Naturespeak A naturalist's view of the world

December 31, 2010

Old Acquaintances Not Forgot

Filed under: Uncategorized — wykes @ 7:48 pm

LEO is an old friend of mine who shows up every winter – more or less.  LEO is the birder’s acronym for the Long-eared Owl and represents a species name rather than an individual name. I suppose I should say that LEOs are friends of mine, but even though grammatically correct, that sounds awkward.  Come to think of it, I should never have started out with this acronym at all because it has led to several wasted explanatory sentences. But, we must move on to the owl at hand and not dwell over spilt words.

Long-eared Owls traditionally show up on our Southeastern Michigan doorstep every winter. These basically northern owls spread south during the cold season to seek out productive mousing fields and roosting thickets throughout the lower 48. The Hawthorn thickets and scrubby wetlands of Lake Erie Metropark fit their winter needs very well and we are seasonal hosts for multiple LEOs from December to March. The neat (did I just say neat?) thing about Long-ears is that they roost communally. This means that you may rarely see them, but when you do spot one it is rarely alone.  The winter birds group together into roosting groups (Parliaments) usually numbering from 2-12 birds.

We have been fortunate over a better part of the past decade that our returning owls have chosen roost sites close to the trail system – easily viewed (and photographed) within a few dozen feet from the path edge. Because these owls tend to shift their specific roosts from year to year, their new locations had to be discovered every year. It had become natural habit to look in the “usual places” until they were revealed. But, because of their fidelity to their chosen roost, once found they were easily re-found within a  season. I have, in fact, brought them to the attention of Naturespeak readers (all two of you) several times in the past. I do this because they are incredible looking beasts. To look into the eyes of a Long-eared owl is to glimpse wildness.

True to their wildness, these owls do not consult with us humans when they make their annual selection of winter roost sites. As to what the LEOs are looking for when making this choice, researchers are not really sure. They often choose the close branching cover of evergreens when they are present, but at Lake Erie they pick fairly open spaces located within a thicker tangle of Buckthorn and Hawthorn. Certainly the location also depends on easy access to the mousing swales, but beyond that there appears to be no common trait. Of course, I say this with the necessity of adding “as far as we can tell.”

For the past several years, the owls have picked locations far removed from the trail system so they were not as accessible to the paparazzi of camera folk as they were earlier in the decade.  Given the dense nature of our hawthorn thickets it doesn’t take much to hide among the scrubbery.  It was almost as if they were trying to re-assert their wildness by becoming less predictable. I was fairly certain that the supposed disappearance of our LEOs was a matter of perception and not reality. This year my hunch was confirmed.

Last week, a LEO roost was uncovered by one of the Christmas Bird Count birders working a “remote” section of the park.  There are six owls using this spot. I went, with a small group of friends, to visit their parliament hall and say hello to some old friends. We stayed only a few minutes, admired them from afar, and returned to the trail as quietly and directly as possible – leaving them wild and only lightly bothered.

The sight of multiple owls was reminiscent of old times for me. There was a good chance that the meeting was slightly reminiscent for the owls as well. These birds can live well over 25 years and, given that they are devoted to their winter roost areas, this means that they have probably seen me many times before.  This would go a long way toward explaining their look of utter surprise mixed with regret – there are some old acquaintances that are best forgot

December 28, 2010

Winter in the Bag

Filed under: Uncategorized — wykes @ 9:01 pm

At first glance, the line of Blue Spruce trees bordering the parking lot of a local Walgreen’s Drug Store appeared to be decorated for the season. Pendulous spindles adorned each branch in a rustic, but tasteful, manner. “Ah,” I thought, “some refreshingly understated décor, how…how… refreshing.” Pointing this out to my infant daughter, I said something about Santa and his elves adorning every tree in town just for her. We were doing some last minute Christmas shopping and any excuse to extend the magic of the season was welcome.

Yes, this magic moment lasted for exactly three and 1/2 seconds as I suddenly remembered that my daughter was no longer an infant, but a full grown school teacher with a career of her own. She was in town for the holiday and we were running some last minute errands.  Instantly changing my intended statement in mid sentence, I recovered and pointed out the decorations for what they really were: bagworm sacs. Although she didn’t squeal with delight, she dutifully reacted with interest.

