Spotted Tussock Moth (Lophocampa maculata)
Spotted Tussock Moth Caterpillar
Credit: Terry Thormin
Spotted Tussock Moth
Credit: Terry Thormin
The caterpillar of the Spotted Tussock Moth is often called
the Yellow Woolly Bear. This is a caterpillar that is often seen
crawling around on the ground in the fall, looking for an appropriate
place to pupate.
This distinctive looking caterpillar is quite hairy and banded black,
yellow and black. It also has long white hair tufts at each end. In
eastern North America, the caterpillar has a row of about four black
spots in the central yellow area running right down the middle of the
back. These spots seem to be missing in the Alberta population, and
perhaps in other western populations. There is also a population in
California where the yellow is replaced by orange. The adult moth has
yellow-brown front wings with lighter yellowish spots, and pale yellow
hind wings. Moths from California have the front wings heavily marbled
with darker brown markings. Caterpillars grow to about 4 cm long and
the adult moths can have a wingspan of up to 4.5 cm.
This species is found throughout Alberta, and even into the North West Territories.
It is found from the maritime provinces west into British Columbia and
south into the mountains of North Carolina and west to southern California.
TIME OF YEAR
In Alberta adults are flying in June and July. The first caterpillars
are out by early August and last well into September. This species over-winters as pupae.
HABITAT AND HABITS
Caterpillars feed on a wide variety of trees including poplars, birches,
maples, willows and oaks. They are most often seen when they come down
out of the trees and go looking for a sheltered place to pupate. Adult
moths are nocturnal (active at night) and fly in forested and brushy areas.
They are sometimes attracted to lights.
The Woolly Bear caterpillar is the larva of the Isabella Moth (Pyrrharctia isabella).
It is rather similar to the caterpillar of the Spotted Tussock Moth, but
the yellow is replaced by reddish brown and it lacks the long white hair tufts.
This common caterpillar is distinctive enough so that once people see it, they
are often curious to know what it is. This species is never abundant enough
to be a serious pest. Caution should be used if you plan on handling this
caterpillar because it has urticating (irritating) hairs to which some
people are allergic. The moth is so drab that it is seldom noticed.