Essays

Wild On The Prairie: Birds

The Inspector, the Cactus Wren
July 1, 2001

I love Cactus Wrens! "Good morning, Madame Inspector!" I cry out as soon as I see the first wren of the morning. "Oh, yes, we did prune that Phlomis last night," we tell the birds in an everyday way. The Cactus Wrens check out anything and everything that we do as we putter about the yard. We have found Cactus Wren feathers stuck to the flypaper that hangs above the pop-can recycling bin ten minutes after installing it. A workman at the Gone Native Arboretum once took off his long-sleeved work shirt, and within fifteen minutes noticed one of the sleeves straightening itself out. With every hop of the bird inside, the shirt jerked up. And with every jerk, the wren "growled."

The noise they make is really more than a growl -- it is a clattering roll: quick beats without melody. Somehow, the sound carries farther than other sounds and has a hollow echo that reverberates in the heat of a summer afternoon. A confidence and boldness ring loudly in their clattering song. They seem more purposeful than other birds. Intensity is obvious in their body language, and their actions are hyper-focused without hesitancy. Humans cannot distinguish between Cactus Wren genders by sight. Nor can Cactus Wrens. Males threaten every other male they meet, spreading the wings and tail as they growl. A female signifies her sex in such a meeting by crouching after spreading her feathers.

Territories are set by January -- female owners chasing away visiting females, male owners chasing away visiting males. Females fight female intruders, the first glancing blow of a swoop-collision resembling the battles of mockingbird versus cat, followed by a slap with a wing, and finally, if need be, a peck with the sharp beak. Males rarely fight, since song precludes such macho behavior.

The males sing at different stations along their boundary lines. Each station is twenty or so feet from the previous. First, they sing at one station, then go to the next, then double back to sing again at the first station. It is rare that appropriate habitat is so plentiful that a male has to patrol all four sides of his territory. An individual’s territory encompasses 10 acres on average. If a neighboring male advances, the resident male charges and fans its feathers. This threat usually suffices to end the incursion. The invader then exhibits displacement behaviour, picking up dead grass and dropping it, or chasing the nearest smaller bird.

If Cactus Wrens are hanging around, Curve-billed Thrashers are too. The bigger sickle-beaks love to tear up wren nests. Cactus Wrens build three to five nests per individual. A pair often has ten nests within their territory. Triple clutching can occur within one mating season, producing ten to eleven babies. One nest is used as the breeding nest, but how the other nests are utilized has never been adequately studied.

Cactus Wrens spend their nights in individual roost nests, and rarely use the same nest for more than a week at a time. According to modern ethological theory, every animal’s behavior is meant to benefit the preservation of genetic material. Cactus Wrens are just a little bit more complex and do not meet commonly held perceptions about bird behavior. Maybe the Curve-billed Thrashers just think that wren nests are trashy-looking, and that wrens breed too often. Humans display such prejudice, why not birds?

Sibling Cactus Wrens stay together for several weeks after leaving the nest. A constant quiet chatter connects the group as each object in the territory is inspected. Every plane of a six-by-six-by-six-foot prickly pear can be examined thoroughly by such a team. Like teenage humans, each seems to keep up a running commentary that broadcasts to the world the workings of their brains. "Nope, nope, no bugs here, nope, nope, oooh, ouch, daddgum thorn! Aaaah shade! Oh I thought I saw something! Hey brother! That was mine! Nope, nope, no bugs. This is all mine. Ooooh, what a good leaf-footed beetle, and here is some juicy rot full of fruit fly maggots! Away, this is mine, go away!"

At the Sibley Nature Center on hot summer afternoons, sibling trios have several times napped the afternoon away on the windowsills. At first three little birds will line up to examine not only their surroundings, but also their reflections. Slowly their eyes close. After a few minutes their little heads begin to lean forward, ever so slowly. Often they jerk themselves awake for a quick look around and then doze off again. Eventually their sleep deepens, and their heads lean forward until all are propped up by their beaks. In summer's mid-afternoon, plants wilt, birds nap, toads brumate, box turtles aestivate, but what do humans do? Yeah, just keep on working! Long live the siesta!

Sometimes juveniles from a pair’s first brood allow second-brood juveniles into their roost nests at night. Both of the first two sets of young have been observed helping to feed a third set. Due to such cooperative behavior, clutch success in Cactus Wrens is often as high as sixty-six percent -- well above the avian average. Before fledging, a baby has only snakes to fear. Roadrunners seem to be a major predator on the fledglings, but after surviving that the wrens consistently live their allotted four years. Their alert and curious ways protect them well.

The song of a Cactus Wren is an integral part of the Llano Estacado lifescape. To me, it is like the smell of crushed holy sage, or the whiff of gobernadora on the wind before a rain, or the bite of jalapeno just right in pico-de-gallo. It is part of what defines life as a Llanero. To some people the song of the Cactus Wren is harsh and rough, definitely non-musical, but why should the ethereal notes of a European Nightingale represent the pinnacle of bird song? Humans make themselves miserable despising what they have and wishing for different. Love comes from active participation. I love Cactus Wrens for all of their personality and communicative expressiveness. They are rock-and-roll, and Nightingales are Muzak.