Wednesday, October 14, 2009

The Three Lives of the Eastern Newt

By Heather Lunn, Senior Interpreter
(Photo by Simon Lunn )

Like many other species of salamanders, eastern newts begin their lives as eggs laid in springtime in small forest ponds. They hatch in late spring and spend the first two or three months of their lives in the water as a larval newt with finned tails and gills. Around August and September, however, many of these baby newts have developed lungs, lost their gills, their tails have become rounded, and they have had their slimy brown skin change to rough, bright red or orange in colouration! They emerge from the water onto land into their next stage of life where they are known as a “red eft.” The eft stage for a newt makes them unique among salamanders. For other salamanders, once they emerge onto land from their pool of origin they are ready to begin their adult lives. However, for the eastern newt, their land-loving, red-eft stage is their time to be a teenager, and they will eventually return to the water permanently as an adult newt.

As a prepubescent newt, the terrestrial red eft will wander around in daylight, in rainy weather, more often than other salamanders. This may seem unwise given the eft’s bright red- and orange-coloured skin, which stands out against the brown of the forest floor. Their colouration is an advertisement, however, to any would-be predators that the eft is to some degree toxic and would not be very palatable to eat. At 3 to 10 cm in length, red efts often evade our eyes, even with their bright colouration. They spend much of their time under rotting logs during the day and wander around mainly at night hunting for insects, larvae, snails, and worms.

Newts will stay in their red-eft stage from two to seven years. While in this form, they over-winter in similar haunts as other salamanders, such as under rocks, logs, and banks below the frost line. Finally one spring the red eft will receive the calling to go back to the water. As they become a sexually mature adult eastern newt, their skin loses its rough feeling and becomes soft and moist again. The bright orange and red colouration changes to a more easily camouflaged olive green. Lastly, as they head back to the water, their tails become keeled again. Unlike frogs, toads, and some other salamanders, newts are not drawn back to their ancestral pond to mate. The efts will travel overland to new ponds, which promotes cross-breeding between different populations. Their entire lifespan, from egg to larva to eft to newt, can take up to 15 years. After changing into their final adult newt form, they rarely ever set foot on land again, except occasionally to hibernate. If their water pool dries up, newts will sometimes change colour to brown, loose their keeling on their tail and go in search of a new watery home.

Harding, James H. (2006). Amphibians and Reptiles of the Great Lakes Region. The University of Michigan Press: United States of America.

MacCulloch, Ross D. (2002). The ROM Field Guide to Amphibians and Reptiles of Ontario. Royal Ontario Museum: Toronto.

Shedd, Warner (2000). Owls Aren’t Wise and Bats Aren’t Blind. Three Rivers Press: New York.

Bennet, Doug; Tiner, Tim (1993). Up North. Reed Books Canada: Toronto.

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