Friday, September 11, 2009

Alligator Lizards

Three weeks ago I had hip replacement surgery. It has required me to take it easy, to allow healing to take place, to limit my activities. And in general, in this time of beautiful Indian summer, it has been a real pain. And boring, too.

So when Glen stumbled upon this Northern Alligator lizard sunning herself on the back porch, I was wildly enthusiastic. Well, I probably would have been pretty enthused anyway: I love all the "herps" ( lizards, amphibians, frogs, snakes, turtles). Twenty years ago I was a volunteer zookeeper assistant at Point Defiance zoo, and worked in the building that housed these animals. I got to see and work with some amazing snakes, tortoises, geckos, etc. These are animals that truly are from another planet.

But my fondness for herps was planted even earlier. In 1955 my parents moved to the outskirts of Olympia, near what is now Olympia High School. From our place looking east, all you could see was abandoned cow pasture and a few cow-chewed Douglas firs. This was the playground for me, my six siblings and all the neighborhood kids.
We saw Pacific chorus frogs in our apple trees, and chased after garter snakes. Nearby Hazard lake had salamanders and bullfrogs. All in all, it was a wonderful haven for herps and children alike.

One time we caught a huge bullfrog roughly the size of a dinner plate. I took it into the house to show my mom, and was surprised to see my normally unflappable mother become unglued when the bullfrog jumped out of the shoebox onto my arm. My surprise turned to a calculated glee as I stalked closer to her, menacing her with the bullfrog, despite her freaked out attempts to assert parental authority and get me to back off. It remains one of my better memories.

Anyway, back to alligator lizards.

Lizards are cold-blooded animals, so they especially like heat and sun, both of which are generally in short supply in western Washington. What this means is that lizards are also in short supply here; only the Northern Alligator lizard is considered widespread and common. It likes damp Douglas fir and Hemlock forests with sunny edges, where it can sun itself, and also catch its insect prey. If you, like us, find a lizard in your back yard, chances are very very good that it is this lizard.

They are active in the day, but tend to be secretive, so it's not common to find them. As I talked with a couple of friends who had seen them, I was told that they like houses with high exposed foundations, especially if those foundations are sunny. These flat concrete surfaces act as a rock face against which the lizards can soak in sunshine, but also pick up the stored heat the in "rock". Since our house is built on a high foundation, this probably helps bring in lizards.

The other factor is Schneider creek. I have written about this creek and its proximity to our house in previous blogs. Schneider creek emerges into a deeply forested ravine about one block from our backyard. This may provide the wet woodlands that Alligator lizards like; I speculate that these lizards use the forest edges of Schneider ravine, and venture into connected sunny backyards.

This particular individual is a fat female. Females bear live young as late as early September, and it is possible she is pregnant. Or not; she has clearly had a prosperous summer, and laid down lots of fat stores, which will help sustain her as she goes into an underground den to hibernate in October, slowing her body metabolism down to get through the winter months. Come next March she will re-emerge from her den, eat voraciously and find a mate. And so the cycle begins again.

Janet


Resources:
• Washington Herp Atlas: www1.dnr.wa.gov/nhp/refdesk/herp/
• The Reptiles of British Columbi: www.bcreptiles.ca/lizards/alligator.htm
• Reptiles of Washington and Oregon; authors Storm, Leonard, et al
• Many thanks to Bill Leonard for answering my questions.

1 comment:

  1. Thats really quite interesting. But if it is June, you find a large- bellied alligator lizard, and you think that it is a female,could it be pregnant, or is it just fat?

    ReplyDelete