January 3, 2016

RUBY-THROATED HUMMINGBIRDS OVERWINTERING HERE
By placing leg bands bearing unique numbers on a large number of Ruby-throated Hummingbirds, it's been shown that in the spring up north often specific individual birds arrive at the same feeder on the same day for years in a row. Some folks get attached to their hummers, so they might be gratified to know that this winter the Yucatan is buzzing with Ruby-throats just waiting until they can return back north. One morning this week one that seemed especially interested in this human sat on a branch nearby watching me and preening his feathers in the early morning sun, shown at https://www.backyardnature.net/n/16/160103hu.jpg.

Here at Hacienda Chichen in the north-central Yucatan Peninsula we can look for these hummingbird species: Canivet's Emerald; White-billed Emerald; Buff-bellied; Cinnamon; the Ruby-throated Hummingbird, and other species who come up sporadically from the south. So, with immature and winter plumages involved, how can we be sure this is a Ruby-throated? Several species display immature and female plumages very similar to our bird's, especially those of the Black-chinned Hummingbird.

Mainly, the species most likely to be confused with Ruby-throats don't occur in the Yucatan. Also, our hummer's beak is notably shorter and straighter than in many species, and it's black, not red. The white spot behind the eye -- the "postocular spot" -- is right for a female or juvenile bird, plus Howell writes that the immature male Ruby-throat bears lines of dusky flecks on the throat, and they are very conspicuous on this individual.

In the US Deep South often individual Ruby-throats remain in the area late in the season, and even surve freezing temperatures. If Ruby-throats are that good at dealing with the cold, why don't more remain up north instead of making the dangerous flight to down here? One small population does permanently winter in the Outer Banks of North Carolina. The experts at Hummingbirds.net explains that all hummingbirds are carnivores -- nectar is just the fuel they use to power their flycatching activities -- and that they depend on insects that are not abundant in subfreezing weather. Most hummers must migrate south to "home" in the American tropics, or risk starvation.

At http://www.hummingbirds.net/migration.html you can read lots of interesting details about Ruby-throat migration. Another point made there is that during spring migration some birds may follow the Gulf Coast northward on a longer but safer route to North America, but many who overwinter between southern Mexico and Panama take a straighter route through the Yucatan, gather on the northern coast gorging on insects and spiders to build up fat, and, when the weather seems to be OK, usually at dusk, launch northward into the open sky, nonstop, for up to 500 miles, taking 18-22 hours, depending on the weather.

When you're on the northern coast seeing how tiny these birds are, and how vast and imposing the sky out over the Gulf toward the north usually looks at dusk, you just have to be amazed.

*****

HUMMINGBIRD NEST
This week in a Mamey tree a hummingbird nest turned up typically constructed of spiderwebs and flakes of foliose lichen, as you can see nestled among the Mamey's long, slender leaf petioles at https://www.backyardnature.net/n/16/160103ho.jpg.

A view from above the nest shows it empty of eggs, but with what looks like bits of shattered eggshell in the bottom, at https://www.backyardnature.net/n/16/160103hn.jpg.

I asked the Maya workers, who seldom overlook such things, if they'd noticed a hummingbird hanging around that part of the tree and, yes, some time ago there was a tiny, greenish one zipping all over the place, but that description doesn't help much in figuring out which species it was.

Maybe the nest will be reused and, if so, we'll be watching to determine the species.

*****

PLANTHOPPER NYMPH WITH AN OUTLANDISH TUFT
In the next section a pretty herb known as Ruby Leaf is introduced. While a Ruby Leaf flowering head was being photographed, an item I'd thought to be a random piece of detached plant fuzz shifted to the stem's other side, as if it were a living thing. Swiveling the camera into position, the tiny critter turned out to bear at the tip of his abdomen a tuft of hairs longer than the body itself, shown at https://www.backyardnature.net/n/16/160103ph.jpg.

With volunteer insect identifier Bea in Ontario on vacation, I figured that for me IDing such a tiny, strange creature would be hard, maybe impossible but anyway I sat about "doing the bug" the way I usually "do the botany."

First of all, what's in the picture has to be recognized as an immature stage of an insect that undergoes incomplete metamorphosis -- where what emerges from the egg looks like a small version of the adult, but with undeveloped wings and sexual parts. Such immature stages are called nymphs.

So, which of the 25 to 35 insect orders would this nymph belong to? The saddle-like covering wrapping over the back, and the bulging compound eyes on a blunt head, look grasshoppery to me, and grasshoppers belong to the order Orthoptera, so with that idea, on the Internet, a Google image-search was made on the keywords "Orthoptera nymphs."

