April 17, 2011

TROGON AT THE SECURITY LAMP
For weeks in early mornings one or more Violaceous Trogons have perched near a certain security lamp in the parking lot from where for half an hour or so they repeatedly fly up to the lamp and peck at it, as shown at https://www.backyardnature.net/n/11/110417tg.jpg.

I'd always thought of trogons as strictly fruit-eaters but it looks to me as if these birds are picking off bugs attracted to the light at night. At dawn the bugs apparently crawl up the outside plastic shade and shelter between the top of the shade and the metal rim it fits into. Consulting Howell's A Guide to The Birds of Mexico and Northern Central America, I read that trogon food is "mostly fruit and insects plucked from outer branches and foliage in short sallying flights," so Howell already knew what I'm just finding out.

While photographing one trogon's bug-plucking forays I got the interesting shot shown at https://www.backyardnature.net/n/11/110417th.jpg.

What fascinates me is the large amount of space between the wing feathers. Finally I realized that since the trogon is flying upwards he must orient his feathers horizontally within his vertically aligned wings, to provide the most wing surface-area for pushing down against the air. Seen from the side it's like looking through Venetian blinds with their vanes set in the horizontal position. I don't think I've ever seen a bird exercising such control over individual wing feathers.

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YELLOW WARBLER IN A GUMBO-LIMBO
Atop a dry-season leafless Gumbo-Limbo tree the unmistakable silhouette of a slender-beaked, busily foraging wood-warbler caught my eye. It's spring migration time, so it's exactly the time for this. You can see the bird eyeing some Gumbo-Limbo fruit pods at https://www.backyardnature.net/n/11/110417yw.jpg.

This is a male Yellow Warbler, DENDROICA PETECHIA, in full courtship plumage, with those thin, rusty streaks running down the yellow breast making identification easy. Up North I associate Yellow Warblers with willow thickets in swamps and along streams, so this one looks a little out of place in a Gumbo-Limbo. However, that's the way it is with migrants, their overwintering grounds usually being very different from their summer breeding ones.

Here in the Yucatán Yellow Warblers are only winter visitors, so the bird in the picture probably is leaving the area and won't be back until August or so. I'm guessing that he'll soon fly over the Gulf of Mexico onto the US Gulf Coast. However, some overwintering Yellow Warblers migrate into summer homes in Mexico's Western Sierra Madre highlands, so it's conceivable he'll go there instead. The species winters south to Peru and Brazil, so this may not be a bird who's overwintered in the Yucatán, but rather one "just passing through" from South or Central America.

Why would a Yellow Warbler be foraging in a leafless Gumbo-Limbo tree? The tree, Bursera simaruba, is very resinous and I've seen insects attracted to the resin. I'm betting the bird was going after those insects.

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ROSE-BREASTED GROSBEAK HEADED NORTH
It was the same story with the Rose-breasted Grosbeak, PHEUCTICUS LUDOVICIANUS, shown in another Gumbo-Limbo at https://www.backyardnature.net/n/11/110417gb.jpg.

Again we had a winter visitor migrating north, and again he looked a little strange in a Gumbo-Limbo, the tree in the picture more concerned with flowering than fruiting. In the US Southeast we see Rose-breasted Grosbeaks only during migration, so I associate the species with cool weather. However, the bird in the picture visited on a day when the temperature rose well over 100° (38°). What an amazing thing that these little birds not only fly across the Gulf of Mexico, but also survive the extreme weather changes they encounter on arrival.

I heard this bird's loud, sharp PEEK! call before I saw him. He seemed to be craning his neck, trying to find the source of the sound made by my water faucet as I filled a bucket.

Rose-breasted Grosbeaks winter from Mexico to Peru.

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DOUBLE-WHAMMY CATERPILLAR
Next to the septic-tank hole I'm digging with a shovel each morning for an hour or so, for exercise, stands an orange tree. One morning this week, on a stem of the orange I noticed the amazing caterpillar shown at https://www.backyardnature.net/n/11/110417ct.jpg.

