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Here will be dragons

 

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Living near water offers diverse benefits to birders, boaters and bathers—the last not so much at Farrar Pond, where swimming is prohibited. Also costs; a major one, with shallow ponds and marshy edges, is the rapid breeding therein of contagion-bearing whining bloodsuckers.

Lao Tzu reminds us that when any force or movement becomes powerful, its counter also manifests. The same swampy water that attracts fecund mosquitoes and other unwelcome winged pests supports a varied population of creatures that thrive on their eggs and larvae. Baby turtles, tadpoles and fish all favor this high-protein food source. Among the most aggressive, taking tadpoles and minnows as well as smaller prey, are the naiads—obligate aquatic larvae—of order Odonata (“toothed ones”): dragonflies and damselflies. As top predators among aquatic arthropods, they rival the enormous but more delicately built water scorpions (Renata sp.):

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Naiads, usually concealed in the submerged jungle, may be seen as they cautiously emerge to split and dry on a reed or other protrusion, lifting themselves toward adulthood. Wings dry, they become fierce and effective aerial hunters, clearing the air of more undesirable insects than any bug-zapper ever could. Elegant in flight or at rest, they tolerate the close approach of slowly moving humans, and will even land on us to chew down a bug that may be almost as large as themselves. Stand in a sunny meadow with a finger pointed skyward, and they may come to perch between hunting forays.

Though themselves a rich meal and often brightly colored, iridescent or reflective, odonates are relatively safe in flight: their unpredictable jerky motion and panoramic compound vision

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(note solar and camera-flash reflections from patches among thousands of hexagonally close-packed ommatidia)

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make them difficult for a swooping bird to track and intercept. And though considered by some a canard, their ability to operate fore-wings independently of those aft

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gives them aerial agility and multi-axis maneuverability exceeding even the hummingbird. Nonetheless, a close inspection of dragonfly hunting grounds shows how much they are themselves hunted, with beaked-off wings lightly scattered everywhere. Nor can their substantial translucence defend against that of of a common near-surface hazard;

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unlike their artificial brethren, these do not wield a wire-cutter.

At rest, they are more vulnerable, and to a broader range of predators. So beyond transparency, various camouflage strategies (like disruptive coloration, substrate mimicry and countershading) come into play. Adding species self-identification cues, the resulting shows of color are exceptional even among insects. A few more in situ examples of the hundred-plus found hereabouts, guiding the eye to subtle complexity, grand recursion and even enlightenment:

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And how closes the cycle of life? With eggs. In a seldom-seen dance, this female hovers over a half-submerged nymphaea pad, repeatedly dipping her tail to wash eggs into the smaller pool. The success of this hands-off approach to breeding will make itself known come spring.

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(For another tactical approach, see this entry in Mary Holland’s excellent “Naturally Curious” blog.)

Short video here: