Monday, October 12, 2015

Reptile Ramble--Close up and Personal

I have written here many times about Reptile Ramble, the educational show we present at Tohono Chul Park in the warm weather. The program is helmed by two professional scientists who are assisted by two or three docents each week, and sometimes I'm lucky enough to be one of the docents.

The aim of the Ramble is to demystify snakes for our audience, and demonstrate why no one ever need fear them. At the same time, we introduce our visitors to many of their local neighbors, including lizards, amphibians, turtles, and four to six live snakes, usually including rattlesnakes. Last week I was one of the assistants, and was fortunate to demonstrate my favorite snake, Leo the common kingsnake. A visitor took a video of my presentation, though it was so windy the sound is very bad. Still and all, this is a good idea of what Reptile Ramble is like, on the docent's side. 

Saturday, July 25, 2015

Amazing Lesser Nighthawk Mother

Lesser nighthawks, which are very common in the Tucson area this time of year, are often seen soaring over the desert in the evening. During the day, they can occasionally be found roosting or nesting on the desert floor. Yes. Nesting. On the bare ground, often with no more shade than a creosote bush. 
As this photo shows, they are very well camouflaged, and that apparently serves them well.

Despite their name, nighthawks are not raptors; they are insect-eaters, and soar in the evening, gathering flying bugs into their very wide mouths with the help of "whiskers." The young are semi-precocial, which means that after they are hatched they do not need the constant care of a parent, as many nesting birds (doves, robins, etc.) do, but can move about and hide. They still depend on their parents, however, to bring them food until they are strong enough to fly on their own. 

When a birder and I saw the nighthawk today on our bird walk, she seemed fidgety. We wondered if it was due to all the bugs brought out by the extreme humidity, but apparently she was just getting ready to resettle herself and turn her eggs:

 Which she did, and which we were lucky enough to observe and videotape. By the way, birds such as nighthawks and doves that nest in the desert sun in the summer do so to keep their eggs COOL.

Here's the video:

Wednesday, July 08, 2015

White-winged babies everywhere!

Anyone who knows me or has followed this blog for any length of time knows that I LOVE LOVE LOVE white-winged doves. In our new house, there are several white-winged nests in various locations, and I've been seeing fledglings everywhere. Here are photos of three of the latest white-wingeds to grace the world. They are very unassuming and kind of geeky-looking, but so shy and sweet. Click here for the rather alarming tale of an extremely klutzy white-winged baby.

This little guy has been hanging out with the pottery and ceramic ducks on the wall of my private patio
And these little beauties have been making themselves invisible among the rocks on the edge of the front porch

Tuesday, June 23, 2015

Late Spring, Early Summer Beauty at Tohono Chul Park

We have gone from a relatively cool spring to a suddenly and ferociously hot summer, with the Monsoon fast approaching. Before it gets here, I want to share some of the beautiful things I've seen in the Park in the last few weeks:

You may have to look carefully to see the mama hummer sitting on this nest, which is directly on top of another nest in which someone--probably the same bird--recently fledged two babies. It is a pent-nest, if you will.

Below is a beautiful white-winged dove perched atop a blooming agave:

And a Gila woodpecker on nearby agave blossoms:

My last still photo is of two adorable, sleepy screech owls who have been roosting in the tree outside the Museum Shop:

 And finally, here's a video of a beautiful, very long gophersnake I saw meandering across the main path near the old penstemon garden. Even if you don't like snakes, just take a moment to watch its grace and fluidity:


Fierce Ground Squirrel Attacks, Kills, and Eats Longnose Snake!

This morning at Tohono Chul Park, some other docents and I watched a round-tailed ground squirrel attack, kill, and start to eat a longnose snake. All of us were flabbergasted; we think of these little rodents as extremely cute, harmless creatures whose only encounters with snakes occur when snakes go into their burrows and eat their young. It turns out the story is way more complicated, and as I found out while researching this, ground squirrels are well-known as eaters of carrion, birds, and snakes, even, apparently, rattlesnakes.

We did not see the beginning of the attack, but the snake was still moving when we began watching. After it was clearly dead, the squirrel began tearing through the snake's skin and biting off, then eating small pieces. After a while the squirrel began to drag the snake away, perhaps to pull into its burrow so the young squirrels might enjoy a treat?  I like to imagine a future race of pumped up killer ground squirrels rampaging through the desert. The actual truth is perhaps not so far-fetched. Here is the sequence as I photographed it.

For more on longnose snakes, click here. Another story about round-tailed groundsquirrels can be found here.

And finally, I managed to upload my video of this event. (June 23, 2015).

Thursday, May 28, 2015

Tale of a Lost Tail

The Desert Spiny lizard (Sceloporus magister), is among the most prominent creatures greeting visitors at Tohono Chul Park in the warm weather. Big, bold and beautiful, with striking colors and eye-catching behavior (these lizards, especially the males, frequently do pushups to advertise their fitness and attract mates), spinies say "Sonoran Desert" as surely as does the saguaro.  
Like other members of the Iguanid family (and other lizards, including geckos), a desert spiny can lose its tail to a predator in a process called autotomy, in which the tail breaks along a fracture plane between two vertebrae. Studies have shown that the lizard is handicapped for some time afterward while it grows a new tail, but it is obviously much better off  than if it had been eaten by the predator!