After reviewing numerous pages of thumbnail pictures, finally something green and grasshoppery with something white sprouting from the end turned up. However, it was a planthopper nymph, and planthoppers belong the order Hemiptera, not the grasshopper's Orthoptera. Having made such an elemental mistake about the order, finding this picture was pure luck.

Up in Mississippi we've looked at an adult planthopper before, shown at https://www.backyardnature.net/n/a/flatid.htm.

Planthoppers are commonly encountered, smallish, often greenish or brownish insects who suck plant juices through straw-like proboscises, and sometimes hop amazing distances for such tiny creatures. They constitute a subgroup of order Hemiptera -- an "infraorder" known as the Fulgaromorpha -- of which over 12,500 species are described worldwide, with more being discovered regularly. Now it was time to do an image search on "Fulgaromorpha nymphs," and that was an eye-opening experience.

For, Fulgaromorpha nymphs, or "fulgoroids, " bear a bewildering variety of tufts and filaments on their rear ends, the arrangement depending on the species. Sometimes filaments coil about, sometimes they flair in all directions, or bend upwards or to the side, some are feathery... on and on the variations come, and if you keep browsing pages of thumbnails of Fulgaromorpha numphs, eventually you see an individual having them sticking straight out just like ours.

Based on the overall anatomy, and the tuft of straight, white filaments at the abdomen's tip, it can be said that our little nymph belongs to the family Issidae, a family occurring throughout the Northern Hemisphere, and consisting of about 1000 species in ±215 genera. And that's as far as I can go toward providing a name.

We can say that what's in the picture is an "Issid nymph," Issid being the name applied to a species in the family Issidae. In North America, Issids occur mainly in the southern states, with 18 species listed for Texas, ten for Arizona, and with states like New York and Idaho having only one, and all of New England and the upper Midwest having none.

Not much is known about Issids, other than that they suck plant juices, can perform mighty hops but generally walk across a plant's surface slowly. One reason for the lack of information is that Issidsy don't occur in large numbers so are not an agricultural threat, and thus few people study them.

With regard to the white items at the tip of the Issid nymph's abdomen, they're called abdominal filaments, and the literature describes them as wax secretions. The filaments sure don't look as if they're made of wax, but at such a small scale the laws of physics are different, so wax might behave in surprising ways. In many planthopper species wax secretions serve to camouflage the insect. Maybe my first impression -- that our Issid nymph was an errant wad of plant fuzz -- was the exact impression the nymph "wanted" to convey to predators.

*****

RUBY LEAF
I don't recall seeing three years ago when I was staying at Hacienda Chichen the purple-leafed plant shown adorning the base of a big Piich tree at the edge of the garden at https://www.backyardnature.net/n/16/160103an.jpg.

That plant is all over the place now, both planted and going wild. In the picture, notice that many of the plants arise inside a long planter, barely visible at the picture's lower, left corner, but many other plants have rooted outside the planter and are doing just as well as those inside it. This is definitely a plant capable of becoming invasive.

Still, it makes such a pretty show that when some turned up at the forest edge, apparently having been dumped there by the gardeners, I salvaged and transplanted them into a tin can, until they could recuperate enough to be planted next to the hut. A closer view of a single plant is shown at https://www.backyardnature.net/n/16/160103al.jpg.

At first I thought this was an escaped, white- and smaller-flowered form of the Globe Amaranth, which you can compare at https://www.backyardnature.net/yucatan/globe-am.htm.

However, notice that the spherical heads of Globe Amaranths produce leaves immediately below their heads, while our plants' spherical heads are set atop long, leafless stems, or peduncles. Botanically, that's a big deal, throwing our plants into an entirely different genus. However, with those white, stiff "bracts" forming the spherical heads, with tiny, hard-to-see flowers down among the bracts, they're clearly in the same family as Globe Amaranths, the Amaranth Family, the Amaranthaceae. A close-up of our tin-can plant's head showing not a hint of leaves below the head, is at https://www.backyardnature.net/n/16/160103am.jpg.

Finally I remembered that here at the Hacienda back in 2010 I found an Amaranth Family member without leaves below their white heads, growing on the wall of the old church, as shown at https://www.backyardnature.net/yucatan/joyweed.htm.

That's a member of the genus Alternanthera, species of which often are called joyweeds. The church-wall plants and our tin-can one are so similar that now the question becomes, is our tin-can plant just a purple-leafed form of the church-wall one, or is it a different species of Alternanthera?

It turns out that it's a different species, ALTERNANTHERA BRASILIANA, known by many English names, the most common one seen in print being Brazilian Joyweed. That name is misleading, though, because the species is native from Brazil north through northern South America and Central America, to Mexico and the Caribbean. Among its other names are Metal Weed, Parrotleaf, Joseph's Coat, Calico Plant, Ruby Calico and Ruby Leaf, the latter appealing to me most. That name causes me to wonder if maybe the name joyweed derives from rubies being jewels, and Spanish for jewel being joya.

