November 19, 2007
A BLUE-AND-WHITE MOCKINGBIRD
I heard the beautiful, familiar, before-the-rain song of the Northern Cardinal, si-weet si-weet si-weet and though I've not yet seen North America's "Red Bird" here I wasn't surprised. We're at the southernmost limit of the Cardinal's distribution and the species makes its home up to 1800 meters in elevation (5900 ft), so it should be here.
But then the song started breaking up, notes were introduced I've never heard a Cardinal articulate, and finally the song flipped into something gurgly no Northern Cardinal has the savoir faire to whistle.
The bird flew across my path and landed in shadows enabling me to see its thrasher-like silhouette: Slender body, long tail and a slender, slightly down-curved bill. A puff of wind for half a second opened the forest's canopy and a shaft of light illuminated a slaty-blue top. So, this was no kind of thrasher.
When the bird flew again I saw its slaty-blue top, white underparts, and black mask. It was exactly like the Blue Mockingbird along the lake back in Jalpan in Querétaro except for the white underparts. In fact, it was the very closely related (same genus) Blue-and-white Mockingbird, MELANOTIS HYPOLEUCUS, shown at http://www.birdguatemala.org/bigjpegs/Blue-and-white_Mockingbird.jpg.
Blue Mockingbirds live as far south as Oaxaca but, being partial to arid habitats and uplands, so far they haven't crossed the moist, lowland Isthmus of Tehuantepec to this side. Blue-and-white Mockingbirds, being highland birds, aren't found on the other side of the Isthmus, and are in fact endemic from here through the Guatemalan mountains to Honduras.
It's easy to imagine that at one time the Blue and Blue-and-white Mockingbirds were the same species, but then as the Tehuantepec lowlands grew hot and humid, maybe as an ice age ended, the population fragmented into two groups. West of the Isthmus Blue Mockingbirds evolved adaptations for arid habitats while to the east Blue-and-white Mockingbirds adapted to moister uplands. Or maybe the similarities result from some other process entirely. What's certain is that the Blue and Blue-and-white Mockingbirds are very closely related species, what's called "sister species" nowadays, meaning the two species arose from a common ancestor.
What a beautiful bird this Blue-and-white Mockingbird is, and how good to hear his song beginning with such a familiar melody, then gradually jazzing up the tune as if he were playing with me.
CHIAPAS'S HAIRY WOODPECKERS
The first time I saw a Hairy Woodpecker here in Chiapas my heart skipped a beat, for it didn't look like any woodpecker I'd ever seen. It was just like the Hairy Woodpecker that's fairly common coast-to-coast in North America, including most of Canada, except that its throat and underparts were a definite tan color, not white as in every Hairy I'd ever seen. Also maybe it was a little smaller and shorter-billed than North America's Hairy. At that time I only had the Peterson Field Guide to Mexican Birds and that didn't illustrate the woodpecker I was seeing, or say anything about a tan-breasted Hairy look-alike.
Eventually Howell's masterpiece on the birds of Mexico and Northern Central America came out and finally I understood. As with many plant and animal species with extensive distributions (Hairys occupy upland pine-oak and oak forests all the way to Panama), the species has fragmented into subspecies. Our Chiapan subspecies is PICOIDES VILLOSUS ssp. SANCTORUM, and it's brownish below.
Actually, even Howell leaves me scratching my head a little, for his illustration of the sanctorum subspecies shows a bird with much darker underparts than what I see here, and a whiter back. Our birds have equally tan backs and underparts, but a pure white eye-stripe.
Howell states that our southern birds are a little smaller than the northern ones. In fact, there's an ecological rule, Bergmann's Rule, which asserts that "geographic races of a species possessing smaller body size are found in the warmer parts of the range, and races of larger body size in cooler parts." This makes sense. Species in cold climates have problems losing heat as it radiates from their body surfaces. It's a physical fact that a large sphere has less surface area per unit volume than a smaller one. Therefore, a large sphere would radiate less heat from its surface area than a small one, and the same would go for animals.
One can imagine that if Hairy evolution should continue in its current direction eventually there'll be a larger, white-breasted northern species, and a smaller, brown-breasted southern species.