True, the term “bagworm sacs” doesn’t roll off the tongue like “Santa’s special ornaments” but that doesn’t make them any less interesting. These trees were heavily decorated around their lower branches as if an army of short people did the tree decorating (elves?). I will, for the balance of this discussion leave behind the reality that bagworms (the sac makers themselves) are considered pests in most circles. This would further denigrate them in my infant…er, my adult daughter’s mind. I’d have to call them “Little disgusting pest bags” and we’d both have to scream in mock disgust: “Eeee-yew.” Under the influence of this mindset, we’d be looking at an infestation rather than a decoration.

Bagworm sacs are spindle-shaped bags constructed of silk and plastered with dead spruce needles (although they are known to eat just about any plant – over 100 food plants – they prefer evergreens). Each structure is secured to the branch with a silken tie and, depending on whether they were made by a male or female worm, are either empty or full of eggs. Sorry, I’m getting ahead of myself aren’t I. “Eeee-yew” I hate it when I do that. Bagworms, you see, are a type of moth that spends their larval period as a caterpillar within a mobile home. The larvae weave a silk bag which incorporates leaf bits as camouflage. They crawl about with their head and prolegs exposed and their hind quarters hidden within the bag. When threatened they withdraw into their raggety shelters to cover their location.

Sometime in late summer the mature caterpillars stop wandering about and tie their travel bags to a permanent location. In so doing they draw shut the larger open end of the bag like a purse. The smaller end has a narrow flexible opening and this is left unaltered. Encapsulated within this suspended chamber, they turn about to face downward and pupate. Eventually they emerge as adults in the early fall. The males, wasp-like creatures with clear wings, push their way out of the bag and fly off to seek the company of the females. The females, however, are wingless and are forced to remain within the confines of their bag. When the males find the females they mate with them through the narrow opening at the small end. (I would never never reveal this fact to my infant daughter).

The impregnated females lay their egg clusters within the bag before crawling out and dropping helplessly to the ground. She will lay upwards of 1,000 eggs. Both sexes die shortly after mating (although the males are able to visit with a few more bags before cashing it in!) All this means that by wintertime only the female bags will contain living material in the form of yellowish egg clusters. The male shelters will be completely empty or contain the empty pupal skins.

All that was left for us to do was to cut open a few of the Walgreen bagworm sacs to see what they contained. Of the five that were harvested, four contained only empty pupal skins and were therefore male chambers. The fifth was a female chamber but the pupae had been infected with a fungus so she never emerged.

There is nothing like an infected ornament to cause one to lose the Christmas spirit so I decided to leave the remaining 5,689 sacs intact. Too bad my infant daughter isn’t a science teacher because she could bring a bunch of these things back to her classroom and have the kids cut them open. “Eeee-yew” they would declare in synchrony.  My daughter is an orchestra teacher, so we couldn’t see any way to incorporate bagworms into the classroom setting unless it was to make them into tiny bagpipes or something. I’m still not sure how a 4-year old was able to earn a teaching certificate.

December 24, 2010

Robin Peter Toupee Paul

Filed under: Uncategorized — wykes @ 2:53 pm

It should no longer be a “new” fact, or an item of surprise, that many robins stay all winter. They have done this for a long time and are doing it more and more. Yet, I still get raised eyebrows when I mention winter robins and the fact that I normally see my first robin of the year on Jan. 1st. Of course, there are many times when I get raised eyebrows no matter what I say, but I know that at least a few of these incidences were robin related. This has got to end, if for no other reason that it denies the basic truth that robins are capable of being tough cold weather birds. They are Christmas birds.

Let’s start by putting robins on our Christmas cards. Wildlife centered Christmas Cards tend to show cardinals and chickadees artfully arranged on evergreen branches or perched upon holiday wreathes. An occasional ruffed grouse or pheasant makes the picture card scene as well, but never – at least in my vast worldly experience – do we see robin art on Christmas cards.

Granted, this concept would take a period of adjustment but it would eventually catch on. Heck, batman has his robin so why couldn’t Ole St. Nick have a side-kick/helper/worker robin? He couldn’t be called Santa Robin because that would infer that Santa was some sort of thief (does no one else care that a Santa Bear sounds suspiciously like a jolly naked elf?) but perhaps a long official sounding name like Robin Peter Toupee Paul? No one, except rich Peter people, would object to the notion of a Robin Hood Christmas bird. In fact, the thought of a somewhat shady holiday sidekick might have some appeal. He would wear a toupee that makes him look like Wayne Newton in order to disguise his real identity.  Robins are not shady in the least, but a fictional Robin Peter (call him Robin P.T.P.P.) character might be good P.R. to bolster an otherwise ubiquitous milk-toast reputation. Look at what the Grinch did for…for… bankers, for instance.

