Biology Reference
In-Depth Information
age and wander about. The number of them at such times is quite astonishing, considering that a walk
through the same area before the rain would reveal nary an eft!
The color of the eft's dry, slightly pebbly skin is quite variable. Many efts are a bright red that stands
out like a beacon against the rather dull colors of the forest floor. Others are an orange that's nearly as
bright, but still others are of varying lesser intensities of red and orange, all the way down to a sort of
dusky reddish brown. In common with the adult newt, however, they all have little black spots and the
larger black-ringed red spots along both sides of the back.
At first glance, the bright color of the efts might seem to work to their disadvantage by making them
more visible to predators, but efts are to some degree toxic—though not for humans to handle—and
scientists speculate that their bright color may serve as a warning to predators that they should be left
alone.
The time that efts spend in this intermediate, terrestrial stage is as variable as their color. At least
two years, but sometimes as many as seven, elapse before they begin to assume the form of the adult
newt. This transformation takes place over several months, and the efts, now sexually mature, migrate
back to water. There they develop the fully adult form, including the keeled tail. This migration back to
water can occur any time during the warmer months.
The eft can be regarded as a wonderful adaptation that greatly increases the chances of the newt's
survival. Because it's terrestrial, the eft stage allows newts to breed in ponds that at least occasionally
dry up by late summer or early autumn, thereby eliminating fish, one of their most important predators.
Even if waters that are generally more permanent dry up in a lengthy and extreme drought, the efts will
survive to return to water somewhere and perpetuate the species.
The aquatic adult newts feed on all sorts of insect larvae, especially those of mosquitoes and midges.
Thus they're valuable from a human perspective by controlling many ferocious little insects that love
to sip our blood. Newts also eat a wide variety of insect nymphs, adult insects, snails, eggs of frogs and
toads, and even the larvae of their own species.
In winter, adult newts hibernate either underwater or on land beneath objects such as logs. However,
some remain active all winter beneath the ice. Efts also hibernate during their years on land. They bur-
row beneath the leaves or other litter on the forest floor, or crawl beneath logs and other objects that
offer shelter for the winter.
This account doesn't quite complete the tale of this rather strange and very interesting little creature,
however. As previously mentioned, some newts skip the eft stage entirely. These individuals, known as
neotenes,
pass directly from the larval to the adult stage without ever leaving the water. In the process,
they retain such larval characteristics as external gills, although these may be substantially smaller than
the gills on a normal newt larva. It's uncertain why some newts become neotenes—one more mystery
in the incredibly complex world of nature.
Although newts are fortunately a very long way from being an endangered species, they can suffer
locally from an increasing number of highways that interfere with the outward migration of efts and