The caterpillar, about two inches long (5cm), is remarkable because not only is it well camouflaged as a fresh dropping of bird poop, but also its front end looks like a reptilian or amphibian head, better shown at https://www.backyardnature.net/n/11/110417cu.jpg.

To me the head looks like it belongs to a gecko or other kind of lizard, but others say it's a snake's head. Whoever the head looks like, the fake eyes, nostrils and wide mouth could be disconcerting to any predator approaching from the side or front.

Naturally I sent photos of the caterpillar to Bea in Ontario, who immediately recognized it as a member of the Swallowtail Family, the Papilionidae. Starting with that, it wasn't long before she knew we had one of two species: Either it was the caterpillar of the Giant swallowtail, Papilio antimachus, or else of the very similar Thoas Swallowtail, Papilio thoas. Since we've identified Thoas Swallowtails here and not Giants, we figured that the caterpillar is that of the Thoas Swallowtail, the adult butterfly of which is at https://www.backyardnature.net/yucatan/mariposa/butt040.jpg.

However, an expert Bea double-checked with in the US thinks that Thoas butterfly caterpillars probably feed on members of the Black Pepper Family, the Piperaceae, while Giant Swallowtail caterpillars feed on citrus, so he's guessing that it's a Giant Swallowtail. So, we can only say that it's one of the two species.

In citrus growing parts of the southern US caterpillars of the Giant Swallowtail are known as orange dogs or orange puppies, presumable because they feed on leaves of orange trees, doing considerable damage.

When I took the above pictures I didn't know one of the most fascinating facts about this caterpillar. That is, in addition to looking like bird poop and a lizard's head, each larva possesses an "osmeterium," which is an orange or reddish, Y-shaped, eversible gland located just behind the head. When attacked by small predators such as ants or spiders the caterpillar extrudes the gland so that it looks like an orange or reddish antler, and tries to wipe it against the attacker. The osmeteria of older caterpillars contain a highly noxious, pungent chemical that smells like rancid butter.

The day after I took the above pictures I returned to the tree hoping to antagonize the caterpillar into extending osmeterium, but he was gone, or least better hidden than when I'd earlier found it. But you can bet that the next one I see I'll try to see that osmeterium.

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CILANTRO/CORIANDER FLOWERING
Cilantro, or Coriander -- CORIANDRUM SATIVUM -- is such a commonly grown and used herb in Mexico that one tends to ignore it. This week, however, I had the good sense to pause awhile, admire and exchange vibes with some plants in the garden. You can see one of them, a plant that grew so tall that it fell over, at https://www.backyardnature.net/n/11/110417cq.jpg.

Cilantro belongs to the Parsley Family, the Umbelliferae, and one of the most diagnostic features of species in that family is that small flowers are clustered into "umbels" -- flat-topped flower clusters whose flower stalks, or pedicels, arise from a common point, like an umbrella's stays. Cilantro's flowers gather in "compound umbels," which means that secondary flower groupings, or "umbellets," are themselves held in umbels. You can see an umbellet at https://www.backyardnature.net/n/11/110417co.jpg.

In that umbellet, notice that two outside flowers bear oversized petals growing outwards. These oversized petals distinguish Cilantro from other closely related and similar species. You can see some Cilantro fruits at https://www.backyardnature.net/n/11/110417cp.jpg.

Notice the pale, slender styles still attached atop those fruits. Later they'll fall off. Technically, Cilantro fruits are "schizocarps," which are dry fruits that split into two halves, each half referred to as a "mericarp." A "ternately decompound" leaf, which I held against the sky admiring a good while, is at https://www.backyardnature.net/n/11/110417cr.jpg.

During my Cilantro-admiration time, Cilantro's pungent odor blossomed around me, reminding me of the wonderful Mexican salsas and guacamoles, and homemade gringo salads, I've enjoyed garnished with Cilantro leaves. When I took the fruit picture I thought of the fabulous sweet pickles my mother used to can in Mason jars, with Cilantro fruits serving as a pickling spice.

