Navigation Links
Study shows 'dinosaurs of the turtle world' at risk in Southeast rivers
Date:4/10/2014

GAINESVILLE, Fla. --- Conservation of coastal rivers of the northern Gulf of Mexico is vital to the survival of the alligator snapping turtle, including two recently discovered species, University of Florida scientists say.

A new study appearing this week in the journal Zootaxa shows the alligator snapping turtle, the largest freshwater turtle in the Western Hemisphere and previously believed to be one species, is actually three separate species.

The limited distribution of the species, known to weigh as much 200 pounds, could potentially affect the conservation of rivers the turtles inhabit, including the Suwannee, said lead author Travis Thomas, a Florida Fish and Wildlife Commission scientist and former Florida Museum of Natural History volunteer who began the research as a UF wildlife ecology and conservation student.

"We have to be especially careful with our management of the Suwannee River species because this turtle exists only in that river and its tributaries," Thomas said. "If something catastrophic were to occur, such as a chemical spill or something that affects the entire river, it could potentially devastate this species. The turtle is extremely limited by its habitat. All it has is this river and it has nowhere else to go."

In the study, scientists revised the genus Macrochelys, often called the "dinosaurs of the turtle world" by lay people, to include Macrochelys temminkii and the two new species, Macrochelys apalachicolae and Macrochelys suwanniensis. Restricted to river systems that drain into the northern Gulf of Mexico, the species are divided by geography, which led to differences in genetics, said co-author Kenneth Krysko, a herpetologist with the Florida Museum on the UF campus.

"M. temminkii is found in river drainages such as the Mississippi and Mobile, while M. apalachicolae is confined to the Apalachicola and other Panhandle rivers," Krykso said. "There are no alligator snapping turtles in the seven rivers between the Suwannee and Ochlockonee (Aucilla, Econfina, Fenholloway, Saint Marks, Steinhatchee, Wacissa and Wakulla). This gap creates a geographic isolation that has likely resulted in the Suwannee species being the most genetically and morphologically distinct of the three Macrochelys lineages."

These turtles were heavily harvested in the past for human consumption, which decimated populations from Texas to Florida, in part because of the species' low offspring survival rate.

Florida Fish and Wildlife surveys of the Suwannee River during the past three years show M. suwanniensis populations are higher than previously believed. Thomas said the species' survival remains a concern due to its restricted range and Florida law prohibits the possession, capture and pursuit of alligator snapping turtles.

"We hope the new study leads to greater conservation efforts and management plans customized to protect each individual species," Thomas said. "The key to conserving these species is to protect their habitats. If we protect the rivers, that is the biggest step toward protecting the wildlife that depend on them, especially in the case of the Suwannee species."

In the study, researchers examined the fossil record from 15-16 million years ago to the present and found morphological and genetic variations among the three species. Distinct variations were documented in the carapace, or shell, which can be easily observed in both living and fossil specimens.

"The western group (M. temminckii) is morphologically more primitive, but genetics testing suggests that the Suwannee snapper has a deeper divergence," said study co-author Jason Bourque, a vertebrate paleontologist with the Florida Museum of Natural History, "When alligator snappers show up in the fossil record, they look a lot like modern alligator snappers. They do not start showing up in the fossil record until the early Miocene, but snapping turtles as a group go back to the late Cretaceous."

With their spiked shells and scaled bodies, the prehistoric-looking reptiles can live up to nearly 100 years, but it is their amazing size that has drawn peoples' attention for centuries, Thomas said. As large, apex predators, alligator snappers play an important role in the wild. A river ecosystem deprived of its alligator snappers would most likely experience negative implications, Thomas said.

The study's value to conservation biology and other taxonomic studies is invaluable, said John Iverson, a biologist with Earlham College not associated with this research.

"We can finally begin to manage these three genetic units separately and appropriately," Iverson said. "The incredibly detailed work of these researchers in bringing together the genetic, morphological, ecological, zoogeographic and paleontological data to clarify the relationships among the three alligator snapping turtle species should be emulated by other systematists and conservation biologists."


'/>"/>

Contact: Kenneth Krysko
kenneyk@flmnh.ufl.edu
352-273-1945
University of Florida
Source:Eurekalert

Related biology news :

1. Study by UC Santa Barbara researchers suggests that bacteria communicate by touch
2. Law that regulates shark fishery is too liberal: UBC study
3. New study will help protect vulnerable birds from impacts of climate change
4. Study jointly led by UCSB researcher supports theory of extraterrestrial impact
5. BYU study: Using a gun in bear encounters doesnt make you safer
6. 15-year study: When it comes to creating wetlands, Mother Nature is in charge
7. Pycnogenol (French maritime pine bark extract) shown to improve menopause symptoms in new study
8. Crystal structure of archael chromatin clarified in new study
9. EU-funded study underlines importance of Congo Basin for global climate and biodiversity
10. University of Houston study shows BP oil spill hurt marshes, but recovery possible
11. Study demonstrates cells can acquire new functions through transcriptional regulatory network
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/2/2016)... NEW YORK , Feb. 2, 2016 ... healthcare facilities are primarily focused on medical ... that measure point-of-care parameters. Wearable devices that ... a user,s freedom of movement are being ... sensors for human biomedical signal acquisition coupled ...
(Date:2/2/2016)... Feb. 2, 2016   Parabon NanoLabs ... U.S. Army Research Office and the Defense Forensics ... sensitivity of the company,s Snapshot Kinship Inference ... and, more generally, defense-related DNA forensics.  Although Snapshot ... (predicting appearance and ancestry from DNA evidence), it ...
(Date:2/1/2016)... , Feb. 1, 2016  Wocket® smart wallet ( www.wocketwallet.com ) announces ... personality, Joey Fatone . Las Vegas , ... --> Las Vegas , where Joey appeared ... The new video ad was filmed at the Consumer Electronics Show ... the Wocket booth to meet and greet fans. ...
Breaking Biology News(10 mins):
(Date:2/3/2016)... , ... February 03, 2016 , ... ... Linux and Unix visualization solutions today announced the addition of a powerful “Session ... users to see the current state of the remote Linux desktop or other ...
(Date:2/3/2016)... Therapeutics, Inc., today announced the closing of a $6 million ... total of $10.25 million in Series A funding based on ... was led by existing investor The Kraft Group of ... Lear Corporation and Highland Consumer Partners, as well as existing ... Sackler , MD, with Summer Road, LLC; Erin Donohue ...
(Date:2/3/2016)... , ... February 03, 2016 , ... ... to aid in the rapid development and ongoing quality control of molecular assays ... outbreak is extremely high,” Dr. Gregory R. Chiklis, President and CEO of ZeptoMetrix, ...
(Date:2/3/2016)... ... 03, 2016 , ... Marktech Optoelectronics, a leading supplier of ... epi wafers based in Latham, New York, offers a wide variety of ... Si and InGaAs PIN photodiodes. But it is Marktech's newly enhanced capability to ...
Breaking Biology Technology: