Few places in the United States can rival the watershed of Arizona’s San Pedro River as one of the nation’s premier birding hotspots. A phenomenal richness of birds has been documented here – well over 450 species. Join me as I celebrate this gift of life with a sampling of our beautiful, diverse, and fascinating avian fauna…
One of the rarest colors among all the creatures of planet Earth is blue, here brought to brilliant life by a male blue Grosbeak, (Passerina caerulea).
The broad-billed hummingbird, (Cynanthus latirostris), tiny and utterly dazzling, underscores the need for a pair of good binoculars to enable full appreciation – not to mention a heightened sense of wonder – of this jewel-encrusted sprite. Unfortunately, it has been dubbed with one of the dullest and most unimaginative of names.
Hummingbirds are important pollinators of many native plants. Here, a fitting example of coevolution presents itself: the saguaro evolved to raise its flowers high into the desert air as an offering to flying pollinators like bats and hummingbirds. The bats and the birds are able to locate these tall beacons at long distances. The height of the saguaro’s blossoms ensures that its pollinators will remain secure and at ease, out of the reach of a long list of ground-based predators.
Ravens are the most intelligent birds in our country – they possess larger brains relative to their body size than any of our other species. Ravens also have the largest vocabulary of all American birds, they mate for life, and they can live for decades. These black-as-night birds are absolute masters of flight. Magic attends all ravens. This is Mavis, a female Chihuahuan Raven (Corvus cryptoleucus), who has successfully raised many broods here on our property with the help of her mate, Mike.
A fledgling raven spends months with its siblings and parents, exploring and learning about its world. During that crucially important period in their lives, the young birds meet many of their neighbors for the first time. Adult box turtles like this one have little to fear from the fledglings, but neonate turtles are a favorite food.
Cooper’s Hawks, (Accipiter cooperii), are what instill constant wariness and universal fear in most other birds of smaller or equal size. These hawks are specialized, highly skilled bird hunters. Utilizing the combination of a long, rudder-like tail, lightning reflexes, powerful flight musculature, and incredibly sharp eyesight, they are among the world’s most capable avian predators.
The sight of a Crested Caracara, (Caracara plancus) in the Middle San Pedro Valley is a rare treat. Caracaras are classified as members of the Falconidae, the falcon family. The crested caracara is the world’s second largest falcon.
Elegant, gorgeous, and highly social, Gambel’s Quail, (Callipepla gambelii) are common valley residents. The ecology of this species is closely linked with Gila monsters, for quail eggs (and occasionally young chicks) are a major food source for the big lizards. Greater Roadrunners, (Geococcyx californianus), are a frequent sight here, but seeing them in snow is anything but common, for snow is rare in the valley floor. Their tail feathers display are an eye-catching blend of beautiful iridescent greens and bronze. Roadrunner populations are locally cyclic, but what determines that is something I have yet to learn.
Lark Sparrows, (Chondestes grammacus), are a great example of why no one should be without a pair of binoculars. Seen with the naked eye, they are just another small, drab brown bird. Viewed through binoculars, these sparrows come to life with ornate patterning and rich, saturated colors.
A Loggerhead Shrike, (Lanius ludovicianus) scans for its prey from an elevated perch in a velvet mesquite. “Loggerhead” refers to the shrike’s unusually large head. (The largest non-pelagic turtle in our country also shares this moniker with the shrike: “loggerhead snapping turtle.”) Shrikes sometimes impale their prey on long thorns and even on barbed wire. This beautiful predator has been in sharp decline all across its range for decades. Loggerheads are the only shrike endemic to the United States. Dressed in vivd red hues, Northern Cardinals, (Cardinalis cardinalis) are a visual standout in any habitat type – that is why cardinals tend to spend much of their time concealed in dense shrubs or other types of thick cover. In the valley, cardinals have a very close association with graythorn (Zizyphus obtusiloba) bushes, where they find safety and peace of mind within the thick maze of very thorny branches that so characterize graythorns.
As humans, we tend to conceptualize and visualize birds either in flight, or as viewed laterally (from the side). I think this posterior view of a northern cardinal may outdo any other viewpoint – what an amazing crest!
Decades ago, Spotted Owls, (Strix occidentalis) ignited a huge controversy when they were added to the endangered species list. Many people lost sight of the fact that it was not just the birds that mattered, for spotted owls were a symbol for what really mattered most: the ecoregion itself – the magnificent coastal rainforests of our westernmost states that have literally been torn to shreds by humanity’s rapacious demand for wood products. Few people know that these owls are also residents of the Sierra Madrean Ecoregion. Sometimes known as “Mexican spotted owls,” this subspecies – Strix occidentalis lucida – reaches the northern tip of its range in the San Pedro Watershed. During a very lucky day, I photographed this individual in the Huachuca Mountains.
