predators

The Coachwhip – a colorful snake

The Coachwhip (Masticophis flagellum) is a fast, colorful, non-venomous, but sometimes aggressive snake that can get up to eight feet long, but most are three to five feet long. Coachwhips come in a variety of colors including tan, gray, pink, black, reddish-brown, or any combination of these colors. Broad cross bars are common. The red coachwhip is most widespread in the Sonoran Desert. A black phase occurs in Tucson and the Tucson Mountains. I saw a coachwhip in my backyard recently; its front third was black; the rest red.

Coachwhip1

These snakes range throughout the southwestern United States south through Baja California and Mexico (except the Sierra Madre) and inhabit deserts, prairies, grasslands, woodlands, thornscrub, and even cultivated lands.

According to the Arizona-Sonora Desert Museum (ASDM):

“Active during the morning and late afternoon, the coachwhip is often seen crossing roads. A speedy snake, it has been clocked at 3.6 miles per hour. The coachwhip is a nervous snake and may retreat into rocks or rodent burrows when threatened, but it is just as likely to approach an intruder hissing, striking, and possibly shaking its tail; it will bite if handled. During summer, four to twenty eggs are laid, hatching 44 to 88 days later. Young and adults feed on mammals, birds, bird and reptile eggs, lizards, snakes, carrion, and insects; the prey is seized and swallowed without being killed.”

I’ve often seen coachwhips in the aviary at ASDM where they hide in trees and prey upon birds.

There are some myths about this, and similar, snakes. According to Wikipedia:

“The primary myth concerning coachwhips, that they chase people, likely arises from the snake and the person both being frightened, and both just happening to be going the same way to escape. Coachwhips are fast snakes, often moving faster than a human, and thus give an impression of aggression should they move toward the person. The legend of the hoop snake may refer to the coachwhip snakes.”

“Another myth of the rural southeastern United States is of a snake that, when disturbed, would chase a person down, wrap him up in its coils, whip him to death with its tail, and then make sure he is dead by sticking its tail up the victim’s nose to see if he is still breathing. In actuality, coachwhips are neither constrictors (snakes that dispatch their prey by suffocating with their coils) nor strong enough to overpower a person. Also, they do not whip with their tails, even though their tails are long and look very much like a whips.”

See the Article Index page for more stories of the Sonoran Desert.

A green lynx spider may be lurking in your yard

Spring flowers bring out the pollinators and their predators. I found one of those predators, a green lynx spider, lurking in the flower of a prickly pear cactus. Can you see the spider in the middle of the flower in the photo below?

Green-Lynx-Spider

 Rather than build a web to catch prey as some other spiders do, the green lynx spider lurks on foliage to catch prey. It pounces cat-like, hence its name “lynx.” Its color helps camouflage the spider. This is a fairly large spider; the body of a female can be nearly an inch long. The legs sport spiky hairs. This spider is big enough to tackle bees and butterflies.

As with most spiders, the green lynx spider paralyzes its prey with venom which also starts the digestion process. Spiders don’t have teeth, so the venom serves to liquify the prey so that the spider can suck up the juices.

In September and October, the female spider will build a silk sac and lay up to 600 eggs. She guards that sac and new hatchlings ferociously until after their first molt.

The green lynx spider is generally harmless to humans. So, if you have flowering prickly pear cactus in your yard, go out a take a close look in the flowers and on the pads. Maybe you will see a lurking “lynx.”

See more photos of the green lynx spider at the Arizona-Sonora Desert Museum digital library here.

 

Western Screech Owl, a feisty little raptor

The Western Screech Owl (Otus kennicotti) breeds throughout the western U.S., from southern Canada to Baja California, and other parts of Mexico. This little owl is the fourth and smallest of the raptors I handle and interpret at the Arizona-Sonora Desert Museum. I’ve written previously about the Harris’ Hawk, the Barn Owl, and the American Kestrel. (I also handle snakes.)

Western screech owl

The Western Screech Owl has a body length of 8- to 10 inches, and a wingspan of 20- to 24 inches. (The infamous Cactus Ferruginous Pygmy Owl is slightly smaller.) The yellow eyes are very penetrating. When alert or excited, it raises some feathers on its head – “ear” tufts. The owl is usually gray and streaked with black and white (there is a red race). The only other owl in this region it may be confused with is the Elf Owl, which is much smaller (5 inches in length) and lacks the ear tufts. The screech owl’s toes are zygodactylous (two pointed forward, two pointing backwards). There’s a word for Scrabble fans.

Screech owls generally do not migrate. They are cavity nesters, so you might see one peeking out of a hole in a saguaro cactus. (They will also nest in boxes.) The female lays 4- to 6 eggs, each about 2- to 3 days apart. The chicks hatch after about 26 days and open their eyes after about a week. The female broods the chicks for two weeks while the male brings food. The chicks stay in the nest for about five weeks, all the time being fed by their parents. Life expectancy in the wild is 4- to 6 years, but captive birds are known to have reached an age of 18 years.

The Screech owl is a fierce predator and will attack prey much larger, relative to its size, in comparison with other owls. The screech owl will attack large Norway rats, mice, lizards, insects, smaller birds, scorpions, spiders, ground squirrels, and fish. Its normal habitat in the desert is the wooded areas near mountains, or along tree-lined rivers. In wooded areas, the owl’s dull color makes good camouflage.

Despite its name, the owl doesn’t screech. Instead, it has a series of trilling calls. Screech owls have keen hearing which help in capturing prey, but their hearing is not as specialized as that of the Barn Owl.