Archive for the ‘Entries by Sheri Williamson’ Category

Throwback Thursday: Ocelots in the Sky Islands

By

Wednesday, May 15th, 2013
Ocelot

Ocelot © C. Allan Morgan

Throwback Thursday: Ocelots in the Sky Islands by Sheri Williamson

Originally Posted May 23rd, 2012

A little cat has been making big news in Arizona. Back in November 2009, a remote camera in the Huachuca Mountains, placed by volunteers with Tucson-based Sky Island Alliance, captured a blurry but recognizable photo of an Ocelot. This was the first solid evidence for the species’ presence in Arizona in almost 50 years.

Tantalizing to be sure, but anyone who spends time in the wild knows just how rare it is to see even the relatively common Bobcat. That’s why it was so exciting to hear on February 8, 2011 that dogs had treed an Ocelot in the Huachucas. The animal, which appeared to be a healthy adult male, was allowed to go on its way unharmed after photo and video documentation. It was much grayer and shorter-nosed than the more familiar tropical subspecies, as befits an Ocelot of the colder, more arid Southwest.

Four months later, the Monument fire swept through the southern part of the Huachuca Mountains, causing many to fear for the life of this very special feline neighbor. The story recently took an optimistic turn in late April, when a private citizen’s remote camera captured new Ocelot photos in the Huachucas. These are being examined by biologists with the Arizona Game & Fish Department and compared with the 2011 photos. Whether or not the spot patterns match, we know that there is still at least one Ocelot roaming Arizona’ssky islands.”

Less than 40 miles as the raven flies from the Arizona encounters, other remote cameras at El Aribabi Conservation Ranch in Sonora, Mexico have recorded multiple Ocelots and at least one Jaguar in addition to Bobcats and Mountain Lions. The bigger felines can no longer travel freely where the border fence has been completed, but I’m glad there’s room for the Ocelot to slip through.

-Sheri Williamson

Generals on the March

By

Tuesday, November 20th, 2012
Horse Lubber Grasshopper

Horse Lubber Grasshopper © Sheri Williamson

Generals on the March by Tom Wood and Sheri Williamson

A generous late summer “monsoon” season in the desert grasslands of the Southwest translates to a fall population boom for many wildlife species. Some of the “boomers” are easier to see than others, including the gigantic grasshoppers known as Horse Lubbers. They’re one of the two largest grasshoppers in North America (the other being the Eastern Lubber). A mature female may be 2.75 inches in length and weigh as much as three male Black-chinned Hummingbirds!

Many of our human neighbors here in southeastern Arizona know the Horse Lubber as the “Mexican General,” a colloquial name inspired by its bold pattern of bright yellow accents on a background of black and dark green, like a high-ranking officer in full dress uniform. Grasshoppers often have colorful hindwings, and a few are quite colorful on close inspection (the Rainbow Grasshopper, for example), but no other grasshopper in the Southwest is as in-your-face conspicuous as the Horse Lubber.

Like many desert insects, Horse Lubbers depend on the short-term abundance of food resulting from the late summer rains. When “monsoon” thunderstorms transform the desert into a virtual all-you-can-eat salad bar, lubber nymphs hatch from eggs laid the previous year and begin to gorge themselves. As they reduce the food supply in one area, they march on to greener pastures, passing through several instars (growth stages) as they go. Early instars are chunky and wingless. By the final stage, they have slimmed down and grown wings for greater mobility.

The lubber boom might seem to be a boon for predators, but it pays to be suspicious about a critter that’s abundant, conspicuous, and easy to catch. You’ve probably already figured out that the gaudy attire and sluggish behavior of Horse Lubbers are aposematic, a warning to potential predators of well-armed prey. Like Monarchs and Pipevine Swallowtails, the big ‘hoppers are infused with toxic chemicals that make them unpalatable, but making a predator nauseous is a Pyrrhic victory. The preferred outcome is not to get eaten in the first place. Threatened lubbers start by hissing and flashing their bright salmon-red hindwings. If that doesn’t work, they’ll spray their attackers with noxious chemicals, like six-legged skunks. It doesn’t take too many such encounters for predators to learn not to mess with lubbers. Our pet chickens enthusiastically chase after any small, cryptically colored grasshoppers that find their way into our yard, but they give the big black ones a wide berth.