Robins are tough, so they really don’t need reputation boosting (or toupees). The only real reason birds migrate in the first place is food. Winter cold has little to do with the decision to head south. Keep in mind that migration is a dangerous energy-demanding business and there is always a trade off between costly travel and costly on-site survival (In other words, is it worth braving the traffic and expending gas costs to go across town to save a few cents on a bag of Christmas candies at another store?). Because robins have the ability to switch over their diet from worms and other invertebrates to fruits and berries, they have the option to survive winter conditions without risking long dangerous flights. In any given population of robins, however, a majority of them choose to migrate anyway – which is how the whole “first robin of Spring” thing comes from. There are migratory robins that leave and return just like they are supposed to. In fact, most of them do this. But there is also a significant minority that opts to stick around the North Country. Why some ultimately choose to go and others to stay remains a mystery, but even those that stay really don’t stay put for long.

The scientific name of the American Robin is the somewhat ridiculous sounding “Turdus migratorious.” Improperly translated this means “universal pooper”. Properly translated this name means “migratory thrush” or “thrush always on the go.”  For that significant portion of the robin population that over-winters, this translates into a constant wandering search for berry producing trees. Robin flocks will be around your neighborhood as long as there are freeze-dried hawthorns, rose hips, mountain ash and poison ivy berries to eat. They move on to new pastures when that crop is depleted.

Apart from switching to vegetarian diets, winter robins also bury their normal territorial ways and become communal. This not only increases predator awareness but also increases the chances that any individual bird will stumble upon a rich crop of shriveled berries. The availability of liquid water is one of the biggest restrictions imposed by winter life. Robins are fanatical bathers during the warmer months. They are oily creatures known to bathe twice daily in order to keep up their appearances. Perhaps it is because of this liquid need that winter flocks tend to hang out near water sources.

I recently watched a winter robin flock work a section of scrub woodlot. These birds, nine individuals in all, were picking multi-flora rose hips and buckthorn berries. True to form, they were restless eaters that rarely staid in one bush for very long. They flew about like wind-blown leaves. Every now and then, one or two would fly over to a frozen canal and sip melt water from the surface of the ice (see here). Seeing these hardy robins, standing ankle deep in frigid ice water, brought home my initial point that robins are real winter birds – not just amateurs.  As the robins flew off I began to hum the prelude to “Rudolph the Red-nosed Reindeer” – ending with “but do you recall the most famous robin of all?” I was, of course, referring to that rascally Christmas bird: Robin P.T.P.P.

Merry Christmas to All and to all a good night.

December 20, 2010

The Eating of the Shrew

Filed under: Uncategorized — wykes @ 11:23 am

Saw-whet Owls have not been spotted around Lake Erie Metropark since late fall, but it is very likely that the tiny predators are still hanging about for the winter. They are northern birds, after all, and not at all adverse to our relatively mild winters. Unfortunately, since they are so small and secretive, the actual act of seeing one becomes a matter of luck. The name “Saw”-whet is somewhat of a misnomer. Getting a chance to interview one? Well, that opportunity is even rarer unless you have a mist net handy. One of the last visible Saw-whets, although it departed before I reached the scene, did leave behind a press packet before leaving. His information packet did not include any 8” by 10” glossies or resumes, but it did answer at least one of my potential interview questions: “When visiting here, what is your favorite food?”

His “press packet” was in the form of a matted lozenge of hair and bone, or, if you prefer more exact verbiage, a pellet. I picked up the packet and picked it apart to reveal the answers contained within. Now remember, a pellet is not a poo so please don’t get all weird about touching something like this. These two items come out of the opposite ends of the bird. Just remember this phrase: poo is butt propelled and pellets are beak propelled. A pellet is a bundle of indigestible fur and bones which are egested, or coughed up while a poo is the end result of digestion which….now really, are you going to make me go on? My secretive Saw-whet did leave some of the other stuff dripped upon his perch, but it was the beak propelled matter that mattered to me. No, I did not touch the poo.

To those of you who are familiar with pellets and the products they contain, I realize the previous paragraph was probably un-necessary. Remember, however, that we often have to explain to the uninitiated why road kills, dung, pellets, and other cast off remains are useful.

