January 26, 2007

BLUE MOCKINGBIRDS
Earlier this week, before the chilly overcast and drizzle began, we had some days as sunny, warm and fresh as any early-May day in Kentucky. All that was missing was the rain and the lushness, for this is the heart of the dry season and things are showing it. Though the air smells moist and rich and the sunlight feels generous on the face, our mountain-slope plants are leafless, or else their evergreen leaves are getting dusty and dull, or they're showing drought-stress in other ways. Even leaves on willows and sycamores at the water's edge are yellowing, turning crisp and falling.

Still, along the reservoir's banks certain protected coves have managed to maintain a degree of shadowy greenness. Last Sunday morning as I passed by one such cove, below me suddenly there erupted a loud, rich CHOO! and a silhouette escaped furtively through shadowy underbrush. The bird didn't want me to see him but eventually I got him in focus. All I could see was his form -- longish tail with longish, slender beak -- but no colors at all, just blackness. Well, I'd heard that CHOO! before, from dozens of other shadowy underbrushes, so I didn't really need to see color to know who it was. It was the Blue Mockingbird, endemic to Mexico north of the Isthmus, a pretty picture of which you can see at http://www.southfloridabirding.com/bluemockingbird.jpg.

That picture shows a truly blue bird with the familiar long-tailed mockingbird shape. However, most of the times I've seen this bird I haven't glimpsed any blue at all. A black silhouette among black shadows is about right for this bird, along with its disjointed series of sharp, singly articulated and highly varied whistles, which sometimes are decidedly ventriloquial. You look at the bird, see his bill open and his throat pumping, but the notes are coming from a few feet to his side.

And this bird has another trick, too. After you try and try to get a good view as he manages to remain just a black shadow down among many black shadows, once you give up, he's very likely to abruptly fly onto a completely exposed perch and sing as unrestrainedly as any gringo mockingbird in a magnolia. One suspects a certain sense of humor in this bird.

Eastern North American birders know that mockingbirds, Brown Thrashers and catbirds are all members of the same family. Mockingbird songs usually consist of notes repeated three or more times. Brown Thrashers repeat their notes twice, and catbirds just string together a series of once-stated notes. Thinking in these terms, the Blue Mockingbird with his train of once-stated notes is close to the catbird. In fact, if you add a little blue to the dark catbird, you almost have our Blue Mockingbird.

But, our Blue Mockingbird has a bit more pizzazz than a catbird, more color, a stronger voice and certainly more quirkiness.

He's a perfect bird to call out CHOO! on a perfectly summery day in January, from a shadowy Mexican thicket on a perfect Sunday morning.

*****

SNOWY EGRET & NEOTROPIC CORMORANTS
For the last few weeks I've been seeing at least one Snowy Egret doing something I didn't know an egret could do. When he spots a school of fish near the reservoir's surface he flies into the school's center, lands in the water and while floating like a duck stabs with his long beak all around him. Often I see this bird come up with silvery fish in his beak, so the behavior seems to be working.

Snowy Egrets and all other egrets and herons are "supposed" to wade with their long legs in shallow water and spend lots of time standing frozen in place until a fish swims by, which the bird then snatches with his pointed beak, right? I told my ornotholigist friend Jarvis in North Carolina about this and he responded that "David Sibley wrote that researchers have described more than 30 types of foraging behavior in herons and egrets." Therefore, it's dangerous to stereotype an egret.

The story doesn't stop here. A small flock of Neotropic Cormorants always is fishing nearby and when they see the Snowy Egret plop onto the water's surface anywhere in the lake they all rush to participate in the fishing, knowing that the egret wouldn't have landed on the water if there'd been no school of fish there. The cormorants splash into the water and dive with such fervor, churning up the water something awful, that the heron usually looks a bit confused, then flies away.

However, the strategy works both ways. Sometimes the heron sees that the cormorants have located a school and are feeding nicely, so then the heron flies out into the lake and lands amidst the diving cormorants, who don't seem to notice or care about their visitor's arrival.

This isn't the only curious behavior I've seen lately on behalf of a long-legged shore-wader. The other day I saw three White-faced Ibises on a wooden fence next to a cow pen, along with about a dozen Cattle Egrets, scavenging whatever they could from the black mire the cattle stood in. Seeing Cattle Egrets do this didn't surprise me but who'd expect a nice White-faced Ibis to scavenge in a cow pen? They're supposed to be in "brackish and freshwater marshes," as the books say.

I'm glad these birds are showing such flexibility of behavior. That just may be what eventually saves them from extinction.

*****

ORCHID OUT ON A LIMB
Being so deep into the dry season, not much is blooming here other than the Sweet Acacias I told you about, and ornamentals planted and watered in people's yards. Still, the other day I was really tickled to find a cluster of epiphytic orchids growing on the completely leafless limbs of a tree next to the lake. You can see it at https://www.backyardnature.net/n/07/070126or.jpg.

