Water Resources Special Projects Page 2

MONITORING PROGRAMS FOR MARINE WATERS OF SHELL KEY PRESERVE The Pinellas County Board of County Commissioners through the Pinellas County Department of Environmental Management, Division of Environmental Lands, manages the Shell Key Preserve. The Resource Management Component of the Shell Key Preserve Management Plan calls for a detailed inventory and assessment of the area's natural and cultural resources.
The Water Resources Management Section (WRMS) has developed monitoring programs to contribute to the Resource Management Component of the management plan. The monitoring components are comparable to ongoing monitoring initiatives being undertaken throughout the Tampa Bay estuary. The programs include: water quality/clarity, fish and invertebrate monitoring, and seagrass assessment.
1) Water Quality Monitoring Five fixed sampling sites have been monitored monthly since January 2001. Samples are being analyzed for nutrients, chlorophyll-a, total suspended solids, turbidity, Photosynthetically Active Radiation (PAR) , temperature, Dissolved Oxygen, pH, conductivity, and salinity. 2) Monitoring Wildlife Populations - Fish and Selected Invertebrates In April of 2002, a monitoring program will be initiated to target smaller size classes fish (<100mm standard length) and selected invertebrates in the Shell Key Preserve, targeting smaller size classes (<100mm standard length). Samples will be collected bimonthly. Site locations will be randomly selected using a random sampling design. Six habitat types identified in the Shell Key Preserve include mangrove shoreline with seagrass, mangrove shoreline without seagrass, cordgrass lined shore, channels, offshore areas with seagrass, and offshore areas without seagrass. Seines will be used to collect samples in all of these habitats except channels where trawls may be used. The specimens collected will be identified and measured. Water quality data collected will include Hydrolab and Secchi disc depth readings. Sampling protocol will follow that of the Fisheries Independent Monitoring (FIM) Program of the Florida Fish and Wildlife Commission. In the future, County staff will consider contracting the FIM Program to design a sampling program and to collect abundance data on sub-adult and adult recreationally important fish.3) Monitor Seagrass Coverage Using Transects and Species Surveys In 2001, a program was initiated to monitor fixed transects in areas of the preserve where seagrass coverage has changed (based on 1996 and 1999 SWFWMD data) and in areas of the preserve where seagrass coverage appears to be healthy and static. One transect in the preserve has been assessed three times since 1999 and WRMS will add two more for a total of three to be monitored each year. Also in 2001, the area coverage of dominant seagrass species was determined through an intensive field survey of the preserve seagrass beds. This survey coincided with the shooting of aerial photos by SWFWMD that is currently scheduled to occur every two years. The SWFWMD aerial photos are in turn, used to determine bay-wide seagrass coverage estimates of patchy and continuous beds. Our interior field effort provides a more accurate delineation of existing seagrass beds and will provide species information currently not assessed by SWFWMD. It is anticipated that this intensive seagrass survey will be repeated every 3-5 years to assess trends in seagrass coverage distribution over time.To see the Department Environmental Management Land Management Division's Shell Key Preserve page, click here.To see a copy of the Shell Key Preserve Visitor Guide, click here.
Monitoring in the Feather Sound Area of Old Tampa Bay Nitrogen load reductions to Tampa Bay since the late 1970s have resulted in improvements in both water clarity and quality. These improvements are believed to have led to an increase of seagrass acreage that began in the early 1980s. This increase of about 350-500 acres/year has not, however, occurred in all bay segments. For example, Old Tampa Bay lost 150 acres of seagrass from 1994-1996, and 1,368 acres from 1996-1999. Most losses have occurred along the western shoreline from the St. Petersburg-Clearwater Airport south to the Gandy Bridge. This area is called Feather Sound. Because water quality is an important factor for seagrass survival, a group of bay area scientists hypothesized varying water quality conditions in Old Tampa Bay could explain the loss of seagrass in the Feather Sound area. Staff from the Tampa Bay Estuary Program, Pinellas County Department of Environmental Management (PCDEM), City of Tampa, TBEP, SWFWMD, Janicki Environmental, Inc., and the Environmental Protection Commission of Hillsborough County participated in the design and execution of the monitoring program. Data is collected for water quality factors that are direct measures of water clarity. Water clarity has a direct impact on seagrass survival and growth. Data collected at each site include chlorophyll, turbidity, color, Secchi depth and water clarity (photosynthetically active radiation and transmissivity). Results show water quality is significantly worse in Feather Sound compared to other nearby areas. Results also demonstrate that light limiting water quality factors were all significantly greater in the Feather Sound area. Another aspect of this program is an intensive seagrass monitoring program. The object of this program is to measure changes in seagrass growth, zonation, and distribution over time along a seagrass transects. A large number of small patches of seagrass appeared in the Feather Sound area in 2002 during the first year of the study. There was significant loss of new seagrass patches in this area between 2002 and 2003 with no recovery observed in 2004. Future Work: A second grant was awarded by the Pinellas County Environmental Fund to continue studying the loss of seagrass in Feather Sound. PCDEM will contribute to two of the tasks in this study. Water quality data collected by PCDEM will be used to develop an optical model for the area and PCDEM will lead the task to estimate base flow nutrient loads and storm event mean concentrations at 5 sites in the Roosevelt watershed. This watershed contributes stormwater runoff directly to Feather Sound. For more information contact Mark Flock at: (727) 464-4425. Previous Page

MONITORING PROGRAMS FOR MARINE WATERS OF SHELL KEY PRESERVE

Monitoring in the Feather Sound Area of Old Tampa Bay