March 23, 2009
SAVANNAH SPARROW APPROACHABILITY
At St. Catharine National Wildlife Refuge just south of Natchez this week I was way out on a levee barely rising above vast, silvery-surfaced, flooded fields on both sides of me. I was the most conspicuous feature on the landscape for miles around, so maybe that's why a certain little sparrow came to run and hop along the water's edge beside me as I hiked down the levee.
When I stopped he stopped and when I went on he continued running beside me, about ten feet away. His breast was so heavily striped that at first I thought he was the common Song Sparrow, who overwinters here, but I'd never seen a Song Sparrow behave like this. Once I got my camera focused, immediately I saw the yellow eyebrow, and I knew he was a Savannah Sparrow, PASSERCULUS SANDWICHENSIS. You can see him at https://www.backyardnature.net/n/09/090323ss.jpg.
In that picture mud on his beak distorts the beak's apparent shape. Mudless, his beak is short and pointed the way a sparrow beak is supposed to be.
Savannah Sparrows are one of those species you don't usually see if you don't visit some fairly wild habitats; I've not seen them beneath birdfeeders or in the suburbs. However, they're fairly common birds in open country, the field guide mentioning hay meadows, marshes and tundra. They overwinter throughout the southern US south to Honduras and nest throughout northern North America from the highest Arctic south to about Utah and Illinois. In the east they seem to be declining in numbers, supposedly because of the trend for abandoned open farmland to revert to forest, but in the west they'e enjoying a slight population increase because of increasing deforestation and intensive agriculture.
The Smithsonian Field Guide applies the interesting adjective "approachable" when describing this species. This makes me believe that I'm not the only birder who has been astonished by the bird's apparent attraction to, or at least tolerance for, roving humans.
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SNOW-BIRD VARIATIONS
At https://www.backyardnature.net/n/09/090323ju.jpg you see a Dark-eyed Junco, JUNCO HYEMALIS, with a plumage unlike any illustrated among the new Smithsonian field guide's eight photos, which mean to emphasize how variable the Dark-eyed Junco's plumage can be. The junco in the picture is one of several coming daily to peck in the gravel parking area outside Karen's window where occasionally she tosses birdseed just for them.
Among the little flock of maybe half a dozen birds not one individual looks exactly like any of the rest. In the old days field guides called them Slate-colored Juncos and certain plumage variations were recognized as distinct species, such as the "Oregon Junco," but nowadays they're mostly lumped into one "polymorphic" species. The Yellow-eyed Juncos we've seen in Mexico's highlands remain a distinct species, however. A "classic junco" and several variations are shown at http://sdakotabirds.com/species/dark_eyed_junco_info.htm.
As a child I was taught to call juncos Snow Birds, and it's true that usually I didn't notice them except during unusual Kentucky snows when they'd come in from fallow soybean fields and feed on the ground beneath our birdfeeders. As in Kentucky and here, in most of the US Dark-eyed Juncos are only winter visitors, permanent breeding populations being restricted to higher elevations, New England and the Pacific Coast. During the summer nesting season the population shifts northward to include Canada and Alaska.
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MOURNING DOVE'S POINTED TAIL
Right after snapping the above junco picture a Mourning Dove, ZENAIDA MACROURA, sailed down next to me, so the resulting picture is at https://www.backyardnature.net/n/09/090323zn.jpg.
Mourning Doves are among the best-known North American birds, nesting in most of the US and Mexico, and during the summer migrating deep into Canada. They even turn up below birdfeeders in small towns and the suburbs. My field guide says they're absent only from extensively forested landscapes.
There's a lot of folksy discussion about Mourning Dove courtship behavior, nesting, eggs, young, plumages, food and more in the online AC Bent electronic book at http://www.birdsbybent.com/ch11-20/mourning.html.
Of the 12 North American pigeon and dove species profiled in the Smithsonian field guide, only the Mourning Dove has such a long, sharply pointed tail.
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RED-EARED TURTLES COMING ASHORE
In St. Catharine NWR I lost count of the number of Red-eared Turtles, or Sliders, TRACHEMYS SCRIPTA, seen emerging from water and scrambling to higher ground, often with me not far away and moving. Typically our basking Red-ears slide off their perch into the water as soon as they see you within rifle-shot distance, and for good reason. I read that egg-laying is from May through early July, but often such pronouncements are made by specialists living much farther north, so I can't discount the idea that these Red-ears were looking for someplace to lay eggs. You can see one hastily emerging onto a levee at https://www.backyardnature.net/n/09/090323re.jpg.
