Showing posts with label dragonfly. Show all posts
Showing posts with label dragonfly. Show all posts

Monday, October 11, 2010

Wood Recycling

I learn a lot about the natural world just hanging out on the patio grilling burgers and drinking beer. This time of the year, the great Pacific dampwood termites swarm, the fertile winged ones rising into the skies to start new homes in the fallen trees and branches rotting in the deep forest beyond our back fence. Their flight seems strained and clumsy on oversized wings.

I watch a dragonfly dart through the air along a straight path then suddenly switch direction looping back and doing it again along the same path. In one instant it deviates slightly from its chosen path, grabbing a hapless flying termite in midair, and then continuing along the same flight path. A few seconds later, the dragonfly drops the termite, which flutters downward slowly at the pace of a downy feather onto the patio, the gossamer wings no longer beating a struggling flight. I examine the fallen termite and observe that it seems generally intact but is missing its abdomen. This leads me to believe that the dragonfly simply eats the tender abdomen and casts away the remaining hard parts that include the head, thorax, legs, and wings.

Trees fall in the forest; they rot in place, broken down by fungi and termites. Termites swarm and take flight, most ending up trapped in spider webs or snagged in midair by the colorful and graceful dragonflies. This is how wood gets recycled in the natural world. Sure, I’ll have another beer. Barley and hops get recycled, too.

Saturday, August 21, 2010

Season of the Dragonfly

I have lived in the Puget Sound region for almost 20 years. I grew up in southern California on the edge of encroaching suburbia 20 miles east of Los Angeles. Nature was close in a subset of the Puente Hills. The change of seasons was subtle. The rains came in winter turning the hills emerald green then they baked to a soft golden crust in the rainless summer. I knew the names of the plants and animals.

When I first moved to western Washington I did not know any of the signs that marked seasonal transitions. Each year has taught me something new. I have a better understanding of the seasonal signs. I can easily rattle off the names of all the trees growing in the Puget lowland.

Summer here brings many more sunny days than the rest of the country would suspect given the popular myth of gray, rainy Seattle. But our climate here is really a modified Mediterranean climate, with the winter taken to an extreme in rainfall. The summers are generally sunny with moderate temperatures in the high 70s and low 80s (Fahrenheit). The summer days are long at this northern latitude.

Midsummer around my house is Dragonfly season. On sunny days, the largest of dragonflies, the darners patrol the broad open stretches of lawn and garden, catching and devouring smaller insect pray on the wing.

My favorite dragonfly of our garden is the Cardinal Meadowhawk (Sympetrum illotum). It is a brilliant cardinal in color. It usually rests on a conspicuous perch with wings folded downward, a characteristic of the meadowhawks.

 Dragonflies spend the juvenile portion of their life cycle in water as nymphs. Our neighborhood has several small streams that flow from upland areas into Puget Sound, which is only a few hundred feet from our house. These streams are ideal habitat for dragonflies.

Adult dragonflies are the ultimate sky predator, having a head almost entirely covered by a pair of compound eyes and legs that bristle with spikes that form a perfect basket for scooping up smaller flying insect prey.

Dragonflies date back to the Carboniferous period, 300 million years ago, when Meganeuron was cruising the skies with a wing span of 2.5 feet. Imagine seeing that!

















The next seasonal transition is the swarming of the Pacific dampwood termite and the corresponding rapid growth of the European garden spider.  This is a sure sign that the coming of fall is close.