JIM CONRAD'S
NATURALIST NEWSLETTER
Issued from Rancho Regenesis
in the woods near Ek Balam Ruins north of Valladolid in
Yucatán, MÉXICO

April 30, 2017

*****

TOAD ORGY
Last week one afternoon our critically hot, dry, late-dry-season weather was interrupted by a much appreciated 3mm shower (1/8th inch), and the next afternoon by a 4mm one. The morning after the second shower, the little cement-lined pond near the new well abounded with mating Gulf Coast Toads, a few of which are seen at http://www.backyardnature.net/n/17/170430te.jpg

Some bored-looking orgy participants up close are pictured at http://www.backyardnature.net/n/17/170430tf.jpg

A single mating couple are seen at http://www.backyardnature.net/n/17/170430td.jpg

The above pictures show females with smaller males on their backs, in the frog/toad reproduction process known as "amplexus." Male frogs and toads don't bear penises, so during aplexus the male rides atop the female grasping her trunk with his forelimbs, and when the female eventually discharges eggs, usually into the water, the male sheds his sperm over the eggs. It's "external fertilization." You might enjoy viewing one of my most frequented pages on the Internet, a nicely photographed one detailing several surprising features of amplexus, available at http://www.backyardnature.net/frogsex.htm

Besides males in this species being considerably smaller than females, you might also notice the striking color differences not only between males and females but also between individuals of the same sex. In the past this has caused confusion with identification, so I'm glad to see at last just how much variation there is.

*****

NICE BRONZED COWBIRD PICTURE
At http://www.backyardnature.net/mexnat/cowbird.htm, on our Bronzed Cowbird page, we've already looked at these strange-behaving, red-eyed nest-parasites. However, one morning this week a small flock winged into the rancho, resulting in a better picture than any previous ones I've managed. You can see a male with his neck feathers fluffed out, attended by a female who apparently finds it alluring, at http://www.backyardnature.net/n/17/170430cb.jpg

*****

SNAKE BENEATH CARDBOARD MULCH
During the hot dry season it makes sense to mulch around plants, to keep soil water from evaporating. At the rancho, any herbage that could be converted to mulch is fed to the livestock, so I look to other sources. I've used cloth from a torn-up tent and plastic sheets, but mostly for mulch I've spread flattened cardboard boxes onto the ground. The results have been striking: Mulched plants nearly always do much better than those without mulch. During the rainy season, though, I'll just have to see whether mulch helps, hinders or does nothing for plant growth.

In arid conditions, when I broadcast-sow small seeds that end up buried close to the soil's surface, I also cover the newly sown ground with cardboard, after first watering the soil. In a single day unprotected, crumbly soil can dry out so completely that germinating seeds near the soil's surface can be killed by desiccation. A cardboard cover shades the soil and drastically slows the drying-out process. You just have to check each morning when seeds might be sprouting, because if sprouts emerge in darkness below the cardboard, they'll grow long and spindly, then when finally they're exposed to sunlight quickly they'll be killed by the harsh conditions.

All that said, one morning this week I lifted up a sheet of cardboard protecting recently sowed collard seedlings, and found the little foot-long snake shown at http://www.backyardnature.net/n/17/170430no.jpg

A close-up of the head highlighting the species' distinctive scale pattern, as well as offering a study of its beautiful coloring, is at http://www.backyardnature.net/n/17/170430nn.jpg

We've run into this completely harmless, too-small-to-bite species several times, so its tendency to bluff a dangerous look by raising and flattening the front of its body like a cobra, and to "faint" when disturbed, is well documented with pictures on our page for the species at http://www.backyardnature.net/yucatan/ninia-rd.htm

On that page we use the English name Red Coffee-Snake, but over the years I've gravitated to using its much more appropriate-seeming Spanish name Basurera, because that name more or less means "hanging about in rubbish." And it's true that I've always found this snake in disturbed areas with junk, garbage or, in the present case, beneath cardboard, but I've never seen it in any context associated with coffee.

