The Firefly Forest

Greater Earless Lizards (Cophosaurus texanus) are found in rocky desert and upland areas in Arizona, New Mexico, Texas, and Mexico. Here in the Sonoran Desert, these lizards are especially fond of sandy washes with large rocks. This male Greater Earless Lizard was perched on a rock in Tucson's Sabino Canyon on a sweltering August day. Sun-loving Greater Earless Lizards are active during the daytime, even on hot days, but you will often see them resting with a straight-legged stance to elevate themselves above the baking heat of the rocks.

Greater Earless Lizards are medium-sized and gray to tan in color above with cream, brown, peach, or orange spots, a dark banded tail that is boldly banded with black and white below, and two distinctive dark bands on their sides near their back legs. These dark side bands can be faint on the females, but they are a bold black on the males and edged with orange and turquoise, making the sexes easy to distinguish. Greater Earless Lizards get their common name from their lack of external ear openings.

When fleeing potential predators, a Greater Earless Lizard will often tail-wag and run with its tail curled over its back, revealing the bold black and white banding under the tail. The similar Zebra-tailed Lizard (Callisaurus draconoides) will also wag its black and white-banded tail when fleeing predators, but if you can manage more than just a fleeting glimpse of it, this lizard can easily be distinguished from a Greater Earless Lizard because its two dark side bands are just behind its front legs. Unlike the elusive and speedy Zebra-tailed Lizards, Greater Earless Lizards are easier to photograph because you can often find them perched quietly on rocks like this one.

House Wrens (Troglodytes aedon) are small, plain wrens found throughout most of the Americas in wooded thickets and in areas of dense, shrubby vegetation from southern Canada to the southern tip of South America. House Wrens are not only widespread, they are also quite common, and I have observed them in many places here in the United States and in Costa Rica. In June of 2008, we observed this House Wren below near the 9,157 foot (2791 m) summit of Mt. Lemmon in Arizona's Santa Catalina Mountains. Here in southeastern Arizona, House Wrens are common summer residents in mountain pine forests and fairly common winter residents in lowland brushy areas.

House Wrens favor low, dense cover, and with their small size and drab coloration, they would be difficult to spot if it were not for their constant activity and frequent dry chattering and scolding calls. We had apparently strayed too close to this one's nest, and the angry wren hopped from branch to branch in a nervous, agitated fashion and furiously scolded us. The House Wren's scolding diversion proved successful and we never did spot its well-hidden nest. Once we moved away, the relieved House Wren quieted down and disappeared into the bushes.

House Wrens are among the plainest of wrens due to their drab brown coloration and lack of distinct markings other than faint brown barring, a buff eye-ring, and an often indistinct light eye-line. This plainness distinguishes them from all other wrens here in the U.S. except for western Winter Wrens (Troglodytes troglodytes). However, Winter Wrens have only a short stub of a tail and are thus easy to distinguish from House Wrens.

As their common name indicates, House Wrens will nest in birdhouses, especially those designed for wrens. These eager little cavity nesters have even been known to puncture the eggs of other cavity nesting birds and usurp their nests. Despite this sometimes naughty behavior, House Wrens are quite beneficial to have around because they eat insect pests and will nest in disturbed, fragmented habitat like suburban backyards avoided by some other insectivorous birds.