Sedgwick Zoo Hatches 2nd Komodo Dragon

The Sedgwick County Zoo has become the first zoo in the Americas to document that Komodo dragons are capable of parthenogenesis (reproduction without the contribution of a male).

One Komodo dragon entered the world on January 31 and a second hatched on February 1, 2008 thanks to this type of asexual reproduction.

Parthenogenesis is a reproductive process that occurs naturally in some species including invertebrates, lower plants, and less commonly in vertebrates such as reptiles and fish. A parthenogenetic egg needs no fertilization from a male because it inherits and duplicates the mother’s chromosome. Based on a Komodo dragon’s genetics of sex determination, hatchlings reproduced in this way will always be male.

The hatchlings are healthy and feisty, the first measuring almost 17 inches long from nose to tail and weighing 104 grams and the second hatchling measuring 16 inches long and weighing 100 grams. Both males are doing well. Because of the nature of Komodo dragons, only one will be on exhibit at a time starting today, February 6, in the Amphibian and Reptile Building.

Sedgwick County Zoo has two adult Komodo dragons; both are female and cared for separately. One female laid approximately 17 eggs on May 19-20, 2007 and Zoo staff followed the Species Survival Plan (SSP) recommendation to incubate and hatch two eggs. The SSP wanted to further document that Komodo dragons are capable of parthenogenesis. Only two earlier cases were documented in 2006 at London Zoo and Chester Zoo in England.

         

From wibw.com

Crocodiles at risk from cane toad march

CANE toads are threatening to wipe out a rare pygmy crocodile found in only two places in the Northern Territory.

The marauding toads may have already wiped out the small collection of pygmy crocs in Arnhem Land – and a billabong close to the Western Australian border is the next and final battlefront.

There the unique breed of tiny reptiles will make their last stand, and according to environmentalists, probably meet their demise.

About 10 dead freshwater crocodiles have been found floating belly up at a remote billabong near the WA border, only 20km from the body of water which their smaller cousins call home.

“The crocodiles lie dead on the bottom for a couple of days until they roll over and float to the top … an autopsy found their bellies were full of cane toads,” said Sandy Boulter, from a toad busting organisation attempting to halt the spread of the feral pests.

“This fate awaits the rare Bullo River Station pygmy crocodile … It doesn’t matter the size of the animal, the toxin of the cane toad will kill all of our Australian fauna.

“No sooner has this rare crocodile species been discovered on Bullo, the feral, prolific breeding, and very poisonous cane toad is about to arrive.”

Since being introduced to Queensland in the 1930s, cane toads have spread across northern Australia.

They have already ravaged the world heritage-listed Kakadu National Park, killing everything and anything that eats them, from crocodiles to quolls, as they move north to Darwin.

Crocodile specialist Adam Britton said the tiny reptiles, which grow up to 1.5m in length and fronted the first wave of the toads a few years ago, may already be extinct in Arnhem Land.

“This is the only population that we know of at the moment that hasn’t been affected by cane toads,” he said, referring to the Bullo Station population.

“You’re talking about what could be a genetically distinct pygmy crocodile. I mean, that’s pretty special. You don’t want to lose that kind of resource.”

Mr Britton has applied for a permit to collect tissue samples for testing, while environmentalists have called on the NT government for financial assistance.

But NT Parks and Wildlife Minister Len Kiely said large sums of money were already being spent on the battle against cane toads.

“Cane toads are an invasive species and we are looking at tackling those in all manners and all ways,” he told the ABC.

From news.com.au