Ah sweet, blessed rain, the gage at my house said 4 inches. This beautiful weather brings out some of my favorite critters… the newts. In between storms last Friday night I took some folks on a night hike at Muir Beach. Newts were everywhere. In fact it was difficult to walk at times, there were hundreds of them and 90% were munching on earthworms. Some of the newts were totally obese and one I picked up actually threw up an earthworm in my hand….gross. We saw several pairs of newts fighting over the same worm. It was a game of tug of worm and the worm lost every time.

Newts (and salamanders) are distinguished from lizards by their clawless feet, lack of ear openings and moist rather than scaly skin. They are slow and easy to catch. Two species are found here — the California and the Rough skinned Newt. Both have backs that are deep red brown, almost black and an underside of pale yellow to startling orange or even red. The skin is rough and warty and becomes more so the longer the animal is out of the water.

This skin contains a poison called tetrodotoxin, the same chemical found in puffer fish. The bright underside of the animal advertises its toxicity. The only animals I know that can survive eating a newt are feral pigs. The newts average 2 3 inches between the front and back legs (about 6 inches overall) and are often found far from permanent water during the rainy season. They feed on earthworms, snails, insects, slugs, spiders, sowbugs, and will occasionally scavenge.

Male newts are easily distinguished from females. Pick up the animal it won’t bite you, but be sure to wash your hands afterwards and turn it over. The feet of the males are usually roughened, enabling it to grasp the slippery female as they mate.

Look between the rear legs at the vent. If the area is swollen, it is male. This swelling is caused by the presence of a spermatophore, a package of sperm. After an elaborate, stereotyped courtship ritual that involves much clasping, piggy back riding and the inhibition of female movement by special skin glands in the chin of the male, the act culminates with the male walking over the top of the female and depositing the package of sperm right in front of her nose.

She promptly walks over the “gift” and picks it up with her vent. She stores the sperm and uses it later to fertilize her eggs when she deposits them on submerges vegetation in a stream.

Newts are amphibians, one of the oldest vertebrate groups. This group apparently evolved from the lobe finned fishes that were trapped in temporary fresh water ponds around 350 million years ago. Fins became walking appendages facilitating movement from drying pond to drying pond and lungs replaced gills as a mechanism for oxygen extraction. Unlike their descendants, the reptiles, amphibians have failed to sever their ties with water.

Indeed the word, amphibian, literally means “double” (amphi) “lives” (bios). Two lives — one in water and one on land. It is always necessary for these animals to return to water (or very moist areas) to lay their eggs.

Because the skin is permeable to water and can dry out very rapidly, amphibians are restricted to damp areas and cannot live in salt water. Understandably the arid West has fewer species that the wetter East. Still, they are distributed throughout the world except for the polar areas and some oceanic islands. Even deserts support some species adapted to seasonal rains. They escape the searing heat by digging deep into the earth.

California has 25 kinds of salamanders and 20 kinds of frogs and toads. In Marin County, the roster includes: the Western Toad, Red legged Frog, Foothill Yellow legged Frog, Bullfrog, Pacific Tree Frog, Pacific Giant Salamander, Ensatina Salamander, California Slender Salamander, Arboreal Salamander and our two newts.

So where do I get most of my information? From the newts-paper, of course. What do you call it when two newts mate? For-newt-cating. One of my least favorite entertainers is Wayne Newt-on. Favorite football player is Newt Rockne. Most of you probably agree that my mind must be in newt-tral to write this stuff.

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August 6, 2009