Thursday, April 29, 2010
Nature Notes - The Irish Frog
Visit Michelle at the informative Nature Notes Thursday to learn something new.
Today we're going to learn about Irish frogs. The Irish have deep roots in American history, so today is a cross-cultural, Nature Notes, natural world, biology bonanza!
Let's get started: There are three types of amphibians in Ireland. The Amphibians are divided into three groups: the Urodela (newts and salamanders), the Apoda (worm-like caecilians), and the Anura (frogs and toads). The Anura (meaning tail-less) are the largest and most widely distributed amphibian group with over 3,500 species worldwide.
There are three species of amphibian found in Ireland - the Natterjack Toad (Bufo calamita), the Smooth Newt (Triturus vulgaris) and the Common Frog (Rana temporaria).
The Irish word for frog is frog. Try it out and see how it sounds at TalkIrish.
The Common Frog, Rana temporaria Loscán, is the only frog in Ireland and it is protected because the population of frogs in Europe is declining, much like the frog populations elsewhere. Frog problems are a worldwide issue, not just a problem in the United States.
The Irish frog spends most of its adult life in water and spawns in shallow water using ponds for breeding and living in damp woodland farmland or peatland. They are widespread over the country, not spending more time in one location more than another.
Their cousin the Natterjack Toad is different. They live in Kerry and Wexford and don't get around much. Kerry is in the southwest end of Ireland and Wexford is on the coast on the eastern coast of southern Ireland across the water from Wales.
Anyway, the common frog in Ireland mates in January and later lays 4,000 eggs at a time which are then fertilized externally by the male. They are 60-80 mm long, which is almost 2.5 inches to barely over 3 inches. Lastly, the Irish frog has a diet of flying insects, beetles, slugs & snails.
Here is a special note about Irish frogs: they are genetically Irish and different from their British friends. Here is some information about their lineage from a press release on recent research. This was released in March 2009.
Irish frogs are Irish
Recent evidence has shown that Ireland's frogs differ from those of mainland Britain, shedding new light onto where frogs disappeared to when the Ice Age hit Europe over 10,000 years ago.
Research by scientists at the Zoological Society of London (ZSL) and Queen Mary, University of London suggests that some of the ancestors of Ireland's frogs survived the Ice Age, whereas those in the rest of the British mainland retreated, later to be re-populated by frogs from mainland Europe once the Ice Age was over.
Ice free refuge in Ireland
The paper, in the journal Heredity, suggests that a small ice-free refuge may have existed in Ireland during the Ice Age, and here amphibians may have been able to see out the worst of the cold and ice. Scientists found genetic differences between Common Frogs (Rana temporaria) in mainland Britain and those of mainland Ireland while undertaking research into amphibian disease.
Lead author Dr Amber Teacher, from ZSL, said: "It appears that some frogs may have survived through the glaciations in this ice-free part of Ireland, as there is a distinct genetic lineage found in the South of Ireland that is not found elsewhere in Europe."
"So within Ireland, we can find frogs that originate from this small part of southern Ireland, mixed with the frogs that came from Western Europe to repopulate the British Isles after the ice age retreated."
The work was undertaken with the help of the Irish Peatlands Conservation Council and Froglife, a UK wildlife charity for amphibians and reptiles.
"This study has given us a unique and fascinating window into the history of frogs in the UK." said Lucy Benyon, Froglife's Wildlife Information Officer.