We think of grasshoppers as herbivores, but Horse Lubbers like a little meat in their diet. They’re not fussy; carrion is fine fare, and they’re not above cannibalism. As with skunks, the sluggish and fearless behavior of lubbers makes them vulnerable to traffic. Those that don’t make it across the highway may become “road food” for their traveling companions. In fact, their chemical defenses are so successful that about the only animal that can stand to eat a Horse Lubber is another Horse Lubber. As our collegue Pete Corradino discovered, Loggerhead Shrikes in Florida will eat Eastern Lubbers after letting them “mellow” a bit to break down the toxins, but we haven’t observed this behavior in Arizona. Maybe Horse Lubbers are “spicier” than their southeastern cousins?

Photo Essay: Banding Hummingbirds

By

Thursday, October 11th, 2012

Photo Essay: Banding Hummingbirds by Sheri Williamson & Tom Wood

Violet-crowned Hummingbird

Violet-crowned Hummingbird in hand © Sheri Williamson & Tom Wood

Most of what we know about the lives and travels of hummingbirds comes from hands-on research. As with other birds, banding (a.k.a. ringing) is the most important tool for understanding hummingbird populations, longevity, reproduction, and migration. In the U.S., banding of wild birds is conducted under the authority of the Bird Banding Laboratory (BBL), a federal agency. The BBL issues permits and bands and manages the data collected on millions of banded birds, from Calliope Hummingbirds to California Condors.

hummingbird

Trapping team members bag a captured hummingbird © Sheri Williamson & Tom Wood

The Southeastern Arizona Bird Observatory (SABO) has been banding hummingbirds on the San Pedro Riparian National Conservation Area since 1996. To capture these intelligent and suspicious birds, we bait a custom-made trap with a sugar-water feeder. When hummingbirds come to feed, the trapping team trips a switch that drops a soft curtain around both feeder and birds. Incredibly, some birds will escape by ducking out under the falling curtain. The trapping team gently removes captured birds from the trap and places them in soft holding cages (actually repurposed lingerie washing bags) for transport to the banding table a few yards away.

Black-chinned Hummingbird

Selecting a band for a female Black-chinned Hummingbird © Sheri Williamson & Tom Wood

At the table, the bander removes the bird from the bag and checks for a band. If the bird is already wearing one, the number is recorded. The oldest hummingbird in SABO’s study, a female Black-chinned, wore her band for at least nine years. For “new” (unbanded) birds, the species and sex will determine what size band is likely to be the best fit. The bander closes the tiny, uniquely numbered band around the leg using special pliers and checks the fit. The bands arrive from the BBL as thin sheets of flexible aluminum printed with a unique series of numbers and guidelines for cutting. It’s up to the bander to cut strips of bands out of the sheet, smooth the edges, cut each band to the appropriate length for the final diameter, and form it into a tiny ring.

Black-chinned Hummingbird

Measuring the bill of a female Black-chinned © Sheri Williamson & Tom Wood

The lengths of bill, wing, and tail provide basic information about the individual and help to confirm the identification. Each bird is also examined for plumage condition, fat (essential fuel for migration), and color and location of pollen (clues to important natural nectar sources). Possible breeding females are given a quick “obstetric exam” to check for the presence of a developing egg, which will be visible through the wall of the abdomen as a pale bulge.

Hummingbirds

Hummingbirds wait in holding cages while the scribe records data © Sheri Williamson & Tom Wood

The team’s scribe records each bird’s “vital statistics” on a data sheet while birds in holding cages wait their turn on a carousel made from repurposed music stands.