The plant was past its flowering peak, its few remaining white blossoms faded and drooped. Still, in the lower, right corner of the above picture it's nice to see one of the plant's fruits. Also, if you look closely you can see the white roots that are so helpful in distinguishing orchids from other epiphytes such as bromeliads and ferns. Finally, at the base of the left-most leaf you can see that the flat blade connects at an articulation point with a swollen, green, football-shaped item known as a pseudobulb. Pseudobulbs are storage organs for water and photosynthesized carbohydrate. Most orchid species don't have pseudobulbs, so these structures are very helpful in orchid identification. And that's good, since the Orchid Family is the largest of all flowering-plant families; distinguishing its ±20,000 species can be a challenge, especially when you're identifying wild species in a country without fieldguides.

Best I can figure out, this orchid is NIDEMA BOOTHII, fairly common but apparently with no common name. Pictures of plants with flowers at their peak can be seen at http://www.abundaflora.com/nid_boothii.htm.

My plants have stubbier-looking blades than the ones shown above, but I think that leaves on wild plants growing on exposed tree limbs in a dry scrub forest tend to be shorter and thicker than blades on plants pampered with mistings and grown in partial shade.

Nidema boothii is distributed from Mexico to Panama and also Cuba and Surinam. Its habitat is tropical moist forest and scrub up to 5000 feet in elevation. Blossoms at their peak are strongly fragrant, though my past-prime flowers were odorless. The whole plant was rather small, about the size of a teacup.

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RUBY GRASS
I retain lots of vivid memories from my first trip through Mexico back in the late 60s. Until the very day before my trip began I really had no plan for what I'd do here. However, the day before I left, the postman delivered a National Geographic magazine happening to feature Mexico's archeological ruins. The next day I set out with that edition's map of Mexico with all the major sites highlighted, planning to visit as many ruins as possible during my month of hitchhiking.

I still remember the esthetic effect created by a certain red-topped grass that nearly always grew atop the ruins. Atop pyramids nearly always there was a nice breeze and a feeling of being closer to the sun, and nothing captured the feeling of mingling wind and sunlight more than a particular grass whose deep burgundy flowers shook in the wind and seemed to explode with light. You can see that same grass in a picture taken here in Jalpan at https://www.backyardnature.net/n/07/070126rh.jpg.

That's MELINIS REPENS, sometimes called Ruby Grass and Natal Grass. The plant's distinguishing features are that its individual florets are purple and abundantly hairy. It's the hair that catches sunlight, causing windblown inflorescences to be so spectacular when the sun shines from behind them.

I've always associated Ruby Grass with Mexican ruins but now I learn that it's an invasive species from southern Africa found worldwide in the tropics and a bit in the subtopics, especially in dry, disturbed areas. In US southern states usually it's confined to roadsides but in Mexico it's invaded natural grasslands, changing their species composition and structure. When Ruby Grass forms dense stands and catches fire, it burns so hot that native plants are killed, while Ruby Grass itself somehow comes back.

Well, this isn't the first times I've nurtured warm feelings for an acquaintance from way back, only to Google them and find out that they have been up to shady dealings elsewhere.

*****

RUSTY-TIPPED PAGE BUTTERFLY
You can imagine that we have some outstanding butterflies here, some of them truly gorgeous. There's no fieldguide to Mexican butterflies, but a Mexican butterfly expert, a lepidopterist, did study this Reserve's species and came up with a list of about 650 taxa. Happily, I have access to that fellow's unpublished, home-printed manuscript for a fieldguide for butterflies of Mexico's northern Gulf area, awaiting a publisher.

Therefore, the other day when a butterfly landed on the black charcoal of an old campfire next to me as I sat at the water's edge at the reservoir, I sneaked out my camera and took its picture, which you can see at https://www.backyardnature.net/n/07/070126bu.jpg.

Back home, I used the unpublished guide to identify the butterfly. It was SIPROETA EPAPHUS, which Google tells me is graced by the English name of Rusty-tipped Page. At http://www.nearctica.com/butter/plate17/Sepaph.htm I learn that this is a tropical species noted in the US only in one county in New Mexico, but found from northern Mexico through Central America to Peru. Its caterpillar stage eats plants of the Acanthus Family, of which we have plenty, and adults take nectar from "Croton, Cordia, Impatiens, Lantana, and Stachytarpheta; also rotting fruit, dung, and carrion," all of which we possess here in abundance.

What a treat to be able to identify a pretty, new-to-me butterfly. I sure hope that Roberto G. de la Maza Elvira, the dedicated lepidopterist who put this fieldguide together, finds a publisher. You can't imagine what barriers must be overcome by homegrown naturalists in the developing world. I admire anyone who can produce such a work as this under the conditions we have here.

*****

TANGERINES
Tangerine season is winding down here. It reached a peak around Christmas, when people's yard trees looked artificial because they bore so many bright-orange fruits. Marina here at the Reserve invited me one late afternoon to go to her mother's house to help her pick tangerines. We got onto a building's flat roof and picked about three bushels, hardly making a dent in the crop. By now surely the vast majority of the tree's perfect fruits have simply fallen and rotted, for many people have such trees, and it's just impossible to eat all the fruit. For a while a man parked a pickup truck full of them near my residence but he didn't sell many. Everyone had tangerines to spare. What a pleasant memory, though, of being atop that house, Marina hidden inside the trees' fruit-heavy limbs handing out tangerines in threes and fours to me, the limbs' spines scratching us, but somehow the scratches seemed just payment for the sweetness we were gathering, overindulging in.

