Not Your Average Squirrel

It seems on any walk in the desert, I see a Harris’ Antelope Squirrel.  Usually the creature runs ahead of me, a tiny tattler scampering off to tell, there’s an intruder afoot!  Even in August, when heat lies heavy on the land, the Harris’ Antelope squirrel can be seen skittering toward the shelter of its burrow, tail over its back like a jaunty banner.

Of the three squirrels that live in Arizona, only the Harris’ stays out and about summer and winter.  She forages in the rocky lowlands, running in search of cholla and barrel cactus fruits, seeds, mesquite beans and insects.  Wolfberries and ocotillo flowers add variety to her diet. 

Millions of seeds lie buried in the desert soil, waiting for rain.  The Harris’ Antelope Squirrel sniffs out these seeds and digs them up, leaving tell-tale depressions in the grit. She scrambles easily over the curving spines of the barrel cactus to feast on the fruits up top. 

A ground dweller, the Harris’ Antelope Squirrel digs holes under sheltering cacti and desert shrubs.  Several holes together along with mounds of loose dirt mark underground burrows used for shelter and nesting.   

One of few creatures active in the summer, the squirrel carries her own shade – a fluffy tail, which makes a nice umbrella.  In the hottest part of the day, overheated from foraging, the squirrel retreats to her burrow and sprawls in the relative cool to disperse body heat.  Then its back to work. 

The squirrels are hunted by every desert predator, from raptors to snakes to coyotes.  Although solitary creatures, they are known to rise up on hind legs when danger lurks, and give a shrill trilling call. 

Somehow the wicked spines are not a problem
This squirrel wanted my snack and had to be shooed away. Usually they are very shy.

Hares One For You

Large eyes scan for danger overhead and around

See how comfortably the Black-tailed Jackrabbit sits. This is a hare supremely adapted to desert life.  Enormous ears swivel, keyed for danger. He keeps a keen watch above for hunting owls and hawks. At the slightest breath of danger, the jackrabbit freezes, and his dun colors melt into the desert hues.  If a predator advances, the jackrabbit sprints away, speeding up to 35 miles an hour.  His elegant bounds carry him 15 feet in a single leap, he rockets right over boulders and shrubs.

Two species of jackrabbits, Black-tailed and Antelope, live in the Sonoran Desert.  These mostly nocturnal hares browse at night and rest in the shade of desert trees during summer’s searing heat.  Herbivores, they feed on grasses, forbs, mesquite leaves and beans, and cacti.  Cacti supply needed moisture.     

Despite constant danger from predators such as raptors, coyotes, bobcats, rattlesnakes, and human hunters, jackrabbits gather together to graze at night.  Especially on moonlit nights, up to 25 jacks congregate to feed, finding safety in numbers.  The animals may travel several miles to find forage.   I love the image of a drove of jackrabbits loping along together, leaping and browsing, among plants now crisp and brown, the moon’s shadows alive with mystery.

Courtship between a jack and jill is a vigorous affair. The couple chases, bounds and leaps over each other.  Just one or two babies (leverets) is born to a litter. As with all hares, the tiny newborns are fully furred, with eyes open, and are soon able to run with their parents.  Youngsters stay on with their mothers for several months before becoming independent.  Jackrabbits breed throughout the year.

Oversized ears regulate and reduce body temperature

Spectacular Southwestern Speckled Rattlesnake

Speckled Rattlesnakes coloring matches the rocks in their habitat

A morning in June, hiking in a rocky canyon, my wandering thoughts were broken by an insistent buzz. It sounded like seeds shaken in a gourd. The circular edges of the coiled snake caught my eye. So hidden, yet in plain sight. If she hadn’t warned me, I would have stepped within a foot of where she lay cozied up to a granite boulder.

