What is Happening to the Dolphins Near Piney Point?

We’re monitoring the dolphin community near Port Manatee for impacts from the Piney Point discharges of polluted water

If you’ve been following the news lately, you’ve probably heard about the discharges of phosphorous and nitrogen polluted waters from Piney Point, an abandoned fertilizer mine in Manatee County near the coastline of lower Tampa Bay.

The plant is located in an environmentally sensitive area, near aquatic preserves at Bishop Harbor and Terra Ceia Bay. According to news reports, at least 173 million gallons of polluted water have been released so far, with discharges of the remaining 300 million gallons continuing in Tampa Bay.

The CZS-SDRP has been studying the dolphin communities along Florida’s central and southwest coast since 1970.

The area currently receiving the discharged water is beyond the northern end of our Sarasota study range but studies we conducted throughout Tampa Bay with National Oceanic and Atmospheric Administration (NOAA) support 1988 to 1993 demonstrated the existence of another resident community of dolphins immediately north of, and slightly overlapping, the Sarasota range.

That dolphin community is essentially centered on the pollutant discharge site at Port Manatee, near Piney Point.

NOAA — the agency responsible for enforcing the Marine Mammal Protection Act and protecting wild dolphins — recently encouraged us to extend our regular Sarasota Bay dolphin-monitoring program to include the community of dolphins closest to the Piney Point discharge site.

Since April 5, we’ve been conducting photographic identification surveys between the Sunshine Skyway Bridge and Cockroach Bay, centered on the discharge site. We are trying to identify:

  • Which dolphins are being exposed to the highest concentrations of discharged waters;
  • How their distributions may have changed in response to the discharges;
  • Whether dolphins are having respiratory issues, exhibiting abnormal behavior or developing unusual skin conditions.

If the animals have left the area, we will also want to determine where they went.

Preliminary indications are that dolphins are not using the waters near Port Manatee in the same numbers and to the same extent as they did during our earlier surveys. We have found them in smaller numbers and mostly more than two miles away from the discharge site. Preliminary analyses of photographs have found two dolphins we first identified in the area in 1990, and another seen on two days that was first identified in 2009.

As a group long-dedicated to monitoring the health and conservation status of wild dolphin populations, we wanted to help even though NOAA is currently unable to provide funding for this monitoring work.

Fortunately, we’ve been able to receive approval from one of the main funders of our Sarasota Bay dolphin monitoring program to temporarily shift some of the funding we receive to be able to accommodate an increase in the range of our study area. Other dolphin research programs to our north — including one at Eckerd College and the Dolphin Ecology Project — are also surveying potentially impacted waters.

I’d like to thank the Charles and Margery Barancik Foundation for allowing us the flexibility to respond to this situation so that we may monitor the impacts on dolphins living in the wake of this long-term, man-made problem.

If you’d like to help support our work, you can make a donation online at www.SarasotaDolphin.org/donate.

As always, I thank you for your support and for caring about wild dolphins.

Randy Wells