Thursday, March 15, 2007

Death of a Brook Trout Stream

Via The Buffalo News

Death of Ledge Creek gives birth to cynicism
By John Opera
Updated: 03/13/07 12:43 PM

Tucked away in the northeast corner of Erie County is a small tributary of Tonawanda Creek called Ledge Creek. A stream survey conducted in 1920 by the Buffalo Society of Natural Sciences described Ledge Creek as a “short stream about 4 miles long arising in the region just northeast of Akron and flowing northerly. A beautiful brook flowing partly through swamp and partly through open farmland.”

The survey goes on to describe the water at the sampling site as “deep, cool and well-shaded.” The number of fish species found there includes an impressive list of darters, game-fish and minnows, however, one species seems to leap out from the list — brook trout.

In the language of ecology, brook trout are known as an indicator species. They will survive and reproduce only in water that is relatively cool, unpolluted and saturated with oxygen. Considering the fact that Ledge Creek was

never stocked, it is very likely the brook trout found there in 1920 were direct descendants of the earliest trout populations established after the end of the Ice Age.

My first encounter with Ledge Creek occurred in 1978. I thought it might prove interesting to have the high school ecology class I taught at the time study the creek and compare the students’ results with the data collected more than half a century earlier.

I anticipated changes, but nothing could have prepared us for the shock we were about to experience. Upon arriving at the sampling site, we found the creek was gone. All that remained of the ecosystem were a few stagnant pools smelling of sulfur and a dry creek bed. The only life we found in the creek were bloodworms. Like Brook Trout, bloodworms are an indicator species, but their presence reflects severe pollution and oxygen deprivation.

For the remainder of the school year, Ledge Creek became a topic for discussion and study. Students found that government agencies were polite, but the information gleaned from them seemed vague and inconclusive. Eventually, the case of Ledge Creek became a kind of ecological X-file kept active by myself and a few zealous students.

Today, considering the problems gnawing at our fragile planet, the death of a small brook may seem inconsequential. But when I think of Ledge Creek, I am reminded of a diminutive ground orchid called the small whorled pogonia found in the woods of New Hampshire. It flowers briefly in spring, then disappears and may lie dormant for 20 years before reappearing. Its role in the complex fabric of forest ecology has never been established, but its very presence suggests a purpose.

We may never know what benefits Ledge Creek bestowed upon adjacent ecosystems, or how its demise may have affected the quality of our own lives.

I’m retired now, but I still go back there occasionally, looking for clues. Sometimes there is water in the creek, but it is mostly runoff — a witch’s brew of snow-melt, lawn fertilizer and pesticides.

I often think of my students sifting incredulously through the dry bones of the creek, looking for some sign of life. I remember the questions I could not answer, and the angry comments hurled at the nameless adults responsible for the creek’s untimely death.

The real tragedy of Ledge Creek might have been the cynicism bred there that morning years ago.

Via The Buffalo News