There are few more vivid ways to mark the coming of spring to the Middle San Pedro Valley than the arrival of Vermillion Flycatchers, (Pyrocephalus rubinus). These tiny birds light up the fields and bosques in early March – before the mesquite trees leaf out. Adult males are wearing freshly grown feathers in March, plumage so pure and bright that these minuscule flycatchers can be seen with the naked eye at distances approaching 100 yards. Their crowns sport the most radiant part of their plumage, hence the name “Pyrocephalus,” which translates to “flaming head.”
First, an important message to my readers: For a much better experience, when you receive notice of new blog posts in your email, please be sure to click on the blog’s title. That will take you to my blog website, where the photographs are larger and the text is more readable. Also, there is a “featured image” at the top of every new blog post that does not appear in the email version. Do this now – you will notice a substantial improvement!
Summer has come to the river and its valleys, bringing a cavalcade of change to the animal world. Today, my thermometer registered 113° F. I don’t leave southern Arizona during the summer like so many people do every year. This is my favorite season here, because so much happens in the natural world during the fierce heat of summer…
Mike and Mavis have successfully raised their seventh brood here on our land. This year, four new ravens have fledged and left the nest. Here are two of them. Note the pinkish-white bordering around their beaks and their pink mouths. As they mature, the pinkish color on their beaks disappears, and the inside of their mouths turns black.Several weeks ago, the velvet mesquite trees erupted with fresh blossoms. These are the precursors to an abundance of bean pods that provide one of the most crucially important food sources for the valley’s wildlife.A closer look at the flowers of a velvet mesquite tree. These blossoms perfume the air with a sweet, heady fragrance.A queen butterfly alights to drink from the wet mud surrounding our watering hole. This insect is often mistaken for its well-known cousin, the monarch.The back side of a male Gould’s turkey in full display. These birds – and their tails – are huge! The white tips on the tail feathers are one of the field marks that distinguish this race of wild turkeys from their eastern relatives. Part of the display involves dragging the wing tips on the ground, an action that creates a loud rasping sound, meant to intimidate rival males.A male summer tanager comes to feed from a block of suet. This is America’s only all-red bird, a living statement of resplendent color and grace. Their future in this valley is being threatened by large numbers of brown-headed cowbirds.This male black-headed grosbeak has been sending his voice through the bosque every morning, a series of loud, robin-like notes.Few of our western birds are more strikingly colored than the western tanager. A different race of this species stays here in the valley floor to breed every summer. Most western tanagers utilize very different breeding habitats – namely, conifer forests at higher elevations.A male blue grosbeak that visits daily for water. Blue is one of the rarest of colors among Earth’s terrestrial vertebrate animals.A new beaver dam graces the flow of the San Pedro River. Dams like this permit substantially more water to infiltrate the ground below their surfaces, recharging the shallow aquifers that give life to the river’s riparian forests of cottonwoods and willow trees. There were five more dams below this one. I cannot think of a single mammalian species that is more beneficial to the river and its forests than beavers are.I awoke one morning to find this characteristic fresh imprint at the foot of my entry steps. A rattlesnake had curled up there the night prior, leaving its signature circular mark. No other Arizona snakes rest in such a circular position. For reference, the grizzly track cast in concrete is six inches in width. Grizzlies were once common along this river until they were wiped out by Spanish and American settlers.A black-tailed jackrabbit resting in the shade of a mesquite trunk on a toasty summer day. When the heat cranks up, animal behavior changes. This hare let me approach within four feet, something it would not have allowed on a cooler day. The name “jackrabbit” is a misnomer, as these creatures are hares, not rabbits. Until I came to live in southeastern Arizona, I would not have believed that there could be pink snakes native to our country. This coachwhip snake appeared on a hot afternoon, five feet of blazing bubblegum pinkness! Coachwhip snakes are expert climbers. Kathleen and I looked out a window one day to see this tail protruding from an active Gila woodpecker nest. Fortunately, the snake did not wipe out the entire brood – it consumed one or two nestlings and moved on. A gopher snake encountered on a sandy bank of the San Pedro River. These snakes attain lengths of seven feet or more and are often mistaken for rattlesnakes. They are among the most effective rodent controllers we have. Favored food items include mice, rats, and gophers.A diamondback rattlesnake slithers through the mesquite bosque, traveling in a manner common among rattlesnakes, using caterpillar motion. When snakes crawl in this fashion, their bodies remain almost straight rather than sinuously curved. We never kill these animals. They have a right to live here, no less than we do. When summer comes, we are always on guard, watching closely where we place every footstep, especially after dark.Beavers add a special touch of beauty to the river, creating ponds that mirror their surroundings and provide needed habitat for a long list of other creatures.
