Naturespeak A naturalist's view of the world

April 29, 2008

Of Bee Hills and Buttermoths

Filed under: Uncategorized — wykes @ 2:58 pm

 

  Every now and then I like to turn things upside down in order to see them from a different angle. They say that such a thing actually puts the right side of your brain to work and, incidentally, causes a lot of things to spill (never look at the bottom of a glass when it is half full, for instance).

  Nature delights in turning things around as well. I suppose she does this to give us a different view of life and confirm that we should never assume anything when it comes to the natural world.  It would be natural to assume that a tiny sand hill with hole in the center is an anthill or that a colorful winged insect flying at mid-day is a butterfly. As a small way of turning your world upside down, allow me to introduce the exceptions to these examples.

  First of all, what about those anthills?  Yes, some ants do make sand hills. These hill-lets are possessed of a central entrance for ingress and egress, but I digress. Should you come across a sandy spot with a cluster of apparent anthills where the central holes are about ¼ inch wide and open slightly off to the side, you are actually looking at bee hills.  If you stick around a minute or two you’ll spot the specific bees belonging to these structures as they return to the surface and poke their heads out.  Take a look at the picture above and you’ll see two of these Solitary Bees guarding their burrow entrances.

  Solitary bees are members of a group of bees called mining bees (see a close-up here). There are some 1,200 species in North America, so I can’t tell you the exact species of the ones I encountered.  These insects produce neither honey nor beeswax. Oddly enough, most wild bees are of solitary persuasion and only a few form genuine colonies such as the caste-forming Honey Bees. This means that, although the honey/wax making species get all the glory, the vast tribes of solitary bees perform a great deal of the pollination work going on out there.

  It appears to be another turn-around of ideas to state that these so-called “solitary” bees nest in groups.  They do find some comfort being in the company of similar bees, but are not social insects in the true sense of the word. They do not co-operate or assist each other in any way – it’s a “you don’t borrow my tools and I won’t borrow yours” neighborhood thing.

  Each one of the separate but equal burrows is independently excavated by a female Solitary Bee. The main tunnel extends down into the sandy soil for a few inches. Brood chambers, or cells, are carved off to the side and at right angles to the main tunnel (here’s a cutaway view of a tunnel with a few side chambers exposed). These chambers are created and waterproofed with a waxy secretion. The female collects pollen (using special brushes called scopae on her hind legs) and rolls it into a ¼ inch ball. A liberal application of nectar provides sufficient moisture to hold it together and provide a bit of sweetener for the kids.  She then lays a single egg on the pollen ball (look here – both this and the previous shot were taken by Dennis Briggs of the University of California), and then seals up the chamber for good.

  She works on one cell at a time and eventually seals off the whole set after she’s laid eight or so eggs.  Her life work is done after several more burrows are completed.  Solitary bees do not provide any other parental care other than this initial set-up. The child bees are solo from here on out. They will hatch out later in the summer, eat up their pollen snack, pupate, and await the following spring to emerge as adults. They do all of this on their own. No bee is an island, but these come close.

  As if a community of solitary bees living in ant hills isn’t enough, I’d like to add one more contradictory insect to this essay. There is a flashy little moth out there called a Grapevine Epimenis (see here) that flies by day.  I encountered several of these on a recent walk and they all were seeking to suck up minerals from the trail limestone.

  A majority of moths are night fliers and all butterflies are day fliers. There are some significant exceptions to the moth rule. Some, such as the diminutive Epimenis, find the full light of day to their liking and shun the night. In the field guides, this black, white and red moth is listed as an early spring woodland creature that “is often mistaken for a butterfly.”  Trembling with energy, the pictured moth was difficult to approach because it would dart off as if driven by butterfly reflexes. Scientifically this species is called Psychomorpha epimenis which gives a hint at the crazy behavior of this day moth. I prefer to give it the previously unpublished title of “buttermoth.”

  If there is any lesson to be drawn from looking at bee hills and pseudo butterflies, it is that few things are as they initially appear.

April 26, 2008

The “Other” Red Wings

Filed under: Uncategorized — wykes @ 7:57 pm

                   

  Natural cycles are a grand thing. For the most part, things happen about the same way and at the same time every year.  For instance, it is end of April and the new green cat-tail shoots are about a foot tall, the fragrant water lilies are just poking their leafy heads up out of the water, and both of our Red Wing teams are reaching the high points of their season. Yes, both the hockey team and the birds are providing us with spring highlights once again – one seeks “Stanley” and the other seeks population security.

