October 31, 2014
October 25, 2014
Box elder bugs are year-round insects but we don’t usually notice them until the “witching season” in late autumn. At that time they gather around the cracks and crevices that will eventually become their winter home. Until freezing temperatures force them to descend into the deepest recesses of their hibernaculum (that’s “scientific” for winter hibernation chamber) they pretty much spend all their time sun-worshiping. The low morning sun is especially relished.
I have a cedar shingled house offering plenty of potential hibernacula. The entire east side is bathed by the rays of the morning sun on early bright fall days. You could call it a Box Elder Bug palace; although I doubt that particular phrase would enter into the realtor’s description should we opt to sell the place as we enter the autumn of our lives.
The Box Elder B’s greet the sun with a collective sigh of relief – clustering into small social clubs where they talk about how much life sucks. As sucking insects this topic is a positive one. In the spring they will emerge to feed on seeds and low plants until the local female Box Elders trees (or occasional maple) come to flower. There they will suck Elder sap and raise new little suckers.
The only question remaining for the next year’s elder Box Elder Bug population is what to call the new Box Elder Bugs they create. Should they be called Box Youngling Bugs or perhaps Box Baby Bugs in order to separate them from the older and wiser winterers? Fortunately this never poses a real problem because the elder Box Elder Bugs die before they can gather into focus groups.
We superior humans, of course, know that this is a stupid question because the plant is called Box Elder not because it is older than the rest but because, um, well … because of… Oh, yes because the wood resembles that of the Boxwood tree and the leaves that of the Elder tree. And we ALL know that Elder trees are guarded by witches and, according to an old European chant (“And I myself an eldern tree”) some are actually witches themselves!
Silly insects, they believed that they were feeding on witches’ blood all summer but were actually taking in fake witches’ blood. As half-wing insects (true bugs are hemipterans), it could devastate the other half of their lives should we let them in on this devastating secret. I for one do not want to listen to the collective sobs of a million Box Elder Bugs through my wall all winter long.
October 18, 2014
The natural world is ripe with imitation. It is the ultimate form of flattery (and self-preservation) to look like something else – especially if that something else is inedible. Take a dry leaf, for example. Only a low life decomposer would even consider a dead leaf as food, so many insects wear a dead leaf costume in order to convince hungry predators to overlook them. Moths are especially prone to this disguise tactic because the structure of their wings lends itself well to such fakery.
On a day when brown windblown leaves were tousling about, I spotted this Geometer Moth clinging to the rough bark of a Red Maple. The adult form of twig-imitating “inchworms,” geometer moths extend this youthful deception to become grown up leaves.
It might seem that such a disguise fails when it is exposed against the dark background of a tree trunk. After all, I spotted the thing from a dozen feet away. But, then again, it had such a good leaf look that I doubt that even a savvy predator would discern this from the millions of other leaves blowing about. This individual had the additional effects of age to enhance its outfit. Multiple tears – not part of the original wing design – gave it the truly authentic worn look of a crackled October leaf.
Because the tears are not genetic parts of the camouflage look, this moth will not pass on these traits to the next generation. Probably the result of a short life of heavy use, they will likely insure that this critter will survive its full short life before succumbing to a natural death from the chills of autumn.
October 13, 2014
Much of the life of Funnel Weaver Spiders involves a waiting game. Instead of pursuing prey like wolf spiders or animated jumping spiders, they spin flat sheet webs and wait for insect prey to walk across the surface. The killer waits inside a special side chamber (the “funnel”) until signaled to emerge by the vibrations generated from tiny feet crossing the web. A quick dash, followed by a fatal bite secures the prey and renders it a meal. When the mating urge is felt, the males abandon their web and go courting – fully realizing in their instinctive little brains that this risky behavior is necessary for the propagation of the species. Ah, the things they will do for love.
Female Funnel Weaver spiders wait within their liars until prospective mates come a knocking. For a male of the species this is a tricky prospect because knocking at any funnel weaver’s door is tantamount to inviting yourself for dinner – as in YOU being the dinner. When that doorway frames a hungry female, about a third larger than you, the danger is even greater. Although no self-respecting spider would admit it, the empty carcasses of dead insects lining the path certainly don’t inspire confidence. So, before he can get down to business, the suitor must convince the female that he is not a meal but a mate.