Saw-whet pellet before opening

As stated previously, the pellet was lozenge-shaped and a hair over 1.75 inches long (that was a pellet joke intended for the initiated). This shape, as a matter of fact, could be described as “shrew-shaped” – an ironic trait as it eventually turned out. Armed with a pair of tweezers and a pair of fingers, I carefully pulled the tightly packed unit apart.  Within seconds, a shrew skull came into view and I was delighted to find that it was complete. The rest of the bones represented the usual variety of leg, hip, and vertebrae. Once all the skeletal parts were extricated and laid artfully into a circle of death it became apparent that at least two creatures were represented (see beginning photo).

For any pellet-picker skulls are a must because they are virtually the only easily identifiable micro-skeletal parts. It is near impossible to tell anything from the smaller bones (not impossible, but veeeeeeery hard). The identity of the skull in this case was obvious. It came from a Short-tailed Shrew (see detail below). Shrews, although mouse-like in size, are hyperactive little predators equipped with sharp reddish brown teeth and “fangs.” Short-tails can inject a paralyzing venom into their victims (mice, worms, insects) via large modified incisors and these teeth are very apparent features – both on the skulls and in life (see dental exam photo here). Most mammalian predators won’t eat shrews because they are musky but Saw-whets apparently like the pungent bitter taste of shrew (I would equate this with people who drink martinis).

About half of the remaining bones in this packet were from this shrew. Most pellet bones are white, but for some reason those from the shrew were still red with blood. A perfect set of pelvic bones, some long bones, and a wide assortment of ribs and vertebra were of shrew origin.

There was an additional set of long bones and a pelvic assembly in the pellet that could not have belonged to the shrew unless he was a double-hipped freak of some sort. These bones, which were white, came from a slightly larger mammal. Since there was no skull to complement this assemblage I would have to guess White-footed Mouse as the previous owner of these bones. They could be from a House mouse as well, but that is too hard to tell. The mouse’s head, the one thing that would answer this riddle, is in another pellet out there somewhere.

None of these results are radically different from the expected. Food studies on Saw-whets typically rank mice, such as White-footed and House, along with Short-tailed Shrews as normal fare. The mice are definitely preferred, but the shrews do make a 3%-10% showing. If nothing else, our little pellet discussion has at least confirmed that one of the primary Saw-whet Owl jobs is to create dead-headed mice and to turn Short-tailed Shrews into Short-lived shrews.

December 16, 2010

Kingling with Minglets

Filed under: Uncategorized — wykes @ 9:46 pm

There is only so much birding patience available when the temperature is hovering in the single digits. I was, patiently, trying to get a good look at the tiny mouse-sized bird flitting through the branches of a spruce tree. The thing was in constant motion – first on top of a branch, then underneath it, then hovering in front of it. It was probing, picking, peering, and prying into every possible nook and cranny provided by that tree. I finally identified it as a Golden-crowned Kinglet, due to the fact that it was a hyperactive mouse-sized bird prying into every available nook and cranny. The fact that it was pale greenish in color and topped with a black-bordered yellow crown only confirmed the identification. Unfortunately, my patience quickly faded once identification was achieved.

I decided to try for a photo op, but the bird would not stop moving. Even chickadees will pause every now and then to take a breath or to perform mental math. This one, however, consistently stayed one-half second ahead of my focusing abilities. With a digital camera you can see your image as a momentary freeze frame immediately after the shot is taken. Image after frozen image revealed this Kinglet as a blurred smudge, a well-focused butt, a set of precisely focused tail feathers sticking out of a blob of protoplasm, or as a terrific view of an empty spruce branch. Finally, after losing all feeling in my glove-less camera hand, I fired off a series of random shots before giving up. Frankly, I didn’t care at that point either. Yes, I saw a Golden-crowned Kinglet. They are not rare…they are, in fact, common winter birds. They are tiny and secretive and I was numb and slurring. Why kingle with minglets…or, I mean mingle with kinglets, when I could easily do the same thing later in the day when it was twenty degrees warmer at a balmy 26 degrees F.?

Yes, I whimped. Deciding that flesh performs better when it is not blackened and peeling, I abandoned the pip-squeak to its own devices. Afterwards, to my horror, I noticed that one of my shots actually came out o.k. – I mean it pretty much represented a fairly tolerable image of that little sprite (see last photo and detail here). I could even tell, based on the lack of an orange center on the yellow crown, that it was a female. Now I was forced into writing a blog about Yellow-crowned Kinglets in order to justify this shot. I was going to write something about hibernating clams, but nooooooooooooo….a fickle mini-flicker of fate intervened.