  I’ll leave it to others to discuss the Detroit Red Wings and their annual trophy quest, and instead focus my seasonal attention towards THE “original” red-wings – the Red-winged Blackbirds. My morning walk along the marsh boardwalk at Lake Erie Metropark brought me in close contact with a female Red-winged Blackbird (see above). Her behavior – sticking around, as opposed to taking off, combined with the issuance of a continual stream of obscenities in my direction– indicates that she had a nest nearby.   It is that time of year again.

  It’s worth pausing to admire the female red-wing on her own merits. She has a cryptic beauty that transcends the male attributes that are responsible for the species name.  The male is a glorious beast whose fiery epaulettes define the color red, but without the handsome little females on the team there would be no species. You could say that she represents the “other other” Red Wing.

  The female’s striped cream and brown coloration is a practical camouflage pattern meant to blend into the dead leafy landscape of the marsh. The area around her face and throat, however, has a nice salmon cast to it that lends a feminine air to her appearance (sometimes you have to say these kinds of things to keep women happy – I think). Some female red-wings even have a hint of red on their shoulders, but not this one. When sitting on the eggs or nestlings she will become invisible and that is the whole point of this color scheme. 

  Her mate delivered only a cursory warning in my direction and was more concerned with the other male birds than me. He has to fulfill his promise to the other females in his harem to keep this section of the marsh clear of competition. It was the lot of this particular female to deliberately make herself visible in order to protest my presence.  She did so with a series of raspy “kecks” where each utterance was accompanied by a tail pump. In so doing, she perched herself in that classic split-leg pose so typical of these birds (see here).

  Even though I could not locate the nest, I know it is positioned only a few feet above the water surface.  It is woven from shredded cat-tail leaves and supported by a framework of at least three dead cat-tail stalks. I know that it blends well into the background from which it was made.  I also know that she has, or soon will have, a clutch of powder blue eggs to care for. Each egg will be randomly decorated with a pattern of dark spackling (see here).

  I look forward to the day when I will finally spot the nest and can watch her raise a brood and complete another successful season. I am less confident that the other Red-wings will successfully complete their season, but, like I said, I leave that grist for the sport bloggers to grind.

April 24, 2008

Two for One Mantis Sale

Filed under: Uncategorized — wykes @ 7:33 pm

 

 Praying mantis egg cases are those familiar hard foam blobs that hold the promise of new life and garden salvation wrapped up into one package. Depending on which garden website you go to, you’ll see them offered for immediate shipment at a going rate spanning the gamut from $1.35 to $4.00 apiece. Promoted like T.V. miracle products, these egg cases come with a promise that they will release hundreds of pest-hungry predators into your garden plot like time-released headache medicines.  The hatchling mantids will grow into big mantids at the expense of your nasty garden pests and they are 100% chemical free. 

  Well, I guess most of this is stuff is true, but we loose sight of the fact that these creatures are very common and are quite capable of spreading themselves. Mantis egg cases are a regular sight in the leafless landscape, so chances are you can save a few bucks and transfer a few naturally occurring ones to your garden this spring. But, hurry because supplies will be going fast. They will be hatching out very soon.

  My intention here is not to re-tell the well known story of these beneficial insects, but instead to focus momentarily on their egg cases before they release their charges and become yesterday’s news. Mantis egg cases, like the one pictured above, are one of nature’s perfect packages and therefore worth a second look. Without them you have no Praying Mantis’- large or small.

  Yesterday, I encountered the case that is pictured above.  It was attached to a small dogwood in the midst of a field.  Like all examples, it is hard to the touch and water resistant. The material of which it is made was issued from the hind end of a female Chinese Mantis last September.  She deposited her 100-400 rice-like eggs into alternating rows and enveloped them in white bubbly aerosol foam that cured into a tan-colored rigid insulating cover. Technically these things are called Ootheca, but I tend to be un-scientific about it and call them seafoam packets. The new generation was well kept from the harsh effects of low temperature, wind, snow, and rain and the case delivered its cargo safely into the new year.

  From the top angle (see here), you can see a flat central mid-line that contrasts with the bumply ridge material to either side. The young will eventually push out of their chamber through this central section. These features are common to most, if not all mantis egg cases (There are thousands of species world-wide and I don’t want to go out on a limb and say that they all have these traits, even though I could pretend that is the truth).

  This particular case has a truncated end where it stops and slopes down at a steep angle to the stem.  Here is a prime example of the type created by the Chinese Mantis- an introduced species from that specific part of the world.  Last month I photographed another case with a very different profile (see here).  It was shaped like a tiny loaf of bread. I’m not entirely sure what species made this structure because both the European Mantis and the Carolina Mantis produce this kind of casing. The European Mantis, as you probably figured out, is an introduction from Europe and the Carolina Mantis is a native from the S.E. United States.  Since I snapped the shot locally and the Carolina is not normally found this far north, I have to conclude it’s from Mantis religiosa – the European immigrant. Neither of these cases is from a native insect.

