The Cactus Wren - Arizona's State Bird

Sentry of Choice
      One insatiably curious bird of the southwest desert can be a surefire venomous snake detector. Gardeners and hikers can detect rattlesnakes easier if you listen for the signal.

Listen to Cactus Wrens 
     I've been around cactus wrens all my life yet had never given them a second thought.  Sure, they're the largest member of the wren family, live throughout the Southwestern desert and are the official Arizona state bird. But they're also pesky, loud, and you have to keep the windows rolled up on your car or they end up inside, spotting the upholstery.

     Over the past years, however, I’ve learned to regard the cactus wren (Campylorhynchus brunneicapillus) as extremely important. These insatiably curious birds of the southwest desert are also expert snake detectors and alarms. I now welcome them enthusiastically to my garden.

Cactus Wrens and Rattlesnakes

     Since cactus wren nests are only three to six feet from the ground, snakes and other reptiles find their eggs and nestlings easy prey. The birds are constantly on the lookout for one particular snake, the western diamondback or “coontail” rattlesnake. Folks who live in the desert sometimes familiarly call this snake Mr. Buzztail. It can be hard to see, as its colors blend perfectly with the desert floor.

     The cactus wren’s keen eyes for predators, specifically rattlesnakes, can be of great importance to humans. Using one primary form of communication, this wren can warn hikers, horseback trail riders, gardeners, bird watchers, naturalists, hunters, outdoor enthusiasts and homeowners of possible impending danger.

     Rattlesnakes like to sleep in abandoned ground squirrel holes. Often these holes are directly under a cactus wren nest. From the moment the snake pokes its head out for a breath of fresh air to begin its daily hunting ritual, the wren family is alert and wary.

     To say I highly respect rattlesnakes is an understatement. Growing up in rural Arizona, I’ve watched them sleep, hunt, kill, fight and even bear their young live. I’ve poked them with a stick, sprayed them with water, and killed them with my gardening shovel, trying in vain to discourage their presence. But most importantly, I’ve learned that I always want to see a rattlesnake before it sees me!

     With a determined, loud, repetitive voice an alert cactus wren sounds the alarm, "Snake!" the bird sentry jabbers repeatedly and ceaselessly. The squawking and loud racket continues as family members join in the chorus. It’s important to note that I have also observed sparrows, bluebirds, thrashers, mockingbirds, jays and other species band together with the wren family to warn of the snake’s presence. As many as 20 birds may gather in a cactus or tree - tattlers on the rattler.  
     I regard this avian audience with high honor. When I hear their distress call I stop what I am doing and cautiously walk in the direction of the scolding calls. I walk very slowly as I get closer to the birds. There are those who prefer a shovel or shotgun, but now I grab my snake stick with a noose on the end. The wrens are relentless, calling and almost pointing to the trespasser. I transport Mr. Buzztail to less inhabited area, away from children, pets, and livestock. And yes, I know also that rattlesnakes have a established territory of about one mile.and relocating them farther away is risky. I usually taken them to an area I know has dens and other rattlers of the same species, then wave goodbye and wish them luck surviving with new competition and environment.

     Many times the birds find a harmless variety of snake, large lizard, or even a raptor in a tree. I just watch with delight as the kamikaze pilots dive at their enemy. I have seen a few brave wrens cautiously peck at the intruding snake’s tail, chasing as it slithers from the contemptuous chorus. I have observed this behavior in many species, but the cactus wren is my sentry of choice. The zealous attitude and undaunted courage are certainly worth watching or recording.

     Once the predator is removed, everything again settles back to normal. Birds return to their daily preening and feeding chores. I return to my gardening or continue my hike. Snakes continue to look for prey in new hunting grounds. And the cactus wren? He’s probably picking bugs from my car windshield or pulling nesting bits from the upholstery.

Cactus Wren Description and Habits

     Cactus wrens flourish where other species cannot. They are somewhat drab in color and extremely well camouflaged. Larger than most wrens, at about 8 1/2 “, they are comparable in size to their look-alike, the sage thrasher. The crown on its head is rust colored. The breast and under parts are shades of white and buff, with black spots – giving it a somewhat dirty look. The unmistakable white-striped eyebrow gives these wrens a cunning look. For the most part, their wings show broken white barring in gray and brown, with the tail striping more pronounced.

     Each cactus wren builds many flask or football shaped nests fairly close to the ground. They usually choose staghorn cholla cactus for their nest site, but may use well-protected Palo Verde trees. The nest contains a passageway leading into a safe haven among the protective thorns.

     Cactus wrens usually build many nests within their family territory. On main nest is used for brooding young birds, with sleeping nests located nearby. The nests are built of branches and twigs and usually lined with soft feathers, fur, cotton, and grasses. If you leave a torn jacket, quilt, or yarn outside, the cactus wren will find it and use the materials for the inner layer of the egg refuge.

     The female cactus wren lays two to five buff or salmon-colored eggs and can raise four or five broods per year. The eggs incubate for 16 days. The monogamous parents share the tasks of incubation and feeding of young. Once fledged, young cactus wrens will occupy nearby sleeping nests in the parents’ territory. They will also help feed and protect new nestlings, maintaining a strong family bond.

     This wren has a fairly wide range, inhabiting parts of Arizona, California, Nevada, New Mexico, Utah, Texas and Mexico. It prefers to live among the sharp spines of cactus and desert trees, and it’s always welcome in my yard.

(originally published in Bird Watcher Digest, Sept/Oct 1992)