March 16,  2009

ALLIGATOR DAYS
One afternoon this week Karen and I returned to St. Catharine National Wildlife Refuge just south of Natchez. It was sunny, breezy, the temperature was in the low 80s, and in general it couldn't have been more pleasant. We saw about half a dozen American Alligators, ALLIGATOR MISSISSIPPIENSIS, each sighting more spectacular than the last. You can see the last one at https://www.backyardnature.net/n/09/090316al.jpg.

That alligator is about eight feet long. I read that the average size for adult females is around ten feet and 200-250 pounds while adult males reach 13-15 feet and weigh 450-600 pounds, the record confirmed length being 19 feet, 2 inches long, caught in Louisiana. Still, most alligators seen around here are much smaller than the one in the picture. Karen has been around them all her life but had never encountered one that big. When we spotted this one, Karen began reconsidering her plan to return and fish in that spot.

I read that you can't determine an alligator's gender without inserting fingers in places I have no interest in exploring. The individual in the picture had his mouth closed nearly the whole time I was there so I'm pretty sure he opened his mouth to threaten me. Also, alligators inflate their bodies as part of their threatening behavior, so I suspect that much of what looks like a very well-fed alligator body is air.

At https://www.backyardnature.net/n/09/090316am.jpg you can see two smaller alligators we'd met earlier. We watched as the two gators approached one another on a direct collision path. When they got about six feet apart they both stopped and just waited. Finally the closest one, a little smaller than the other, turned to the side and let the bigger proceed in his straight line.

Back to those open jaws: I read that humans can bite with a force ranging from 55-200 pounds. Lions can bite with a force of 940 pounds, and a 12-foot alligator can bite with a force of 2,125 pounds!

A University of Florida web page provides a lot more alligator information, pictures and references at http://www.flmnh.ufl.edu/cnhc/csp_amis.htm.

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"MUDBUGS"
Upland Mexico is regarded as the center of oak-tree evolution, evidenced by the large number of species present there. In the same way, the US Southeast appears to be the center of evolution for crayfish. Mississippi itself is home to about 63 species of which at least 17 are endemic. About ten Mississippi species are known but not yet given names by experts. With so many species to choose from I had no idea what might be the name of the inch-long one shown at https://www.backyardnature.net/n/09/090316cr.jpg.

Dr. Susan Adams at the USDA Forest Service Southern Research Station in Oxford, MS is a crayfish expert and she identified the picture as a PROCAMBARUS of some sort. Procambarus is the largest of Mississippi's seven crayfish genera.

The above picture was taken in a mudhole half filled with water. As I sat waiting for the frogs who had jumped into the water as I approached to reappear, the mud beside me began working as many little crayfish just like the one in the picture began emerging -- not from holes in the mud but from the mud's flat, gravy- like surface. It's hard to imagine a muddier, gummier, seemingly suffocating world, but those little critters appeared very much at home. Footprints of a large heron, probably a Great Blue, crisscrossed the mud and I visualized the bird casually stalking across the mud probing here and there with his long beak.

A few feet from the mudhole rose the mud chimney shown at https://www.backyardnature.net/n/09/090316ch.jpg.

That chimney is much too large to have been built by a crayfish as small as the one photographed, and I don't know whether the crayfish in the picture is the adult of a small species or the juvenile of a species that gets bigger. The chimney was about ten inches high and you can see that its top was darkly moist, apparently having been placed there the previous night. The lower part is older and therefore more dried out and paler. Sometimes mud chimneys display variously colored mud layers because as the crayfish digs deeper different colored soil is passed through. Crayfish dig up to three feet deep and more. Sometimes a chimney rises above a single burrow that goes straight down but more often the main tunnel has a couple of side tunnels, each with a room at the end. Often you can look down a chimney and see water, for crayfish are aquatic, absorbing oxygen through interior gills.

In Mississippi some people call crayfish "mudbugs." As a kid in rural Kentucky I was taught to call them "crawdads," and we thought only people trying to act smarter than they really were used the name "crayfish." That word "crayfish," however, has honest roots. It's thought that it arose in English around 1400 from the Old French word "crevice."

