Wednesday, May 11, 2016

Docent Diaries - An Update from the Desert Museum

Tucson, Arizona

After a busy winter season, things are beginning to slow down at the Desert Museum.The heat is ramping up, getting ready for summer's blast. Out-of-town visitors find somewhere cooler to go.  Afternoon tours are eliminated. Winter visitors are leaving town. The docent corps, too, is thinning out.  But, for those of us who brave the warmer temps, things are always exciting at the Museum.

Our Cactus Garden has undergone a transformation in recent months and is now a stunning showcase for all things spiny.  Friday docents give a tour every week of the garden, and visitors are fascinated by the shapes, colors and adaptations of cactus from the Sonoran Desert as well as more tropical locales farther south.  I love giving these tours and last Friday I had six enthusiastic visitors learning about what is, and what is not, a cactus.

The cactus blooms were sort of in a lull, but there was this lovely, mounding Notocactus.


And this Mexican night-blooming cereus, which was just starting to close after its nighttime shift. Interestingly, the one in my garden bloomed the same night, for the first time ever.

Mexican Night-Blooming Cereus

Not to forget our amazing saguaro cacti that are still blooming full blast.

Friday is a popular day for school groups to visit the Museum.  A good thing or a bad thing, depending on your point of view.  As a docent, I love having the schoolkids come out, and I am especially  happy when they are well-chaperoned and have been given learning assignments.  After the Cactus Garden Tour, I was stationed in the Ethnobotany Garden and I had a group of high school girls who listened intently and asked great questions.  First, I had to explain what ethnobotany is! Just a big word for how people use plants.  They loved tasting the mesquite flower, and feeling the texture of the jojoba oil.

Near the People and Pollinators Garden is the Maze Garden where I found a gorgeous Desert Willow (Chilopsis linearis) covered in deep magenta flowers. This is not a true willow, but a member of the Bignonia family.  Large, fragrant, orchid-like flowers cover the plants from April to August in a range of colors from white to this fuchsia color.

But my real mission was now down the path in the Big Horn Sheep area, where not one, but two, lambs have recently been born.  There's no doubt that all babies are adorable, but these lambs take the cuteness factor to a whole new level.  Within just days of birth they are scrambling up the steep cliff of the enclosure, bouncing and leaping all over.

The two ewes are mother and daughter.  The lambs, one a ram and one a ewe, were born one month apart, first to the mother and then to the daughter. Playtime is followed by a crash - moms and babies find a spot in the shade to get some rest. Along with the visitors, I could watch these guys all day! We'll have the pleasure of watching them for another 8 months or so before the lambs are shipped off to another facility.

Time for lunch and our monthly potluck.  There's always so many fun dishes to try, and oh! the desserts! This was a special one as we were honoring our day captains at the end of their tenure.  Each docent day has two captains that serve for one or two years, doing the scheduling and keeping us docents in line.  Sort of like herding cats.  We are thankful that they are willing to do the job, which can be stressful and frustrating.  I know.  I've been there!

Martha, Rae, Carole, Marsie
Outgoing captains Rae and Marsie, with incoming captain Martha, and me

Animal handling is one of the great privileges and rewards of being a docent.  Each year we choose the categories of animals we want to handle, and then go through training and certification on each.  This year, my animals are snakes and middleweight raptors.  Everybody loves the big birds, of course.  But the snakes, not so much.  So, it's especially important to educate visitors about snakes, and perhaps change their thinking a bit.  On this day, I had a large common kingsnake.  It's amazing how many people's first question is, "Is it poisonous?"  Right.  I'd be fool enough to stand here holding a venomous snake.  Kingsnakes, which are constrictors, prey on a variety of small animals, including other snakes.  Famously, even rattlesnakes are on their diet.  Which leads people to classify kingsnakes as 'good' snakes.  I gently inform them that there's no such thing as 'good' or 'bad' snakes. All snakes are just trying to make a living, using the tools they've been given.

There were still many more sights to see as the day went on.  Passing a very large saguaro, I could hear baby birds calling.  Just then this male Gila woodpecker poked his head out of the nest.