WIDE-RANGING WOOD SATYRS
Speaking of organisms with large distributions, certain butterfly species are pretty wide-ranging, too. As I continue enlarging my "Upland Chiapas Butterfly Page" at http://www.backyardnature.net/chiapas/butter01.htm I'm surprised at the number of species found both here and in North America.
For example, does the Wood Satyr shown at http://www.backyardnature.net/chiapas/butt-009.jpg look familiar? In the US that's known as the Carolina or Hermes Satyr. It's HERMEUPTYCHIA HERMES, distributed from New Jersey through here to who-knows how far south?
I regularly see Monarchs and we also have American Painted Ladies and Checkered Skippers, both distributed from Canada to here and beyond. Several other species are distributed from southern Texas and southern Florida through here.
SQUASHED BLACK COFFEE-SNAKES
Jogging at dawn on Tuesday morning I almost stepped on an earthworm-size, car-flattened, blackish snake with an orange ring around his neck. It looked a lot like North America's Ringneck Snake, but not exactly. He wasn't too squishy so I slipped him into my pocket and carried him home with me.
I don't have a guide to the reptiles of Chiapas but I do still carry the wonderful book I used in the Yucatan, Jonathan A. Campbell's Amphibians and Reptiles of Northern Guatemala, the Yucatán, and Belize, published in 1988. In the illustration section I found a good match. A picture showing my roadkill specimen atop the book's photo I matched it with is at http://www.backyardnature.net/n/07/071119bc.jpg.
As you can see, the matching picture in the book is identified as the Black Coffee-Snake, NINIA DIADEMATA. The species is distributed from east-central Mexico to central Honduras, and in Guatemala it lives up to 1830 meters in elevation, so it should occur here. Campbell further says that the snake is secretive, usually hidden in abundant leaf litter or other ground cover where it feeds almost exclusively on slugs. When I hiked to town Thursday I found yet another Black Coffee-Snake, also run over by cars, so if this is a secretive species usually hidden in leaf litter, something must be causing them to roam right now.
Campbell provides fine identification keys so I set about "keying out" my roadkill to be more certain of its identification, especially because the white belly of the snake in the picture is whiter than mine. Working through the key I confirmed: Dorsal scale rows 19; anal scale entire; dorsal scales keeled; venter with a series of dark spots down middle... It keyed out exactly to Black Coffee Snake. Maybe the darker belly of our snakes is a local variation, or maybe the bellies of squashed coffee snakes just turn dark.
There's a Red Coffee-Snake, Ninia sebae, a coral-snake mimic, and it also should be found here.
I always check mud for tracks, such as those shown at http://www.backyardnature.net/n/07/071119sk.jpg.
In that picture you see fallen pine needles in the middle of which there's a bird footprint, then below to the left and above at the right are the tracks that got my attention. Here's how I diagnosed those:
First, these are really small tracks. The print at the lower left is only about the size of my thumbnail, so we have a rat-size animal.
The top-right shows prints of the animal's left feet while the bottom-left prints are of the animal's right feet. Keeping in mind that the trail travels from left to right, the animal's right-side feet are a fair distance from its left-side ones, so we have an animal that's fairly broad for its size, one that surely waddles as it walks. In terms of forward direction, the front tracks are fairly close to the back tracks, so we have a short creature with a short stride, not a long one who bounds from spot to spot like a weasel.
Even before analyzing the tracks I was thinking "skunk" because the lower, left print shows a broad, flat pad with five forward-pointing, sharply clawed toes. In North America the Striped Skunk prints I'm used to are larger than these, but they do have that broad pad and forward-pointing toes.
In upland Chiapas we also have Striped Skunks, as well as Hog-nosed and Spotted Skunks. Striped and Hog-nosed Skunks are "regular sized" but maybe you remember my encounter at Komchén in the Yucatan with a rat-sized Spotted Skunk who chased me down the road, the story at http://www.backyardnature.net/yucatan/spotsknk.htm.
That aggressive little critter also was encountered in mid November.
Therefore, I'm almost certain that the picture shows skunk prints, wouldn't be surprised if they belong to a Spotted Skunk, and I'd like to believe that the poor creature who left the print was a male wandering around in the evening in the same hormone-crazed, pathologically brash state of mind as that one back at Komchén.
