The lives and travels of opossums

VIC LEIPZIG AND LOU MURRAY

With their rat-like tails, dark eyes and long, pointy noses, opossums

are not endearing to most people. But relative beauty is not the

issue. How they got here is.

Vic and I were looking at the range map of the Virginia opossum

the other day and noted something odd. Opossums range throughout the

eastern half of the United States, the Great Plains, the Gulf states

and down into eastern Mexico and Central America. An isolated

population is found on the West Coast, from British Columbia down to

San Diego. There is a big gap on the range map between the eastern

and western populations.

Opossums like to live in deciduous forests and on prairies. They

do well in suburban areas. They don’t live in deserts or the

mountains. If they walked to California, they would have had to cross

some forbidding territory.

In fact, they didn’t cross those deserts and mountains by

themselves. It turns out that someone brought them to California and

released them around San Jose in 1895. Possum fur isn’t thought to be

very attractive, thus it’s not valuable, so presumably they were

introduced merely for the sport of hunting. We’re not sure why anyone

would want to hunt possums; they’re not crafty prey and, although

some people eat them, they’re not considered particularly delectable.

Those few introduced opossums thrived in California. Over the next

few decades, they spread up and down the coast, following humans and

coexisting with us on our farms and in our yards. Part of the reason

for their success is that they will eat nearly anything. They enjoy

lizards, mice, eggs, earthworms, fruits, berries, vegetables and even

road kill.

When dawn breaks, possums will hole up in a culvert, brush pile or

under your shrubbery or deck. At night, they climb trees and fences

and walk along the block walls that separate our yards.

Unless you’re trying to grow fruits and vegetables for your own

consumption, they don’t do much harm. They may even benefit your yard

by eating snails.

Once they’ve consumed everything in your neighborhood, they move

to another one. They rarely stay in one area for more than a couple

of weeks.

As you are probably aware, opossums are marsupials, which are

primitive mammals with pouches. The embryos develop for only about 13

days after the female has mated. Then the young are born in a very

primitive state.

The female licks a pathway in the fur on her abdomen so the young

can crawl into her pouch on their own. There they attach to a nipple

and continue to develop for another two months.

The female may give birth to up to 20 young, so tiny that all of

them could fit into a teaspoon. But the female has only 13 teats. Any

young that fail to find a nipple will die.

Thus the female can raise a maximum of 13 per litter. In fact,

fewer than that usually are born; most litters average seven to eight

baby possums.

At around two months, the young begin to explore the world. They

leave the pouch briefly and ride around on their mother’s back as she

goes about her business. At three months, they are weaned. Although a

newly weaned, 7-inch-long baby possum may look too tiny and frail to

be on its own, they’re fully independent at that size. But life in

the wild is rough. Most don’t make it to six months, and very few

survive past two years.

Despite their seemingly fragile nature, marsupials have been

around for about 145 million years. They evolved during the late

Jurassic or early Cretaceous periods in the age of dinosaurs.

In case you’re picturing landmasses that look like today’s map,

think again. During the Jurassic, the giant landmass of Pangaea began

to break up into two continents. Europe and Asia formed one

continent. Australia, Antarctica, Africa, South America and North

America were connected as the other continent.

Fossil evidence suggests that marsupials originated on land that

would become North America. They moved to South America, and then to

Australia.

The Cretaceous Period saw a further disconnection of landmasses as

Australia separated from South America. The marsupials in Australia

remained in splendid isolation. Until the arrival of early humans and

their dogs in Australia, marsupials such as kangaroos, koalas,

wombats, and sugar gliders were the only mammals found there. There

are still about 250 marsupial species in Australia.

About 60 species of marsupials are found in Central and South

America, along with a lot of placental mammals. There are no

surviving marsupials in Europe, Asia, Africa or Antarctica. The

Virginia opossum is the only marsupial remaining in North America.

We hear some folks in the southeast like to eat possum. They catch

one, fatten it on cornbread and buttermilk for a couple of weeks,

then kill it and remove the head, tail and entrails. They scald the

possum briefly in boiling water and pluck off the hair, then boil it

for 30 minutes. They place the parboiled possum in a roasting pan

with sliced raw sweet potatoes and bake it for one hour at 400

degrees.

But if possum really tasted good, there probably wouldn’t be any

of them left. We recommend that you leave the things alone and let

them go their way, as they have for millions of years.

* VIC LEIPZIG and LOU MURRAY are Huntington Beach residents and

environmentalists. They can be reached at vicleipzig@aol.com.