The US Forest Service hosts a very nice "Mississippi Crayfishes" page produced by Dr. Adams in Oxford at http://maps.fs.fed.us/crayfish/.

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A TITMOUSE MEAL
The other day a Tufted Titmouse, BAEOLOPHUS BICOLOR, landed atop a trellis not far from me. Carrying in his beak half a Water Oak nut too large to swallow whole he looked right and left, then wedged the seed between his feet and began chiseling at it with his small, sharp beak. Pictures showing the whole operation are at https://www.backyardnature.net/n/09/090316tt.jpg.

Stabilizing food between the feet like that and pounding on it straight up and down with the beak is a behavior shared with other titmouse and even chickadee species. The assumption is that the behavior arose in an ancestor common to both titmice and chickadees, and the genetic predisposition to do so was retained as new species arose from the ancestor. Members of the Jay Family do the same thing, the behavior probably having arisen independently in both groups.

Nowadays titmice around here certainly are full of hormones. You see couples cavorting and mating up in the trees, at least I suppose that that's what they're doing as they lock together and tumble downward fluttering and squeaking like fighting cats. The other day a pair almost ran into me coming around the corner of the house, one holding a feather. At dawn, calling males are prominently represented in the "morning chorus" of birds who begin singing well before it's light enough to see anything larger than a toad.

If you'd like to hear what I hear every morning, a plaintive peter-peter-peter, click here, then click in the MULTIMEDIA box.

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A PINE WARBLER'S TAIL
This week another small bird landed on the ground nearby just long enough for me to snap the picture at https://www.backyardnature.net/n/09/090316pi.jpg.

With its size and slender, insect-eating beak it's clearly a warbler, but it sure is nondescript. Even having the picture on my computer screen I had to work awhile to be sure it was a first-winter Pine Warbler, DENDROICA PINUS, a permanent resident throughout the Southeast's pine zone. During summers Pine Warblers migrate northward throughout the eastern US and southeastern Canada. Since most other warbler species here are present only during the summer, that made it easier to figure out I had the permanent-resident Pine Warbler.

The main other species it could have been at this time of year was a nonbreeding Yellow-rumped Warbler. The main features convincing me that it was a Pine were the relatively long tail and relatively thick beak. Pine Warblers are common here but typically they stay high in the pines where you don't notice these subtle differences. The breeding male is bright yellow and easy to identify.

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RACERS HAVE EMERGED
I didn't realize I'd stepped on or come close to stepping on the poor snake until he began writhing in dry leaves below me. By the time I realized it was a snake I was already airborne well beyond striking distance, even though a glimpse told me it wasn't a venomous species. It was a Southern Black Racer, COLUBER CONSTRICTOR ssp. PRIAPUS, and you can see him at https://www.backyardnature.net/n/09/090316sn.jpg.

Racers aren't venomous but they do aggressively defend themselves. I toyed with the idea of holding his head down with a stick as I grabbed him behind the neck for a close-up, but he'd have nothing of that, striking at the stick before I could get it near him. I just let him lie, which I should have done from the beginning.

One feature making this a racer instead of, say, a rat snake, is its smooth scales. Scales on rat snakes display a very narrow, low ridge running lengthwise, and are said to be "weakly keeled." You can see that this racer's diamond-shaped scales don't have a hint of a keel. Also, racers are slender, as snakes go.

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PEARL CRESCENT ON A LEVEE
Several butterfly species have emerged here, most notably yellow sulfurs, white whites, and big, yellow- and-black Tiger Swallows. At St. Catharine NWR as we hiked down a grassy levee with water on both sides another famously early-emerging and conspicuous species took special interest in us. He'd land just ahead of us as we walked, then flit a little farther as we drew near, again and again. You can see him at https://www.backyardnature.net/n/09/090316pc.jpg.

That's the Pearl Crescent, PHYCIODES THAROS, occurring from the Yukon south to southern Mexico, except for the US West Coast. With such a vast distribution area we can guess that there's a lot of variability in the species' appearance, or phenotype. That's true, especially with regard to the wings' black markings, some individuals being overall much darker than ours, some much less.