The other day as I descended the slope on a weedy trail I spotted some big, glossy-black blackberries that looked so succulently sweet and inviting that without thinking much about it I reached down as I passed by, pulled a few off, and threw them into my mouth.
I returned to the bush, looked closer and saw what's at http://www.backyardnature.net/n/07/071119ln.jpg.
Clearly that's no blackberry, though the plant had been growing up through some leafy blackberry canes, so at least my mistake hadn't been entirely reckless. Typical blackberry leaves are "digitally compound," with leaflets arising from atop a petiole like a hand's "digits," but this plant bears simple, or undivided, leaves. In fact, the leaf shape and the leaves' crinkly surfaces ("rugose" in botanist terms) made me think of weedy Lantanas.
In fact, it is a Lantana, but I'm not sure which one since the flowers have long since fallen away as the fruits enlarged and matured.
You can see the yellow, pear-shaped, 1.5-inch-long fruits and 10-inch-long, leathery, evergreen leaves that are glossy above but with dense, rusty-brown, woolly hairs underneath on a commonly planted tree here at http://www.backyardnature.net/n/07/071119lq.jpg.
Local folks call the 20-ft-tall tree Níspero and seem to like its succulent fruits despite their containing large, brown seeds and having pretty acidy flesh. To my taste they're OK but nothing to sneeze about. Several people have told me they like to suck the sour juice from them. I read that slightly immature fruits make good pies, the mature fruits make outstanding jams, jellies and chutneys, and that they're simply delicious poached in light syrup. You can see some cut-open fruits containing one, two and four seeds, at http://www.backyardnature.net/n/07/071119lr.jpg.
It's a little unusual for a fruit to be so lackadaisical about its number of seeds. The plant's original inferior ovary starts out with two to five cells, or carpels, with two ovules in each carpel, but then natural abortion takes place so that hardly ever do more than five seeds form. Maybe one in ten of the fruits of the tree near my dwelling contain five seeds while maybe 80% hold either two or three.
Despite the trees being so popular here Nísperos are originally from China. However, they've been introduced throughout the world's tropics and today are commonly seen in Hawaii, southern California and southeastern Texas. In English they're called Loquats, the name a corruption of the original Cantonese name which literally meant "Reed Orange." The scientific name is ERIOBOTRYA JAPONICA and it's a member of the Rose Family.
Once you realize that the plant is a Rose-Family member it's easy to start thinking of the fruits as oversized, sour, firm-fleshed cherries.
Flowering prettily now in the very weedy garden abandoned because the invaders were threatening to invade more is the violet-flowered herb seen at http://www.backyardnature.net/n/07/071119ad.jpg.
In Spanish the plant is called Violeta del Campo, which means "Field Violet." Of course it's not a real violet at all -- not a member of the Violet Family. It's ANODA HASTATA of the Hibiscus Family. The flower is about two inches across, or 5 cm.
Anoda is a native American genus containing about 24 species, several of which are found in Mexico. One, Anoda cristata, is listed as a weed in Weakley's Flora of the Carolinas.
In the picture, the two green things below the flower looking like wheels with radiating spokes are immature fruits subtended by five-pointed calyxes. Such flattish fruit-disks with radiating lines are somewhat distinctive for Anoda. The radiating lines represent partitions between the fruit-disk's carpels, a carpel being a cell in an ovary. When you slice a tomato, the triangular, slice-of-pie divisions inside are carpels. Therefore, we can see that ovaries in the genus Anoda have many carpels. This distinguishes the genus from Hibiscus, for example, whose ovary contains only five carpels.
Plants in the genus Anoda also often bear leaves with pointed basal lobes attached at right-angles to the midrib, as shown in the picture. Leaves with such lobes are said to be "hastate" or "halberd shaped," a halberd being a 15th- and 16th-century weapon with a spearhead of such a shape.
CHIAPAS'S GENERAL PHYSIOGRAPHY
You might be interested in seeing how Chiapas's landscape can be divided into seven physiographic units at http://www.backyardnature.net/chiapas/physiog.gif.
On that map the chilly uplands are greenish while the hot lowlands are tan color. Notice that Yerba Buena resides in the center of the Northern Highland section.
