Featured Research

from universities, journals, and other organizations

Wild Cuban crocodiles hybridize with American crocs

Date:
June 22, 2011
Source:
Wildlife Conservation Society
Summary:
A new genetic study confirms that American crocodiles are hybridizing with wild populations of critically endangered Cuban crocodiles, which may cause a population decline of this species found only in the Cuban Archipelago.

A new study confirms that critically endangered Cuban crocodiles are hyrbridizing with American crocodiles in the wild.
Credit: Steve Zack/Wildlife Conservation Society

A new genetic study by a team of Cuban and American researchers confirms that American crocodiles are hybridizing with wild populations of critically endangered Cuban crocodiles, which may cause a population decline of this species found only in the Cuban Archipelago.

Cuban crocodiles and American crocodiles have been confirmed to interbreed in captivity and were suspected to hybridize in the wild. This is the first genetic study that confirms wild hybridization.

The study, which appears in the April 2011 issue of the Journal of Experimental Zoology, is by Yoamel Milián-García of the University of Havana; Miryam Venegas-Anaya of the Smithsonian Tropical Research Institute; Roberto Frias-Soler of the University of Havana; Andrew Crawford of the Smithsonian Tropical Research Institute; Roberto Ramos-Targarona, Roberto Rodríguez-Soberón, and Manuel Alonso-Tabet of Empresa Nacional para la Protección de la Flora y la Fauna; the late John Thorbjarnarson of the Wildlife Conservation Society; Oris I. Sanjur of the Smithsonian Tropical Research Institute; Georgina Espinosa-López of the University of Havana; and Eldredge Bermingham of the Smithsonian Tropical Research Institute.

Known for their leaping ability and aggressive disposition, Cuban crocs are a charismatic and culturally significant species to Cuba. Exact population estimates for the species remain unknown, though scientists believe that a minimum of 3,000 individuals remain in the Zapata swamp. A smaller population exists in the Lanier Swamp on the Island of Youth. The species was extensively hunted from the middle of the 19th century through the 1960s resulting in drastic population declines.

The team collected and analyzed DNA from 89 wild-caught Cuban and American crocodiles in the wild and two samples from crocodiles in zoos.

The genetic data produced an unsuspected result: American crocodiles in Cuba are more closely related to Cuban crocodiles than other American crocodile populations found along mainland Central America. The study found just a 1 percent genetic sequence divergence between Cuban crocodiles and American crocodiles in Cuba yet an 8 percent divergence between American crocodiles in Cuba and other American crocodile populations living in mainland Central America.

This finding indicates that Cuban crocodiles and American crocodiles in Cuba may represent two evolutionary significant units (ESU's) -- populations considered distinct for conservation purposes and represent an important component of the evolutionary legacy of the species.

The team collected and analyzed DNA from 89 wild-caught Cuban and American crocodiles in the wild and two samples from crocodiles in zoos.

The authors say that hybridization may be one of the most important threats to Cuban crocodiles, along with illegal hunting and habitat modification. Hybridization can result in both replacement and genetic mixing, and one lineage may cause the extinction of another.

Based on evidence of hybridization between the two species, the authors strongly urge that efforts to avoid anthropogenic causes of hybridization be taken into account for future management plans of Cuban crocodiles.

The authors acknowledge the following: Faculty of Biology, University of Havana, Cuba; Marine Research Centre, Havana, Cuba; National Enterprise for the Conservation of Flora and Fauna, Cuba; Smithsonian Tropical Research Institute, Panama, Republic of Panama.

WCS is grateful to the John D. and Catherine T. MacArthur Foundation and the Christopher Reynolds Foundation for supporting critical conservation work in Cuba.


Story Source:

The above story is based on materials provided by Wildlife Conservation Society. Note: Materials may be edited for content and length.


Journal Reference:

  1. Yoamel Milián-García, Miryam Venegas-Anaya, Roberto Frias-Soler, Andrew J. Crawford, Roberto Ramos-Targarona, Roberto Rodríguez-Soberón, Manuel Alonso-Tabet, John Thorbjarnarson, Oris I. Sanjur, Georgina Espinosa-López, Eldredge Bermingham. Evolutionary history of Cuban crocodiles Crocodylus rhombifer and Crocodylus acutus inferred from multilocus markers. Journal of Experimental Zoology Part A: Ecological Genetics and Physiology, 2011; 315A (6): 358 DOI: 10.1002/jez.683

Cite This Page:

Wildlife Conservation Society. "Wild Cuban crocodiles hybridize with American crocs." ScienceDaily. ScienceDaily, 22 June 2011. <www.sciencedaily.com/releases/2011/06/110622115313.htm>.
Wildlife Conservation Society. (2011, June 22). Wild Cuban crocodiles hybridize with American crocs. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2011/06/110622115313.htm
Wildlife Conservation Society. "Wild Cuban crocodiles hybridize with American crocs." ScienceDaily. www.sciencedaily.com/releases/2011/06/110622115313.htm (accessed July 28, 2014).

Share This




More Plants & Animals News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) — A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
Powered by NewsLook.com
Trees Could Save More Than 850 Lives Each Year

Trees Could Save More Than 850 Lives Each Year

Newsy (July 27, 2014) — A national study conducted by the USDA Forest Service found that trees collectively save more than 850 lives on an annual basis. Video provided by Newsy
Powered by NewsLook.com
What's To Blame For Worst Ebola Outbreak In History?

What's To Blame For Worst Ebola Outbreak In History?

Newsy (July 27, 2014) — A U.S. doctor has tested positive for the deadly Ebola virus, as the worst-ever outbreak continues to grow. Video provided by Newsy
Powered by NewsLook.com
The New York Times Backs Pot Legalization

The New York Times Backs Pot Legalization

Newsy (July 27, 2014) — The New York Times has officially endorsed the legalization of marijuana, but why now, and to what end? Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins