Welcome To Our Fresh Newsletter Format 

We hope you like our new way to get our newsletter to you. As you look at this in your email you may think it is a short email, but look carefully at the end of the email and there should be a message like "Click here to see entire message." When you click, the entire newsletter should be visible to you.

Check our website for the most current information:

www.ajonaturalhistoryassociation.com

President's Message

Our little organization has been busy over the past couple of months. We have had some wonderful field trips and amazing lectures, all very well attended by our membership. Our bookstore has been well visited at the Mercado. As you will read, we will continue to have plenty to keep you nature nerds stimulated and engaged whether it be sitting comfortably in a talk or getting out on the trail.

With all this going on, I want to give a big Thank You to the volunteers that make this all happen. We have many ways to be involved ranging from being on our board to being a volunteer at our bookstore, or maybe volunteering to contribute some photos or an article to the newsletter. The possibilities are endless and the pool of talent in our membership is immense. This organization is all about its members and connecting people with the desert. Thank you for all you do.

-Vikki Jackson

(Photo of January 2026 Bluebird Mine field trip by V. Jackson)

Photo of Fall 2025 Crater Range field trip by K. King

Upcoming Events*

Field trips are free (unless state otherwise) for ANHA Members and open to non-members for $5.00 each participant.

Click on the event and it will provide you with more information.

• ANHA Lecture Series: Tanner Bland: Biodiversity, Evolution, and Native Sonoran Bees – A Search Through Time for the Roots of Desert Bee Ecology. Thursday, February 12^th 7pm 
  
  
• ANHA Field Trip: Discovering Patterns in the Desert: learning to see and understand. Friday, February 13^th 9am till 12pm
  
  
• ANHA Bookstore at the Saturday Mercado. Saturday, February 21st 9am till 1pm
  
  
• Deadline for submittals for the Annual Photo Show at the Chamber of Commerce in the plaza. Monday, February 23rd 3:00pm.
  
  
• Field Trip: Sear's Point Archeological Wonderland. Saturday, February 28^th 7am till 5pm  - Limited Space. Must Register!
  
  
• ANHA Lecture Series: Don Swann - Exploring Evolving Questions About Saguaro Cactus.Thursday, February 26^th 7pm
  
  
• Celebrating the Sonoran Desert Photo Show. March 3^rd-28^th
  
  
• Opening Night Celebration of the Celebrating the Sonoran Desert Photo Show. Tuesday, March 10^th 5pm till 8pm
  
  
• Tri-National Sonoran Desert Symposium. Visit our bookstore there!  March 9th - 12th, 2026. 
  
  

*Note: All membership meetings and lectures are being held in the Ajo Ambulance meeting room, 1850 N. Ajo-Gila Bend Hwy.

Photo by Dr. M. Johnson

Human Nature

By Dr. Mark D. Johnson

If you want to see Javelinas - stay in town or nearby, and check out the washes, aka wild animal highways.

If you want to see Elf Owls - head for the wilds south of the Scenic Loop Road.

Want to see bats? - When it warms up in the evenings this spring take a flashlight to the fountain pond at the golf course after sunset, or watch the roofline above the Oasis Cafe by the Plaza as twilight comes on in the evening.

Want to see some Crested Caracara? - Drive Hwy 86 and keep your eyes peeled near Sells.

Our part of the Sonoran Desert would be very different if humans had not been inhabiting this area for thousands of years. And without the mine in Ajo, and the associated need to access deep ground water here, wildlife would be much more sparse than it is. Watered yards and gardens, bird baths and other watering pans kept at ground level make for a higher density of wildlife in town than outside of it… for some kinds of life.  

Yes, humans are a part of nature, and always have been. Even when some cultures have tried to separate themselves from the natural world, they have never pulled it off. Yet, even those who agree with the concept of humans being a part of the natural world, many have very different ideas of what that means: everything from living simply to allow room for all living creatures to have a home, to the other end of the spectrum that “pollution is natural” because it is something that humans do naturally.

Keeping some of our wild lands free from too many humans is one way to preserve wildlife. Yet, I have seen (and HEARD) more of our native grackles (Quiscalus mexicanus) at the Bud Walker Park in one afternoon than I have in all 4 years combined of rambling around in the nearby desert. If you have seen squadrons of javelinas, I would betcha that most of those sightings have been in town. We live in nature, and we create aspects of it, wittingly or otherwise.