Nearly every bird guide will use the words “constant motion,” or something with a parallel meaning, when describing Golden-crowned Kinglets. Even their wispy “see-see-see” call is ventriloquistic and fleeting. My experience, therefore, was typical. Early investigators, of course, never had this problem because they would shoot them with rifles rather than Canon Powershot cameras.  Audubon never had to put up with hyperactive little birds when he had his Kentucky rifle loaded with birdshot. Today we have to suffer the consequences of remote observation so that we needn’t snuff birds in order to identify them. Thanks to those earlier lethal methods of freeze-framing, however, we have Audubon’s paintings and detailed scientific studies which tell us why these little guys are so hyperactive.

Golden-crowned Kinglets are the smallest winter bird in our region. Measuring barely 3 ½ inches in total length and weighing only .2 of an ounce (that’s 6 grams for you Canadians out there) you’d think they are not the over-wintering type. Ruby-throated Hummingbirds are half the weight of the average Gold-crown, but at least they have the common sense to migrate south. This leaves the kinglet as our smallest bird for six months of the year. One of their winter survival tactics, apart from fluffing up and snuggling with their fellow kinglets from time to time, is constant eating. Constant eating requires constant foraging and constant foraging leads to perpetual motion. They can’t afford to stop for too long.

Scientists, using tiny dead birds I might add, were able to determine that kinglets were eating large quantities of scale insects – tiny crust-covered critters adhering to spruce and pine needles. My little Kinglet often hovered out in front of a branch and picked off the scale insects from the spruce needles as I watched (in fact, one of my blurry out-of-focus shots shows this activity – see above). One surprising result of the last quoted study (by eminent energetics researcher Bernd Heinrich) revealed that these birds were also finding an incredible number of over-wintering caterpillars. Out of the 483 winter prey items recorded, 287 were inchworms!  Previously no one suspected that these caterpillars were even available as winter food, leave alone in any quantity.

It takes a lot of inchworm hunting to measure out a winter, so I must end with a respectful nod to this hyperactive little mouse bird. Even in the midst of her life or death struggle, she apparently sacrificed a full second of her time just to smile for my camera. I was just too slow to realize it until after the fact.

December 13, 2010

In Praise of the Pod

Filed under: Uncategorized — wykes @ 9:11 pm

For some reason, fall, winter, and even spring are not considered part of the Lotus season.  It is true that the plants produce those huge circular leaves and mega-blooms during the summertime and that one of the best times to photograph an American Lotus, at least along the Lake Erie shore, is in early August when the plants are supposedly at their peak of beauty. But, I use the term supposedly because a.) I like the word and try use it as frequently as possible and b.) because Lotuses really don’t have an “off” season. By this I mean the fall/winter seed pods certainly rival the fascination quotient of the summer flowers.

The whole purpose behind those magnificent summer flowers, after all, is the production of seed pods. It can be argued, as I am here, that those magnificent showerhead seed pods are the peak production product of the American Lotus. The flowers are merely ephemeral brushes, or chisels, used in the making of a final artistic product. I am fairly sure that if you ask a Lotus what it is most proud of, it would say “why, my seed heads of course, you spatterdock you.” (spatterdock is a derisive term used among Lotuses – something like “poopyhead” in our tongue).  Fortunately lotuses don’t really talk to sane people and therefore are unable to insult most folks. But, isn’t the fact obvious! Lotus seedpods, and the seeds contained therein, are the pinnacle of Lotus art. You’ll note the repetitious use of the underlined are as a cheap literary trick (often employed by spatterdocks such as myself).

This was a banner year for the lotus plant in western Lake Erie. The beds were as expansive as ever and the individual plants were as robust as ever. There is no need to underline this fact because the robust pods that resulted out of this year are emphasis enough. I present, as an example, some of the pods which came out of the Plum Creek estuary. These are some of the largest Lotus pods that I’ve ever seen. Some of these seed heads were over 8 inches across (see below). They were expanded beyond expected limits to the point of being moon-faced and nearly semi-circular.

Structurally these heads are basically stemmed cones with seed receptacles on top. The individual pockets which house the seeds, are arranged into 2-3 concentric circles starting with a center cluster. A wrinkled lip surrounds the crater field. Most of these gigantic examples exhibited 35-37 craters but a few perfect miniatures, only a few inches across, had only 10 or 11 misshapen craters. Some had already shed their seed crop and their empty holes were filled with ice and  coated with fresh fallen snow. Others retained a heavy load of blue-gray seeds yet to be distributed as God intended. After a few more trips back and forth over the rising and falling waters these too will eventually cast off their load to the rich mucky bottom.