Anna’s Hummingbird

Weighing an Anna’s Hummingbird © Sheri Williamson & Tom Wood

The bird is then wrapped in a piece of translucent netting and weighed on a spring scale. A lean male Black-chinned Hummingbird weighs just under 3 grams, slightly more than a penny, while the average male Anna’s weighs over 4 grams, a little less than a nickel. During migration, their weight can increase by more than 50% as they store fat to fuel their epic journeys.

Broad-billed hummingbird

A female Broad-billed on her “launch pad” © Sheri Williamson & Tom Wood

Once all the documentation is complete, each bird is offered a drink of sugar water and placed in a waiting hand for release. With luck, it will return many times to tell us more about its life, its species, and the environments we share.

SABO’s hummingbird banding sessions are open to visitors. Banding season is over for this year, but next year’s schedule will be posted on the online calendar of events.  

 

Rattlesnakes: Don’t Fear the Viper

By

Friday, August 10th, 2012

Rattlesnakes: Don’t fear the viper by Sheri Williamson

The return address on the envelope was in New York City.

I’d love to visit Arizona to see the hummingbirds, the letter began, but I’m wondering if I should be worried about rattlesnakes.

Thanks for your concern, I typed, but the rattlesnakes are doing just fine.

I immediately apologized for the flippant response and assured the writer that it’s all about what you’re used to. Venomous snakes don’t bother me because they’re something I live with, but muggers and pickpockets would make me think twice about exploring the Big Apple.

I added our standard educational spiel about rattlesnakes:

  • They’re beautiful and interesting creatures in their own right.
  • Being shy and mainly nocturnal, they’re seldom encountered by visitors.
  • They’re more afraid of us than we are of them.
  • You’re more likely to be hit by lightning than die from snake bite.
  • The typical snake bite victim is young, male, and under the influence of alcohol and/or recreational drugs.

Start your visit at the Arizona-Sonora Desert Museum in Tucson, I suggested. It’s a great place to get acquainted with all kinds of desert wildlife, including snakes, in a safe, non-threatening environment. And please let us know if you need any additional help in planning your trip.

We never heard from her again.

Mojave Rattlesnake

With nowhere to hide, a frightened Mojave Rattlesnake adopts an S-curve striking stance. © Sheri Williamson

Rattlesnakes are such icons of the desert that it’s hard to convince the average visitor to the Southwest that they’re unlikely to see a live one except through the glass wall of a zoo exhibit. Sadly, most wouldn’t have it any other way. It’s a shame that the demonization of snakes in our culture has made it almost impossible for people to enjoy them the way we enjoy birds, mammals, and even most other reptiles.

Though many people wouldn’t use this adjective, we consider ourselves blessed with viper diversity here in the Southwest. Our 13 rattlesnake species (of 16 found north of Mexico) range in size from the dainty Massasauga to the burly Western Diamond-backed and Mojave. They come in colors and patterns as varied as the environments they inhabit: black, rust, pink, olive, blonde, and gray, barred, banded, blotched, mottled, speckled, and of course diamond-backed. The legendary Sidewinder is a rattlesnake, too, though one with an unusual mode of locomotion adapted for sandy deserts.

Rock Rattlesnake

A Banded Rock Rattlesnake retreats from an intruder © Sheri Williamson

Excellent camouflage plus sluggish behavior help to conceal rattlesnakes from both their prey and potential predators. Of course, you can’t avoid something you can’t see, and this rightly puts many desert travelers on edge. You could walk right by a rattler nestled under a bush or tucked away under a rock ledge and never be aware that it’s there. It’s a dangerous myth that they always rattle to let you know they’re there. They may not be aware of you until you’re too close, or they may opt to keep quiet if they don’t sense immediate danger. I’ve had a couple of close calls with quiet ones when traveling off the beaten path (another good reason to stick to roads and well-marked trails).