He will dance about and wave his legs to signal manly intentions. Pedipalps – specialized male appendages to either side of the jaws – are moved to and fro like an airline worker guiding a landed jet to its gate. All this is intended to convince the potential Mrs. that he is a virile eight-legger and not a six-legged juice box. Once convinced, the female will allow her suitor to advance and begin his masculine task. To say the least spider foreplay is a creepy affair, but that which follows is fascinatingly boring.
I witnessed this drama taking place in my yard last week. A sizable female weaver (see first photo), who had maintained a funnel bridging the gap between an old barrel hoop and the siding of the house, received a late afternoon visitor. He ably subdued her into taking a passive legs-up pose but never let his guard down during the process which followed. While still slowly waving one of his pedipalps in the air he carefully engaged the other on her tender undersides.
The tips of the pedipalps are saucerlike with the inner surface of each sporting a black coiled organ called an embolus. They are maneuvered down to the female’s genital opening and the tip of the embolus inserted within. Then, the male pumps his semen into the female .To carry the airline analogy one step further, this process is more like fueling a jet and just about as exciting. One big difference here is that the process takes many hours (six hours or more in some cases!). And that, my dear readers, is not a spectator sport. I left to watch some corn growing across the road.
The male made his escape by nightfall (at least he was gone by the time I checked back much later). He will live to inseminate several more females before dying with a smile on his eight-eyed face. Females will also mate with several more males if they are given the opportunity. In the case of my yard spider, she retreated to the space under the siding and never appeared again. This could have been her third suitor for all I know. Unseen under the shingle, she would have laid several lens-shaped egg sacs containing 50-200 eggs which will pass the winter.
When the young emerge in the spring they will likely scamper over the desiccated remains of their mother who died peacefully in place after laying her eggs. There is much creepiness in the spider world but then again it is all about perspective isn’t it?
October 4, 2014
It was only after the mink disappeared under a tree root that I re-directed my attention to a trio of Mallards across the river. They were clear enough to see, but in the world of nature study Mallards are not normally on the top of the list. This is not a good thing, but it is a thing because familiarity breeds, if not contempt, at least complacency. These fine fowl were standing unsurely on a submerged branch as the current of the swollen Huron River rushed past them.
Backlit by a strong morning sun, they were on high alert with nervous heads bobbing atop extended necks. Actual wild mallards, not frumpy farm fowl, they were ready to bolt at the sequential exposure to a mink and man! Fortunately they hung around for a frantic minute before exploding into flight.
These male birds were perfect examples of the teenage type (due to plumage and not erratic unexplainable behavior). Juvenile birds offer some interesting plumage combinations as they transform into adulthood via a time-honored schedule. It is not a random process. Because it occurs relatively quickly, however, it is a minute phase of the natural year that is often overlooked.
Earlier in the month the ducks bore the brown mottled plumage of youth and were now in the late September mode of wardrobe change. At this stage the mottled breast feathers are mostly replaced by the deep russet tones of drakehood and most of the back and shoulder feathers have already converted over to light gray. It will take a while before they attain the distinctive black curly feathers on their fully mature bottoms, but they already exhibit a manly looking yellow bill.
The green portion of the head, that part which gives the species the common name of “Greenhead,” is but a simple crescent lying between eye and beak as of early fall. As the season progresses, this patch migrates from front to back until the entire head becomes iridescent green by winter. You will see some Mallards which have an overall spotty green head (“scruffy” by some definitions) and these would be the adult drakes recovering from their late summer eclipse plumage. Adult Mallards undergo two molts per year.
The subject of molting is a big one in the bird world. For these juvenile males, the act of changing feathers involves a heavy physiological workload. Being mostly protein, feathers make up around 1/3 of the entire body protein of the animal. Therefore, feather-growing requires a substantial intake of protein rich foods. Add to this burden the need to put on an extra load of fat for migration and you have birds that can afford little time for leisure.