Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Could Global Warming Be Crushing Blow to Crocodiles?

27.11.2006
Rising temperatures may disrupt gender balance among reptile populations, says Earthwatch-supported crocodile researcher Dr. Alison Leslie of University of Stellenbosch. Her comments came during the filming of A Year on Earth, premiering this week on Discovery Kids Channel.

With global temperatures generally on the rise, crocodiles may have a harder time finding mates. For crocodiles, gender is not determined genetically, but rather by embryo temperature during incubation, notes Earthwatch-supported scientist Dr. Alison Leslie, of South Africa’s University of Stellenbosch.

In an interview with three teenagers on a mission to find out about their planet, the subject of the new film A Year on Earth, Leslie explained how global warming could affect crocodile populations worldwide.

“A difference of 0.5 - 1ºC in incubation temperature results in markedly different sex ratios,” says Leslie, principal investigator of Earthwatch’s Crocodiles of the Okavango Delta project. Research shows that nest temperatures of about 32-33 degrees Celsius result in males, while temperatures higher and lower result in females. Temperatures within a nest can vary from the top to the bottom of the nest, and can result in mixed-gender hatchlings.

“More female hatchlings due to the cooler or hotter incubation temperatures could lead to eventual extirpation of the species from an area,” says Leslie.

The three teens, Jamie (18), Arsen (17), and Tyler (16), visited Leslie at her camp in the Okavango Delta, Botswana, where they acted as field research assistants on Leslie’s Earthwatch-supported research expedition. Their participation was part of a feature-length documentary, A Year on Earth, that will air on the Discovery Kids Channel in December.

The teens helped Leslie trap and examine Nile crocodiles big and small to monitor their diet, health, movements, and reproductive biology. Crocodile populations have dwindled dramatically in Botswana, due to overexploitation by hide hunters and conflicts with nearby communities.

“Even though crocodilians have been around for millions of years, and as important as these creatures may be in the systems they occupy, they are a much understudied species,” says Leslie. For more than eight years, in both Botswana and South Africa, Leslie has been working with the support of Earthwatch Institute to change that.

In 2007, Leslie will leave behind her Okavango research camp (in the capable hands of staff member Sven Bourquin), and will embark on a new study of the crocodiles along Zambia’s Zambezi River. Earthwatch volunteers will continue to assist her as she assesses the conservation needs of this population and surveys local villagers about crocodile impacts.

Earthwatch Institute is a global volunteer organization that supports scientific field research by offering members of the public unique opportunities to work alongside leading field scientists and researchers. Earthwatch's mission is to engage people worldwide in scientific field research and education to promote the understanding and action necessary for a sustainable environment. The year 2006 marks Earthwatch's 35th anniversary.

See Dr. Alison Leslie in A Year on Earth, a two-part special to debut on Discovery Kids Channel on December 3 and 10. A Year on Earth chronicles the work of three American teens who join Leslie in the Okavango Delta and several other Earthwatch research projects around the world. Together, they discover how ordinary people can make a difference in the most pressing environmental issues of our time.

Delta Willis | newswise
Further information:
http://www.earthwatch.org/pubaffairs/fieldnews.html

More articles from Ecology, The Environment and Conservation:

nachricht A new indicator for marine ecosystem changes: the diatom/dinoflagellate index
21.08.2017 | Leibniz-Institut für Ostseeforschung Warnemünde

nachricht Value from wastewater
16.08.2017 | Hochschule Landshut

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Nagoya physicists resolve long-standing mystery of structure-less transition

21.08.2017 | Materials Sciences

Chronic stress induces fatal organ dysfunctions via a new neural circuit

21.08.2017 | Health and Medicine

Scientists from the MSU studied new liquid-crystalline photochrom

21.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>