One constant throughout the species, however, is its "extrovert behavior," sometimes interpreted as curiosity, sometimes pugnaciousness, and sometimes pure recklessness. Writing from the Kentucky Bluegrass Region in 2006 I described Pearl Crescents as my "most common window-knocking species" -- the butterfly most likely to enter through the old farmhouse's broken-out windows, then knock against other window panes trying to get back out. They kept me busy shuttling them back outside. " ...often I just put a finger before them and more than likely they'll stick out their proboscises, discover how nicely salty my fingertip is, climb onto it as they sup, and ride it as I walk outside."

I read that Pearl Crescents lay their eggs on aster leaves, which its caterpillars later eat. The species' main habitats are moist meadows, fields, roadsides, streamsides and open places like our grassy levee.

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BIRD-DROPPING MOTH
Much less eye-catching but maybe more interesting was a little fellow who also showed unusual "curiosity" about us as we hiked down that same levee, shown at https://www.backyardnature.net/n/09/090316bd.jpg.

That's the Exposed Bird-dropping Moth, ACONTIA APRICA, a member of the Owlet Moth Family, the Noctuidae. I'd never have been able to identify this moth without guessing that any English name it might have would need to include the words "bird-dropping," because of the moth's resemblance to that useful stuff. By doing an image search on the keywords "bird dropping moth" I soon came up with a match.

Plenty of images of the species occur on the Internet, for it's distributed throughout most of the US. However, there's little lifecycle information, other than a note from Covell's Field Guide to The Moths of Eastern N. America that its larvae feed on Hollyhocks. In the refuge I saw no Hollyhocks but the levee was littered with dead stems of many closely related Swamp Rose-Mallows of the genus Hibiscus -- thus in the same plant family as Hollyhocks -- so probably the larvae eat hibiscuses, too. Maybe the adult in the picture had just emerged from a dead hibiscus stem where it had overwintered.

I have no idea what is so "exposed" about the Exposed Bird-dropping Moth. Something not showing well in the photo is that individual white scales in the wings' rear, dark regions sparkle in bright sunlight, as if the dropping were recently deposited.

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TULIPS BLOSSOMING
This week Karen's tulips put on a show, as can be seen at https://www.backyardnature.net/n/09/090316tu.jpg.

On Public Radio I've heard how when tulips were introduced into China the emperor was so pleased that he had a special song written in their praise. I understand why someone seeing a tulip for the first time might want to celebrate in song. Few blossoms combine simplicity and gorgeousness so effectively.

Over 3,000 different registered varieties of cultivated tulips are recognized. The tulip genus TULIPA exists in the wild from the Mediterranean region across Asia to Japan. The commonest garden tulips are derived from just two species, T. gesneriana and T. suaveolens, though other species are often grown as "botanical tulips." The Royal Horticultural Association of Holland has grouped tulip varieties into official divisions. An illustrated chart representing the main ones can be accessed at http://www.theplantexpert.com/springbulbs/TulipIntro.html.

At https://www.backyardnature.net/n/09/090316tv.jpg there's a close-up of a tulip's sexual parts. The white centerpiece is the female pistil consisting of stigma (the 3-armed top), style (neck beneath the stigma) and ovary (most of the bottom part). The elongate, black items radiating from the white pistil's base are male, pollen-filled anthers.

Within the huge Lily Family the genus Tulipa is distinguished by its plants emerging from bulbs, its individual leaves arising directly from the bulbs instead of from leafy stems, the "petals" (actually sections of the fused calyx and corolla called a perianth) are separated from one another at their bases, and there are no nectar-producing nectaries.

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SWAMP-PRIVET FLOWERING
In the Refuge at the water's edge the most brightly flowering shrub or small tree is shown -- with an alligator in the canal behind and to the left -- at https://www.backyardnature.net/n/09/090316fr.jpg.

That's the Swamp-Privet, FORESTIERA ACUMINATA, a shrub native to the Southeastern and South-Central US. A close-up of some of its male flowers (the plant being monoecious, with individual flowers either male or female, but both sexes found on the same plant) with four yellow, petal-like sepals below many stamens is at https://www.backyardnature.net/n/09/090316fs.jpg.

