A Celebration of Life in the San Pedro Watershed – Native Mammals

Being  grateful for what we have is a wise way to live. With the advent of this new year, I feel an urge to share a gallery of original photographs that reflect that gratitude. It is a privilege to share habitat with the rich variety of living creatures that so grace this landscape. All of the following images, with only one exception, were taken within the watershed of the San Pedro River. All of the animals were wild and free  when photographed. Meet a few of the 90 species of mammals that live here…

This bobcat (Felis rufus) was sitting quietly near a gopher mound, hunting pocket gophers. Eventuallly, the cat’s patience paid off as it nabbed a gopher that made the mistake of peeking out of its burrow at the wrong time.

Trail cameras tend to render very poor quality images, but they do allow us to see things we otherwise might not, like the fire in this bobcat’s eyes. A highly reflective layer of cells known as the tapetum lucidum enables exceptional nocturnal vision for all felines.

The same trailcam recorded this beautifully colored gray fox – (Urocyon cinereoargenteus) a common predator here, but rarely glimpsed because of its nocturnal habits. Gray foxes are among the very few canids on Earth that can climb trees with ease.

A coati (Nasua narica) exploring an old barn. This one was unconcerned with my presence – these are not shy mammals. Coatis are native constituents of the fauna of the Sierra Madrean Ecoregion. Here, they are close to the northern limits of their range.

When mammals grow front claws to lengths like these, it can mean only one thing – that digging is a prominent part of their lives. Coatis use their flexible, sensitive noses to locate underground food sources (mostly insects, grubs, and pupae), then employ their stout claws to dig out dinner.

When they are not raiding gardens or gnawing on the electrical wires in the engine compartments of vehicles, rock squirrels (Otospermophilus variegatus) play a valuable role in the local ecology. Equally at home in the trees or on the ground, this species digs deep burrows to live in. By virtue of their relatively large diameter, rock squirrel burrows furnish secure underground retreats for a wide diversity of other creatures.

This young Mearn’s kangaroo rat (Dipodomys mearni) had become trapped in our (always empty) swimming pool. This species is abundantly distributed in the valley floor, providing food for many predators and playing a valuable role in the ecology of local native plant communities via seed consumption and seed distribution.

Coyotes (Canis latrans) are amazingly adaptable – they are among the few native mammals whose ranges have expanded considerably since the occupation of this continent by Europeans and other non-native peoples. They are also widely misunderstood and unjustly vilified by many people. Is ignorance bliss? Not in the case of the coyote.

I remember how thrilled I was to see my first javelina (Tayassu tajacu) – now I see them daily roaming through our bosque. This one had just finished taking a drink from the San Pedro River.

It would be a misnomer to apply the word “cute” to an adult javelina, but with respect to their tiny young, the adjective fits like a glove. Mother javelinas are both fearless and fierce when it comes to protecting their young, as all good mothers should be.

Desert cottontails (Sylvilagus audubonii) are quite common in this river valley, but they are not often seen due to their preference for staying in or near dense cover. Unlike precocial jack rabbits, cottontails dig burrows and care for their altricial young.

A Botta’s pocket gopher (Thomomys bottae) takes a quick, furtive look at the world of light. This mammal’s life is spent almost entirely in darkness. A keystone species, its role in our local ecology is of pivotal importance. I devoted an essay to this topic in The Life of the San Pedro River.

Here is what gives nightmares to any animals that think they are safe and secure deep in their burrows. Badgers (Taxidea taxus) are enormously powerful rapid digging machines, specialized to follow rodent burrows deep underground until dinner is served. They leave many holes in their wake as they roam large territories seeking food. Badger holes often plunge below the frost line. Their large holes can fit a wide variety of other animals and are used by numerous other species for shelter or brumation / hibernation dens long after the badgers leave them.

I will follow this post with a series of additional blog posts focused on birds, ophidians, and more in celebration of this new year of 2024.

A RAVEN’S UNFORGETTABLE COURTSHIP DISPLAY, RARELY SEEN!

“One thousand feet above the valley floor, a large bird cuts an arc across a universe of clear azure sky. The bird is black, so black that it pierces a hole in the heavens, a mysterious place where all light gathers to coalesce into an extraordinary being. It is a creature wrapped in a cloak that dines on light, a creature that melts into the darkness of midnight but lives to greet the morning sun. It is an exquisite merging of feather and form, a fusion of mind and voice that we know as the raven.”

That is how I opened the essay on ravens in my new book, The Life of the San Pedro River. I have nurtured an ever-growing fascination and respect for ravens since my teenage years. Here in southeastern Arizona, my wife and I share land with a pair of Chihuahuan ravens that we have known quite closely for the past nine years. They are Mike and Mavis. Their lives have been undergoing an exciting change during the past month.