  My point, in this case study, is to simply encourage you to take a nice close look at the next mantis case you find. See if you can figure out what specific kind was responsible and take a few moments to admire yet another example of naturally good packaging.

April 22, 2008

Sap Suck’n Brushfoots

Filed under: Uncategorized — wykes @ 6:15 pm

     A relationship in the natural world where one organism benefits from the actions of another is called symbiosis.  Unlike the sometimes parasitic relationship between a parent and a child, where the lesser life form sucks the life out of the greater beast, a symbiotic partnership is generally a plus-plus scenario. In this case, both parties benefit and need each other.  Since our children can occasionally be coerced into performing beneficial labor around the house and yard, I guess I should alter my parasitic child comment. After all, children bear a closer resemblance to those helpful tick picking birds on the backs of Cape Water Buffalo than they do to Tapeworms.

  Sometimes a symbiotic relationship becomes a plus-neutral interaction in which one party benefits and the other could care less. This latter interaction best describes the bond between the Yellow-bellied Sapsucker and the early spring butterflies.

  Sapsuckers are among the best named animals on the planet.  They are medium sized woodpeckers that suck sap and have yellow bellies, what more can I say. It is their habit to create a linear arrangement of shallow holes, or wells, in tree bark in order to induce them to weep a torrent of sap (see here and a detail view here).  Often there are so many wells on a trunk that it looks like it has been strafed by machine gun fire. The birds routinely return to these wells to lick up the sweet sap and sometimes nibble on the insects attracted to it.

  Two butterflies that regularly find comfort in seeping sapsucker wells are the Red Admiral (see here) and the Mourningcloak (see above).  Both of these gentle flyers are classified as Brush-footed butterflies because their front pair of legs are reduced to hairy pods. They are also called angle wings because the outline of the wings looks tattered and irregular. Both species over winter as adults – in other words they hibernate or go through “cryptopreservation” (controlled freezing).  They emerge from winter slumber well before other butterflies and don’t mind the chill of a crisp spring day. I mean, really, if you’ve already been frozen what’s a little dip into the 30’s!

  Cold loving butterflies, like these two, have hairy bodies and dark coloration in order to absorb as much of the sun’s energy as possible.  They spend a lot of time basking and eating high energy food such as rotting fruit, bird droppings (hey, don’t knock it), and sugary tree sap. With proper sunbathing and fuel intake, they can raise their body temperatures to a level near to our own and this enables them to fly. Since flowering plants are not available in the early season both early risers skip the traditional “butterfly at flower” thing.

  I came upon the two pictured butterflies while walking through a woodlot the other day.  I flushed the Mourningcloak first. It was imbibing at one of the sapsucker wells I showed you a few paragraphs ago. Several dozen flies were also there feeding but they didn’t acknowledge my presence at all (kinda like my kids).  Cloaks are deep purple in color with a bright yellow fringe decorated by intense blue dots. This pattern reminded the early naturalists of the cloaks worn by people mourning their dead – thus the reason they have a “u” in their name (as in “sad”). Their underwings are cryptically mottled with brown and they blend in when their wings are folded over their backs.

  The sad butterfly did not return to the sap wells during the few minutes I hung around, but instead proceeded to patrol its territory. A few trees over, several Red Admiral butterflies were more than willing to return to the bar after being flushed. Admirals are smaller than the cloaks and are distinguished by bright orange-red bands across each wing and antennae brightly tipped like match-heads. They too are mottled underneath so as to blend in when necessary.

  They usually feed upside down and you can see here the extended tongue that delivers the sap. But, they never stay in place for long.  Like the cloaks, they are territorial. The males patrol an elliptical space of ground up to 40 ft. by 75 ft. or so. Anything entering that space is chased off (even people) or, if it’s a female, mated with.  My admirals were constantly flying off, doing aerial combat with intruders and then returning for a second round of drinks.  They didn’t pay attention to the ever-present bar flies either.

  Take another look at these butterfly pictures and I’d like to point something out to you. You’ll note that these guys look pretty rag-tag at this time of year. They are near the end of their life cycle and looking for one last fling before cashing it all in. The cloaks emerged as adults last June. They dallied about for a while then estivated (a term for warm weather hibernating) until fall at which time they suck on some sap and go into hibernation. So, we are looking at a 10 month old butterfly here.

  The admirals have two generations per year, and the current individuals emerged late last summer as adults before they sucked sap and hibernated. They look a little better than the cloaks because they are four months younger.