Ruby Leaf has become an invasive in Florida, so it's found in the US and thus described in the online Flora of North America. In that detailed description there's no mention of its leaves being purplish. However, gardeners favor the species, especially as a hedging plant, so several cultivars with various degrees of purplish leaves have been developed. Maybe ours is an escaped cultivar -- or possibly it's a natural purplish form from which the purplish cultivars have been developed. I don't find green-leafed forms here, though plants growing in deep shade tend to be more green than purple, as do freshly emerging leaves.

Ruby Leaf is busy escaping into the wild in much of the world's tropics. In Australia it's regarded as a weed causing environmental impacts, particularly along waterways in warmer and wetter coastal areas.

*****

RED SOILS, VOLCANOES & DESERTS
One of the pleasures of being at Hacienda Chichen is that sometimes very interesting visitors pass through. That was the case last week when a couple of scientists on sabbatical from the University of California at Riverside, and a friend, walked up to the hut one evening as I was snipping whiskers with a lady's compact mirror held before my face. The scientists had conducted soil and plant community studies at El Eden, a reserve 40 kms west of Cancún.

That evening with the half moon above us I learned a lot about the Yucatan's red soil. Geologically, the Yucatan is a massive block of limestone, so up to now I've assumed that the Yucatan's red soil was more or less equivalent to red soils I know very well, also developed atop limestone, in the US Southeast. The short story for the northern red soil is that as the limestone dissolves it leaves behind traces of iron, which oxidize, and oxidized iron -- often known as rust -- is reddish.

The Yucatan's red soil has a more complex history. Before getting into that, though, you might like to review our 2012 piece on "The Yucatan's Red & Black Soils" at https://www.backyardnature.net/yucatan/soil.htm.

I've long suspected that the Yucatan's red soil had something peculiar about it because often you see Maya cornfields, or milpas, on very thin red soil, often with white limestone poking through here and there, and the crops seem to be growing fairly well there. Up north in such thin, red soil atop limestone you don't bother trying to grow things, because it's just too "poor" -- too few nutrients for plants to thrive and not enough organic matter to hold water.

My guests' preliminary studies at El Eden seem to suggest that the secret ingredient of the Yucatan's red soil is volcanic ash. Not just ash deposited during the last few centuries, but during the last few millions of years, when the limestone or precursor to limestone beneath our red soil was forming at the bottom of a shallow sea, occasionally being augmented with significant wind-deposited volcanic ash. That's important, because volcanic ash carries minerals such as phosphorus and magnesium, which are critically important to plant growth. Today, as the limestone dissolves below the Yucatan's thin soil, it leaves behind not only iron that reddens the soil, but also plant nutrients that help green the landscape with healthy, luxuriant growth.

On the Internet several papers document not only the contribution that millions of years of volcanic ash have made to the Yucatan's soil, but also the enriching effects of Saharan dust -- dust carried here on winds blowing from northern Africa's Sahara Desert, across the Atlantic, to the Caribbean/Yucatan region. A 2012 article by R. Das and others, abstracted at The Smithsonian/NASA Astrophysics Data System website, entitled "Saharan dust in Yucatan soils: Sr isotope and trace element evidence of dust inputs," documented that:

By "calcareous substrate" is meant "limestone."

The researchers found evidence of Saharan dust on the Yucatan's red soil, but couldn't determine how important it was relative to other inputs, such as the limestone bedrock dissolving, and volcanic ash being deposited.

My curiosity aroused by the visitors from Riverside, the next morning on a bike trip to Pisté to buy bananas, I paid special attention to the fresh roadcuts made by the recent highway widening. A hard-to-interpret formation with white limestone seeming to finger up through red stuff above it is shown at https://www.backyardnature.net/n/16/160103dt.jpg.

That mystery resolved itself when I went up to the formation and scratched the wall with my fingernails. The whole roadcut was composed of white limestone, just that red dirt from above had washed down over the entire face. Machinery had streaked the face with vertical scars exposing white limestone. The fingernail scratching test often is a good one in the field.

At another place, bands of white limestone appeared with what seemed genuinely red-hued limestone, which one could easily imagine contained ancient volcanic ash or Saharan dust, shown at https://www.backyardnature.net/n/16/160103du.jpg.

A close-up of one reddish layer is shown at https://www.backyardnature.net/n/16/160103dv.jpg.

Wind-deposited volcanic ash and Saharan dust well may have bestowed the Yucatan's red soil with a fairly unending supply of nutrients absolutely necessary for agriculture, but also at least some researchers think that volcanic eruptions may have been responsible for the collapse of Classic Mayan civilization, which set the stage for the flowering of a Postclassic Maya flowering here at Chichén Itzá.