*****

CAESALPINIA'S EXPLODING LEGUMES
At http://www.backyardnature.net/yucatan/caesgaum.htm we look at a yellow-flowering tree member of the Bean Family endemic to this part of the world and common in this area, a species I call Yucatan Caesalpinia, though it doesn't really have an English name. Several grow around the hut and nowadays they're attracting attention in an unexpected way. You can see part of a tree in the current condition, its branches leafless for the dry season but bearing large numbers of short legumes, at http://www.backyardnature.net/n/17/170430cy.jpg

The legumes are explosive. Here at the end of the dry season they are crispy dry and, especially in mid afternoon when the sun beats down the hardest, they are designed so that their two sides pull against one another until finally something snaps, the sides fly apart, and beans are thrown everywhere -- seed dispersal through legume detonation. A couple of unexploded legumes are shown at http://www.backyardnature.net/n/17/170430cz.jpg

An open legume displaying its beans is at http://www.backyardnature.net/n/17/170430cx.jpg

The snapping legumes can be heard from 20 feet and more away. Most of the day there are no snaps, but in mid afternoon when the sun shines brightest you might hear them every ten or fifteen seconds, so it's quite a performance. Our afternoons are partly cloudy, so part of the show is that the very moment a cloud covers the sun the snapping ceases instantly,but when the sun returns, so does the snapping.

Interestingly, a second tree at the ranch also produces snapping legumes, and it's also a member of the genus Caesalpinia, though it's not native to this area. That's the Dwarf Poinciana, Caesalpinia pulcherrima, much planted in the tropics worldwide because of its beautiful flowers. You might be interested in comparing the two species' blossoms -- in seeing two variations on the Caesalpinia theme. The Yucatan Caesalpinia's flowers appear at http://www.backyardnature.net/yucatan/caesgaum.htm

The Dwarf Poinciana's flowers are shown at http://www.backyardnature.net/yucatan/d-poinci.htm

*****

DUTCHMAN'S-PIPE FRUIT WITH LEAVES
Last week we looked at a Dutchman's-Pipe vine's fruits, shown on our page at http://www.backyardnature.net/mexnat/aristolo.htm

At that time we reckoned the name of the vine to be Aristolochia maxima, but it was a little awkward making the identification based only on fruits. This week another vine was found bearing both fruits and leaves, shown at http://www.backyardnature.net/n/17/170430as.jpg

Now with greater confidence I can call our local Dutchman's Pipes Aristolochia maxima.

This is a good example of how it goes when identifying plants here in the Yucatan, when all you have is the Internet to help you. In contrast to the situation in North America and Europe, often species native to this are are not well illustrated on the Internet, and images that can be found often are misidentified. In fact, in a Google image search on "Aristolochia maxima fruits," at least using the Mexican Google at this time, the first pictures that turn up show plants with leaves very unlike ours. Those images were posted by amateur gardeners, however. Only when herbarium specimens posted on university-affiliated sites are checked are leaves seen matching those in our pictures.

Each year the Internet-using identification process becomes easier, as more experts post pictures and technical literature online. Here in the Yucatan the most important Internet source is that provided in Spanish by CICY, the Center for Scientific Investigation of the Yucatan, in Mérida, online at http://www.cicy.mx/sitios/flora%20digital/indice_busqueda.php

*****

TOO MANY TOADS
A quick glance at the little pond was enough to see that too many toads were gathered there. Especially now during this late dry season when relatively little toad food is available, in a flash it was clear that in and around the pool there just couldn't be enough food for them all. Still, the pond's entire surface was rippled by ardent toads with one notion on their minds: To mate, and create untold numbers of new toads.

On the morning when a Green Heron turned up stalking along the pond's banks, I was glad not only to see a bird not usually occurring here in the arid interior, but also because I figured that the bird might help with the toads' overpopulation problem. Whatever tadpoles or young toads the heron might catch would relieve, just a little, the pending starvation and disease Nature would have to employ to bring the area's toad numbers back within bounds.

Thinking like that led to comparing the toad pond situation with that of humanity's on our little Earth. It's the same dynamic: Too many beings with too much appetite for the limited resources at hand.

Predation, starvation and disease... These are Nature's tools for keeping numbers in line for living beings other than humans. With humans, there's another option: That of using our minds.

But, our human minds can tilt in two directions. First, they can tilt toward telling us that we need to voluntarily regulate our numbers and appetites, and thus avoid inviting Nature to deploy starvation and disease. Second, our minds can tilt into lethal mental states in which it seems OK, even desirable, to conduct wars, genocides, and to turn a blind eye to those needing our help to survive.

The more I hear of the world's daily news, the more it seems that the art of being human largely consists of choosing which way we let our minds tilt.

*****

Best wishes to all Newsletter readers,

Jim

All previous Newsletters are archived at http://www.backyardnature.net/n/.