  You know, they are always telling us to hug or kids -which is darn good advice – but have you hugged a Sapsucker lately?  They are the ones who make the trees cry and the angle wings fly.

April 19, 2008

Spring is Up in the Air

Filed under: Uncategorized — wykes @ 8:20 pm

  From the title of this piece you might assume that I am going to say that the status of this spring is somewhat doubtful – you know, as in yet to be decided or debatable.  Well nothing could be further from the truth. This spring season is charging ahead full force. It is neither late nor early, but definitely proceeding at its usual rapid pace. What I really wanted to say with this title is that the essence of spring is literally up in the air in the form of pollen and that the first pollen-producing spring wildflowers are located up in the air as well. In other words, ‘tis the time to suck in some tree dust and blow it out again (maybe that would have been a better title, eh?).  

  Trees, such as Black Alders and Red Maples are among the earliest of bloomers yet they are little appreciated for this effort. I was reminded of this the other day when I went up in the air aboard a helicopter.  We were engaged in deer counting again, but found it a difficult task without the neutralizing effect of background snow.  We did spot a few deer but only the ones that were flashing their white tummies in the morning light.  Doing an April survey wasn’t my idea – I can blame that on the Univ. of Michigan but don’t have time to explain why I was involved in this particular scheme.  Whilst airborne I got a spectacular view of the flowering red maples.  These trees added a crimson wash to a canopy otherwise dominated by gray. The view shown above is out my side of the cockpit over Oakland County and the chance to see it was a blessing – with or without deer sightings. The white pines poking through the canopy can be temporarily ignored because they are always green, whereas the maples are only vibrantly attired in red twice a year (during flowering and autumn leaf blush). O.K., you don’t have to ignore the pines. Go ahead and say “ooh” and “ahh” and “aren’t they great, etc.” and then let’s get back to the maples.

  You can see these trees blooming from down here on earth but you have to look up. Forget the late appearing daffodils and hibiscus and peer skyward in order to appreciate these much larger flowering plants.  The maples have been blossoming for several weeks and right now the red female flowers are at their peak. The male blooms started much earlier and a few are still out (see here). Each bunch of flowers consists of a cluster of five-parted florets sporting five individual yellow anthers.  Each anther is coated with grains of pollen whose sole function is to fertilize the female flowers.

 The Black Alder is another early tree flower that expresses itself in the form of a dangling pollen wand known as a catkin (see here). This is a low tree which really has to be appreciated from the ground level.  An individual male alder flower is not very impressive, but there are dozens that make up each catkin and together they make up a fascinating structure. The catkins open and relax downward when prompted by the first warming rays and shed their pollen load to the four winds.

  Since both the Red Maple and Alder are primarily wind pollinated they are called anemophilous plants (a term which literally means “wind loving”). They rely on the wind to distribute their pollen. Since the breeze is a haphazard postal service, such plants need to shed trillions of very light pollen grains in the hopes that some of them make their goal. It so happens that we are unintentionally sticking our noses into their love life by interrupting that pollen stream.

  A pollen grain is essentially a sperm packet surrounded by a tough outer coat. Most are round and elaborately ornamented and all are extremely tiny. Take a look here and you can see what the pollen grains of Red maple and Black Alder look like. Yes, that is my hand in the photo and yes, these are models.  Thank God, eh? Imagine sucking one of these things up your nose! In actual scale, the Alder grain (on the left) would be only 15 microns wide and the Maple (on the right, in case you weren’t paying attention) would be about 20 microns in diameter.

  A micron, or micrometer, is one-thousands of a millimeter, so you get an idea of just how small these grains are. If my photo were to scale, I would be only a few millimeters tall and my hands would be so tiny that I wouldn’t be able to type on a keyboard (I would, in fact, fall between the spaces in the keys and have to live off all the food crumbs found there).

  The air is now full of tree pollen and nearly all of it is wasted since very little makes it to the intended destination. Those that find their mark – being a female flower of the right species –immediately sprout a tubule which penetrates to the ovary and delivers the precious cargo. Those that are wasted end up in places such as your nose where they initiate sneezing. All maple pollen is allergenic to humans and some folks are allergic to alder pollen.

  If you are they type that gets seasonal allergies, you likely have been keenly aware that the trees have been flowering for some time. Perhaps this essay will give you something to look for in the Kleenex next time you blow your nose. For those of you who don’t feel the effects of tree dust, it’s time to stop and look up at our largest wildflowers and take in a deep breath of spring.