Lotus pods are durable and woody but winter tends to tear them to shreds. By the advent of the following spring they remain only as tattered remnants. Even these remnants will be completely gone by the time the summer shift returns. Their job is to float the seeds as far as possible from the mother bed. Once they’ve accomplished their task they serve no other purpose other than art. A few always manage to find themselves onto mantles and into dried flower arrangements where they will last practically forever. But, no matter how long the artful pods are allowed to survive, even with a coat of varnish or gold paint, the seeds will always outdo their pods.

The end of the pod phase means the beginning of a phase which pays no attention to seasonal whims.  Lotus seeds are among the longest surviving seeds on the planet. They are coated with a flinty hard shell which is impervious to both air and water. Only scarification (essentially cracking) will allow the inner embryo to grow. They can lie dormant for decades- over 200 years is an oft-repeated figure for the American Lotus. The seeds of the closely related Sacred Lotuses of Asia have proven to be viable after some 400 years (466 years to be exact) with claims supposedly exceeding 1,000 years! See, there’s that word again, supposedly. I use it because there is really no way to know just how long a lotus seed can last. It is safe to say that they last a very very very long time. The seeds are not intended for immediate use but are meant to be time capsules which carry genes into the distant future.

Have lotuses achieved near immortality in both art and life? I could say that supposedly they have, but one thing is certain – the season of the Lotus never really ends.

December 9, 2010

A Winter Ready Bird

Filed under: Uncategorized — wykes @ 9:55 pm

When I spotted the still form of a ruffed grouse in the road ahead I just had to stop and pick it up. It was a brisk frosty Northern Michigan morning, and the poor thing had apparently just been struck by a car only minutes before I came along. It was a beautiful bird – the kind of road kill that had all the vitality of life without the life to go with it (yes, that may sound odd but it beats saying something like “it was in great shape except for the fact that it was dead.”).  In other words it was well worth examining (see here). You know what they say about a bird in the hand…

One of these birds had nearly collided with me only a half hour earlier when it careened out of the pre-dawn darkness and clumsily landed in front of me as I walked to the car. It was so dark that we both had to eye each other suspiciously for a few seconds before recognizing each for what we were. The grouse, its light sensitive eyes finally making out my human form, re-exploded into flight and took off into the dark space across the road. My wife and I also went off into the darkness and left our Dollar Lake cottage for the three hour journey back to our work-a-day world. Seeing the dead grouse so soon after this incident seemed more than coincidence. I don’t believe that God was telling me anything important, however, other than “it is time to ponder a grouse” (although I’d be the first to admit that I could have mis-read the message. Was he trying to tell me to build an ark out of feathers?).

My plump hand-held specimen of road killed Grouse was a female but, as I will explain, at first glance there was no way to tell. Several general grousy things immediately struck me about this bird. First of all, the dazzling array of mottled brown and gray feathers was astounding. Though not brightly colored, this grouse was certainly a work of art. It is no wonder that Ruffed Grouse are masters of camouflage. They can become invisible against any earthy backdrop.

The head was adorned with a crest, fallen in death but easily erected by a gentle push of the thumb, and the stout bud-eating beak betrayed its close relationship to pheasants and chickens. One thing that was not immediately obvious was the ruff for which this species was named- a trait marking it as a female. Females do not possess the full black collar of their male counterparts, but they do have vestigial ruffs.  It was the tail that told the full gender story on this bird.

Grouse have substantial tails which they occasionally fan out to display particular emotions (such as “why in the heck is that guy standing out here in the dark?”). When fanned, the feathers exhibit a speckled gray background with an outer black band. Males have a continuous band and females normally have an incomplete or broken band, but this is a nebulous trait. Male tail feathers are also typically longer than the female tail plumes – 6 inches plus as opposed to less than 6 inches.  The central tail feather on my bird measured out at 5 ¼ inches and was firmly in feminine territory.

The true secret of Ruffed Grouse anatomy, male or female, lies in their feet. Everything I’ve mentioned up to this point is a digression when it comes to pondering grouse. These wonderful appendages are worthy of a very close look. As winter approaches, grouse grow a set of snow shoes that allow them to walk lightly over the wintery landscape. Rather than simply growing a fringe of foot feathers they actually grow comb-like projections, called pectinations, along each toe (see above and here). In the manner of good snowshoes they act to spread the bird’s weight out when on lightly crusted snow. These solid horny plates do not begin growing until September. They are retained until spring, at which point they fall off.

