Caluromys derbianus

The Central American Woolly Opossum is without a doubt one of the cutest opossums in Drake Bay. They have a short nose, big ears and large, engaging eyes.

Their fur is gray with rusty red highlights and they have a long, naked, prehensile tail. The name of their genus, Caluromys, translates to "Beautiful Mouse" in Greek.

Woolly Opossum are the most arboreal opossums in Costa Rica and they move through the trees with great agility and grace. In the years of doing the Night Tour we have very seldom seen one on the ground.

They are nocturnal and spend the days sleeping in their daytime retreat. Although we sometimes see them on moonlit nights, they usually prefer only the darkest nights for foraging.

It was a Woolly Opossum that gave us a surprise one night as we returned home from a Night Tour. We were still building our house, and had an old, creaky, wobbly, wooden ladder that we used to get to our room on the second floor.

As we approached, we saw what we thought to be one of our cats resting on the ladder. Suddenly, I looked up and saw our two cats peering down over the edge of the second level at the very same animal resting on the ladder that we were looking at! We had walked right into a stare down between our two cats and a Central American Woolly Opossum....INSIDE OUR HOUSE!

 We entered our house as quietly as possible, concerned the situation could get crazy very quickly. Luckily, the opossum and the cats held their ground even as we approached them.

After snapping a few photographs, the first photo featured on this page is one of them, we managed to get the opossum to climb on a broom stick and carried him outside.

Unlike the Virginia Opossum, that ranges into North America, the Woolly Opossum does not play dead when threatened. They are reputed to attack and bite when cornered!

Fortunately for everyone involved, there was an all around peaceful outcome to the tense stand-off.

Central American Woolly Opossums inhabit lowland rainforests as well as those in higher elevations. Very little is known about their behavior in the wild.

Although no in-depth studies have been done on their diets, scientists think they are probably omnivores. We often encounter these animals drinking nectar from Balsa Tree flowers or feeding on Mangos, Malay Apples, Cashew Apples and the stringy fruit of the Cecropia Tree. They have also been documented eating large moths which they snatch right out of midair.

Like all other opossums, Woolly Opossums are marsupials. After mating, females are only pregnant for about two weeks. They give birth to three to six tiny "larvae". The larvae's first test, as soon as they are born, is to make their way into the mothers pouch and attach themselves to one of her mammary glands.

They will spend the next two and a half months in her pouch completing their development. The young opossums are probably weaned by the time they are four months old. Woolly Opossums may live up to six years in captivity, although probably less in the wild.

References:

Henderson, C.  2002  Field Guide to the Wildlife of Costa Rica  University of Texas Press

Janzen, D.  1983  Costa Rican Natural History  University of Chicago Press

Sitole, S. 1999. "Caluromys derbianus" (On-line), Animal Diversity. Accessed October 05, 2008 at  http://animaldiversity.ummz.umich.edu/site/accounts/information/Caluromys_derbianus.html

Wainwright, M.  2002  The Natural History of Costa Rican Mammals  Zona Tropical

Weldon Owen Pty Limited  1993  Encyclopedia of Animals  Barnes & Nobles Books