Friday, April 24, 2009

Awesome Opossum

Wednesday afternoon I went outside for a walk and saw a critter waddling across the field. An opossum! Opossums are normally nocturnal, so I was glad it was out and about during the day so I could get some pictures.

I approached it cautiously, because I didn't want to scare it. Opossums go into a sort of coma when severely frightened. This is where the phrase "playing 'possum" comes from. It is almost as if it were dead. You can shake it and it still will not respond. The heart beat slows down, the breathing is slight and the body temperature lowers. This defense mechanism works because some predators do not prefer to eat what they have not killed. Eventually, the opossum will come out of it and go on its way. So scaring the opossum would mean I would not get any good pics. :(

Anyway, we had a stare down. It apparently thought I wanted it for vittles, so it went under a neighboring conifer for more protection.

I was hoping the opossum would "grin" at me and show its toothy smile, another defense mechanism. The gaped mouth and hiss even makes most humans back up.

Photo from Wikipedia
Even though the opossum has 50 teeth, more than any other land mammal, they rarely bite in defense. The skull shows the impressive teeth that are used mostly for eating. Opossums are omnivores and opportunists eating about anything they can find. They have an important job in the wild because they help keep down the rodent population by frequently eating rats and mice.

Opossums have an almost hairless prehensile tails that they use to hold on to branches as they climb. Something nipped the end off of this one's tail! Their feet are equipped with long toenails for climbing and with back feet that have thumbs for grasping branches. The long white guard hairs are also evident in this picture. This top layer of coarse fur helps keep the elements and dirt away from the softer, warm fur underneath. It works in the same way an overcoat does for us.

They have a large nose for discovering food. You can see a small drip coming from the mouth. The opossum is salivating, another defense mechanism. This is to fool me into thinking it is sick and therefore not worth the risk of eating. The opossum has long whiskers, as well, to help find its way around tight spaces in the dark. Each whisker has sensory nerves at the base so when the whisker brushes against something, the opossum knows how much room it has to squeeze through.

Photo from Opossum Society of the United States

The most amazing thing about opossums is the reproductive cycle. A baby opossum is born 11-13 days after conception! How is this possible? Opossums are the only North American marsupial, distantly related to kangaroos. Their young are born very small, then they finish developing within their mother's pouch. Above is a picture of a newborn. They weigh about .13 grams at birth. (A penny weighs about 2.5-3 grams depending on the year it was produced.) They must crawl up their mothers belly and go into her pouch to locate a teat. The mother will assist with this by licking a path for the young to follow. There they will remain attached to the teat for about 2 months. Around two and a half months, the baby opossums' eyes will open and they will soon outgrow the pouch. They will then ride around on the mothers back, learning where to find food and defense stategies. At five months they are on their own.

My friend, Dawn, is a rehabber and I had the pleasure of raising four baby opossums one year. Boy, they are ravenous little guys! They lived in my back bathroom for a few months. Occasionally they would make a break for it and take off for the living room to camp under the furniture. My cats would always tell me where they were. Cautiously approaching them and yowling about the whole experience. Pretty funny! I wish I had it on video.

Do you like animals? Check out more at the Camera Critters site.


Thursday, April 16, 2009

A Spring Walk

Over the last few weeks I have been checking out the forest for signs of spring. The wildflowers are amazing! Each day I have been looking forward to seeing what will be in bloom.

Bloodroot is almost all bloomed out. It is such a delicate flower that a hard rainstorm can knock off all the petals.

Spring Beauties are such cute little flowers. The light pink stripes are nectar guides that help the pollinators locate the good stuff.

An early butterfly, Eastern Comma. The "comma" mark that gives it its name is on the underside of the wing.

Dutchman's breeches look like old time pantaloons lined up on a clothesline.

Scarlet Elf Cup, Sarcoscypha coccinea, with its brilliant red center. This fungus grows on decaying wood. Below is a pic of how it is attached to the branch.

Scarlet Elf Cup side view.

Wild Ginger with its interesting dark red flower. This flower is found near the ground so it can be pollinated by beetles and slugs.

Citronella Ants, most likely in the genus Lasius, emit a lemon/citronella like smell when disturbed.
Here is a closer look at the citrus-scented critters. They are pretty common and I often find them under logs or rocks at the park. Citronella Ants farm honeydew, a sweet liquid produced from aphids and subterranean insects. Many species of ants will "milk" the aphids and other insects by gently stroking them with their antennae until they produce the sweet liquid. The liquid comes from the insects feeding on the phloem of plants where the sweet sap is located.

Enjoy the wonderful spring weather this weekend and check out Indianapolis nature!