In the middle, they are immobilized and defenseless, and seemed to have a single-minded focus on their transition. But at both those stages, the insects’ amazing eyes and high-speed maneuvering help them survive. At the beginning of a dragonfly’s life, it is threatened by fish. Hours pass when the ferocious predators are vulnerable, unable to move, easy prey. Extra hemolymph, the liquid which is pumped into veins in the wing to shape them, drains out of a Rusty Snaketail as it prepares for flight. Dragonflies must extract themselves from their shell and then pump “hydraulic fluid” into their wings to straighten them out, then let the wings stiffen enough to create lift. Their gills are located in the same internal chamber in their rear-ends, and its muscles can either pump water over them to get more oxygen, or push the insect forward at a speed of about 4 inches per second.įinally, when it is time to mate, the underwater bugs are born into the atmosphere, and only after shedding their aquatic exoskeletons. In that stage, the insects are expert hunters, ambushing other aquatic creatures, gobbling up other insect larvae, tadpoles, and even minnows.Ī dragonfly larvae’s most lethal adaptation is “liquid propulsion,” which really means they move around by squirting water out their butts. Lethal larvae A nymph from the Darner family, one of the most effective aquatic predators.ĭragonflies are unique in their excellence at hunting both in the air, and underwater.ĭuring the first part of their lives, which can last from a couple months to several years, a dragonfly grows from an egg to a hard-shelled nymph on the bottom of lakes and rivers.
Instead, the banks hosted a bonanza of dragonflies going through the biggest change of their lives. Then we discovered they were actually abundant - just not in the air. When it’s warm, they are in top form and can pick off other insects easily, fueling their flight. Those were discouraging conditions to look for cold-blooded dragonflies. When I met up with them in the morning at Stevens Creek Landing, east of Rush City, the temperature was in the 50s and the sky was overcast and threatening to rain. One late May day, we headed to the upper river to canoe and hopefully see some interesting species. Croix, as well as the Red Lake Peatlands of northern Minnesota. I’ve tagged along with them previously around Marine on St. This curiosity is how I connected with some members of the Minnesota Dragonfly Society: Mitch Haag, Curt Oien, and Ron Lawrenz. I always want to know what I’m seeing, if it’s common or rare, what its presence says about the river, what its life is like, and how it fits into the whole ecosystem.
Their mix of ferocity and friendliness is intriguing, and it seems like they come in endless combinations of sizes and colors. Croix and its tributaries, resting and riding along. Many times, dragonflies have landed on my canoe or kayak while I float down the St. Fierce and friendly Cobra Clubtail ( Gomphurus vastus) Higher oxygen levels in the atmosphere at that time helped the hawk-sized insect grow so large. Dragonflies’ unmatched flying abilities, remarkable eyes, and other adaptations, make them almost perfect predators.ĭragonflies were some of the first insects to evolve about 300 million years ago, when a relative with two-foot wingspans hunted humid jungles. Kids are especially enraptured by the bulging eyes, jutting jaws, and aerial antics. They are big, colorful, and ferocious, and can capture anybody’s curiosity. They are acrobats In the air, the envy of helicopter pilots, able to fly fast and turn sharply, hovering and flying sideways and even backwards as they pick off their insect prey mid-air. Croix and its exoskeleton perches on the banks of the river as its wings harden for flight.ĭragonflies are defining features of summer days on the St. A Skillet Clubtail ( Gomphurus ventricosus) which recently emerged from the St.
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