Mike maintains a daily presence here, forever welcome. His mate is almost always close by.

For six consecutive years, Mike and Mavis raised annual broods of young ravens in a nest located in a mesquite tree only 110 feet from our home. However, during the past two years, they moved to a new nesting site on a neighbor’s property some 300 yards distant, again in a tall mesquite. We missed them!

Mike digging with his beak. Chihuahuan ravens commonly cache food items for later use. Some food is placed in the crotches of trees. Far more often, these birds dig holes, drop a morsel of food into the hole, then cover the food with an inch or two of soil. Equipped with exceptional minds, ravens have no trouble relocating their numerous, well-hidden caches, even weeks later.

Despite the fact that ravens have stout, formidable claws, I have never seen them use their feet for digging, as other birds do.

Four weeks ago, I looked out my office window to see Mike fly by with a stick in his mouth. He was not heading south towards the distant nest site, but instead flew about 100 feet to the north and lit in a mesquite, where he placed the stick. That got my attention! As I watched during the days that followed, it became clear that a new nest was being built on our property.

The pair bonding between adult ravens may be closer and longer lasting than any other North American birds. Mike and Mavis are together year-round; feeding, foraging, nesting, exploring, and sleeping as a pair. That’s Mike on the left; note his thicker neck, larger head, and bigger body in comparison to his female companion.

Watching ravens build a nest is a lesson in patience, determination, and tenacity. Branch after branch is carefully selected, then carried aloft to the tree. By “carefully selected,” I mean just that – if a stick is partially rotted or otherwise infirm, it won’t do. Each stick must be within certain parameters with respect to weight, thickness and length. Once a suitable stick is found, it is skillfully balanced in the beak for the flight to the nest, then placed in a manner that is anything but random. For three weeks, I watched as hundreds upon hundreds of sticks left the forest floor to become airborne, a reverse journey back into the canopy they had sprung from. A nest took shape, growing deeper day by day. Three weeks passed, then Mike and Mavis abruptly changed their behavior. Stick gathering  had been completed, so it became time to line the nest with soft, fluffy materials. Scouring the neighborhood, the ravens found lengths of discarded baling twine, clumps of horse and deer hair, even pieces of cardboard that they ripped from a box that had been stored in an open shed. Now fully complete, the nest awaits its purpose. Soon, Mavis will lay her eggs and a new generation of some of the most intelligent birds on Earth will come into being.

The newly constructed Raven Hilton, built in the branches of a velvet mesquite. If all goes well, we will soon hear new voices emanating from the nest. Hatchling ravens produce low-volume, unique sounds that rapidly increase in volume and complexity as they grow.

One morning during the nest-lining period, both ravens came gliding through the trees to land on the ground within a dozen feet of my wife and I as we were seated under the ramada. Some very delicate, amorous preening followed as Mike ran his beak through Mavis’s neck and chest feathers. The birds were conversing with one another as this took place, uttering a soft language known only to them, a language marked by the deep-seated intimacy of a life-long pair bond that can last more than a quarter century. The preening done, Mike ambled over to within a dozen feet of us. There, he began a courtship display, hoping to win his mate’s admiration and acceptance. He lowered his stance until his body was almost flat on the ground, then fanned his tail wide. He partially opened his wings and erected the feathers on the crown of his head. His sleek indigo-black body quivered as he made a series of soft, percussive snaps with his stout beak. We were very lucky to witness this, and even luckier to get a few photographs. Only a few scant minutes of each year are dedicated to such interludes in the lives of ravens, interludes that maintain the circle of life.

Mike performing his courtship display.

As I was just about to hit the “publish” button to launch this blog post, a sudden drama unfolded just outside my office window. A red-tailed hawk made the mistake of flying too close to the new raven nest. Mike took off at high speed, chasing and diving on the hawk relentlessly. Ravens are masters of flight, a fact quickly apparent to anyone who has watched such events unfold. With very quick, elegant turns, dives, and rolls he chased the raptor for more than 250 yards before finally returning to the nest site. I have watched this pair of ravens defend their nesting sites with great vigor and determination many times. They have given brave and vociferous chase to coyotes, bobcats, a gray fox, many hawks, and more over the years. Anyone reading this who has raised children should understand such actions. I was once charged – repeatedly – by a ruffed grouse defending its chicks. Mind you, that is a bird no larger than your average chicken. I know of a Montana grizzly bear that charged and bit a slow-moving locomotive three times after the train hit one of her cubs. Motherhood and the protection of one’s young are among nature’s most powerful and important forces.

For much more on these incredible, amazing birds, read the essay entitled “Mike and Mavis” in The Life of the San Pedro River

For an even deeper journey into the fascinating lives of ravens, I highly recommend these two books, written by Dr. Bernd Heinrich, an astute biologist and acclaimed author: Ravens in Winter, and Mind of the Raven.