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WHITE-FOOTED MOUSE IN A BAG
When a certain thumping followed by furious scratching of tiny paws arose from inside a paper bag behind my computering spot in Karen's laundry room I knew instantly what it was, for during my hermit years near here I'd heard the sound a thousand times: a snoopy, adventurous, hungry White-footed Mouse, PEROMYSCUS LEUCOPUS, had gotten himself into a hard place to get out of and was trying to jump out, again and again. When it happens in the middle of the night in a tiny trailer, your brotherly feeling toward other animals is sorely tested. You can see the bag-imprisoned individual interrupting my meditations the other day, at https://www.backyardnature.net/n/09/090323wm.jpg.
White-footed Mice must be among the most successful of all mammals. By successful I mean that they enjoy a large distribution, from Nova Scotia and Saskatchewan south through most of the eastern US, and down through eastern Mexico all the way to the Yucatán. Around here I think every brushpile, every woods edge, every acre of woodland disrupted by logging, every shed, every abandoned car and most houses at least occasionally host White-footed Mice.
Back in my hermit days I invested a lot of time trying to catch them without hurting them. My most successful trap consisting of placing a foot ruler delicately balanced so that nearly half of it extended beyond my table's top, to out over a bucket below. At the end of the ruler jutting into space I'd leave a cornbread crumb. The bucket needed about half an inch of water in it. Nearly always, soon as it was dark, the ruler and a mouse would tumble into the bucket, awakening me. Then I'd carry the mouse outside and coax him into a container so I could carry him a mile or so away during the next morning's jog. The water in the bucket was necessary because a dry White-footed Mouse can jump unbelievable heights but a wet mouse can't jump over a bucket's rim. You don't want it deep enough for him to drown, though.
Despite my many jogs carrying mice a mile from my trailer, I never seemed to reduce the mouse population. Now I learn that in experiments in which White-footed Mice were captured and let go two miles away the mice found their way back home. This and much more information on the species' behavior is available here.
Actually, there's another almost identical but slightly larger mouse in this area, the Cotton Mouse, Peromyscus gossypinus, which I can't differentiate without precise measurements and weighing. I'm just guessing that that's a White-footed Mouse in the bag because of the White-footed's general fame as one of the commonest of all small mammals wherever it occurs. In other words, "White-footed" is the best educated bet.
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A CLASSIC BEAVER DAM
Recently we looked at a beaver lodge. This week in the Refuge I ran across a classic beaver dam, shown at https://www.backyardnature.net/n/09/090323bv.jpg.
Notice how pooled water on the high, nearer side is muddy while water below the dam looks a bit clearer. Here the dam is fulfilling one of its services to the ecosystem by slowing water down causing eroded soil particles suspended in the water to settle out. The dam thus keeps eroded soil from continuing into rivers downstream. If the dam is permitted to remain, eventually a species-rich "beaver meadow" or marsh will form above the dam.
The Beaver Dam Information Site provides loads of info about beaver dams at http://www.beaverdam.info/.
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BLACK CHERRY TREES FLOWERING
When I passed through here last June I photographed cherries on the Black Cherry tree, PRUNUS SEROTINA, next to my trailer. You can see that summery picture at https://www.backyardnature.net/n/08/080616bc.jpg.
This week the same tree has been full of flowers, setting the stage for June, 2009 cherries. You can see flowers and leaves on the same branch as above at https://www.backyardnature.net/n/09/090323bc.jpg.
At https://www.backyardnature.net/n/09/090323bd.jpg you see a single flower in the panicle of flowers shown above. What an elegant little blossom it is, its five white petals affixed so geometrically around the rim of the cuplike hypanthium, male stamens also arising from the rim, alternately bending toward the flower's center or leaning away from it, and in the center of the hypanthium cup the pale, irregularly shaped thing is the stigma atop the female pistil. Below the stigma lies the green ovary, which later will mature into the cherry.
That cuplike hypanthium is worth fixing in your mind because it's so typical of many genera in the huge Rose Family to which Black Cherry trees belong. Recently we've seen hypanthia in plum flowers, also members of the Rose Family. Most flowers have stamens and petals attached at the base of the pistil, not from the hypanthium's rim, and with nothing like the hypanthium, which is like a little bowl holding a single cherry inside it.
