July 28, 2008

WREN THUD
It's that time of year when one of the most agreeable things you can do is to sit on your porch with a pair of binoculars watching parent birds deal with their adolescent fledglings. I've never experienced raising human kids myself so maybe I have it all figured out wrong but what I see these days going on between bird parents and their kids strikes me as hilariously similar to what I witness among many human families with teenagers.

For example, a Bluejay parent with two fledglings hopped in the grass in front of my porch. The kids wore new blue, black and white feathers just like a grownup jay but you could tell they were adolescents because of their slender necks and their general demeanor. "Demeanor," as in standing gazing around sometimes halfheartedly foraging for food but mostly just looking very bored and displeased. But then the parent turned up something beneath a flipped-up leaf and instantly both young lost all composure, rushed to the parent, stooped and quivered their wings pitifully and cried AHH-AHH-AHH! The moment one of the kids got the grub in its belly both hopped away joyously to reassum their former stances.

Over at Pipes Lake a machinegun-like CH'K'K'K'K'K'K' erupted from a big adult Belted Kingfisher winging powerfully across the lake. Behind and below the parent a slightly smaller, paler kid followed strugglingly, fluttering more than sailing. At first the parent seemed to be heading into the inlet opposite me but at the last moment it veered into the next one. The kid wasn't paying attention and flapped heavily into the wrong inlet. A moment of silence followed. Then silently the high-flying parent emerged from its inlet, made a sharp U-turn into the inlet where the kid was, and in seconds out came out with the kid trailing below, the adult's CH'K'K'K'K'K'K' inflected in a way sounding more like cussing than birdcall.

Late each afternoon a parent Carolina Wren brings a kid to forage in the hedgerow next to my porch. The fledgling still has a few down feathers poking through its new primaries. One day when they came the parent landed inside the dense Poison Ivy climbing the big Black Oak. The kid followed but misjudged distances and simply crashed into the oak's trunk with a thud. The kid bounced, fell, held on by a single toenail, fluttered upright, took a big breath, looked around and gaped yawningly, and then parent and kid, without more ado, flew away together for more adventures.

And then there's the young Red-headed Woodpecker with his pale-brown head who usually comes alone in the afternoons, already a graduate from fledglinghood, apparently, to snoop among the pear trees. The pear trees now are heavy with almost-mature fruits and the dense pear clusters seem to attract the young woodpecker. In fact, that bird wedges his bill among the clusters and tears at them with his zygodactyl feet until one or more pears tumble to the ground. He doesn't peck on the pears, just seems to enjoy making them tumble. With kids like this, what's the woodpecker world coming to?

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A BAT'S TEETH AND TRAGUSES
The other day Karen noticed a little dark blob she hadn't noticed before wedged between the roof and some rafters. When she got real close she realized it was a bat, which delighted her. She came to get me, I got my camera, and you can see the resulting picture at https://www.backyardnature.net/n/08/080728bb.jpg.

One nice thing about that image is how well the teeth show up. Bat teeth I've seen before were sharp so I was surprised that this one's canines were so truncated. I'm guessing that this indicates an old bat. There's a nice page just on bat teeth at http://www.hastingsreserve.org/Mammals/Bats/ToothGap.html.

Another nice feature of the picture is that it shows the tragus. Among bats, traguses are leaflike structures arising in the exterior ear. Humans and other animals also have them, though not so well developed. A diagram showing where your tragus is at http://en.wikipedia.org/wiki/Tragus_(ear).

The function of bat traguses isn't clear, but it's assumed that they help with echolocation. What is certain is that in bat identification traguses are very important, for traguses come in different relative sizes and shapes, and they can be sharp or rounded at their tips.

To see our bat's tragus look at the base of the ear- hole in the picture's center. Notice the item similar to a fleshy shark fin with the top of the fin glossy and bent toward the bat's nose. That's the tragus.