In addition to intentionally or inadvertently supporting Sonoran Desert wildlife by our water-using ways (think of doing some birding here without the “Lake Ajo” sewage treatment pond, or the golf course with its ponds, or the remnants of the now bulldozed “Highway Tank”), we are also agents of the Homogenocene*. 

As a species we tend to intentionally bring plants and animals with us that we like (e.g. thorn-free Peruvian mesquite trees), and unintentionally we also bring pests that decimate native ecosystems (e.g. Russian Thistle aka tumbleweed came to the Americas as contaminants in flax seed). Now, non-native grasses and stinknet have increased the danger of catastrophic wildfires in our precious Sonoran Desert. 

We plant water-hogging eucalyptus from Australia, lawn grasses from Eurasia, etc. … and then wonder why the ecosystems around us change, and some kinds of organisms go extinct. By bringing organisms from all over the world together we help create an homogenized world - and we lose diversity as a result.

I have been very pleased to see that the tree planting done by volunteers around town has been using  native trees and bushes, rather than the toxic oleanders some folks still plant. One can still see the fences at some houses around town with signs designating their yard as official “Wildlife Habitat” from back in the day when it was a thing. Perhaps it is time for an organization like the Ajo Natural History Association to resurrect such a campaign?

*Homogenocene (from old Greek: "homo" = same, "genos" = kind, "kainos" = new) is a term used to define our current ecological era, in which biodiversity is diminishing and ecosystems around the globe seem more and more similar one to another.

Long-eared Owl
Photo by V. Jackson

Christmas Bird Count Results

By Greta Smith

(Note from Vikki Jackson: Many of you were involved in the Annual Christmas Bird Count. Greta Schmidt from Cabeza Prieta NWR, one of the coordinators, reached out to give us an update on the results.)

Many thanks for participating in the Ajo-Cabeza Prieta Christmas Bird Count! I'm reaching out to provide a brief summary of the count. We had 21 participants, saw 69 species, and counted 2,129 birds. Mexican duck was a new addition to the Ajo circle, and white-throated sparrow had previously only been recorded as a count week bird, both great finds! The average number of species detected in the Ajo circle over the previous 10 Christmas Bird Counts was 67, so we were pretty much right on target for what's typical in our circle. I've included a table of the birds seen 1/2/2026 below.

Black-taied Gnatcatcher
Photo by H. Jorgenson

Black-tailed Gnatcatcher

by Hank Jorgenson

Here I sit supine in the lounge chair in the back yard dozing off, accomplishing nothing worthwhile. Suddenly my attention becomes focused on a series of harsh tssh tssh tssh calls from up in the neighbor's huge mesquite tree. Stirred from my torpor, I begin scanning the tree to see what is going on up there. Soon I discover what is making the sound. A tiny bird going tssh tssh is darting madly around in the tree never stopping for more than an instant, making it almost impossible to get a decent picture. Soon the little bird is joined by another one, looking almost identical. These birds were mostly gray with long black, rapidly flicking tails white underneath and along the edges. Upon consulting with my wife Dorothy, the bird expert, we concluded that the two birds were a pair of black-tailed gnatcatchers. I could only imagine how much I could accomplish in my life if I had only 1/100 as much energy as these little guys.

Black-tailed gnatcatchers are almost identical to blue-gray gnatcatchers except the call is different, the tail of the former has more white underneath, and the distribution/habitat is different. Both species are small, 4 to 5 inches long including the tail. Males have a black cap on the head during breeding season.

Black-tailed gnatcatchers are non-migrating and monogamous, males and females essentially spending their lives together. They work together building tiny cup nests usually about 5 feet above the ground in desert shrubs, although sometimes as much as 25 feet above ground mostly in paloverde trees, but sometimes in velvet mesquites or desert ironwood.

These nests, built from grass, plant fibers and spider webs, are lined with whatever soft materials can be found. Often nests are placed in masses of desert mistletoe. Breeding generally begins in April but may continue at a declining rate through May. Fledging generally starts in early summer, but it has been observed as late as September.

These birds are insectivorous and like a lot of such birds, they will go to hummingbird feeders (personal observation). In areas where cowbirds occur, nest predation from the cowbirds can result in a heavy toll on reproduction of gnatcatchers as well as other small birds that deposit eggs in cup nests. Cowbirds have been observed in all parts of Arizona.

