FLORENCE — Lauderdale County and two of its watersheds are among the most biologically diverse places not only in Alabama but the world, according to a biologist.

Stuart McGregor, a biologist with the Alabama Geological Survey, said of the approximately 840 known species of mussels in the world, 93 of them live in the Tennessee River valley, and 80 of those, or 11 percent, are found in the Muscle Shoals area.

Speaking Tuesday night at a meeting of the Shoals Environmental Alliance, Stuart said Cypress and Cox creeks in Lauderdale County are generally healthy, though they face the same threats that other watersheds face: poor land use practices.

“I would give Cypress and Cox creeks a seven or eight on a scale of one to 10,” he said. “That’s better than most.”

McGregor, who grew up in Florence exploring the abundant water sources in the county, described a varied and seldom seen array of fish and aquatic life found here. Hellbenders, crayfish, snails and darters are more common than most people realize, he said.

Cox Creek is especially diverse for its size, he said, in part because there has not been much high-impact development near its banks. To maintain its biodiversity, the borders of the creek should be closely monitored and protected.

Members of the Shoals Environmental Alliance (SEA) are concerned that two city landfills along Cypress Creek, one of which was closed in the 1980s, pose serious threats to the health of Cypress Creek. Several members have documented discolored and odorous discharges from springs near the current landfill and from the landfill itself.

Nancy Muse, vice president of SEA, said they also are concerned about the construction of a Wal-Mart off Cloverdale Road that could create nonpoint pollution problems from petroleum-based runoff from cars in its parking lot.

“Development in that area could impact the biodiversity in that area even if all the state and federal regulations are followed,” she said.

Charles Rose, president of the group, said its goal is to keep the creeks and other areas as healthy as possible.

Robert Palmer can be reached at 256-740-5720 or robert.palmer@TimesDaily.com.