April 17, 2008

Oological Manners

Filed under: Uncategorized — wykes @ 3:58 pm

 

I left off my discussion of the Great Blue Heron Rookery a few days ago with a promise to show you a few of their eggs.  Fortunately, or unfortunately as I will explain, I didn’t have to make the hazardous climb to obtain them. Take a glance at the above photo and you’ll see that I am holding a typical Great Blue Heron clutch. I think you’ll agree they are, just like their producers, both great and blue. 

  The birds lay up to five of these precious packages and start to incubate them sometime before the last one is laid. Both parents trade off egg sitting duty in anticipation that they’ll hatch in 25-29 days.  Incubating the clutch before it is complete results in a staggered emergence where the first chick may be several days older than the last one out. The older birdlets, because they have the biggest mouths, sometimes gain an advantage over their Johnny-come-lately siblings. As long as ample food is available, the lessers will catch up to the greaters and the whole clutch will survive – if not, the weaker ones will perish.

 You’ve probably figured out that the eggs I am holding in my hand will never hatch.  They were denied that chance over 85 years ago when they were collected, “blown,” and turned into cabinet specimens. Those perfect little holes along with the penciled numbers should have clued you in. It used to be all the rage throughout the 19th and early 20th century for folks to amass massive egg collections.  Collectors would buy or trade treasured specimens like so many rare butterflies or minerals and proudly display them in golden oak display cabinets.  These heron eggs were gathered at the tail end of the bad old days of egg collecting and are part of the trove assembled by a regional collector by the name of W.B. Purdy of Milford, Michigan.

  Mr. Purdy was a fairly small time collector but his specimens number into the thousands. You can imagine the damage done to bird populations by the activities of these amateur Oologists (the term for the study of eggs in which both o’s are pronounced). Fortunately their activity quickly went out of favor when it was outlawed. For some birds, such as the Great Auk, this moratorium came about way too late and the collectors pretty much picked them into extinction by the early 19th century. 

  Mr. P. apparently took a liking for Great Blue Heron eggs and gathered hundreds of them. Getting access to these loftily placed eggs was not an easy affair, but obviously not one that stopped climbers using rope and tackle to get access.  One colony could yield dozens of eggs in an afternoon.  If the nest was too high to reach, the collectors would resort to other tactics.  For instance there is an early 20th century record of an egg-hog chopping down a tree that held an inaccessible bald eagle nest so that the pair would re-build in a lower tree!

  The oologist methods were frighteningly efficient. Each egg was carefully prepared, recorded and labeled. A small hole saw was used to cut into the shell and a pipette was employed to draw out the yolk (they avoided “full term” eggs but would resort to mincing up the contents if it was an especially valuable species). A specific numbering system kept things, well, systematic.  Note that two of the eggs in the picture have a fraction written on them – ¼ on one and 1/5 on the other. This means that the egg is one out of four or five in the clutch.  The second number is the official A.O.U. (American Ornithological Union) number for that species. In this case 194 is the designation for Great Blue Heron.  Finally, each labeled egg has a procurement date. One was harvested on April 24, 1922 and the other on what looks like March 6, 1923.

  Based on the extremely early date, the March egg was probably gathered somewhere well south of here.  Unfortunately, most of Purdy’s records have been lost, which means much of the scientific value of his material has vanished as well.  We don’t know where these heron eggs were gathered. There are a few exceptions, such as this set of Black Tern eggs taken from the St. Clair Flats in 1926 with their label (see here).  For the most part, we are left with a mute gallery of egg art that needs to be preserved if for no other reason than they eliminate the need to collect any more of them.  Take a few minutes and take a look at a few of the specimens: Common Loon, Red-shouldered Hawk, Common Crow, Razor-billed Auk, and an unknown species dated 1874 (apparently one of the traded eggs).

  Now these specimens have no real value other than their natural history and design merits, but at one time they each had a book value. I have a 3 inch by 6 inch “Standard Catalogue of North American Birds’ Eggs” published in 1909 which contained the going price for every available bird species.  Great Blue Heron eggs were going for 40 cents a piece, Black Terns for 15 cents, and Loons were fetching $2.00 – a nice oval figure for that day.

   The most expensive egg was that of the Great Auk.  An egg from this long extinct sea bird was listed as $1.00 with an asterisk, but the accessory mark indicated that this paltry amount was for a cast only. The real ones were commanding $1,000-$1600.   Remember this is in 1909! (In case you are wondering, the 1884 Razor-billed Auk eggs that are pictured were only valued at 35 cents back then).

  Today one thing is sure; all eggs are priceless.  A Great Blue package in the nest is worth more than ten-thousand in a drawer.