Sunkist's online Tangerine Page at http://www.sunkist.com/products/tangerines.asp says that there are three major tangerine types: tangerines; mandarins, and; tangelos. Then each of these types has different varieties, such as the Fairchild and Dancy.

I'm not sure which variety ours is. They're deep, almost reddish orange and with just one thumbnail scratch across a fruit's top the peel comes loose. I've never seen tangerines with such loose-fitting skin, and a whole fruit contains only two or three soft seeds. Sometimes I eat the peel itself. It's like wanting to experience even the dark side of a beautiful woman: Maybe it's a need to complement the sweetness with bitterness, if only to attain esthetic balance.

It's sad to see fruits rotting on trees, and white fungus-pustules appearing on otherwise perfect fruits heaped in marketplace bins.

But, every season passes and something else comes along. Oranges are still at their peak. The next thing to look forward to, I'm told, in mango season in April.

If you know the tangerine varieties maybe you can tell me what kind we have. A picture of one in my hand is at https://www.backyardnature.net/n/07/070126ta.jpg.

*****

MOVED FROM DOWNTOWN
I no longer lodge in downtown Jalpan where boom-box thundering jars my windows day and night. I've moved into the Reserve's entrance guardhouse, which you can see at https://www.backyardnature.net/n/07/070126hu.jpg.

It's just big enough for a desk and a place to sleep, but it's much better than being downtown. Maybe someday I can find a place with a garden and a spot for a campfire, but for the moment this is fine.

*****

CORN, HIBISCUS & NUCLEAR WASTE
Don Gonzalo does a good job planting ornamentals on the Reserve-office grounds and keeping things watered. This week on the path next to the Computer Room I noticed two plants that put me in a certain train of thought by the time I'd reached the path's end.

First there was a flowering corn plant with messed-up flowers. A normal corn plant is topped with an inflorescence of male flowers -- the tassel -- while spikes of female flowers (the future "ears," with the emerging "silks" being super-long styles) arise where the leafblades attach to the stalks. If you need a review of corn-flower anatomy, see my page at https://www.backyardnature.net/fl_corn.htm.

However, this corn plant's tassel, instead of being branched the usual way, consisted of nothing but a single spike of male flowers pointing straight upward. Moreover, instead of female flowers being down below where ears of corn are supposed to develop later, a few female flowers appeared at the base of the single vertical spike -- where there should have been nothing but male flowers -- and there was nothing below! You can see all this at https://www.backyardnature.net/n/07/070126co.jpg.

Not ten feet beyond the confused corn plant there was a hibiscus blossom also doing something abnormal. At https://www.backyardnature.net/fl_hibsc.htm you can see what a normal hibiscus flower looks like. Especially notice how a hibiscus flower's pollen-producing stamens arise from a cylinder surrounding the flower's style. Well, my path-hibiscus blossom's staminal column bore a few stamens at its top, but below them arose several items that were half stamen, half petal. You can see these, runty, deformed, red petals arising where only yellow-anthered, pollen-producing stamens should be at https://www.backyardnature.net/n/07/070126hb.jpg.

Actually, it's not uncommon to see such half-stamen, half-petal monstrosities in horticultural plants because many of our "double-blossomed" varieties have extra petals precisely because it's so easy for plant breeders to coax extra petals from stamens. In many garden rose blossoms you can see the same thing, an excellent example of which appears at the bottom of my Rose Page at https://www.backyardnature.net/fl_roses.htm.

Such abnormalities can appear so frequently because of this: We living things are sublimely complex and fragile electrochemical machines put together according to blueprints. Those blueprints are chromosomes carrying encoded information. And we all know that, with any complex set of instructions, having part of the instructions missing or illegible can lead to some awful problems.

So, here's the thought I ended up with after seeing the messed-up corn and hibiscus: Information encoded in our chromosomes is the most precious, complex stuff on Earth; yet it is profoundly fragile, and can be scrambled or lost very easily, with profound results.

And then: Of all the Universe's agents, nothing is more dangerous to the integrity of that information than chromosome-smashing radiation emitted from degrading, unstable nuclear material.

And nuclear material introduced into the environment today will be capable of killing living things and deranging genetic information in all forms of life for thousands of years to come.

It's good that finally we're talking about global warming. However, we mustn't lose sight of the fact that the coming wave of newly built nuclear-power plants, and the ever-growing list of countries with nuclear weapons, present much more of a long-term danger to Life on Earth than global warming.

For, after a few centuries of dealing with global warming, we'll still be human. But, once radioactive waste and war debris is dispersed throughout the Earth- ecosystem, who knows what monstrosities will emerge from US -- like female flowers in a corn plant's stunted tassel, like the hibiscus flower with parts that are neither this nor that?

The Sierra Club's page on nuclear waste is at http://www.sierraclub.org/nuclearwaste/.

*****

Best wishes to all Newsletter subscribers,

Jim