Yet this rattlesnake had already sized me up, literally.  Pit vipers have heat sensing pits located behind each nostril. These allow rattlesnakes to detect differences in temperature from several yards away.  As I approached, the snake perceived my outline and would be able to do so even in pitch dark.  During the day, keen vision contributes to the picture the snake considers to decide if an animal is potential prey.  I am a bit big for even this large snake to swallow whole, so mostly she was just telling me to back off. 

Pinned by the glare of the rattlesnake, I reached slowly for my camera. She rattled some more. I was plenty far away, but it’s not often we encounter critters that have the ability to do us serious harm. A combination of fear and awe put a shake in my hands. But her rattle shakes like you can’t imagine, vibrating up to 60 times per second, causing the segments of keratin at the end of her tail to buzz.

The venom that so scares us hikers is an amazingly complex combination of proteins, including neurotoxins, anticoagulents and hemotoxins. Every species of rattlesnake injects a slightly different venom that helps immobilize their prey and begins the digestion process.  

These remarkable creatures do great work in the environment, keeping a cap on surging populations of rodents, squirrels and rabbits.  Beautifully camouflaged to blend into their habitat, rattlesnakes are graced with incredible adaptations that allow them to hunt even without limbs.  In a few more months the snakes will be underground in hibernation and then I’ll go back to the rocky canyon.

Western Diamondback crosses trail at McDowell Mountain Regional Park
Rattlesnakes add segments to their rattles with every shed – 1 to 4 times per year

Peeking In

Note the spines of the cactus sheared off near the nest

I saw the nest from the trail and wandered over to have a closer look.  It was tucked up inside a wickedly prickly Jumping Cholla.  The nest was only a couple of feet off the ground and when I peeked in I was surprised to see three lovely turquoise eggs, spotted with brown.  Curved-bill Thrasher eggs.  I took one picture and hurried away.  Surely a parent was nearby.

I photographed a Curved-bill Thrasher carrying a twig back in the middle of March.  This pair must be starting a second brood.  Couples mate for life.  When nest building, they work together on an outer nest of thorny twigs. Then the female shapes the soft grass lining.  Both parents work to keep the nestlings fed, and even after they leave the nest, the youngsters will rely on mom and dad. The parents continue to feed their young and teach them to find food for several more weeks. 

Curved-bill Thrashers forage on the ground, probing with their beaks among plant litter and in the soil for insects and seeds.  They also eat cactus fruits, seeds and nectar.

The two note whit whee call of this common bird is familiar to desert dwellers.  Thrashers are songbirds, relatives of mockingbirds.  Their song is a soaring, crystal clear serenade, often sung at daybreak and dusk.

A thorny protective nest site
Curved-billed thrashers obtain moisture from juicy saguaro fruits and flowers
It all starts with a single twig

Warrior Bird

Greater Roadrunner is a member of the cuckoo family

No wonder it fell to Roadrunner to face off with Wylie Coyote.  Comic, daring and yes, even brutal, the Greater Roadrunner is not your average bird.  Slender and dramatic he is all speed and flash, as he cocks his long tail and ruffs his shaggy crest of head feathers.  In great bursts of speed (15 mph!) he runs down his prey of lizards, insects and snakes.  Even rodents and small rabbits may fall to a swift blow to the neck from the long powerful beak of Roadrunner.  Reptiles are more like to be beaten to death, but all prey is bashed repeatedly on the hard ground to break up bones for easier swallowing.  Roadrunner will even take on a rattlesnake.  The bird mesmerizes the rattlesnake with the tips of its wings, casting them about to confuse the snake. Two Roadrunners will also work together to bring down a rattler.   

Roadrunners build nest platforms in cactus and lower tree branches.   The good-sized nests are built with thorny sticks and lined with leaves, grass, feathers and sometimes snakeskin. Three to six eggs are laid and both parents care for the young.  If food is scarce the most vulnerable chicks may become food for the rest.

See the hidden bird? Is it a Roadrunner?