For such well-armed creatures, rattlesnakes are surprisingly timid. They’d prefer to avoid a confrontation with you, but most are so heavy-bodied that they can’t move very fast. Larger specimens in particular tend to stand their ground when threatened and wait for you to retreat. The appropriate response to seeing one in the wild is to stop and, if necessary, back off to a distance at which it feels comfortable (you’ll know because the rattling will stop). If you only hear one, the safest response is to freeze and determine where it is. Once you locate the snake, back slowly away until it stops rattling. Then you can enjoy it from a distance comfortable to both parties and give the snake enough room to make its getaway.

Though snakebites are extremely rare, it’s important to know what to do and what not to do. Despite what you may have heard about cutting, suction, tourniquets, ice, and/or whiskey, you risk complicating the injury and delaying expert treatment if you try any of these discredited first aids. Snakebite specialists now recommend just washing the site of the bite, immobilizing the affected area (below the level of the heart, if possible), and getting to a hospital as soon as possible. Our friend Alan Tennant, author of The Snakes of Texas, liked to emphasize this point by jingling his car keys when asked what snakebite kit he recommended.

Another dangerous myth about snakebite is that it’s important to catch or kill the snake and bring it to the hospital. All rattlesnake bites are treated with the same antivenom, so it’s not crucial for the ER staff to know which species it was. Leave the snake where it is and use your Audubon Guides app to identify it.

Rattlesnakes may not live up to their mythical reputations, but encountering one is still a thrill and a privilege. Be safe, and savor the experience.

Ocelots in the Sky Islands

By

Wednesday, May 23rd, 2012

Ocelot © C. Allan Morgan

A little cat has been making big news in Arizona. Back in November 2009, a remote camera in the Huachuca Mountains, placed by volunteers with Tucson-based Sky Island Alliance, captured a blurry but recognizable photo of an Ocelot. This was the first solid evidence for the species’ presence in Arizona in almost 50 years.

Tantalizing to be sure, but anyone who spends time in the wild knows just how rare it is to see even the relatively common Bobcat. That’s why it was so exciting to hear on February 8, 2011 that dogs had treed an Ocelot in the Huachucas. The animal, which appeared to be a healthy adult male, was allowed to go on its way unharmed after photo and video documentation. It was much grayer and shorter-nosed than the more familiar tropical subspecies, as befits an Ocelot of the colder, more arid Southwest.

Four months later, the Monument fire swept through the southern part of the Huachuca Mountains, causing many to fear for the life of this very special feline neighbor. The story recently took an optimistic turn in late April, when a private citizen’s remote camera captured new Ocelot photos in the Huachucas. These are being examined by biologists with the Arizona Game & Fish Department and compared with the 2011 photos. Whether or not the spot patterns match, we know that there is still at least one Ocelot roaming Arizona’ssky islands.”

Less than 40 miles as the raven flies from the Arizona encounters, other remote cameras at El Aribabi Conservation Ranch in Sonora, Mexico have recorded multiple Ocelots and at least one Jaguar in addition to Bobcats and Mountain Lions. The bigger felines can no longer travel freely where the border fence has been completed, but I’m glad there’s room for the Ocelot to slip through.

-Sheri Williamson

Blithe Spirit of the Prairie

By

Friday, May 11th, 2012
Horned Lark Birds

Horned Lark © 2012 Sheri L. Williamson

Hail to thee, blithe Spirit!
Bird thou never wert-
That from Heaven or near it
Pourest thy full heart
In profuse strains of unpremeditated art.

–Percy Bysshe Shelley, Ode to a Skylark

Though it doesn’t share the soul-stirring, poet-inspiring vocal talent of its famous cousin, there’s much to love about the Horned Lark. That face, for example. The upswept tufts of black feathers worn by adult males combined with the striking face pattern are worthy of a superhero or luchador.

Our only native American Lark brightens up farm fields, pastures, and golf courses as well as prairies, deserts, and alpine and arctic tundra. It’s one of the world’s most widespread and adaptable songbirds, with various subspecies nesting from northern Canada and Alaska southward to tropical Mexico and across northern Europe and Asia (where it’s known as the Shore Lark).