Swamp-Privets are members of the Olive Family, the Oleaceae, along with privets, lilacs, Forsythia and ash trees.

The book Native American Ethnobotany By Daniel E. Moerman (available online through Google Books; Google the title) reports that the Houma people of southern Louisiana traditionally used a decoction of Swamp-Privet roots and bark as a "health beverage" panacea.

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BLACK WILLOWS FLOWERING
The refuge's most abundantly flowering tree species was certainly the Black Willow, SALIX NIGRA. In waterlogged soils Black Willow formed pure stands and the trees were loaded with flowers. Since willows come in male and female trees (they're "dioecious") we always knew which sex we were passing by, for the flower clusters look very different.

At https://www.backyardnature.net/n/09/090316w1.jpg you see a male tree's yellow, finger-length catkins composed of many male flowers consisting of clusters of pollen-producing stamens.

At https://www.backyardnature.net/n/09/090316w2.jpg female catkins show up as greener, more compact items consisting of many packed-together pistils. The flattish, whitish things atop each pistil are stigmas -- the place where pollen grains are supposed to land and germinate. Pistils consist of stigma, style and ovary, and mature into fruits, which in the willows' case are dry capsules.

Five willow species are listed for Mississippi. Flowering Black Willows are distinguished by each male flower having three to five stamens instead of one or two, which is more common in the genus. Also, Black Willow's male flowers occur in whorls along the slender inflorescence axis instead of spirally (you can see the whorls in the above picture of male flowers, especially on the pale catkin in the lower left). Black Willow's leaves also are dark green on both sides, instead of having much paler undersurfaces, which many willow species have.

Maybe one reason large parts of the Refuge are occupied with very dense Black Willow thickets is that almost all willows take root from broken branches that fall onto the ground, and Black Willow stems are somewhat brittle. When I was a tree-planting kid on the farm in Kentucky my father warned me many times not to plant willows around the house because their roots grew far from the tree and formed masses of interlacing roots wherever they found water, as in our water well, plus they could enter water pipes not perfectly sealed and clog them. In Nature the willows' dense root networks protect stream banks from erosion.

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LOTS OF POLLEN IN THE AIR
You might think that so many Black Willows flowering in the Refuge might explain what's shown at https://www.backyardnature.net/n/09/090316ye.jpg.

That's a yellow line of pollen left by retreating water at the edge of a flooded field where wind had deposited unimaginable quantities of pollen atop the water.

The problem with that assumption is that willows are mainly insect pollinated; their pollen is too large and gummy to be carried far by wind.

The pollen in the picture probably derives from a variety of sources. In the uplands a mile and more to the east of the photo nowadays people's cars are blotched yellow from daily showers of Loblolly Pine pollen, and their windshield wipers are strung with fallen catkins of male oak flowers.

Oak pollen is indeed wind dispersed but pine pollen is heavier and doesn't travel quite so far, so maybe there's not as much pine pollen in the picture as you might expect.

Knowing which tree species produce light, airborne pollen is a good idea for those with pollen allergies. At http://www.allergyescape.com/Pollen-Allergy.html you find lists of the main tree species causing allergy problems in different parts of the US. In the US Southeast, oak, walnut, birch, elm, cottonwood and pecan are the main culprits, pines being conspicuously absent from all lists, despite the profuse, conspicuous amount of pollen they generate.

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A STRANGE AND BEAUTIFUL ENVIRONMENT
In the Refuge, Karen and I hiked several miles down a seldom-used ATV trail through the bottomland forest adjacent to the Homochitto River. You can see Karen on the trail through that unusual environment at https://www.backyardnature.net/n/09/090316kw.jpg.

Mile after mile the forest floor we passed over was brilliant with flowerings of the yellow-blossomed wildflower seen in that picture. The plant is Butterweed, PACKERA GLABELLA, profiled in the recent March 2 Newsletter, and with its own page at https://www.backyardnature.net/n/h/packera.htm.