Our road kill bird was equipped with a full set of snowtires. Here we have an incredible adaptation for living in northern climes matched only by the prodigious pads of the Snowshoe Hare. Perhaps I will run into one of these mammals in the near future (literally), but for now I’ll leave you to marvel at one of nature’s better avian designs.

December 6, 2010

Lake Harriet Coots in Action

Filed under: Uncategorized — wykes @ 4:17 pm

It is hard to admit that I wasn’t really paying attention. We were at Spring Mountain Ranch State Park in Nevada and the scenery behind the Interpreter, yellow Fremont Cottonwoods backed by a layer cake slice of mountain slope, was stealing the show. He was explaining all about the varied geology of the region, including the ancient limestone bluffs before us, but my attention was drawn to a clear green pond which reflected this glorious vista. Specifically, I was drawn to the coots swimming upon it.  As a professional interpreter myself, I was torn between courtesy and curiosity. Fortunately this was a sizable group and I was able to wander off without much notice (I was performing the A.D.D. role in this particular assemblage).

American Coots are not an unusual sight for me, so it would seem a terrible shame to suddenly be drawn to them in this situation. We have thousands of them in the cold waters of the Detroit River back home. In fact, given the huge watery expanses of my native Great Lakes it is a wonder that I would be all that fascinated by a little artificial spring-fed pond in the desert.  This pond, dubbed Lake Harriet by the rancher who created it in 1948, happens to hold one of the last surviving populations of the highly endangered, and wonderfully named, Pahrump Killifish. However, since these peanut-sized residents were submerged and unseen, the coots provided the main show.  There were about a dozen of these chunky black waterfowl milling about. Better yet, our human presence posed no barrier to their natural behavior and they were fearlessly going about their daily routine as if we were nothing more than a herd of two-legged horses (or asses?). The opportunity to observe any animal “au natural”, no matter how common, is always worthy of time.

Coots are a gregarious species but this does not mean they are amiable. They are, as a matter of fact, quite the opposite. They are constantly arguing, posturing, slap-fighting, and cackling in order to maintain balance between the crazy coots and old coots (etc., etc.). Calling upon a repertoire of some 14 different posture displays, they can convey a whole host of cooty emotions. These Lake Harriet coots were exhibiting at least five of these textbook behavior patterns – three of which I’ll describe.

Although I saw the behaviors first, it wasn’t until afterward that I was able to attach some definitive meanings on them. Credit for that definition goes to Gordon Gullion who wrote the definitive paper on coot displays in 1952. Fittingly, Gullion was with the Nevada State Fish and Game Commission at the time he conducted his study so it is, after-all, appropriate to discuss coot ways while in Nevada.

Two of the more subtle and fascinating displays are called “Charging” and the “Paired display.” A charging coot is actually more of a slinking coot. With head held down at water level and the body profile reduced to a minimum, a charging coot silently advances on an opponent (see drawing below). One of the birds I watched, and the one which I used as a model for my drawing, swept his head back and forth like a mine sweeper. In this case, the bird made ultimate use of its flashy white beak and frontal shield to signal “go away, you are bothering me.”  Coots are big into facial recognition which is why they present this part of their anatomy first. This usually precedes “spattering” in which the bird quickly picks up speed and begins to run across the water to chase away the bothersome fellow coot.

“Charging Display”

Far and away the most unusual display is the “Paired display.” Head lowered, neck feathers ruffled, the birds raise their wing coverts as high as they will go and stick their rumps high in the air to display their white tail feathers (see drawing below).  It is, as the name implies, usually conducted by a pair of birds trying to intimidate each other. In this case, it is the butt that does the speaking (see “end” photo). They maneuver in such a way as to present their tails to each other as if to say “See this? This is the rump of power.”

One side of a “Paired Display”

Both of the above actions usually led to a direct fight in which two birds went at each other chest to chest like tiny game cocks. They used their huge lobed feet to slap away and scratch at their opponent while cackling at top volume. One usually attempts to grab and hold the other down until he/she either flees or drowns! Fortunately all the fights I witnessed were short-lived and ended non-fatally. I hate to say it, but this act reminded me of two old ladies fighting over the last bag of discounted Christmas candy at Walmart.

Of all the coot postures and actions I was witness to, I found the tail-up pair display to be the most visually satisfying. This was a graceful – almost swan-like – act that, up until my Lake Harriet encounter, I would normally have called very uncoot-like. Now, I know that there is more to a coot than meets the eyes (and that A.D.D. can have its benefits).