Quirky Quails

What’s more charming than a Gambel’s Quail? The male’s ringing call and the constant back and forth clucking of the family group is fabric of the desert.  A somewhat comic and vulnerable image is belied by the bird’s regal attitude.  

A quail family with twelve fledglings has been visiting our back yard to drink from a shallow saucer and to graze in the lawn. Quails eat greens, cacti fruit, seeds and insects.  We watched the parents lead the baby quails to the water source (covered so they can’t fall in) and shepherd them around the lawn. The tiny chicks have one speed, a dead run.  They nibbled grass and nabbed insects.  Dad perched nearby, alert to danger. Occasionally mom ran at one of the chicks, and smothered it to the ground under her breast for a moment before allowing it to run again. 

A female quail lays one egg a day over a period of 10 to 12 days.  Only then does she begin to incubate her nest.  This allows all of the eggs hatch on the same day.  The family is immediately on the move.  The precocial young are born covered with down and are able to run within minutes of hatching.  It will be 10 days before they can fly enough to reach greater safety.

Gambel’s Quail practice population control.  The birds only breed in wet winter years when there will be ample food for the parents and the chicks.

Three of twelve chicks in our yard
Clear photos of these fast moving targets is not easy

Colorful Kingbird of May

This elegant bird began hanging around the backyard in the middle of May.  She surveyed the area from our agave stalk, drank at the fountain, and perched in the Palo Verde tree out back.  Never having noticed this bird before I had to check my field guides. We had a Western Kingbird!

An acrobatic flier, the Western Kingbird flies out from her perch, grabs one winged insect in her beak, tracks down another and snags it too, and then ferries the entire snack back to her perch where she beats and shakes the meal into submission before swallowing.  She can also hover near a shrub and glean insects from the leaves and branches.

Western Kingbird is part of the tyrant flycatcher family, so called because of her aggressive defense of her nesting territory.  She makes no bones about scolding and chasing any intruder, even the much larger red-tailed hawk or the much more lethal American Kestrel.

Western Kingbird likes a habitat with tall perches and open areas where she can hunt.  We must have had a nice hatch of tasty tidbits that attracted her to our yard.  Or maybe it was the water.  Maybe the two together made our yard a stop-over on her way north.  She only stayed around for about a week.

Found across the western states and into southern Canada, the Western Kingbird migrates south to Mexico at the end of summer, stays there for a molt, then flies the remainder of the way to Central America for winter.  There is a small population that just goes to Florida for winter. 

Leguminous Trees

Ironwood Pods rich in protein, calcium and iron

Most desert trees are legumes, meaning they produce pods.  (Beans and peas are also legumes.)  Masses of spring blooms gradually give way to lengthening seed pods that ripen at the height of summer.  This is just when most species are scrambling to feed families of babies. 

The crunchy fare provides sustenance for desert critters including coyotes, javelinas, Harris’s antelope squirrels, pocket mice, kangaroo rats and rock squirrels.  Some of these animals are destined to become prey for meat eaters like owls, hawks, coyotes and desert snakes.  Through this dynamic cycle, ironwood, mesquite, and Palo Verde trees set the table for wildlife.

Desert legumes also have an almost magical ability to feed the desert underground.  Desert soils are notoriously lacking in nutrients due to aridity and lack of organic matter. Legumes coexist with soil bacteria that provide surplus nitrogen to their root systems. High levels of nitrogen are essential to the development of protein, making the legume pods very high in protein.  Nitrogen helps nearby shrubs and annuals grow, which provides more forage for animals like lizards, desert tortoises and cottontail rabbits.

As a bonus, trees also create microclimates of shade where tender sprouts such as saguaro cacti grow.  Animals like jackrabbits and javelinas wait out the midday heat under the protective drape of ironwood branches.  Crawling on the branches and among the bark, a variety of insect species feed on nectars, saps and the bark itself.  As they flourish, these insects become a protein rich and often juicy addition to adult and baby bird diets. 

Mesquite beans
Palo Verde pods
Palo Verde pod factory