The tail that regrows is not the same as the original, however. Instead of new vertebrae for support, the regrown tail is composed of cartilage, with long muscles running its length (rather than shorter sets of muscles, as in the original tail). Studies have shown that the new tail does regrow nerves, though it is not known how they compare with the originals.
Above is a photo of a beautiful male spiny I saw at Tohono Chul Park this week, who had fairly recently lost his tail. The photo below more clearly shows the cartilagenous new growth. For a photo of an intact male and the female he has just mated with, see the bonus question in my recent nature quiz

Sunday, May 10, 2015

Late Spring Nature Quiz

This is our first nature quiz in quite a while. Here are five photos of plants and animals that are found in the Arizona Upland portion of the Sonoran Desert. Can you identify them? (Note that all photos were taken at Tohono Chul Park.)

1. This extremely fragrant plant is attractive to bees, butterflies, and human noses. What is its common name?

a) Kidneywood
b) Bladderwort
c) Spleen sticks
d) Herbert

2. This photo graphically presents three icons of the Arizona Upland. What are they?

3. What are the brilliant neon blue fish in this photo?
a) Blue Tetras
b) Cactus Crappies
c) Desert Pupfish

4. What in the world made these odd sandy excavations?

5. What kind of lizard is this? Is it male or female?

1. This is kidneywood (Lignum nephriticum), a fairly common shrub of the arid southwest. Its bark was used traditionally as a diuretic, hence its name. The flowers have a beautiful, bright sweet scent that becomes stronger when they are heated by the sun.

2. This photo shows a white-winged dove and Gila woodpecker enjoying the blossoms of a saguaro cactus. The saguaro is indeed an icon of the Sonoran Desert, as this is the only place in the world where it grows (and mostly in the Arizona Upland). The white-winged dove is an important pollinator of the saguaro, and the Gila woodpecker is well-known for making holes in saguaros that are used as nests.

3. These small, beautiful fish are endangered Desert Pupfish, which are kept as breeding populations by both Tohono Chul Park and the Arizona-Sonora Desert Museum. In spring, when the weather begins to get warm, the males show their sexual readiness by turning this brilliant shade of neon blue. 

4. These small depressions, or "pits," are made by antlions, tiny insect larvae that trap and eat ants. Each pit is created in loose sand by a larva, which then waits at the bottom for an unwary ant to fall into the trap. If the ant should regain its footing on the slide down, the larva throws sand up at it, usually sending it tumbling to the bottom where it becomes a meal.

5. This beautiful reptile is a female Desert Spiny Lizard (Sceloporus magester). When she is sexually mature, her head turns rosy pink to orange. Her better half has beautiful bright colors on his back and his belly. These are the large lizards often seen doing "pushups," which is the male's way of displaying his colors to females and rival males.

What do you suppose these guys have been up to? Please post your guess--or, even better--what you imagine they are thinking, in the comments.

5 points: You must be a nature docent!
4 points: You are at home in the desert.
3 points: You think the desert is beautiful, but would never spend the summer here.
2 points: You guessed randomly, right?
1 or 0 points: You'd really rather stay indoors.

Wednesday, April 29, 2015

Snake sex!

You've probably seen a photo or video of two snakes standing on their tails, intertwined, swaying back and forth, and may have thought this was a picture of snakes copulating. Nothing could be farther from the truth--when two snakes engage in this sort of "dance," as it is called, they are most likely males engaged in ritual combat. 
Oregon rattlesnakes, via Wikipedia
 The snakes I have observed having sex are much more sedate: generally they lie next to one another, with the male's tail wrapped around the female, holding their bodies close together while the male inserts his hemipenes (two penises) into the female's cloaca. The beautiful kingsnakes (Lampropeltis splendida) below began their romantic activities in the afternoon a couple of days ago, and I was told they were still together at sunset, but were gone by the next morning.

Photo by RobandUrsula Garrwald
The pair of western diamondback rattlesnakes (Crotalus atrox) in the photo below began copulation during a live music show at Tohono Chul Park one Sunday afternoon, and were still at it when I took the photo the next day. I was told that the female occasionally wandered off (to eat?) and then returned to resume activity.

Here is the possible outcome of such amorous activity: several baby diamondbacks from a group of eight that were born in a hole underneath an organpipe cactus a few months later, not far from the scene of the mating.

Note that the baby rattlers are so young their eyes are still cloudy

Friday, April 24, 2015

Do Hawks Fly for Fun?