It is the male woodpecker who does the work of excavating the hole in preparation for nesting, and then he shares the duties of caring for the nestlings.  Right after I snapped this photo, off he went, most likely in search of more food for those ravenous babies.

Baby animals are everywhere on the grounds.  Black-tailed prairie dog pups have emerged from their burrows and are providing a never-ending source of entertainment.

One lucky pup was getting a serious grooming from mom.

Last stop of the day was in front of the mountain lion exhibit.  Our young male, Cruz, was feeling frisky.

Big Stretch
And then, he decided to talk to us.


Have you ever heard a mountain lion meow like a housecat?  Well they do, and it sounds so odd coming from this big cat.  Mountain lions are the largest of the small cats - those that meow and purr.  The big cats roar.

That was a perfect ending to a most excellent day!

Sunday, May 1, 2016

Gila Monster - A Visit from an old Friend

What's black and orange and beaded all over? Why, a big, fat, venomous lizard, that's what!

The Legendary Gila Monster, that almost mythical creature of the Wild West, about whom tall tales are told, about whom superstition and myths abound. And yet, here he is, right in my back yard.  I consider myself among the lucky ones who have actually seen a Gila monster in the wild.  Some people live their entire lives in the Sonoran Desert and never encounter this fascinating creature.  

Even the name, 'monster', is absurd and reflects the amount of misinformation and exaggeration about a lizard that is barely two-feet long, slow and lumbering, shy and non-aggressive.  Perhaps it's the elusive nature of a creature that spends 90% or more of its life underground, hidden from view, and about which, as a result, not a lot is known. 

The Gila monster is one of only two venomous lizards in North America, and the only one in the U.S. The other, the Mexican beaded lizard, lives exclusively south of our border, in Mexico and into Guatemala.  Gila monsters are known as nest raiders, and since they prey almost exclusively on food that will not run away from them - baby rabbits, bird eggs, baby lizards - their venom is not needed to subdue prey as is the venom of rattlesnakes, for instance.  So, what's the purpose of the venom? Defensive?  It seems the most logical.  The venom gland is located in the lower jaw, and travels through the grooved lower teeth to enter the victim, producing excruciating pain.  Just in case you were thinking of getting away after being bitten, the Gila monster's other trick is to not let go, continuing to gnaw, increasing the venom delivery and making sure you are plenty sorry you harassed him.  Not to worry, however, you won't die from the venom.  And that's the good news.  The bad news is that you'll probably wish you would!

The beautiful black and orange/pink beaded pattern is unique to each individual lizard.  The genus name, Heloderma, means studded skin. The 'beads' are actually bony scales, making the lizard's skin extremely difficult to penetrate and providing a good defense against large predators such as coyotes. Two subspecies differ in the beading patterns - banded, with regular, well-defined bands all over; and reticulated, with the irregular pattern such as the one shown in the photo.  The reticulated is the species of southern Arizona and the only one I've ever seen.   Oddly enough, all newly hatched Gila monsters are banded, but the ones in our range (Heloderma suspectum suspectum) develop the reticulated pattern as they mature. The small western banded gecko is sometimes mistaken for a baby Gila monster.  

A forked tongue, like that of snakes, gives the Gila monster an extremely good sense of smell, and allows it to locate even buried eggs.  Emerging from the winter den in spring, the Gila monster goes looking for food, and may gorge itself when food is available, storing fat in the tail for the long, lean months ahead.  A mate is also on the agenda, and, if that quest is successful, the female lays eggs in July or August, burying them in the sand.  The eggs overwinter and hatch in the spring.  

In recent years, research on Gila monster venom has led to the development of exenatide, a drug that is a synthetic form of a substance found in Gila monster saliva, for the treatment of Type II diabetes. It helps control blood sugar levels and leads to weight loss. 

Many years ago, we named a visiting Gila monster Albert.  Since then, every one who comes to our yard is known as Albert.  I suppose it would be possible to compare photos and see if Albert is one individual or many different ones.  I prefer the mystery.  See you again next year, Albert.

The End