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THE PEACH BLOSSOM'S FUZZY OVARY
At https://www.backyardnature.net/n/09/090323pf.jpg you see two typical peach-tree blossoms displaying the expected five pink petals and numerous male, pollen- producing stamens. A cross section of a flower is at https://www.backyardnature.net/n/09/090323pg.jpg.
Peach trees belong to the same genus as the above Black Cherry tree -- Peaches are PRUNUS PERSICA -- so they're very closely related and their basic flower designs are very similar. Note the Peach flower's cuplike hypanthium with stamens, petals and sepals arising from the cup's rim. See how the female pistil sits inside the hypanthium, and how the hypanthium arises below the pistil?
You can't miss how hairy the ovary is, the ovary being the pale, oval item at the base of the pistil. That ovary is the future peach fruit, and the hairiness on the ovary is future peach fuzz.
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BLACK OAK'S FUTURE ACORNS
Black Oaks, QUERCUS VELUTINA, are common here and these days show up on the landscape as big, silvery- green bouquets. The silveriness is caused by short, branched, white hairs densely mantling expanding leaves and stems. On individual Black Oaks whose yellow, dangling, wormlike clusters of male flowers, or aments, already have released their pollen and are falling off, now you can spot later-blooming female flowers, which will mature into acorns next year. You can see a Black Oak's future acorns at https://www.backyardnature.net/n/09/090323ok.jpg.
In that picture the stem, newly emerged from a twig's terminal bud, is the "floor" in the lower left corner. The thing paralleling the picture's right side is a leaf petiole, and in the image's center rise two female flowers -- the future acorns -- on a short stem, or peduncle. Atop the peduncle are three female flowers, two with their black, 3-lobed stigmas deployed, ready to receive pollen. Despite the dense fuzz investing the flowers you can barely make out blunt, brown scales surrounding the oval pistil (comprising stigma, style and ovary). Later those scales will enlarge, harden and become scales on the cup below the nut. The nut will derive from the pistil.
The fact that this particular tree's aments of male flowers already have fallen off keeps down self-pollination. Other Black Oaks in the community still bear male flowers, however -- their female flowers not yet matured -- so there's still plenty of Black-Oak pollen in the air for the female flowers in the picture.
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A HICKORY'S UNFURLING LEAVES
At https://www.backyardnature.net/n/09/090323hi.jpg one of our pignut hickories, the CARYA GLABRA-OVALIS complex, is shown unfurling its compound leaves. Each leaf bears five or seven leaflets. A pretty thing that hickories do when spring's leaf-bearing stems emerge from a twig's terminal buds like this is that the former buds' inner scales enlarge tremendously, becoming fleshy and colored. You can see such pink, inner scales in the picture curling back at the base of the vertical new stem. There's a special botanical word describing things that enlarge after flowering or after something has emerged from its bud, and that's "accrescent." A hickory's inner bud scales are beautifully accrescent.
This pignut hickory's accrescent inner bud scales are about two inches long. Hickories with heavier stems and bigger buds, such as Shagbarks and Mockernuts, produce even larger overwintering buds with accrescent inner bud scales growing well over three inches long.
Of what use are a hickory's accrescent inner bud scales? I'm guessing that they might distract caterpillars climbing their stems looking for succulent leaves by offering fleshy meals of non- photosynthesizing and thus non-critical tissue, but that's only a guess.
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ELEGANT WATER-STARWORTS
Back in St. Catharine NWR, in clear pools of permanent water here and there you can find very interesting aquatic plants rooted in the mud. One of them is shown at https://www.backyardnature.net/n/09/090323sw.jpg.
That's a Water-Starwort, CALLITRICHE HETEROPHYLLA. In the picture, green rosettes floating atop the water's surface top vertical stems attaching to horizontal runners rooted in mud about ten inches below the water's surface. You can see that the plant's surface leaves have a different shape and color from those on submerged stems.
Native throughout North America and Mexico, this is one of those species with an enormous distribution, but in any particular place shows up only here and there. My impression is that it needs fairly unpolluted, undisturbed aquatic habitats, and of course such wetlands have suffered drastic loses. Though some authorities describe this as a common species, it's listed as threatened in Michigan and Wisconsin. It's a small plant, the larger leaves only about an inch long and the stems below the rosettes up to about a foot long. Water-Starworts are flowering plants, but the flowers and fruits are small, submersed and seldom noticed.