Even with such a fine picture and a good view of our bat's blunt tragus I couldn't definitively identify our bat using my Peterson field guide to the mammals. Therefore I checked into the bat forum at http://www.batmanagement.com/cgi-bin/yabb2/YaBB.pl, posted my picture, and in a few hours bat expert John in Pennsylvania had posted a note that our bat, despite its small size, is the Big Brown Bat, EPTESICUS FUSCUS. That's a good species to know because it's one of the most widespread and common bats in North America, found throughout southern Canada and all of the US except most of Florida.

One bat-management professional on the Web writes that "99% of the bats that we remove from the living space of homes are Big Brown Bats."

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RED-HEADED BUSH CRICKETS
If your computer can handle WAV audio files and you live in the eastern US south of Chicago and New York, but not in southern Florida, the sound you can hear at http://buzz.ifas.ufl.edu/641ss.wav may be very familiar. It's one of the most typical insect calls emanating from unsprayed bushes and trees during the summer. However, if you try sneaking up on the caller it's almost guaranteed that it'll grow silent before you see anything, though other calls like it will continue, as persistent as the sounds of waves crashing at the beach.

At https://www.backyardnature.net/n/08/080728bc.jpg you can see what's making the sound. It's a bush cricket, PHYLLOPALPUS PULCHELLUS, sometimes known as the Red-headed Bush Cricket, Handsome Trig and other names. This one I spotted by chance, which is usually the way you see them, as I was scanning dense hedgerow vegetation next to my trailer looking for something else.

Though many web pages provide breakdowns of this insect's classification, it's hard to find such basic information on the species' life cycle, what it eats, when it starts singing, etc. This should encourage us all to put onto the web our nature observations, especially about lesser known species, so that anyone using a search engine well can eventually find it. This is one reason I set up our Backyard Nature Forum at http://groups.google.com/group/backyard-nature/.

For my part, here and now I contribute to the body of knowledge about Phyllopalpus pulchellus that in southwestern Mississippi in late July you can find the critter in bushes, but I don't hear them singing just yet. Maybe it's a bit early for them, or maybe my growing deafness is worse than I imagine.

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HEAD OF A SPECKLED KINGSNAKE
Speckled Kingsnakes, LAMPROPELTIS GETULUS ssp. HOLBROOKI, are among the most common and conspicuous snakes here. In the June 13, 2004 Newsletter at https://www.backyardnature.net/n/04/040613.htm I wrote about them. Despite already writing about them, when I ran across one this week glistening in bright sunlight along the road I decided to take a head-picture anyway, remembering how scale arrangement on a snake's head is so valuable during the identification process, and how hard it is to find good head pictures. You can see my resulting headshot at https://www.backyardnature.net/n/08/080728bk.jpg.

Speckled Kingsnakes are a subspecies of the Common Kingsnake. Where I grew up in western Kentucky our kingsnakes were plain shiny black, being members of the subspecies niger. The subspecies grade into one another, some individuals not clearly being one or the other.

It's interesting that back in Mexico Speckled Racers, not closely related but similar in overall appearance, also were often the most common and conspicuous species. My picture of a Speckled Racer in Querétaro is at https://www.backyardnature.net/n/07/070526sr.jpg.

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CHINKAPIN OAKS
At https://www.backyardnature.net/n/08/080728ch.jpg you can see the half-formed acorns and unusual leaves of the Chinkapin Oak, QUERCUS MUEHLENBERGII. The leaves of this species are unusual because of their coarsely serrate or toothed margins, with each serration capped by a sort of callus or gland, and the leaves' undersurfaces being silvery, much paler than the top surfaces. Chinkapin Oaks are fairly common here, though as a slow-growing oak the species is in general decline because "even-age" forest practices (clear-cutting) encourages fast-growing pine plantations to replace our former mixed forests.

Anyway, this is another of those species that just looking at its enlarging acorns and robust leaves fills me with pleasure. The medium-sized tree's bark is ashy gray, rough and flaky.

