Highway, development imperil Mattawoman Creek, report warns

While bass are still plentiful, the creek seems to be losing its attractiveness to migratory fish seeking clean fresh water upstream to spawn in the spring. The Mattawoman is less productive now than it was in the 1970s, when the area was much less developed, says Margaret McGinty, a biologist with the state Department of Natural Resources.

Sampling done last year found "a definite decline" in places where fish had come to lay their eggs in spring, according to a DNR report. Yellow perch eggs were seen, but white perch and river herring were scarce.

Those fish are dwindling virtually everywhere, so it's hard to tell whether the decline in the Mattawoman stems from conditions in the creek or other places the fish roam, in the Chesapeake Bay and Atlantic Ocean.

But for whatever reason, the number of fish tends to diminish in streams where 5 percent or more of the watershed is covered in pavement or rooftops, the state report says. The share of the Mattawoman watershed covered by development is nearly twice that, roughly 9 percent, and future development could extend pavement across 15 percent or more.

Biologists have noted a long-term decline in dissolved oxygen in the creek, with levels occasionally dropping in recent years below what's needed for fish to live.

Jim Long of the Mattawoman Watershed Society, who has been sampling fish eggs in the creek every spring, says it was discouraging to find far fewer last year.

"Mattawoman's on the brink," Long said.