On a beautiful spring day early this week my docent buddies and I were roving at Tohono Chul Park, enjoying the weather and the beauty all around us. Our resident pair of Cooper’s hawks seemed to be roving too--soaring from one end of the Park to the other, sometimes seeming to chase each other, sometimes simply moving in the brilliant blue sky in perfect synchrony. One of my friends, a retired scientist, speculated on what the birds were up to--was this a mating ritual, perhaps, or were they competing for food? They have already started a nest, so mating seemed unlikely to me, and there didn’t seem to be any competition or hunting going on. I remarked that they just seemed to be having fun, to be told by my friend that I was veering dangerously close to anthropomorphism.

I’ve written about this topic previously, and invite you to read the earlier post and the lively comments it engendered. I believe that invoking anthropomorphism is a defense mechanism used by those who study and sometimes harm animals to suppress their own natural empathy. Anyone who has ever had a pet has certainly seen a full range of emotions and behaviors exhibited by the pet, from love and excitement to fear and even deceit. I’m quite sure that wild animals too experience these feelings and perform these behaviors. I will never forget the grief and despair I saw a mother dove exhibit when a gopher snake devoured her fledglings. She remained on the ground underneath the nest for hours, looking forlornly up. The next day I saw her sitting on the empty nest. You will never convince me she was not feeling emotional pain.

I keep forgetting that anthropomorphism is still an accepted principle of scientific thought--something to be shunned lest you not be thought a serious scientist. I have a lot of scientist friends, and imagine that most of them still have this dogmatic view of anthropomorphism. But it’s also true that attitudes have been changing for quite a while, and many very respectable scientists now accept at least the possibility that animals have feelings too. Certainly not feelings exactly like human feelings, because they sense the world in different ways, but feelings nevertheless. Franklin D. McMillan, a brilliant veterinarian, has written about this topic in his book Unlocking the Animal Mind. Dr. McMillan points out that it doesn’t make sense that emotions suddenly emerged full-blown in human beings, without first having evolved in other animals.  

This lovely photo is used with permission of the photographer, Sharon Elizabeth Yocum
Anyway, back to the hawks. They continued to soar above us as our discussion went on. As their beautiful streamlined bodies flashed in the sunlight, I imagined them having breakfast together, then one of them communicating something like, “It’s such a beautiful day, let’s go for a soar!” And so they did, their seeming joy in this beautiful spring desert day mirroring the joy of the four humans on the ground watching them.

Monday, April 20, 2015

Cactus Color Wheel

April is a great month in the Sonoran Desert because wildflowers and trees are still blooming and the cactus have begun to chime in with their gorgeous, waxy flowers. The flowers pictured here are mostly from the staghorn cholla, Cylindropuntia versicolor. "Versicolor" refers to the fact that each plant has a different color flower. Most are in various shades of red, orange, and pink. The last flower in the series is from a different but related cactus, which I believe is cane cholla. I took all of these photos on a walk on desert trails in Tohono Chul Park.

Saturday, April 04, 2015

Palo Verde Glory

This is the best time of year in the Sonoran Desert: Spring, lasting from sometime in February to usually the end of April or even into May. We looked at some wildflowers in the previous post, and I'll post pictures of cactus blooms soon, but today I want to highlight the amazing and startling palo verde blossoming, which has just begun and will last another couple of weeks.

Everywhere you go in town and out of it, particularly in the foothills, you will be awed by the brilliant displays of palo verdes in bloom.

These gorgeous trees were flowering alongside the Rillito River
There are two main types of palo verdes--the Blue Palo Verde, which blooms first, and the Foothills Palo Verde, which blooms a week or so later. The Blue blossoms are a deeper yellow color, like the filling in a lemon pie. The Foothills is paler, more like lemon pie with meringue. The difference is caused by the fact that the petals on a Blue Palo Verde are all yellow, while the Foothills tree has one white petal on each flower.

Blue Palo Verde Blossom
Foothills Palo Verde Blossom
This beautiful Blue Palo Verde greets visitors in the central part of Tohono Chul Park:

 Whenever I'm driving around, my heart feels as if it has stopped when I come upon one of the thousands of our glorious palo verdes and its magnificent blossoms. I'll leave you with a long shot and closeup of this stunning tree that I saw a couple of years ago in a medical plaza.


Wednesday, March 25, 2015

Sonoran Spring Beauty

This time of year is breathtaking throughout the Tucson area. Hiking in a desert canyon can be like stepping into a medieval millefleurs tapestry. Our yards and medians have erupted in color. Courting and nesting birds are everywhere, as are butterflies of all sizes. Please join me for a brief walk in Tohono Chul Park for a small taste of what I see every day.
One of the new entry paths into the Park, lined with Parry's penstemon
Brittle bush grows in profusion everywhere, on easements, in washes, in yards, and throughout the Park
Penstemons appear to be growing from this ocotillo, which will send out its own blooms any day now
Gorgeosity in the Sundial Plaza, along with a scrap-metal vulture
Blackfoot daisies line several paths
Hedgehogs are the first cacti to bloom; these are Boyce-Thompson variety
These lovely flowers are new to me this year: Baby's Bonnet
On the way out of the Park, let's stop for a close look at these beautiful tufted evening primroses
But wait! There's more! Here's a look at late spring from last year, with a different cast but just as much beauty.