 

April 15, 2008

A New Hope

Filed under: Uncategorized — wykes @ 8:05 pm

 

Last May I featured the Great Blue Heron rookery at Kensington Metropark (see Naturespeak May 20, ’07). At that time of the year, the nests were brimming with young herons and the site was abuzz with activity and noise.  When I returned to the colony this year I found it to be a much quieter place. At this mid-April stage the nesting sequence has just begun, so I can provide you with a prequel to the late spring Heron saga (as a Star Wars fan I find this way of doing things perfectly natural).

  It appears that most of the nests survived the winter in pretty good shape (see here) so that improvement, rather than new construction, is the current need. It’s nice to know that at least one portion of the housing market has remained stable. The returning Herons have already staked their claims to their individual nests within the rookery – a process in which a male bird basically sits on a chosen site and pecks at anything that comes close. A lone Egret is again lurking around the place and likely will stake a claim within the heron neighborhood. He was apparently content with just perching down near the water’s edge until another egret shows up.

  Herons do not mate for life, so every year the males turn over a new twig and set up house-keeping with a different leggy chick. The courtship thing is a two way situation. After a whole lot of plume raising, head shaking, mandible clapping, howling, stick shaking, preening, and a little bill stroking, the mate choice is made and the pairs settle down and begin to get the nursery ready.

 I missed most of the elaborate courtship stuff, but was witness to the more subdued nest improvement stage. On this morning, the birds were spending a great deal of time just standing, or sitting, around. Several of the males were wrapped up in some excessive preening exercises. Part of this activity is done to impress the females, but most of it is performed for the sake of “look’n good.” The sinewy birds (up to 4.5 feet high) are glorious in their full breeding plumage. Long graceful black plumes project out of the back of their heads. These plumes stick straight up into air when the preener points the tip of his bill down to arrange the equally impressive set of neck fringe feathers (see above).  Scapular plumes (originating at the black shoulder epaulettes) pour down off the back. Their bills are colored an especially bright shade of yellow at this time of year.

  There is little difference between the sexes in this species, which is a good indicator that they share nesting duties. The females are responsible for most of the re-decorating, however. It falls upon the males to gather up the raw material. Being right in the middle of a laundry room do-over myself, I can appreciate this part of the process. One of the sticks I brought home did not please my mate but we are currently engaging in plume raising and should have this thing settled shortly – which means I will lose.

  Back at the rookery, I watched several males gracefully drop down to the undergrowth beneath the stately nest trees. They shopped for twigs – mostly rejects fallen from other nests – and after making a selection they flew back up to their respective nests. Being a bird endowed with a six foot wingspan the return ascent takes time and they must circle the island in order to lift their seven pound frame to the proper altitude.

  The female remains seated in the lofty nest during this time. As the male arrives with a branch, she greets him with an exaggerated stretched neck display and accepts the gift. Her “arroo” of approval may be answered by a throaty “kronk” from her mate, or the whole thing can be done in silence (such as when I presented a used cabinet to my mate as part of our laundry room project). The hen then carefully inserts the new twig into the framework and the male goes off in pursuit of an even better twig (see here- in lower nest). 

  On occasion, it seemed that the returning male came back empty-handed but was seen passing over something – perhaps a fine twiglet for the centerpiece.  These structures are really more like platforms and are not nests in the traditional sense. Even so, the egg holding portion is finished off with fine twigs, grass and even moss.  Over the years these nests can become quite large. It’s not unusual to see them reach an excess of four feet across which is the case with this set of nests.

  It can take weeks before the nesting project is considered “done.”  I believe this decision is ultimately made by the female based upon my own circumstance. Soon the couple will begin incubating their eggs.  I’ll show you a few next time, but right now I have to go do some preening.

April 13, 2008

A Rainbow Comes to Earth

Filed under: Uncategorized — wykes @ 8:18 pm

  On  Friday evening, an energetic spring storm swept through the region.  Like a herd of thundering bison, a tempest of wind and blinding rain rolled in and pummeled the countryside into submission. The assault passed by nearly as quickly as it began and the angry clouds were soon tamed by the rays of a brilliant sunset within a resurgent blue sky.

  A brilliant rainbow signaled the storm’s end and every single robin in the vicinity hailed normalcy’s return with a bubbling chorus. I happened to be just across the field from where this arc of color struck ground just in front of a distant woodlot.  It’s not often that you actually see the end of a rainbow.  Sure, somewhere over the rainbow is the land that we heard of once in a lullaby. We are always given the chance to go to Oz by looking over the thing, but glimpsing the elusive “end of the thing” is a much rarer opportunity. Oddly enough, I opted to take a picture rather than risk retrieving the pot of gold at its base (see above). 