In a 2014 paper by Heajoo Chung and Youngsun Song appearing in "Mediterranean Archaeology and Archaeometry," entitled "The meaning of volcanic ash characteristics found in the archaeological pottery of Chichen Itza, Yucatan, Mexico," the authors speak of an eruption of El Chichón volcano in Chiapas, southern Mexico, near Yerba Buena Clinic from which I've often written. They say:

This isn't a universally accepted theory, but the authors do provide data emphasizing the importance of volcanic eruptions to ancient and modern Maya society. That paper can be freely downloaded in PDF format here.

*****

GARDENING BY THE MOON
A visitor passing through gave me some Cosmos seeds, which I planted, and now the seedlings are doing nicely. My friend says she'll deal with hers during the next full Moon.

It's an old question as to whether gardening by the Moon's phases makes any sense.

On the Internet any number of websites assure us that it does, and precise instructions are given on what to do, and when. Some studies indicate that there might be Moon-phase/garden connections, but those studies have been too small and uncontrolled to be embraced by the scientific community. In general it can be said that there's no convincing scientific proof that gardening according to the Moon's phases is more productive than not. The situation is summed up nicely at the Gardeningknowhow.com Website.

It's easy to see why belief in the power of the Moon's phases to influence gardens persists, even without proof that it does. For one thing, some of the most spectacular gardens are produced by gardeners who believe in it. But, anyone involved enough in his or her garden to plant according to the Moon's phases probably also will tend to water and weed the plants regularly, watch for bug outbreaks, keep the soil in shape, etc.

Also, it's just fun to believe in such things as that the Moon's phases exercise mysterious powers in some aspect of our lives. I've written about the influence of the Moon on me, and a Papaya tree, at https://www.backyardnature.net/n/p/081124.htm.

Still, my own gardening experience suggests that if Moon phases affect gardens at all, the effects are negligible compared to the influences of regular watering, weeding, watching for bugs and diseases, and assuring that the soil is rich and in good condition.

Moreover, with regard to those Cosmos seedlings my friend gave me, the thing that strikes me is that the seedlings came up so quickly, and are growing so robustly, whatever the Moon said. It's as if they really want to grow -- can hardly endure being small and sterile. I visit them several times each day, somehow participating in their joy of self-actualization.

For, I think that even plants, fungi, bacteria and every living thing, and maybe even things like storms, crystals, institutions and ideas have from their inceptions a certain self-contained spirit, and a need to grow, and to influence the world around them. Even the whole Universe seems to be growing with unimaginable vigor, and evolving with a kind of single-mindedness toward sentient beings who think and feel, even reflect on the Creative Impulse behind it all, behind US all.

Moreover, not only does it seem to me that there's majestic vigor and intention in this Creative Urge, but also what's created is created more beautiful than it needs to be, if its only goal is to be adapted to its environment. Who can look at a Flamingo or a snowflake without wondering what's really going on with such aesthetic perfection?

Anyway, with such thoughts rattling through my mind these days, the question of whether the Moon's phases might affect my plantings just doesn't come up. I have seeds, the weather is good, there's moist, crumbly soil provided by a pocket gopher who leaves it in hills next to the hut each morning, and I know that those seeds WANT to be planted, to grow and produce more seeds... and the sooner the better, no matter what the Moon says.

*****

NANCY'S CONFABULATION
In last week's Newsletter, Nancy, someplace in cyberspace, read my thoughts about "Three Levels of Seed Enchantment," and reciprocated by writing the following poem, which one morning before sunrise materialized on my laptop screen as I sat cross-legged on the floor of an unlighted, empty little room in an unused building within the Hacienda's wi-fi range, downloading mail:

This was pretty good. In fact, it seems to me that one of the highest callings of sentient, thinking beings in this expanding, impersonal Universe is to snatch insights, thoughts and feelings from the brink of oblivion, filter them through the influences of one's own genetic programming and experience, and pass them on.

Nancy has done this, and in doing so she's harmonizing with the evolving flow of the Universe, which itself trends toward ever greater interconnectedness, and, among Her sentient, intelligent creations, ever more exquisite sensitivity and insight. To poetize is to contribute color and substance to the Universe's expanding shell of influence -- like rainbow hues on a growing soap bubble.

And, here on little Earth, what a beautiful thing the way that thoughts and feelings can flash from point to point, like electrical impulses igniting here and there in a brain awakening to itself, struggling to grasp and harmonize and grow with Universal currents of the beautiful, and good.

*****

Best wishes to all Newsletter readers,

Jim

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