This dapper songster sings in flight, a behavior shared not only by the Sky Lark of Europe and Asia but by a few other North American songbirds. If you guessed the Lark Bunting and Lark Sparrow are two of these, you’d be right, but the dun-colored Cassin’s Sparrow of the southwestern grasslands also delivers its trilling song from high in the sky.

-Sheri Williamson

Desert Chipmunk

By

Tuesday, April 5th, 2011


The high deserts of southeastern Arizona are a little short on chipmunks. Even the tough little Cliff Chipmunk seldom strays far from the forests of the Chiricahua Mountains (except for a few pioneers that somehow made it to the Huachuca Mountains, but that’s a topic for another post). So what’s a tiny squirrel with racing stripes doing in our desert garden? It’s the chipmunk’s doppelganger, Harris’s Antelope Squirrel. They’re a bit larger and rounder than true chipmunks and lack facial stripes, but their behavior is strikingly similar.

This is a very special neighbor, unique to the Sonoran Desert region. Their genus name, Ammospermophilus, means “sand seed lover,” but Harris’s Antelope Squirrels are as comfortable in rocky deserts as sandy ones. Sure, they stuff their cheek pouches with high-priced seed intended for the birds, but you can get away with some petty theft when you’re that cute. Anyway, they don’t take nearly as much as the relatively enormous Rock Squirrels, and they tuck their plunder safely away in their burrows instead of burying it in our flower beds. (When it finally does rain, sprout volcanoes erupting in our hummingbird garden mark “Rocky’s” forgotten seed caches.)

The three other antelope squirrels are just as adorable: Nelson’s (an endangered resident of California’s San Joaquin Valley), Texas (western Texas, eastern New Mexico, and north-central Mexico), and White-tailed (western New Mexico west to southeastern California and southern Baja California north to southeastern Oregon and southwestern Idaho). Keep an eye peeled for them on your next desert camping trip.

Hasta La Vista, Cranes

By

Thursday, March 17th, 2011

It’s that bittersweet season when we welcome incoming migrants and say goodbye to many of our winter residents. None of our “snowbirds” are missed more than the Sandhill Cranes. Over 20,000 spent this winter at Whitewater Draw Wildlife Area, a state-owned refuge in the Sulphur Springs Valley.

Over this very dry winter, the playa lake where the cranes roost gradually disappeared. Roosting in water offers some protection from nocturnal predators such as Coyotes, Bobcats, and even domestic dogs and cats. The shrinking lake left the cranes more vulnerable, and with the departure of most of the flock the laggards can no longer count on safety in numbers for protection from Golden and Bald Eagles in the daytime.

All around the lake are piles of gray feathers. You’d have to perform a forensic examination of each pile to determine cause of death, but one accessible cluster included wing feathers that looked as though they had been snipped off with pruning shears. The bill of an eagle doesn’t have edges sharp enough for that, but a Coyote’s shearing carnassial teeth do.

In the pile were feathers stained brown from the “body painting” they do during the nesting season. Family bonds in cranes are strong. I mourned for the loss to this bird’s mate and offspring, but somewhere there’s a Coyote and probably some smaller scavengers who were celebrating with full bellies.

Sanctuary

By

Wednesday, January 26th, 2011

At my Sunday sanctuary the sermons are long and loud and the choir numbers in the thousands. Each Sunday we visit nearby Whitewater Draw Wildlife Area, winter home to over 20,000 Sandhill Cranes, to watch the cranes and answer the public’s questions about them. The cranes leave the shallow playa lake at first light each morning and fly fifteen to twenty miles to the valley’s corn fields. The corn has been long since harvested but the mechanical harvesters leave plenty behind for the cranes and they spend the morning gleaning the farmer’s fields, fertilizing as they go. I must admit, I am rarely there for the morning flight, but I know that by noon the cranes will have filled their crops and begin winging back to the playa lake. And I will be there waiting for the mid-day flight.

