5.0 MONITORING AND SUCCESS EVALUATION

5.1 PURPOSE AND IMPORTANCE OF MONITORING

The results of environmental monitoring programs are important to a wide range of interests associated with Lake Tarpon - fishermen and recreational user groups, lakefront residents, resource managers, scientists and engineers, politicians and private citizens. Examples of information needs met by monitoring are listed below (National Research Council, 1990).

Many environmental monitoring programs lack a clearly articulated purpose and objectives. This lack of focus often results in less than cost-effective use of available funds as well as data gaps and unanswered questions. Monitoring programs need to be properly designed, and monitoring methods appropriately applied, if they are to meet the multiple expectations of all those who rely on the information generated. Although most monitoring programs are technically sound, it is their overall design and institutional context that limits the usefulness of the information that results. Therefore, sound program design and implementation often depend on the following factors (National Research Council, 1990).

The remainder of Section 5.0 discusses the development of appropriate and achievable monitoring objectives which support the long-term implementation of the Lake Tarpon Drainage Basin Management Plan. The detailed protocols for each of the recommended monitoring programs associated with each of the key management issues facing Lake Tarpon are described in the Task 3.2.11 Interim Report.

5.2 DEVELOPMENT OF MONITORING OBJECTIVES

In developing specific monitoring objectives, it is critical to establish a hierarchical structure to the planning and program development process. The development of appropriate and achievable monitoring objectives for Lake Tarpon must be clearly linked to, and driven by, the defined management issues and goals adopted by the LTMC. For each of the adopted goals, there must also be defined criteria by which attainment of a given goal can be measured. These measures are herein referred to as "targets," as discussed in Section 4.1 above. Since targets are specific units of measure that define progress towards a management goal, all targets must be linked to, and supported by, one or more monitoring objectives. Conversely, all monitoring objectives must cleary support a target. The planning hierarchy of the monitoring program development process can be summarized as follows:

Management Issue

Ż

Management Goal(s)

Ż

Level-of-Service Target(s)

Ż

Monitoring Objective(s)

Ż

Monitoring Program

In the sub-sections that follow, specific targets and monitoring objectives addressing the adopted management goals are proposed, and the rationale for each are discussed.

5.2.1 Water Quality

Under the targets developed for the Water Quality issue twelve specific monitoring objectives are proposed, with some targets being associated with more than one monitoring objective. The rationale for each proposed monitoring objective is discussed below.

Target 1: Maintain a mean annual chlorophyll-a concentration of 14ug/l or less.

Objective 1: Measure monthly in-lake chlorophyll-a concentrations.

Rationale: The amount of phytoplankton biomass, measured as chlorophyll-a, serves as an integrator and indicator of lake trophic conditions. High mean annual chlorophyll-a concentrations usually indicates excessive algal growth. With regard to available and comparable water quality data, the best continuous record exists for the parameter of chlorophyll-a. Furthermore, the collection and measurement of chlorophyll-a samples is already programmed into the existing monitoring program.

Target 2: Maintain a mean annual multi-parametric TSI value of 55 or less.

Objective 2A: Measure monthly in-lake TN and TP concentrations.

Rationale: Nitrogen (N) and phosphorus (P) are the primary nutrients required by plants for growth and reproduction. In excessive concentrations, N and P can cause nuisance algae blooms. The measure of all chemical forms of these nutrients (total N and P, or TN and TP) in the water column is a measure of the algal growth potential, and thus is an important indicator of trophic state. TN and TP concentrations are two of four parameters used to calculate a multi-parametric TSI value, with chlorophyll-a and Secchi disk depth being the other two. While the collection and measurement of TN and TP samples is programmed into the existing monitoring program, previous monitoring data are of limited value due to problems with laboratory detection limits and other analytical problems. This situation has, however, been recently corrected.

Objective 2B: Measure monthly in-lake Secchi disk depths.

Rationale: Secchi disk depth serves as a simple measure of lake water clarity. The degree of water transparency is one of the most important attributes of water. Water transparency allows the penetration of light, which supports life through the photosynthetic process. The degree of water transparency has a direct impact on the growth and distribution of submerged aquatic vegetation. Water transparency also allows organisms with visual organs to see in order to search for food and shelter. Water transparency can be affected by suspended organic (e.g., algae) and inorganic (e.g., silt) matter in the water column, as well as tannins and dissolved substances. Secchi disk depth is one of four parameters used to calculate a multi-parametric TSI value. While the measure of Secchi disk depth is already programmed into the existing monitoring program, previous monitoring data are of limited value due to inconsistencies in field methodology. This situation, however, has recently been corrected.

Target 3: Reduce current annual TN and TP loads from external sources by 15% and 21%, respectively.

