report published online in Current Biology, a publication of Cell Press.
More Large Mammals Current Events and Large Mammals News Articles
 |
Long Sleeve T-shirt with chimpanzee, chimp, monkey, mammal, animal Large White by Shop Zeus |
 |
Large Mammal Restoration: Ecological And Sociological Challenges In The 21St Century by David Maehr (Editor), Reed F. Noss (Editor), Jeffery L. Larkin (Editor), Melvin E. Sunquist (Editor) Evidence is mounting that top carnivores and other large mammals play a pivotal role in regulating ecosystem health and function, yet those are the species that are most likely to have been eliminated by past human activities. In recent decades, numerous efforts have been undertaken to return some of the species that were previously extirpated on local or regional scales. Large Mammal Restoration brings together for the first time detailed case studies of those efforts, from restoring elk in Appalachia to returning bison herds to the Great Plains to the much- publicized effort to bring back the gray wolf to Yellowstone National Park. Together these case studies offer important lessons and new ways of thinking for wildlife managers and conservation biologists involved with restoration... |
 |
Blue Whale Spouting Animal - WATCHBUDDY® DELUXE TWO-TONE THEME WATCH - Arabic Numbers - Black Leather Strap-Size-Large ( Men's Size or Jumbo Women's Size ) by WatchBuddy Timepieces WatchBuddy Deluxe Watches are the World's Most Lovable Theme Watches, they combine beauty, style and grace with functionality. The watch has a precision quartz crystal movement with three (golden) hands - hour, minute and second. The watch case is high gloss two-tone metal. The case back is stainless steel and laser engraved. The strap (or band) is leather with metal buckle and is available in four different colors - black, brown, blue & green. The watch is water resistant to 3 ATM or 100 feet. Battery life is 2 years. Watches have a one year limited warranty. Watches come in two sizes (see link for size chart): - Large Size: for standard men's or jumbo women's size - suitable for wrists between 6.7 inches and 8.27 inches (17 cm and 21 cm). Case dimensions - Diameter: 1.44 inches (3.4... |
 |
Marchioro (Tommy A) Small Mammal Cage -Extra Large by Marchioro Made of light weight and durable plastic with a sturdy metal cage top, the Tommy K cage is a fantastic home for your family pet. |
 |
Nature Wonders NAKURU Kenya Directed By: TravelVideoStore.com Also With: TravelVideoStore.com (Producer) |
 |
Plush Daily Grind Walbert Walrus 9.5" by Gund |
 |
Many Pieces of Large Fuzzy Mammals Gathered Together at a Rave and Schmoozing With a Brick Man Or Astroman? (Primary Contributor) |
 |
Long Sleeve T-shirt with whale, ocean, marine, mammal, animal, fin Large White by Shop Zeus |
 |
Large Dolphin Earrings by Wildthings Sterling silver with hook back. Please allow 5 business days to process an order including this item. Your shipping option will determine delivery time once it ships. |
 |
Onesie with whale, ocean, humpback, animal, large, sea, mammal by Shop Zeus |
| © 2009 BrightSurf.com |