It's interesting that in the northern part of the Chinkapin Oak's distribution the species tends to grow on dry, rocky soil and limestone ridges. However, in the south they gather in deep valley with rich soils, so I've often wondered whether we might not have two species here. In southwestern Mississippi the thicker the ice-age loess deposits, the more Chinkapins you find.

That interesting word "chinkapin" is considered by etymologists as a probable modification of the Virginia Algonquian word chechinquamin, used to refer to the Chinkapin nut.

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CRAPE-MYRTLES FLOWERING
At this time of year towns in this area and little houses along roads are just resplendent with flowering Crape-Myrtles, LAGERSTROEMIA INDICA. You can see a portrait of a flowering Crape-Myrtle branch at https://www.backyardnature.net/n/08/080728cm.jpg.

If we accept that "myrtles" are members of the Myrtle Family, the Myrtacea, then Crape-Myrtles aren't myrtles because they belong to the Loosestrife Family, the Lythraceae. The Loosestrife Family is mostly a tropical American one, more or less recogniable by having two leaves at each stem node (they're opposite), and the flowers' calyx tubes bearing petals at their mouths. Crape-Myrtle flowers show this latter feature beautifully, for their frilly, ping-pong-paddle-shaped petals arise from atop the calyx tube (the hypanthium) on slender "handles," or claws, inserted between the calyx tube's triangular sepals. You can see this by looking at a flower from behind, as at https://www.backyardnature.net/n/08/080728co.jpg.

There's a frontal view of a flower showing the Crape- Myrtle flower's many (36-42) male stamens, at https://www.backyardnature.net/n/08/080728cn.jpg.

In that picture the yellow, oval objects are the stamens' baglike anthers splitting open and releasing pollen. The anthers are held aloft by slender, reddish filaments. You can see that some filaments are longer than others. Also, there's one long, slender, reddish thing in the picture without an anther atop it. It's the upward-curving, second-lowest filament-like thing. The reason it bears no anther is that it's the long neck of the female ovary, referred to as the style. Atop the style the blunt, rough-looking area is the stigma, where pollen grains germinate, send their pollen tubes like roots down through the style, to the greenish ovary unseen beneath the stamen bouquet.

Crape-Myrtles are originally from Asia. Among the reasons they're so common here is that they're tough plants easy to propagate. In early winter just cut off some switches about eight inches long and half an inch thick, stick them in containers of potting soil or well drained garden soil with about an inch of the cutting protruding above the soil line. Leave the pots outside, but protected from severe freezes. Once new growth emerges place the containers in a sunny place and keep watered until they can be set out.

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LEAF DOMATIA
Tufts of hair and other minute structures in vein axils on the undersurfaces of leaves are called domatia. Some leaves don't have them, some bear only poorly developed ones and sometimes domatia occur only on young leaves. However, in some species domatia are very well developed, as in the axils of major veins of a Sweetgum leaf found next to my porch and shown at https://www.backyardnature.net/n/08/080728ax.jpg.

A study in Australia found that leaves with domatia tend to support higher levels of predatory mites than leaves without them. Mites molt and lay their eggs in domatia and in return help defend the leaf against herbivores. Other tiny arthropods beside mites sometimes use them. In our area hairy domatia are particularly noticable on the undersurfaces of oak leaves. Especially in the tropics members of the Laurel Family have well developed domatia.

The word domatia (singular domatium) in Latin means "small house," and sometimes they do look like little houses, consisting of flap-like tissue projecting over the narrow angle between converging veins, just like a tiny roof.

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BEA'S ILLUSTRATED LIST
This week Bea in Ontario submitted her list of 66 plants and animals, with their Latin names, for my Silver Bug-Eaten Leaf Award. I'm awfully pleased that several awards have been given lately. Moreover, Bea's list has raised our list making to a new level because for each name on her list she's uploaded one of her own photos to one of several free picture-sharing websites! If you want to see what a particular species on her list looks like you just click on the name.