Objective 3A: Estimate mean annual loads of TN and TP to Lake Tarpon from tributaries and nonpoint source runoff.

Rationale: It is possible to estimate external TN and TP loads from tributaries (e.g., Brooker Creek) and nonpoint source runoff through direct measurement at points of discharge to the lake. Since tributary discharges plus nonpoint source runoff represent approximately 59% and 27% of the total annual external TN and TP loads, respectively, and since these loads are both measurable and manageable to some extent, long term trends in these loading sources should be monitored to evaluate the effectiveness of load reduction strategies.

Objective 3B: Estimate mean annual loads of TN and TP to Lake Tarpon from groundwater seepage.

Rationale: Few site-specific data exist regarding the magnitude and timing of groundwater inputs to Lake Tarpon. Modeling results indicate that approximately 10% of the total annual TP load is contributed by groundwater seepage, however, these estimates have not been directly validated with field data. Although groundwater contributions to Lake Tarpon hydrology have recently been estimated (Upchurch, 1998), ongoing monitoring is needed to determine long-term trends in this loading source.

Objective 3C: Estimate mean monthly loads of TN and TP to Lake Tarpon from atmospheric deposition.

Rationale: It is possible to estimate external TN and TP loads from atmospheric deposition through direct measurement. Based on measurements taken from sites in the Tampa Bay region it is estimated that atmospheric deposition accounts for about 25% and 56% of the total annual external TN and TP loads to the Lake Tarpon, respectively. Measurements from samples collected in the Lake Tarpon basin are needed to better estimate local conditions and loading rates. Although this loading source is not considered to be directly manageable at this time, long term trends should be monitored to determine the relative importance of this source, as well as the effectiveness of regional air quality programs.

Target 4: Annually calculate current water and nutrient budgets for Lake Tarpon.

Objective 4: Estimate the mean monthly mass of TN, TP, and water volume discharged from Lake Tarpon.

Rationale: The estimation of mean annual TN, TP, and hydrologic loads discharged from the lake combined with estimates of mean annual loads entering the lake are needed to calculate lake water and nutrient budgets. Estimates of external loadings from tributaries, nonpoint sources, atmospheric deposition and groundwater are measurable and are addressed in separate monitoring objectives above. To balance a water/nutrient budget, direct measurement of outflows from the lake are needed. Annual estimates of loads leaving the lake will enable the calculation of net loadings into the lake, loads which should be related to mean annual in-lake chlorophyll-a concentrations and TSI values. The Lake Tarpon Outfall Canal provides a convenient structure for measuring flow and collecting water samples; however, instrumentation for accurately measuring stage and flow volumes need to be installed at the outfall structure to meet this monitoring objective.

Target 5: Maintain Class-III water quality standards for dissolved oxygen, pH, specific conductance and chlorides.

Objective 5A: Estimate the monthly frequency, duration, and magnitude of bottom dissolved oxygen concentrations in Lake Tarpon that fall below regulatory minima of 5.0 mg/l.

Rationale: In addition to phytoplankton biomass, the concentration of dissolved oxygen in the deepest portions of the lake is often a good indicator of overall lake water quality. Any dissolved oxygen concentrations below 5 mg/l are in exceedance of Class-III State water quality standards, and may result in fish kills and other adverse impacts on biota.

Objective 5B: Estimate for Lake Tarpon and the outfall canal: 1) the monthly trend in pH; and 2) the frequency, duration, and magnitude that monthly pH varies by more than one unit above or below natural background levels.

Rationale: A rapid or large change in lake pH may have severe adverse effects on lake biota. In 1990 a significant drop in pH (e.g., >2 pH units) was observed during the summer following an accidental lake level drawdown. Since then pH has continued to rise. The cause(s) of this pH trend, nor the impacts of these changes on lake biota, is not known. Ongoing monitoring is needed to determine the importance and possible causes of pH fluctuations in Lake Tarpon.

Objective 5C: Estimate for Lake Tarpon and the outfall canal: 1) the monthly trend in chloride concentration; and 2) the frequency, duration, and magnitude that monthly chloride concentrations exceed background level by 10% or more.

Rationale: A rise in mean chloride concentrations above existing and historical levels (between about 200-250 mg/l) may have adverse effects on lake biota. Although mean annual lake chloride levels have remained essentially the same since 1988, future increases of in-lake chloride concentrations are possible due the proximity of the lake to saltwater. If a trend of increasing lake chloride levels is detected, it may be an indicator of potential degradation to existing lake flora and fauna.

Objective 5D: Estimate for Lake Tarpon and the outfall canal: 1) the monthly trend in specific conductance; and 2) the frequency, duration, and magnitude that monthly specific conductance exceeds 1,275 µmhos/cm.

