Wednesday, August 8, 2012

I have lapped filthy water from a hoof print

"I have lapped filthy water from a hoof print and was glad to have it."
"If I ever meet one of you Texas waddies who says he had never drank water out of a horse track I think I'll shake his hand, give him a Daniel Webster cigar."
In Charles Portis' True Grit the Texas Ranger LaBoeuf tries (and fails) to impress U.S. marshall Rooster Cogburn.

Couch's Spadefoot, Scaphiopus couchii
 In the real West in Arizona, the filthy water of a hoof print could well be your amniotic fluid, cradle, bathwater, and hunting ground -- if you are a young Couch's Spadefoot.  

Land-under in the bajada of the Tucson Mountains (our backyard)
On July 29th a huge thunderstorm rolled over our land and brought nearly three inches of rain in one hour. It poured down so hard that most of the water just raced down hill, carving out old arroyos, piling up new sand dunes, and slicing through flat areas to form new washes. For a couple of hours the sound of rushing water swallowed everything else.

Calling male Couch's Spadefoot by Seth Patterson
As soon as that din calmed down, a faint bleating like from a herd of sheep lost in the dark could be heard. The mating concert of Couch's Spadefoots.  

Mating spadefoots by Manuel Nevarez
 Spadefoots are also called toad-like frogs (Pelobatidae). While their shape is toad-like (short-legged, squat, with a bluntly rounded snout) their skin is smooth like a frogs and they lack the obvious paratoid glands of the Bufonids (most of our toads). But their vertical pupils and the spade-like tubercle on the underside of each hind foot set them apart from both frogs and toads. If you set a spadefoot on loose substrate you can watch how quickly he disappears backwards by shuffling those hind feet. These amphibians hold endurance records: they can stay under ground for years during droughts, nearly dried up and motionless in a little chamber plastered with their own skin excretions.

Spadefoot tadpoles Photo by Jeff Mitton
 Drumming raindrops of a substantial monsoon storm get the Spadefoots up and ready to find temporary rain pools to mate and lay their eggs. Tadpoles can be found a day later, feeding on organic debris and quickly developing algae.

The surface of the desert soil is reshaped by the heavy hoofs of horses.
Today, on the 8th of August, all rain pools have disappeared. But every morning, depressions in the soil are still visibly moist.

A tiny youngster in a hoof print
Walking our dogs around sunrise, we found tiny spadefoots emerging from those muddy spots,  scrambling for cover under freshly green Triangular-leaf Burr Sage bushes. Most of the deeper mud spots were the hoof prints of our neighbors' rodeo horses.



The little amphibians are still smaller than grasshoppers, not much more than a quarter inch. They are able to absorb moisture through their skin, but they have to leave the exposed muddy tracks before the morning sun reaches them.


Some will try to risk the heat of the day in the cracks that open up as the mud in the hoof impression dries. I hope they make it!


Young Red-spotted Toad (Bufo punctatus)?
When I went through this morning's photos, I realized that some of the larger anuran kids seemed to have horizontal pupils and looked rather toad-like. These are young Red-spotted Toads.

Adult Red-spotted Toad (Bufo punctatus)
They supposedly need more permanent creeks and pools for breeding, but the adults are around, and those rainwater pools are all our desert here has to offer. I may  have even heard their monotonously trilling mating call and mistaken it for the purring of some of the local Night Hawks.

8 comments:

  1. This is incredible!!! I learn so much from your work and observations. I began paying attention to the bugs like you do. And I remember our talk about when it warms up, the bugs come out. So I've paid attention to the bugs and have really enjoyed the experience. Now these toads! I didn't even know they lived here. Thank you for taking the time to share your pics and knowledge. This would be an exciting find for me.

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  2. I don't know which are cuter, the tiny toadies, or those pudgy leg-sprouting taddies!

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  3. Have you ever noticed the vegetation there in your backyard has a much greener richer colouration than at Spring time after winter's rains ? That's why I love monsoon season. It's absolutely amazing how those little desert toads are everywhere in the deserts southwest even in places so monnscape looking void of even desert plant vegetation that you'd never guess.

    Perfect pictures illustrating lifecycle. The tiny Toads reminded me of the season around here in Sweden where we had so many you could hardly walk on the forest pathways. They may not have frogs here but they do have toads.


    Strange year for Scandinavia. No summer and zero growth in garden and wild for fruits & berries of all kinds. Some friends from Norway said that if there is another year like this the region will be in trouble food prices and availablity wise. But I see your area there isn't fairing much better.

    -

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  4. The only good result would be if the now super-rich Norway would decide to finally join the European Common Market and the Euro. Fat chance. They always feared any competition for their homegrown apples.

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  5. So fascinating!! Thank you, I always enjoy your wonderful posts and learn so much!!

    *When I saw the title of your post I immediately thought of the scene in 'True Grit' :)))

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  6. Great stuff! Two days later we actually got a lot of monsoonal rain in SoCal, including at our house (although Gary and I were in Minnesota that day). Must have been some mass of moisture around at that time.

    We also saw a huge pool in Payson, with shrimp, and huge Hydrophilus beetle larvae, as well as toad tadpoles. Maybe from the same system?

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  7. *sigh*
    teeny, tiny toads and frogs make my heart all soft and sappy.

    SO CUTE!! SO VULNERABLE! SO dang brave (tho' they have little choice). And so tinsy.

    Adorable. =) Thanks so much. My coworkers have done many a salamander and frog survey where the habitat (or potentially suitable habitat) is a cow hoof imprint, or a tire rut. Craziness .

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  8. Found this doing a search on the LeBeouf quote about water from the hoof print. One of many classics in that fantastic remake. I must disagree with the classification of the Couch's Spadefoot as a toad-like frog (Pelobatidae) based on its "smooth skin". The top picture, if representative of most of these Couch's, doesn't appear to have very smooth skin, while the mating pair a few photos down certainly doesn't. Very nice article and excellent photos other than that small nit pick. Thanks for doing it!

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