  You see, I know that the rainbow’s pot ‘o gold is nothing more than a kettle of fairy dust that vanishes as soon as the fiery light beneath it is extinguished.  The brilliant colors – from red to blue, indigo, and violet -on the other hand, are funneled into the earth and soaked up by the life that lives upon it. I know this particular rainbow charged up nature’s color cells in a big way. Its colors were sapped within a matter of only a few minutes.

  Even a casual look around you will reveal where all this color goes. The Red maple flowers are exploding with the crimson and the Flicker’s breast is overflowing with the yellow. It seems that the Wood Ducks have absorbed everything else, but there is plenty left over for a relatively unknown regional beauty called the Rainbow Darter. This living rainbow is perhaps the best proof that none of heaven’s colors go to waste.

 Feast your eyes upon a Darter (see here) and you are looking at a native creature whose appearance rivals even the brightest of tropical fish. These stream dwellers are now entering into the cusp of their breeding season and the males are beginning to exhibit their brightest colors of the season. I actually took this portrait nearly a month ago, so the pictured fish wasn’t even in full regalia yet. It takes a few spring rainbows to get them fully charged.

  The scientific name of this 3 inch darter is Etheostoma caeruleum, which means “blue filter mouth.”  Let’s forget the filter part for now, but instead focus on the second part of the Latin name that refers to the bright Cerulean hue that defines them. These neon blue highlights are a Rainbow Darter specialty. From the edging on the dorsal fins (those spiny fins atop the body) to the prominent side stripes, this is the shade that makes the Rainbow “pop.”  When combined with brilliant reds and oranges, this garish color combination definitely makes a statement. That statement is, simply put, “Hey Baby!”

  Female darters have some flair, but are generally much more subdued than the males (see here). They select the brightest healthiest mates from their host of suitors and have no need of superfluous make-up. If a guy fish flashes the right colors, she sinks into the gravel and allows him to fertilize her eggs as they are laid.

  Darters are creatures of fast clean water and are adapted to the fast life of riffling creeks and small rivers. Their large pectoral (side) and pelvic (bottom) fins, combined with a streamlined shape and prominent eyes- located at the top of their head- enable them to move about and feed along the bottom current. There are dozens of darter species in the region and many of them are nearly as colorful as the Rainbow Darter, but none can quite claim equity. Fortunately this is one of our commonest Michigan species and their presence is a sure sign of good water quality.

  It is safe to conclude, then, that rainbows not only are the essence of light and hue but they are the essence of a healthy stream as well.

April 10, 2008

Polyphemus Awaits

Filed under: Uncategorized — wykes @ 8:48 pm

  If good things come in small packages, then imagine the kind of things that can come from big packages. The last time I got a really big package it contained a big beautiful Epiphone Broadway guitar. I could argue that it doesn’t get any better than that, but I won’t – there are bound to be those Gibson and Martin types out there ready to burst my bubble. But, I do possess another big package whose contents still await uncovery (this is not a real word, but I am revealing it here for the first time). No one can slight the contents of this package. Like my Epiphone box, my other big container contains a thing of beauty which combines subtle shades of tawny brown with brash flashes of pearly opalescence, but I can’t open it.  This package needs to open itself.  It is a Polyphemus cocoon (take a look here).

  “Big,” is a relative term, of course.  Compared to the guitar box, my cocoon is a small thing. But, since most moth cocoons are relatively small affairs, this one stands out as a super-sized menu item.  Because the caterpillar that constructed it was Vienna sausage sized (see here) and the moth that will eclose (not a made up word) from it will have a 6 inch wingspan, it is appropriate that this is a member of a group labeled as the Giant Silk Moths.

  The papery cocoon is a distinctive product built to withstand the brunt of winter.  Late last summer, the larvae snuggled within the protective folds of a few leaves and proceeded to weave a tough brown bag of silk about itself. It then imbued the fibers with a chalky white fluid that hardened into a water resistant coating. As a pupa, the insect now waits inside for that magic day in June when it will break free of its silken bounds. Unlike other giant silk moth cocoons (such as the Cecropia Moth we discussed in an earlier Naturespeak) Polyphemus cocoons don’t stay suspended but instead fall to earth at some point. This independent egg-shaped form is what identifies this moth’s cocoon from those of the other “giants.”

  It is entirely appropriate to name this creature after a giant of Greek legend. Polyphemus was the Cyclops made famous in Homer’s Odyssey. He was the one eyed son of Poseidon and the nymph Thoosa who suffered the proverbial “sharp stick in the eye” at the hands of his captives. His name means “round eye” in Greek. It so happens that the moth sharing the title with this poker faced cyclops has two of these round oculars on his back wings (see here).  Each is highlighted in black and blue with a translucent central pupil. Yes, I can hear those Gibson people snidely observing at this point that by possessing two eyes, the Polyphemus Moth is not very cyclopean, but to them I say “get over it.”