Rationale: Increases in specific conductance, like chlorides and pH, may adversely affect in-lake biota and be indicative of causative factors of the observed conductance trends.

Target 6: Attain an 80% TSS load reduction for all permitted MSSW facilities within the Lake Tarpon drainage basin.

Objective 6: Estimate the number of permitted MSSW facilities in the Lake Tarpon drainage basin attaining an 80% TSS load reduction.

Rationale: Site plans and design specifications should exist for all permitted MSSW facilities in the Lake Tarpon drainage basin. Therefore, a detailed inventory of these facilities and an assessment of their compliance with the required performance standards could feasibly be completed over a period of time. Retroactive enforcement should be based on this information.

The goals, targets and monitoring objectives related to the Water Quality management issue are summarized in Table 5-1 below.

Table 5-1. Goals, targets and monitoring objectives for the Water Quality issue.

Goal(s)

Target(s)

Monitoring Objective(s)

The lake should be managed such that good water quality is assured.

1. Maintain a mean annual chlorophyll-a

concentration of 14ug/l or less.

1. Measure monthly in-lake chlorophyll-a concentrations.

 

 

2. Maintain a mean annual multi-parametric TSI value of 55 or less.

2A. Measure monthly in-lake TN and TP concentrations.

2B. Measure monthly in-lake Secchi disk depths.

 

 

3. Reduce annual TN and TP loads from external sources by 10%.

3A. Estimate mean annual loads of TN and TP to Lake Tarpon from tributaries and nonpoint source runoff.

3B. Estimate mean annual loads of TN and TP to Lake Tarpon from groundwater seepage.

3C. Estimate mean annual loads of TN and TP to Lake Tarpon from atmospheric deposition.

 

 

4. Calculate a current water and nutrient budget for Lake Tarpon on an annual basis.

4. Estimate the mean annual mass of TN, TP, and water volume discharged from Lake Tarpon.

 

 

5. Maintain Class-III water quality standards for dissolved oxygen, pH, specific conductance and chlorides.

5A. Estimate the monthly frequency, duration, and magnitude of bottom dissolved oxygen concentrations in Lake Tarpon that are below 5.0 mg/l.

5B. Estimate for Lake Tarpon and the outfall canal: 1) the monthly trend in pH units; and 2) the frequency, duration, and magnitude that monthly pH units vary by more than one unit above or below natural background levels.

5C. Estimate for Lake Tarpon and the outfall canal: 1) the monthly chloride concentration; and 2) the frequency, duration, and magnitude that monthly chloride concentrations exceed the background level by 10% or more.

5D. Estimate for Lake Tarpon and the outfall canal: 1) the monthly trends in specific conductance; and 2) the frequency, duration, and magnitude that monthly specific conductance exceeds 1,275 µmhos/cm.

 

 

6. Attain an 80% TSS load reduction for all permitted MSSW facilities in the drainage basin.

6. Estimate the number of permitted MSSW facilities in the Lake Tarpon drainage basin attaining an 80%TSS load reduction.

5.2.2 Aquatic Vegetation

Under the targets developed for the Aquatic Vegetation issue four specific monitoring objectives are proposed. The rationale for each proposed monitoring objective is discussed below.

Target 1: Maintain the areal coverage of desirable, endemic submerged aquatic vegetation (SAV) at 600 acres or more (>24% of the lake bottom area).

Objective 1: Estimate the status and trends in areal coverage, spatial distribution, and species composition of desirable, endemic submerged aquatic vegetation every two years.

Rationale: No quantitative survey of the coverage of submerged aquatic vegetation has ever been performed in Lake Tarpon. Given the importance of submerged aquatic vegetation to the overall ecology of the lake, quantitative monitoring is needed to assess status and trends in areal coverage, spatial distribution, and species composition on an annual basis. A key management principle for Lake Tarpon will be to drive the system away from phytoplankton dominance, and towards macrophyte dominance, with respect to primary production. Monitoring the status and trends in desirable, endemic submerged aquatic species is warranted to determine progress towards this overall management goal.

Target 2: Limit the areal coverage of hydrilla to 100 acres or less (<4% of the lake bottom area; <17% of the SAV areal coverage target).

Objective 2: Estimate the status and trends in areal coverage and spatial distribution of hydrilla every two years.

Rationale: Currently, the FDEP and SWFWMD qualitatively monitor the coverage of hydrilla on an as-needed basis for the purposes of defining herbicide application needs. The methods used are not statistically valid, and therefore the results are not suitable for accurately quantifying trends or relating trends to other ecological conditions (e.g., water quality). Given the potential and observed impact of hydrilla and its treatment on lake water quality and fisheries, there is a need to quantify trends in the areal coverage and spatial distribution of this aggressive species at least every two years.