When you find pagodalike water-starworts rising through clear water populated with all kinds of microscopic aquatic invertebrates showing up brilliantly in intense sunlight, you're charmed by the three-dimensionality and liveliness of the scene. You wish you could be like water fleas and paramecia diving and soaring through the water like shooting stars. Few environments fill one with a sense of Nature being so healthily and beautifully Herself as clear-watered aquatic ones, and delicate little water-starworts are perfect citizens of that magical place.
The stems and fruits of starworts are grazed by ducks and other waterfowl. The branching stems provide shelter and forage to fish.
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CEDAR-APPLE RUST
A couple of weekends ago we had several days of showers and storms, which much encouraged the Kingdom of the Fungi. One of the most interesting fungi to appear soon after the rains ended was GYMNOSPORANGIUM JUNIPERI-VIRGINIANAE, Cedar-Apple Rust. Its picture is at https://www.backyardnature.net/n/09/090323gj.jpg.
At least, that picture shows one of Cedar-Apple Rust's manifestations. This fungus has a complex life history and what you're seeing is the way it looks growing on a stem of Eastern Redcedar, Juniperus virginiana. Here's the rest of the story:
Cedar-Apple Rust alternates between Eastern Red Cedar and, usually, apple and crabapple. After spring rains the bright orange, gelatinous masses of spores shown in the photograph (technically known as telial horns) emerge from hard, spherical stem galls where the fungus has overwintered. When dry weather comes a few days later the masses disintegrate into loose spores (special spores known as teliospores) that wind blows onto apple and crabapple trees whose stems and leaves are just emerging from buds.
Inside growing apple and crabapple leaves two strains of the fungus mate and produce structures on the lower leaf surface from which a new spore form is realeased. These spores are then blown back to redcedars in mid summer to fall, develop galls on a redcedar that mature over a period of about 17 months, and then after spring rains the next year the whole cycle begins again. Wind can easily spread spores between redcedars and apple and crabapples for distances of several hundred yards, and if a spore is particularly lucky, even miles away.
You can see the galls the orange horns emerge from here.
Pictures of infected apple leaves are shown here.
The life cycle is explained in more detail, and advice given on protecting apple trees from the disease, here.
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INTO A BUBBLE OF CALMNESS
Into the bubble of calmness around my morning campfire a two-inch long, reddish and pale orange, thumb-shaped blossom fell onto the leaf litter beneath the big Black Oak beside the trailer. It was so quiet that the flower's soft thud could be heard. Maggie the Dog, lying a couple of yards away, heard it hit and went over sniffing where the sound had come from. All she could find out of the ordinary was the blossom, so she sniffed it circumspectly, but didn't bother to pick it up. She looked at me and I was noncommittal, so she just walked away, her face suggesting that it'd been worth her effort if only because at least she'd discovered an interesting new odor.
After breakfast I smelled for myself. The odor reminded me of Worcestershire sauce, but I know that vegetarian noses smell things differently from noses of flesh eaters. Then I took the picture shown at https://www.backyardnature.net/n/09/090323cv.jpg.
I'd known instantly what plant had dropped the flower, for often I've admired its blossoms. The flower had fallen from a native woody vine that climbs high into trees bearing clusters of 2-5 blossoms in arrangements very pretty to look at. The vine is called Crossvine, BIGNONIA CAPREOLATA, and it's a member of the Bignonia Family, which explains why the flower's general form is like those of Trumpet Creepers and Catalpa trees, members of the same family.
The whole blossom-falling experience struck a certain chord in me, so I wrote a haiku:
A lone flower falls
into our pool of quietness.
I don't find the source.
Syllables of 5:7:5, capture the moment, let what's unsaid speak most powerfully... Why were we so quiet? Did I not find the source vine because it bore its flowers so high up, or because I didn't look? In either case, why or why not? Are we commenting on a subtle gesture by Nature, or on my own state of mind? In either case, so what?
All week loggers have ravaged the already overcut woods next to us: Noise of chainsaws and toppling trees from dawn to dusk. All week obsessive news reporting on the economy, but not a word about living things' need for clean air and water, healthy soil, and living space, and though the intricacies of money-exchange have been explored ad nauseam, no one talked about Nature's myriad planetary life-sustaining but collapsing networks and cycles. Noise and chatter, noise and chatter, and all saying the wrong things...
A lone flower falls
into our pool of quietness.
I don't find the source.
Anyone willing to share spring haikus is more than welcome to post them at our Backyard Nature Forum at http://groups.google.com/group/backyard-nature/.
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Best wishes to all Newsletter subscribers,
Jim