1) The Gulf Coastal Plain in the north is a hot, humid, lowland area currently largely underwater because of heavy rains and runoff from the deforested slopes of the next two regions. Originally marshes and patches of borderline rainforest grew on the Coastal Plain alluvium but now most of the lowland has been converted to pastureland and banana plantations.
2 & 3) The Northern & Eastern Highlands consist of alternating mountain ranges and valleys, mostly between 1200 and 2200 meters high (4000-7200 ft). You can see a typical view across the valley I live next to at http://www.backyardnature.net/n/07/071119gl.jpg. Mountain slopes harbor a variety of vegetation types, depending on elevation and exposure, but deforestation has devastated the ecology of all slopes.
4) The Central Plateau is a chilly highland mostly between 1200 & 2200 meters in elevation (4000-7200 ft) that can be hilly but isn't deeply dissected like the Northern and Eastern Highlands. Bedrock is mostly Cretaceous limestone developing karst topography, with some volcanic outcrops. Pine species are most common in most places but sometimes oaks predominate. Logging, firewood gathering and farming has impacted the area tremendously.
5) The Central Depression is a hot, relatively arid lowland dominated by much-disturbed, low, spiny scrub forest growing on alluvium between 420 and 800 meters (1400-2600 ft) in elevation. Much of the foothills' semideciduous woodland has been converted to coffee plantations.
6) The Sierra Madre of Chiapas is a mountain chain averaging 1500 meters (5000 ft) high in the northwest to 3000 meters (9800 ft) in the southeast, composed mostly of granitic and metamorphic rock of Precambrian and Paleozoic age. Chiapis's highest peak, Tacaná Volcano, rises to 4,060 meters (13,320 ft) on the Guatemalan border. These altitudinal variations support many vegetation types, much impacted by man.
7) The Pacific Coastal Plain is a band of hot, lowland alluvium 20-30 kms broad (12-19 miles) along the entire Pacific coast. Originally this region was occupied by thorn forest but now it's been cut, burned and converted mostly to open agricultural wasteland with little of the natural forest remaining. Species-rich mangrove forests sometimes occur between shore and the sea.
The invaders who years ago forcibly took possession of Yerba Buena's nature reserve and began planting crops and gathering firewood there have accepted an offer from the government to accept money so they can buy new land for themselves, and leave.
Already most of the cabins have been abandoned. However, when I spoke with the invader chief last Saturday he told me I still couldn't enter the reserve to begin establishing a nature trail and to study overwintering bird-migrants. I need to wait two more weeks, he says, giving no reason.
The rate of firewood gathering in the Reserve has increased dramatically. Every day the same people return, pile firewood along the road and trucks come to haul it off. Clearly the firewood is being sold commercially and enormous ecological damage is being done, but the political reality is that we can do nothing about it.
The other day a small group of students from the Adventist college below us came exploring the trail leading to my dwelling. When they saw my building they turned around. The next morning when I walked past the spot where they'd been I found the wilted nosegay shown at http://www.backyardnature.net/n/07/071119ng.jpg.
"Nosegay" is an old-fashioned word we don't hear nowadays because people no longer bother with nosegays. But, just look at the neat manner by which someone has tied the flowers together with a grapevine tendril. In our culture do children ever bother with anything as simple and detailed as a nosegay?
My impression of North American culture is that -- with a few isolated and beautiful exceptions -- our people, and especially young people, not only "don't have time" to do things like create nosegays, but also have simply lost their taste for all simple, subtle features of life.
Having said that, a question arises: By losing nosegays, has our culture really lost anything of importance?
We have, and here's why:
Hectic, industrial-strength lifestyles in which there is no time or disposition for creating nosegays not only are unsustainable but unhealthy. Fast-moving, sense-bombarded lifestyles consume enormous energy and natural resources, leave huge carbon footprints, are hard on the nerves and digestion, and leave too little time for reflection, clearing the mind, and spiritual development.
The loss of nosegays, then, is like the death of a canary in a coalmine with ever-higher levels of poisons contaminating the air: It's a foreboding sign, a clear warning.
The main corrective measures are: Simplification; lowering the volume and intensity on everything; more time spent developing one's spirituality (not religiosity), and; if there's a child around whose nerve endings haven't already been blasted into oblivion by sensory overload, go make a nosegay with that kid.
Best wishes to all Newsletter subscribers,