And finally I thought of Cilantro's medicinal uses, its antioxidants, its proven antibacterial activity against the cholera bacteria, its traditional use for diabetes, and more. Wikipedia's Coriander Page lists an impressive array of culinary and medicinal uses at http://en.wikipedia.org/wiki/Coriander.

Despite Cilantro being so important in Mexican cooking, it's not native, was instead introduced here by the Spanish. Originally it seems to have grown in the Near East and southern Europe, though it's been introduced into so many lands that its origin is hard to pinpoint. About half a quart of Cilantro mericarps were found in Tutankhamun's tomb. Even the Bible, in Exodus 16:31, mentions Cilantro, describing Manna as "round like Coriander seed... "

So, Cilantro qualifies as one of humanity's most enduring, useful and cherished herbs. To me its odor and taste go beyond mere sensory experience, into a realm where history, beauty and usefulness all meld into something transcendently "good."

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BROMELIADS ISSUING SEEDS
You've seen that of all the epiphytic plants gracing branches of our local trees, the basketball-size bromeliad known as Tillandsia fasciculata is the most conspicuous. You can see the plants and flowers at https://www.backyardnature.net/yucatan/tilland1.htm.

Nowadays many Tillandsia fasciculatas bear mature pods splitting open to release into the wind large numbers of tiny, slender seeds, each seed equipped with white, parachute-like fuzz that helps the wind disseminate the seed into new territory. Sometimes fuzz masses accumulated among the open pods glow intensely when lit from behind by the morning sun, as shown at https://www.backyardnature.net/n/11/110417fz.jpg.

A close-up of some slender, brownish seeds, showing how each seed is topped by fuzz as well as perches atop a white, silky podium, is shown at https://www.backyardnature.net/n/11/110417f~.jpg.

This fuzz configuration is a little different from that of the seeds of Spanish Moss of the US Deep South. Spanish Moss is a member of the same genus as our common bromeliad here -- Spanish Moss being Tillandsia usneoides. You might enjoy comparing Yucatán's Tillandsia fasciculata fuzzy seeds with Spanish Moss's fuzz-footed seeds at https://www.backyardnature.net/n/h/spanmoss.htm.

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AGAVE PLANTLETS
Last October we met a spiny-leaved agave producing a 15-ft-tall (5m) flower spike growing wild in the woods here. It was Agave angustifolia, and we mentioned how hard it is to identify agaves here, especially because ancient indigenous people in this area transported various agave species long distances because of the agaves' usefulness as food and fiber. That agave page is at https://www.backyardnature.net/yucatan/agave.htm.

Near the hut an agave of the same species has produced fruiting pods, and died -- for agaves do generally die after they produce their fruits. The plant's 15-ft- tall panicle, with most of its fruit capsules already empty of seeds and dropped off, is shown at https://www.backyardnature.net/n/11/110417ag.jpg.

What's interesting about that fruiting head is that the lower panicle branches bear, instead of seed-bearing capsules, dense clusters of sterile, miniature versions of the agave itself, which can fall off, root, and grow into a clone of the mother plant. A close-up of one of the clusters is shown at https://www.backyardnature.net/n/11/110417ah.jpg.

A close-up of some empty capsules mixed with several small, vegetative plantlets is at https://www.backyardnature.net/n/11/110417ai.jpg.

To help with identification, I also photographed a rather distinctive part of a younger, living plant seeming to have budded off the dead one. In the picture you can see how the thick blades with their weakly spiny margins bulge at their bases where they connect with the main body, and are covered with a silvery bloom -- a heavy glaucescence. The blades end in a very dark, stiff, sharp spine. The sharp but spindly marginal spines sometimes curve backward, sometimes forward.