 I eagerly await the emergence of this moth in a few months and promise to report back when this event occurs. He (or she) will open the package from within with a spit wad of enzymes to dissolve the silk.  I’ve seen reference to a pair of spurs on the forewings that assist in cutting these fibers, but I have never seen this feature before. Come to think of it, I’ve never seen a giant island dwelling Cyclops either, but that doesn’t make them any less real (nor do I own a true Gibson or Martin guitar).

April 8, 2008

At a Flying Tiger’s Lair

Filed under: Uncategorized — wykes @ 8:34 pm

Great Horned Owls are unconventional even among that circle of peculiar fowl known as owls. They nest so early in the spring that they actually end up nesting in the wintertime and they do so as squatters. Even though they are quite capable of doing their own stick work, these resourceful birds are dependant upon the nest building skills of red-tailed hawks, great-blue herons, and bald eagles for a well-made platform. They take over the old nests made the previous season by these other builders and claim them for their own. Their status as “great” birds seems further diminished when you consider that their kids are expected to eat each other in the event of a food shortage.

  In truth, the nesting and rearing strategy of the Great Horned (a.k.a. Flying Tiger and Big Cat Owl) is a stroke of native genius. Owls are among the dumbest of all birds, by the way, so this genius is strictly instinctive. By starting early, they have their choice of free nest space and an exclusive supply of groceries when the young hatch out (getting to the store, so to speak, while the shelves are relatively full and before the morning shoppers arrive). 

  Normal birds wait until their full clutch is laid before they begin to incubate them. In this way all the young come out at the same time and grow up at the same rate. A winter parent owl can afford no such luxury and must begin incubating the eggs immediately upon laying (they can lay up to 6 eggs, but usually hold it to two or three) to keep them from freezing. The young emerge in sequence after each has completed its 30-35 day incubation and the youngest arrival must compete with its older larger siblings at feeding time.  Should the cruel hand of nature deal out a skimpy crop of mice, the older owlets will engage in sibling-icide upon the younger family members in order to stay alive. If the mouse crop is robust, then all owlets will thrive. This is a stark form of high risk life insurance that puts sibling rivalry in a whole new light.

  I am happy to report that my local family of Great Horned risk-takers has entered this spring season with a brood of healthy owlets in tow.  The pair took over a large Red-tailed Hawk nest high atop a sturdy oak and they have weathered all that the weather demons have hurled upon the landscape.

  I approached their lair a few days ago and discovered that my approach did not go un-noticed. One of the parent birds was perched nearby (look here). It nervously shifted about from tree to tree and occasionally issued a loud worried “Wonk” call. Knowing full well that these sizable predators are active nest defenders and can pack a wallop with their talons, I kept an eye on this bird during the entire time I was in the vicinity of the nest tree.

  The nest itself is a large twiggy affair nestled in a crotch about 50 feet from the ground.  There were two fluffy young peering out over the edge (look here – the second one is peeking up over the edge on the right hand side). I would estimate them at over a month old because of their size and the fact that an adult is no longer on top of them (there is simply no room).

  Directly under the nest platform, the ground is speckled with whitewash and pellets. After a month of feeding, things can get pretty messy around an owlery with stuff coming out of both ends of the resident birds.  Just to clarify things, let me remind you that whitewash is actually the chalky “pee-poop” that comes out the back end and the pellets are the regurgitated hair/bone packets that come out the front end.

  Each and every meal results in a pellet of undigested bones, hair, whiskers and toenails after a 6-10 hour digestion period.  Even a cursory glance at the pellet contents relays the story of an abundant food supply.  Most of the pellets contained the skulls and limb bones of Meadow Voles (look here and you can see the bony remains of several animals).  Some of them contained larger bone fragments (see here) which turned out to be the mortal remains of a Cottontail Rabbit (based on the distinctive skull cap from that animal seen here).  It somehow seems fitting that the Easter Bunny ends up as an egg-shaped hairball.

  Not wanting to tempt fate, I quickly moved away from the nest site and left the guardian owl and her young to peacefully ponder their own pellets. The parent birds will continue to feed their owlets for another three to four weeks, but the crew will soon abandon this nest.  The owlets spend their last several weeks wandering about the nearby tree limbs- climbing about like tufted monkeys until developing their full flight abilities. I suppose you could say that they will be branching out at this crucial stage, but that would be a cheap pun.  

Older Posts »

Powered by WordPress