SCOTT SHALAWAY It's a real jungle out there for many critters



A pack of wolves stalks, then runs down, an old moose on Michigan's Isle Royale, then devour the victim.
A big bass floats in the murky depths beneath a log along a shady lake bank. When a smaller fish seeks the same cool shade, the bass strikes and swallows.
On the African savanna a cheetah stalks a herd of antelope, isolates one individual, runs it down, and takes it back to her litter.
From atop a skyscraper in one of a growing number of American cities, a peregrine falcon spots a flock of urban pigeons. It picks the straggler that breaks from the group. From above, the falcon folds its wings, plummets with clenched talons, and delivers a dizzying blow. It then snatches the dazed pigeon from the sky and returns to a favorite feeding perch.
Daily scenes
Such scenes occur daily all around the world, yet few of us ever see them. Only on televised nature shows do we get a glimpse of the world of predator and prey.
But on another stage -- our own backyards -- similar dramas unfold every day. The players are different, much smaller and perhaps more familiar, but the script is equally compelling.
These backyard combatants are insects, the most abundant and diverse group of animals on the planet. Though most eat plants, many are predators. The strategies they use to capture prey are remarkably similar to their larger vertebrate counterparts. Or, to be more biologically correct, the strategies of vertebrate predators follow those observed in the insect world.
Insect predators use one of three techniques to capture prey. They may search, chase, and catch it. They may stalk and ambush it. Or they may somehow trap it. If you know what to look for, each of these techniques can be observed in most backyards.
Air attack
Dragonflies, for example, search the air for flying insects. Though usually found near water, in mid-summer dragonflies often wander far from wetlands. I often see them in a pasture near my house, which sits high on a ridge far from water.
Use a pair of binoculars to follow an individual dragonfly and watch how it uses its spiny front two pairs of legs as a net to catch flying insects. Huge compound eyes, which dominate a dragonfly's head, enable it to scan a large area for prey.
Closer to earth, a group of insects called tiger beetles search for food as they scurry along the ground. Anything small enough to handle is fair game for these big-jawed, ferocious, and often iridescently colored beetles. Among the insects that patiently stalk its prey is the familiar and popular praying mantis. Though large by insect standards (up to 3.5 inches long), praying mantises rely on protective coloration to hide them from potential prey. Their bright green body is almost undetectable in the sea of green foliage they inhabit. Like dragonflies, mantises have large compound eyes that give them a wide field of view.
Job-like, mantises wait patiently for another insect to wander by too closely. When it does, the mantis strikes. Its "praying" forelegs extend with remarkable quickness to grab and hold the victim. Then the predator enjoys the fruits of its strategy.
Doodlebugs are one of the trappers of the insect world. These are the larvae of damselfly-like insects called antlions. Upon hatching from its egg, a doodlebug burrows into the ground. They prefer sandy soil. Rather than tunneling straight down, however, the ant lion builds a small pit or crater that might measure and inch or two across. The doodlebug then buries itself at the bottom of the pit and waits for small insects to tumble down the sides. Then it grabs its quarry with its huge mandibles and sucks it dry. Should a victim try to scurry up the mini-crater to freedom, the ant lion tosses grains of sand at the prey to prevent it from escaping.
If you yearn for exciting predator-prey encounters, just study your own backyard. You'll discover that it's truly a jungle out there.
sshalaway@aol.com