From the observation platforms at the wildlife area we scan the skies for what looks like distant puffs of smoke on the northern horizon. Gradually these dark clouds resolve into dots recognizable as flock after flock of returning cranes. Eventually we hear the distinctive bugling call ringing through the cold winter air and soon the air is full of cranes as these graceful four foot tall birds begin to wheel and drop to the edge of the shallow water. They drop their long legs and raise their heads to slow their airspeed until they reach stall speed and begin to slowly parachute to the ground.

Within the flocks of thousands it is easy to discern the fundamental unit of crane society, the family. Little groups of two to four cranes, the adults and last year’s young, fly together. Sometimes we can hear the high cheeping of the youngsters that haven’t yet grown the long trombone-shaped syrinx required to make the bugle. The cranes spend the rest of the day relaxing, digesting their corn and just loafing.

Next month the cranes will begin to head north. Several years ago we were lucky enough to spot a crane wearing satellite transmitter. We noted the number on the transmitter and, with a little detective work, we were soon in touch with the researcher who had tagged the bird. He sent us a map that showed our bird’s travels and we were delighted to see that the bird we had spotted was one of the approximately 10% of the Lesser Sandhill Cranes that travel across the Bering Strait to Siberia to nest, a flight of over four thousand miles. The departing of the Sandhill Cranes is bittersweet. I miss our Sundays together but if the cranes are headed north, can the arriving Swainson’s Hawks, warblers and hummingbirds be far behind?

Attack of the Cactus

By

Friday, January 14th, 2011

Visitors to the desert worry about encountering rattlesnakes, scorpions, killer bees, and other formidable creatures, but in my experience it’s the plants that’ll get you. The defensive arsenal employed by much of our perennial and woody flora includes a wide variety of spines, thorns, and chemical defenses. Though these are aimed mostly at discouraging herbivores, they don’t discriminate between the mouth of a Mule Deer or Javelina and the skin of a human being.

I recently had the most painful encounter of my life with one of my prickly desert neighbors, and (not surprisingly) it was entirely my fault. One night at about 11 p.m., our dog started giving her Javelina bark. Usually I ignore these alerts, but this one was followed by the clatter of pig-like snouts tipping the metal trash can where we store our bird seed.

A short burst from the garden hose scattered the nearest members of the herd, but in the dim light from the porch I could see several other Javelinas snuffling obliviously around the feeder area. I charged down the steps, grabbing a leaf rake on the way, and rushed the marauders. Most bolted away, grunting and squealing in alarm, but one found itself trapped behind a bush and tried to butt its way through the picket fence. Hoping to give the critter good reason to avoid our yard in the future, I swung the leaf rake toward its hindquarters. The rake missed, but my hands connected with a Tree Cholla (Opuntia [Cylindropuntia] imbricata).

Chollas are cousins of the prickly pears, but with narrow cylindrical stems instead of broad, flat pads. They’re among the prickliest of all our cacti, with dense clusters of long spines protecting their succulent flesh. The impact drove a number of these spines deep into my hands.

I dropped the rake and hurried back into the house for first aid. The right hand took the worst of it and was positively bristling along its pinky side. Let me tell you, the spines hurt much worse coming out than going in. Their surfaces are covered with backward-pointing scales, making them more like porcupine quills than rose thorns. It takes some force (plus pain and blood loss) to extract the larger ones from the skin. This tenacity enhances the secondary function of the spines, which is to aid vegetative reproduction by attaching stem sections, or joints, to passing animals. Once separated from the mother plant, each cholla joint can take root and form a whole new clone. I suppose I was lucky not to come away with big chunks of cholla attached to my hand instead of a few dozen spines.

This particular cholla was a tiny seedling when we moved into our house 15 years ago, and the only member of its species inside the fenced portion of our property. Chollas are popular nesting sites for Curve-billed Thrashers and Cactus Wrens and produce gorgeous flowers, so I kept putting off moving it to a safer location outside the fence. No more. As soon as my hands heal, I’ll carefully transport the mother plant and all its loose joints to a new home where we won’t cross paths in the dark of night. —SW