You can browse Bea's wonderful illustrated list at https://www.backyardnature.net/awards/s-can001.htm.

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INTERVEINAL CHLOROSIS IN A SWEETGUM LEAF
Trees here are still completely green as forests and fields photosynthesize at maximum efficiency. Still, the other day a yellowing Sweetgum leaf fluttered to the ground before me, and that set off a stream of thoughts. You can see the exact leaf at https://www.backyardnature.net/n/08/080728cl.jpg.

Because the leaf is yellow except for the greenness around its major veins it's clear that the leaf is suffering from interveinal chlorosis. Chlorosis is defined as a reduction of the amount of green pigment in a leaf. Since green plants photosynthesize their own food using the green pigment called chlorophyll, chlorosis is a serious ailment for any green plant. The worse the chlorosis, the less food the plant can manufacture for itself.

Back in plant physiology class I learned that in most cases when a plant's leaves uniformly lose their green color, the problem typically is lack of nitrogen. When yellowing leaves remain green along major veins, the problem usually is a deficiency of iron or manganese. Therefore, the Sweetgum tree from which my yellowing leaf fell surely was needing more iron and/or manganese in its soil.

Similarly, if a growing plant bears yellowing OLDER leaves but green NEW leaves, the plant probably suffers from nitrogen deficiency. If the growing plant has yellowing NEWER leaves but green OLD leaves, the deficiency is probably of iron and/or manganese.

The above sets of symptoms become understandable when we recognize this fact: In plant tissues, some elements are more easily transportable than others. Nitrogen is easily transported but iron and manganese are hard to move.

Therefore, if a growing plant finds itself short in nitrogen, it'll start borrowing nitrogen from old leaves, causing those leaves to yellow, and ship the borrowed nitrogen to its younger leaves, which will grown nice and green.

If the deficiency is in iron or manganese, however, the plant will find it hard to mobilize these elements in its old leaves. The new leaves will grow yellow while down in the old leaves the hard-to-move elements are clogging veins at their exit ramps, the big veins. At first the old leaves will look netted, yellow between green veins. Eventually the smaller veins also turn yellow as the elements move out. If the transfer continues, eventually parts of the leaf may start dying and the entire leaf will yellow.

If you have a plant showing interveinal chlorosis like my Sweetgum plant, the best long-term solution is to acidify the plant's soil, because the lower the soil pH, the easier it becomes for plants to transport hard-to-move elements like iron and manganese.

There's a helpful discussion on acidifying soil at http://hubcap.clemson.edu/~blpprt/lowerpH.html.

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WHERE ARE THE RAIN CROWS?
The other day Leona in Missouri wrote asking "does anybody note an absence of the Rain Crows (Cuckoo)? They aren't calling here, maybe because we have had more rain this season than any other time since we bought the place in 1975."

I also grew up calling Yellow-billed Cuckoos "Rain Crows." They don't look like crows but they do sonorously call KA KA KA KAW KAW KOW KOW KOWL KOWL... KOWLP.... KOWLP... from deep inside summer's biggest, most shadowy trees, especially before a good rain. Leona's question reminded me that I likewise have been hearing fewer Yellow-billed Cuckoos than I used to, so I wondered if they might be among the many songbird species suffering drastic declines.

"Populations of Yellow-billed Cuckoos have severely declined throughout their range, especially in western states, where they are now extirpated from British Columbia, Washington, and Oregon. As of 1999, the California population was down to 30 pairs," I read at http://birdweb.org/Birdweb/bird_details.aspx?id=239.

Habitat loss is assumed to be the main problem. Yellow-billed Cuckoos like dense vegetation. You can meet the Yellow-billed Cuckoo here.

The Audubon Society presents a list of North America's twenty most-in-decline bird species at http://stateofthebirds.audubon.org/cbid/browseSpecies.php.