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LITTLE GREEN-SPECKLED CUCUMBER-THINGIES
Last week I introduced you to some "little orange cucumber-thingies" found along the road south of Pisté. What I didn't say then was that, amazingly, intermingled with the dry, leafless remains of that orange-fruited Cayaponia vine was yet a second dead, dry, leafless, non-woody, viny species with tendrils, and fruits developed from inferior ovaries -- another member of the Cucumber Family -- but this vine bore little GREEN-SPECKLED cucumber-thingies, as shown at https://www.backyardnature.net/n/11/110417do.jpg.

A longitudinal section of the cucumbery fruit appears at https://www.backyardnature.net/n/11/110417dp.jpg.

Finding two strange, seldom seen members of the Cucumber Family -- the only ones of these kinds noticed along the whole road -- twining within one another in the same spot just seemed too unlikely. And yet, there they were, and who knows how to explain it?

This second species was even more poorly known to science than last week's Cayaponia racemosa. It was DOYEREA EMETOCATHARTICA, documented from dry forests in southern Mexico, Guatemala, the Caribbean and northern South America -- and now we know also here in the Yucatán. An unusual feature of this Cucumber-like plant is that its base is much swollen, looking almost like the trunk of a tree, and its stems are succulently thick and fleshy. It's also somewhat unusual that the plant is flowering here in the dry season when its climbing stems are leafless.

With a species name like emetocathartica -- emetics being used to induce vomiting, and cathartics employed for purging the bowels -- you'd expect the plant to be of medicinal value. However, I can find no reference to that. In fact, there's very little information about this peculiar vine at all, so, once again, we're doing a good deed for the botanical world just by posting our pictures and what little information we have about it here.

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SIESTA
I think every day this week the early-afternoon temperature in the shade at the hut's door rose to over 100° (38°C). The humidity wasn't too high, though, so if you kept in the shade and didn't move around much it wasn't bad. In fact, since I jog well before dawn and spend an hour or two each morning shoveling out a hole for a septic pit, by the time it's that hot I'm ready for a brief snooze, and when I lie down it's actually very pleasant.

A breeze passes through the hut, blowing right between the wall poles, and the wind's sound soughing through the surrounding trees and rustling the roof's thatch is very soothing. Birds are relatively subdued, but still a few manage to call, especially doves with their moody, monotonal ooooooohs. When it's that hot you sweat all the time, but evaporation cools you off, and somehow it feels good when the body reaches its sweat/evaporation equilibrium. Just lie there in the dim hut feeling the soft breeze, listening to the peaceful sounds, letting the mind drift...

But, of course, it's not that simple. I'm a gringo who came of age in conservative rural Kentucky where people were expected to work, not take Mexican siestas. During my early afternoon siestas I always feel a little guilty. Childhood programming is hard to undo, and if a genetic component against afternoon siestas comes with my blue eyes, that's hard to overcome, too.

One way I deal with the guilt is to ask myself just who decided for everyone that people are supposed to work eight-hour days, from nine to five, or thereabouts. Who decided that departing from "normal workaday schedules" was lazy, antisocial, and maybe even sinful?

Also, I keep in mind that my Northern culture not only sniffs at afternoon siestas, but also builds suburbs without sidewalks, and when houses go up, first the developer cuts all the shade trees, then ignores building orientation with regard to natural cooling in the summer, and solar heating in the winter. Nowadays up North even windows are sealed and can't be opened if a pleasant spring breeze is blowing.

Thinking like this, I nod off, in defiance, if nothing else. Then in a few minutes I awaken amazingly refreshed for such a brief rest. Maybe a dried leaf scraping in the wind against the hut's outside wall will have awakened me, or the soft chuckle of a robin calling from deep shade, or the little-feet-on-loose-dry-bark sound of a fly-chasing gecko scampering across the hut's pole walls.

And somehow I think it's a good trade. On the one hand I have to put up with the heat. But, on the other, I'm where no one blames you if you lie low during the day's hottest hours, and where a nice cooling breeze filters from shade trees all around, and passes right through your little hut's walls.

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Best wishes to all Newsletter readers,

Jim