Seldom does one wildflower species so completely dominating an ecological niche over such a large area. Surely it's because Butterweed's adaptations enable it to survive in a very unstable environment -- unstable because often these bottomlands are flooded beneath several feet of water, and the flooding comes at different times of the year. Some years they'd be flooded now. When snow and ice up north start melting and spring rains kick in, they may flood again in a few weeks.

Whatever their germination biology, for us Butterweed created an ephemeral, enchanted community we felt honored to walk through. This was not only because of the flowers' brilliant color but also because of their sweet perfume. You don't think of Butterweed flowers as being particularly sweet smelling, but when there are millions and millions of them, the odor is intoxicating.

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ORANGE SLIME UPDATE
Last week I asked if anyone had thoughts about what the orange slime was below the bleeding grapevine at https://www.backyardnature.net/n/09/090309of.jpg.

Several folks responded, reminding me that some enormously informed, experienced and talented people out there subscribe to this Newsletter. If I think about that much, it scares me...

Pam in Colorado sent me a link to a technical journal reporting on similar orange growth on grapevines in Ontario. Pam writes: "The author, Wendy McFadden-Smith, did cultures and found several fungal species combined with yeast. She speculates the sap from pruning wounds was an ideal growth medium for these organisms, not harmful to the plant."

Sherman in Mississippi, a retired pathologist who has seen something similar at his tree farm, wrote "I have no doubt that it is a myxomycete, so your diagnosis is correct. It's been some time since I studied this organism, but if I remember correctly I identified a flagellate phase and an ameboid phase." So Sherman had identified a plasmodial slime mold. I'm waiting to find a slime mold I'm sure about before talking about it, for slime molds are mind-bogglingly fascinating and mysterious organisms.

I can't be sure that what's in the photo is what either Pam's expert or Sherman are talking about, but it's fascinating that with all our combined brainpower we still can't be sure what's in the picture. There's still a lot out in the world to figure out and wonder about. Thanks to everyone for the input.

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ON BEING A NOTE OF MUSIC
Last Wednesday night I awoke just busting to go pee. Outside, the almost-full moon etched the pines against a cold, starry, crystalline sky but what really impressed me was how good it felt to get my business done. Back inside the trailer, my nose at the open window, it was cozy lying toasty inside my sleeping bag, breathing in the night's cold, fresh air.

Lying there, I got to thinking about all the ways our animal bodies reward us when we do what we have to do. It feels good to have a good pee and it feels good when you've taken care of your body so that it's fit and functions well. From there, my thoughts ranged to how good it used to feel to be surrounded by family and people I'd known since birth, and then I thought about all the positive reinforcement one gets automatically when a certain respectable status is achieved among coworkers, and I even remembered how comfortable it had felt when I'd had a socially acceptable job and bought lots of books, a stereo system and a car.

In fact, that night luxuriating inside the sleeping bag, for awhile I began regretting that somewhere along the line I'd decided that I needed more than to go through life fulfilling the biologically and socially programmed obligations that beckoned me when "I" crystallized inside an animal body on a farm in Kentucky in 1947. How pleasant it might have been if during my whole life my living strategy had been simply to do what my body and various forms of programming had required of me.

Then as a kind of thought experiment I began trying to imagine what existence might be like if all my bodily needs and genetic and social programming somehow were stripped away. What would be left? Would there be anything worth staying alive for?

There'd be music. It feels good hearing a simple melody artfully recapitulated and ornamented in a Bach fugue. And beyond that it feels very good in a spiritual sense understanding that the Creator of the Universe Herself is a musician and the Universe is the Creator's fugue, and that I'm a note in one of Her melodies.

I didn't get further than that. I fell into a fine sleep, something we beings inside animal bodies are subject to. And the next morning I awoke to the birds' morning chorus, jogged along the gravel road, and got my campfire going. And how good were the steamy tea and the campfire's warm glow on my face and arms.

And what a majestic work of art it is when you can be a note in a melody -- and know that you are such a note -- just by sitting next to a cheery campfire, sipping tea after a good night of sleep.

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Best wishes to all Newsletter subscribers,

Jim