The “Paired Display” viewed as it was intended

December 2, 2010

That’s No Chipmunk

Filed under: Uncategorized — wykes @ 4:44 pm

When a small striped beggar approached our naturalist group at Red Rock Canyon (Nevada), several in our group proclaimed it to be some sort of Chipmunk. It was, after all, a rodent marked with those familiar backstripes and fully equipped with “feed me” eyes. We were just sitting down for a brown bag lunch in the middle of a gravelly Joshua Tree  desertscape, however.  Though there are Chipmunks in Nevada and the far western states they are, like their eastern cousins, primarily creatures of woodland areas – inhabiting mostly higher elevation pinyon pine and juniper scrub. A majority of the naturalists in attendance were of eastern stock and could be forgiven the error. We are a specialist group, you see.

I immediately declared the thing to be a ground squirrel but, unfortunately, given my own eastern bent, was unable to say what kind. It took a sneak visit to the visitor center gift shop and a peak in their copy of the Audubon Field Guide to the Southwestern States to confirm that our visitor was a fine example of an Antelope Ground Squirrel. To be specific, it was a White-tailed Antelope Ground Squirrel. Equipped with my new, and now accurate information, I returned to pronounce my up-dated judgement but the group had already boarded the bus. They were waiting for me. (I did end up buying that Audubon Guide, which is what took me so long, and no, the bus group was not waiting for anything I had to say).

As long as you, dear reader, don’t have a bus to catch allow me to explain a few facts. Perhaps the best way to identify a ground squirrel on sight is to look at those shriveled little ears. These appendages are cropped off very close to the head and look as though they were clipped. The Thirteen-lined Ground Squirrel is an eastern member of this group which shares this somewhat earless trait. In this case, as a white-tailed member of the Antelope Squirrel Club, the two dark-bordered side stripes and the white-bottomed tail are very distinctive (see detail shot here). The species often runs with the tail held so tightly up against the back that it appears to be an additional white body stripe (see below). Chipmunks run with their tails straight up and have large ears and, like I said, don’t live in the desert.

Our beggar never made it close enough to actually accept any offerings. It had chosen the wrong group from which to beg (naturalists…hmm, hmm… do not throw food at animals – at least not when in the company of other naturalists. We spend far too much time telling other people not to do this). I offered it an imaginary treat in order to lure it closer but the ruse was short-lived and this creature soon turned “tail” and ran to the shelter of a creosote bush. Antelope squirrels are not dumb. Do not try this with raccoons, by the way, because they get angry when fooled.

Ground Squirrels are one of the only small desert mammals who are active at mid-day. This being mid-November, the spritely little fellow was certainly in no danger of drying out in the sunlight but earlier in the summer it would have been subject to very hot dry conditions. Fortunately, they are perfectly adapted, both physically and behaviorally, for life in arid climates. To start with, they can get all their moisture from their food which includes an eclectic mix of foliage, seeds, insects, and even a lizard or two. They are omnivorous and not strictly “seed lovers”, as their Latin genus name Ammospermophilis implies.  They avoid Hyperthermia, the state of over-heating, by retreating into the shelter of their shaded burrows or climbing into the low shrubbery to take advantage of the cooling air flow. Should their body temperatures rise above normal, they can tolerate internal temperatures of 104 degree F. without dropping dead or requiring basting.

There were dozens of burrows about the site where we saw the ground squirrel in question and all were located near the shaded base of the local cacti, Joshua Trees or saltbrush.  It has been well documented that over-heated Antelope Ground Squirrels will deliberately press their scantily haired bellies against the cool sand at the entrance of their holes in order to transfer heat and cool off. They maintain an abundance of burrows throughout their range so that relief is always near.

Of course, those burrows also represent sanctuary from a whole host of predators as well. Small juicy mammals are prime food for hawks, owls, coyotes, and fox. Our little squirrel was protected from depredations by the presence of people and was able to operate in full view without fear. Not too far away and along one of the trails leading from the visitor center I came upon some well-dried coyote scat. The sun-hardened relict contained numerous bones – many of which looked to be those of a desert cottontail or jack rabbit – but one set of small gleaming incisors were obviously Chipmunk sized (see below and detail here). I put the poo back down without probing the mass, but I’d be willing to bet those teeth belonged to a White-tailed Antelope Ground Squirrel whose desert luck had run out.

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