Black-tailed gnatcatchers are found only in the hot deserts of the Southwest, mostly in the Sonoran Desert, which has a greater variety of small and medium shrubs and trees favored by the black-tailed gnatcatchers than the Mojave and Chihuahuan deserts. The preferred habitats for nesting and insect gleaning are dry washes bordered by a large variety of shrubs and trees as well as, strangely, the valley bottom flats dominated by creosote bushes.

Suitable habitat for black-tailed gnatcatchers in the Sonoran Desert of Arizona has substantially declined due to rampant urbanization in large areas. Even so, the species is not considered threatened. The town of Ajo supports a few pairs of black-tailed gnatcatchers due to a major wash passing through town as well as a few yards planted with suitable native vegetation. The almost identical blue-gray gnatcatcher is found only at higher elevations where precipitation is greater than in the desert and vegetation is dominated by chapparal and oak/juniper woodlands.

Desert Bighorn
Photo by B. Perry

Desert Bighorns

by Bill Perry

Hiking early one morning, as my wife and I approached the top of “A” Mountain in Ajo, Arizona, we came up over a ledge and encountered an unexpected local critter. There, not fifty feet from us and seemingly unbothered by our sudden arrival, was a young male Desert Bighorn Sheep. He looked at us, then slowly resumed grazing the small tufts of vegetation emerging from cracks in the rock. He seemed unperturbed. As he slowly nibbled along, my wife began sweet-talking him in the soft, soothing tones that she reserves for many of the desert fauna she encounters, “My, aren’t you the pretty one. You must be the most handsome guy in your pack.”

We also noticed the large new horns on either side of his head, indicating that he was probably a young male. He slowly moved away from us, starting down the steep, near-vertical side of the peak, still munching away. Large obvious gonads now further confirmed his gender.

Our Desert Bighorn Sheep (Ovis canadensis nelsoni) is also known in the Mexican half of the Sonoran Desert as “Borrego” or “Borrego Cimarron.”  (They’re the official state symbol of Baja California.)  Mature males may weigh up to 280 pounds and appear to be almost pure muscle. Females are slightly smaller, with more delicate horns.

Bighorn facts:

Their hooves are concave and elastic, allowing them to traverse near-vertical rocky cliffs with complete ease and grace.This allows them to rapidly outclimb a less-agile predator such as a cougar.

They eat all forms of desert vegetation, including, if truly hungry, cactus. As a result - unlike the Sonoran Desert Pronghorn - they are thriving in these drought conditions.

Like most of their large mammal relatives such as deer, elk, pronghorn and even domestic cows, Bighorns are ungulates, animals that stop to rest during the day, cough up some partially - chewed food, finish chewing and then swallow it.

Desert Bighorns, unlike our lone male, usually travel in small groups of up to ten, separated by gender.  During their late-fall mating season, males will engage in head-butting fights to determine who gets to breed the females.

Babies are born from January to April and soon begin to run in their own groups, detaching just long enough to nurse from mom. After that, they become somewhat independent, often traveling in pairs - or alone - as our young “A” Mountain male. Happy trails, Bighorns!

Membership Information

Membership in the Association is open to everyone.

Why join? All membership fees directly support ANHA's mission of providing education about and opportunities to engage with the Sonoran Desert around Ajo.

One way ANHA does this is by its annual lecture series. Lecturers often travel a significant distance to share expert knowledge in their field of specialty, and ANHA covers those costs while keeping lectures free and open to the public.

Fees also support field trips and workshops, most of which are offered at no cost, and members are the first to learn about upcoming events and have the opportunity to sign up first for activities with limited space.

Membership Dues: Annual Individual: $15. Annual Family: $25. Lifetime Individual: $80. For membership questions, email Vikki at president@cabezaprieta.org.

We are working on a way to join and pay for a membership online, but in the meantime you can pay for memberships at our Bookstore at the Saturday Mercado or our membership meetings and lectures or mail in the form to:

Ajo Natural History Association
P.O. Box 234
Ajo, Arizona 85321-0234

The form may be downloaded and printed using the following link: AJO NATURAL HISTORY MEMBERSHIP.

Membership Information

Name(s)______________________________Date ___________ 

Email ________________________________

Phone _____________________________

Renewal ____ New ____

Individual: $15.00 _____

Family: $25.00 ______

Lifetime: $80.00 per individual, $150.00 per family _____

Ajo Natural History Association is a 501(c)(3) Nonprofit Organization
PO Box 234 Ajo, AZ 85321