Now we know what's in the thick, brown muck that covers the bottom of Old Tampa Bay. Crustacean poop. E-yewww! Might want to wear waders if you decide to walk in Old Tampa Bay and don't want the stuff squishing between your toes.
Ernst Peebles, a professor at the University of South Florida, is leading a team studying the condition of Old Tampa Bay — that's the section north of the Courtney Campbell Causeway — and this week he gave a preliminary report to the Safety Harbor City Commission. It contained some good news — and a fair warning to residents.
Study of the sticky glop has not been completed, but Peebles told commissioners that it appears the muck contains quartz sand, decaying plant particles and "fecal pellets" deposited by tiny crabs and shrimp. In fact, there are so many "fecal pellets" that it indicates "an increase in the amount of zooplankton and/or larval crabs and shrimp," he said.
"What we think is happening, is the area is becoming more productive over time," he said.
That's an unexpected finding, to be sure, because the concern that led to the study was that upper Tampa Bay was dying.
After years of growing concern, the cities of Safety Harbor, Oldsmar and Clearwater teamed up early last year with the Southwest Florida Water Management District and the Tampa Bay Estuary Program to commission a study of Old Tampa Bay.
Oldsmar officials were convinced the northernmost end of the bay was becoming more shallow and unproductive, and that an influx of sediment and pollutants from the Lake Tarpon Outfall Canal might be the culprit. Many who live in the communities ringing the upper bay had been concerned about the thick bottom muck, the dark water color and what seemed to be a decline in the fish population.
But at this midpoint in their yearlong study, Peebles said his team has determined that Old Tampa Bay is not a dead zone and that the muck accumulation is not yet acute. And the tiny animals that live in the bay seem to be thriving. All of that is cause for relief.
Peebles noted, however, that conditions such as poor water quality and accumulation of organic matter on the bottom of the bay are being accelerated by human behavior, including allowing nutrients (such as fertilizers) to flow into the bay.
Such nutrients are a negative, not a positive, in water bodies, because they cause excessive plant growth. Eventually, those nutrients overwhelm natural systems and water quality and animal populations decline.
Peebles said that the Lake Tarpon Outfall Canal, built by man to control flooding in freshwater Lake Tarpon, is "one of many sources that have caused an accumulation of nutrients in Old Tampa Bay over time. If you were to restrict its discharge, it would help."
Oldsmar officials have said so for years.
In answer to questions, Peebles said that the recent increase in the small crustaceans and zooplankton is a positive for now. There is life in Old Tampa Bay. But down the road, there could be a tipping point, he said, if nutrients continue to pour into the bay. Officials who have urged bayside residents to restrict the use of fertilizers on their lawns appear to have been on point.
"This is basically a case where you are seeing something coming," Peebles said. "It's basically fair warning."