It's hard to imagine this sweet-looking creature with the face of E.T. is 10,000
times more toxic than a slug of cyanide, but so it is.
The orange-bellied,
rough-skinned newt is one of the most poisonous creatures going. The merest bite
creates a severe burning sensation in the mouth.
Every known mammal spits
them out instantly — except men in bars who have been drinking heavily. A
29-year-old from Oregon went into a bar July 9, 1979, and, on a bet, swallowed a
rough-skinned newt. He was dead before the day was out.
No known antidote
exists for a newt's poison, packed by both juveniles and adults in glands in
their skin, and even their eggs.
The poison is tetrodotoxin, or TTX, and is
found in Japanese puffer fish and some species of South American
frogs.
Taricha granulosa, not surprisingly, have no predators, but the
common garter snake is immune to their poison. The newt's deadliest foe is the
automobile.
Newts are slaughtered every spring as they cross roads to head to
their breeding ponds. Habitat destruction is also doing them in. Washington's
amphibians are actually in greater peril than those in any state except
California, Oregon and Nevada. Here, 32 percent of the state's amphibian species
are at risk, a recent Nature Conservancy study found.
Rough-skinned-newt
populations are an exception, so far. They are among the five most-common
amphibians in Washington, and also one of the easiest to find and
identify.
Up to 8 inches long, and lizard-like in appearance, newts could pass
for baby dinosaurs with their rugged, grainy skin, and brontosaurus-like
body.
They are the only salamander that is active above ground, out in the
open and during the day — and slow-footed to boot. Why not, when you are
poison-packed?
Rough-skinned newts belie their name at breeding time, when
the brown, granular skin of the male becomes smooth and supple. The tail also
changes shape, becoming more flat and paddle-like for swimming.
The sight of
newts on the move to the breeding ponds is one of the earliest signs of spring.
The mating season, already under way, kicks off well before Valentine's Day and
extends through April.
Newts are site-faithful, always returning to the same
breeding pond.
Their homing instinct is remarkable: In one experiment, every
newt transported in a light-tight bucket more than a mile from their home pond
found the way back within a year, said Bill Leonard, an endangered-species
biologist for the National Marine Fisheries Service.
Once at the pond, males
patrol the shore for females. So hair-trigger ready are they for breeding that
if a stick is tossed in their path, the males will approach it to see if it is a
mate, said Robert Storm, professor emeritus at Oregon State University.
A
single female approaching the breeding pond can be swarmed by dozens of males,
creating a wiggling wad of newts big as a softball.
Courtship is an elaborate
and lengthy affair.
The male grasps the female behind her front legs and
crawls on her back, locking onto her and holding her tight for hours,
underwater, where the two breathe through their skin.
Afterward, the male
walks in front of his mate — underwater. As he walks along in the shallows, she
follows closely, picking up jellied packets he has left topped with a dollop of
sperm.
She stores the sperm inside her reproductive tract until she lays her
eggs. The fertilized eggs are deposited one at a time on subaquatic
vegetation.
Larvae hatch out within about a month, depending on water
temperature. They emerge equipped with tiny, feathered external gills, giving
them a space-alien appearance. The newts spend the spring and summer swimming
about and chowing down on larvae and other tiny fare.
By August, their
feathered gills have been re-absorbed to tiny nubbins and the newts have grown
lungs and nostrils. They head to the uplands and the forest with the coming of
the autumn rains.
Rough-skinned newts hunt their food, walking the forest
floor and wagging their heads from side to side in search of snails, small
slugs, insects and other invertebrates, which they bag with their sticky
tongues.
Living three to 10 years, newts can be found in surprising density:
Leonard remembers collecting 500 newts in one trap on one night at Fort
Lewis.
\
Kelly McAllister, a biologist with the Washington Department of Fish
and Wildlife, has been monitoring a pond south of Olympia for nearly 10 years.
He has never come back without seeing some newts.
Virginia rails and
blackbirds that share the boggy realm of the newt don't even come near as the
newts swagger about on land, with their all-terrain, hand over hand, four-wheel
amphibian drive. Eat one, and those birds would be dead in 10
minutes.
Scientists have exhaustively examined the newt's astounding
toxicity, learning by force-feeding macerated newt skin to various animals that
a single newt contains enough neurotoxin to keel over 1,500 white
mice.
Scientists have tested 30 potential predators of newts, from belted
kingfishers to great blue herons to bullfrogs and fish, finding in every case
that the newt killed them.
Sometimes the newt crawled unharmed out of the
gasping mouth of the deceased within minutes of being swallowed.
A sample of
the poison had lost none of its potency when examined 11 months after
storage.
Rough-skinned newts are common from the Coast Range near San
Francisco through the entire west side of Washington all the way to Southeast
Alaska. They are found as far east in Washington as Klickitat County. They are
one of the most common amphibians in Western Washington, along with Pacific tree
frogs, red-legged frogs and long-toed salamanders.
Handling them is a treat:
They have soft, smooth skin, sweet faces and delicate, grasping arms and toes.
It's OK to pick them up, but don't mistakenly brush your fingers to your lips or
mouth until you wash your hands thoroughly.
Light as a ballpoint pen, a newt
will rest in the palm, climbing with its forearms up to the index finger to have
a look around. Look it in the eye, and the newt stares right back with a wise
expression, not seeming a bit worried. Placed back on the ground, it walks off
sedately, with a one-bite-and-you're-dead strut.
If startled, newts will
sometimes display a so-called unken reflex: They shut their eyes and arch their
back and tail upward to display a cantaloupe-orange belly. It's a warning to a
potential predator of the newt's toxicity: The combination of a dark-brown,
almost-black back and orange belly is a well-known Mr. Yuk sign in
nature.
For all their toxicity, their appeal is undeniable.
"They are one
of my favorites," said Lynn Havsall, former director of the Camp Long Nature
Center in Seattle. "So beautiful. You just don't want to kiss them."
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