Yellow-billed Cuckoos aren't on that list, but it's heart-breaking to see what species are. The species suffering the greatest decline since 1967 is the Northern Bobwhite, down 82%. Also Eastern Meadowlarks are down 72% and Whip-poor-wills are down 57%. All three species are ground nesters. Now that more marginal agricultural land will be planted to produce biofuels we can expect even greater declines for our ground dwellers. After habitat destruction, I would guess that prowling domestic cats are the main cause.

A bird-banding group in Massachusetts provides a graph clearly showing the drastic decline in birds caught and banded in their area from 1970 to 2003, at http://www.manomet.org/news/archives/#birdtracks.

When I was a child all through the summer Rain Crows called from big Red Maples next to our house, and every morning Bobwhites and Meadowlarks erupted sharply and sweetly from out in the fields, and every summer night the Whip-poor-wills sang and sang. When I remember those times I tell myself that they couldn't have been so much fuller of life, so much more gorgeous and inspiring than things are now, that my old-man's mind is just painting memories as more glorious than they ever were. But that graph at the last link coincides perfectly with what I recall.

What will the next generation be like who never have seen what I have seen, heard what I have heard?

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SUSAN'S REDBAYS
The same day Leona's letter about Rain Crows arrived Susan in Florida wrote

The disease arose when Redbay Ambrosia Beetles (Xyleborus glabratus) hitched a ride from Asia on a container ship and first showed up in an insect trap near Savannah, Georgia in 2002. Since then, Laurel Wilt, a fungal disease (genus Ophiostoma) carried by the beetle has infected and killed uncountable numbers of Redbays in South Carolina, Georgia and Florida, and the disease is spreading fast. Also, it kills Sassafras and planted Avocados, members of the same plant family.

Well, the whole story, with pictures, maps and predictions -- if you can stand to read it -- is at http://www.terrain.org/articles/22/cerulean.htm.

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BIG CHURCH LAWNS
A recurring image hard to get out of my mind from the recent trip to Kentucky and back is that of all the churches we passed surrounded by big, short-mowed lawns. During the trip we beheld many ecological travesties, all kinds of pollution, increased coal-stripmining and more and more crammed-together people competing for ever-diminishing space and resources, yet the images emerging in my mind as most iconic of the human headset causing the current planetary biosphere collapse is all those sprawling churchyards, all closely cropped.

It's because even with my unreligious but spirituality-seeking mind I still associate religiosity with spirituality, at least a little. The problem with that is that my experience has been that anyone sincerely on a spiritual quest automatically develops a profound sensitivity to, and respect for, life in all its diverse forms.

Yet, mowed lawns represent the exact opposite of sensitivity to, and respect for, life in all its diverse forms. In any context a mowed lawn is an unstable monoculture needing lots of gasoline, chemicals and money to maintain, in a place where an oxygen-producing, species-diverse, joy-to-work-in garden ought to be.

At http://www.foodnotlawns.com/lawns_to_gardens.html I read that today 58 million people in the US spend about $30 billion every year to maintain over 23 million acres of lawn. That's an average of over a third of an acre and $517 each, and I suspect that if the page were updated to reflect recently skyrocketed energy and chemical costs the price would be double. The above site also points out that each WEEK lawns in the US consume around 270 billion gallons of water, which is enough to water 81 million acres of organic vegetables ALL SUMMER LONG. Lawns use ten times as many chemicals per acre as industrial farmland.

But, back to those churches with vast, manicured lawns. Each time I saw one on my recent trip a litany of questions crossed to mind:

What are the chances that in those churches surrounded by sprawling, close-cropped lawns the sermons ever deal with matters such as water wasted, chemicals dumped into the environment, and money spent maintaining big lawns? Whey do church people try so hard to keep their grass mowed and don't even want a single dandelion to greet spring in their lawn, yet seldom if ever do they address the most engaging spiritual challenge of our time, which is how humans can be proper stewards of Earth's profoundly fragile, majestic and sacred Web of Life?

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Best wishes to all Newsletter subscribers,

Jim