For Hometown News
The St. Johns River Water Management District's Lake George gizzard shad harvest removed more than 9,000 pounds of phosphorus and 28,000 pounds of nitrogen from the lake in Volusia and Putnam counties, part of the St. Johns River system.
Removing gizzard shad from Lake George will help meet the necessary downstream nutrient loading reduction for state water quality standards and reduce the severity of algal blooms in the lower St. Johns River.
The gizzard shad harvest took place from June 3 through Sept. 6, and exceeded the district's expectations by removing 1.17 million pounds of the fish from Lake George, which removed thousands of pounds of nutrient pollution from the lake. Removing large numbers of shad from a water body removes the nutrients contained in the fishes' bodies.
Gizzard shad feed on algae on the bottom of the waterway, stirring up sediments and clouding the water. Shad excrete nutrients back into the water, recycling nutrients from the bottom that feed more algae. Thus, by removing the fish, another 31,000 pounds of phosphorus and 93,000 pounds of nitrogen will not be released into the lake to impair its water quality.
The $694,000 project was funded with a 2012 legislative appropriation, which dedicated $5.6 million to St. Johns River restoration projects.
Gizzard shad are a native fish found in most Florida waters and account for 5 to 20 percent of the total fish population in healthy Florida lakes. However, in nutrient-rich, algae-dominated lakes, gizzard shad proliferate and can account for more than 90 percent of the total fish population.
The district hires commercial fishing vendors to net gizzard shad. Sport fish caught in nets during the harvests are immediately released.