Target 3: Maintain the areal coverage of emergent aquatic vegetation (EAV) at 120 acres or more.

Objective 3: Estimate the status and trends in areal coverage, spatial distribution, and species composition of desirable, endemic emergent aquatic vegetation every two years.

Rationale: Currently no quantitative monitoring of emergent aquatic vegetation is being performed in Lake Tarpon on a regular basis. Given the importance of emergent aquatic vegetation as fish and wildlife habitat, as well as the potential for rapid changes in areal coverage, there is a need to assess the status and trends in areal coverage, species composition and spatial distribution of EAV at least every two years.

Target 4: Limit the areal coverage of cattail to 60 acres or less (<50% of the total EAV areal coverage target).

Objective 4: Estimate the status and trends in areal coverage and spatial distribution of cattail every two years.

Rationale: The dominance of cattail negatively impacts local fish and wildlife utilization, impedes human recreational usage, and detracts from visual aesthetics. Other than special diagnostic/feasibility studies, no quantitative monitoring of emergent aquatic vegetation in Lake Tarpon is conducted on a regular basis. Areal coverage and spatial distribution of cattail should be monitored every two years so that deviations from the target coverage will be recognized, and appropriate management actions implemented. Combined with Target 3 above, this target implicitly states that cattail should be managed so as to account for no more than 60 acres (or about 50%) of the minimal EAV areal coverage target of 120 acres.

The goals, targets and monitoring objectives related to the Aquatic Vegetation management issue are summarized in Table 5-2 below.

Table 5-2. Goals, targets and monitoring objectives for the Aquatic Vegetation issue.

Goal(s)

Target(s)

Monitoring Objective(s)

Vegetation shall be managed to maintain nuisance aquatic plants to the lowest feasible level while encouraging beneficial native plants to establish.

1. Maintain the areal coverage of desirable, endemic submerged aquatic vegetation (SAV) at 600 acres or more (>24% of the lake bottom area).

1. Estimate the status and trends in areal coverage, spatial distribution, and species composition of desirable, endemic submerged aquatic vegetation every two years.

 

 

2. Limit the areal coverage of hydrilla to 100 acres or less (<4% of the lake bottom area; <17% of the SAV areal coverage target).

2. Estimate the status and trends in areal coverage and spatial distribution of hydrilla every two years.

The lake and watershed should be managed to restore and enhance habitat abundance and diversity.

3. Maintain the areal coverage of emergent aquatic vegetation (EAV) at 120 acres or more.

3. Estimate the status and trends in areal coverage, spatial distribution, and species composition of desirable, endemic emergent aquatic vegetation every two years.

 

 

4. Limit the areal coverage of cattail to 60 acres or less (<50% of the total EAV areal coverage target).

4. Estimate the status and trends in areal coverage and spatial distribution of cattail every two years.

 

5.2.3 Fisheries

Under the targets developed for the Fisheries issue five specific monitoring objectives are proposed. The rationale for each proposed monitoring objective is discussed below.

Target 1: Maintain a fish community balance of F/C=3.0-6.0 (e.g., the ratio of forage fish biomass to carnivorous fish biomass).

Objective 1: Estimate the F/C ratio and the Fishery Quality Index (FQI) in Lake Tarpon every two years.

Rationale: The F/C ratio and the FQI are measures of fish community balance which can also serve as an indicator of lake trophic state. The F/C ratio and the FQI are calculated through quantitative sampling techniques typically using a stratified random design with block net and rotenone fish collection. The FGFWFC has conducted population studies for estimating the F/C ratio and FQI in Lake Tarpon on an irregular basis, approximately every five years. It is recommended that this quantitative sampling program continue on a regular basis, every two years at a minimum, so as to be coordinated with the sequencing of other monitoring programs.

Target 2: Maintain indices of Relative Stock Density (RSD) for major sport fish species of: 20-40% >14 inches for largemouth bass, 40-60% >6 inches for bluegill; 40-60% >7 inches for redear sunfish; and 40-60% >9 inches for black crappie.

Objective 2: Estimate the indices of Relative Stock Density (RSD) for major sport fish species in Lake Tarpon every two years.

Rationale: The Relative Stock Density index provides a numerical expression of population size structure, and is another quantitative measure of the population balance of major sport fish species. RSDs are determined through quantitative sampling techniques typically using a stratified random design with block net and rotenone fish collection. The FGFWFC has conducted population studies for estimating RSDs in Lake Tarpon on an irregular basis, approximately every five years. It is recommended that this quantitative sampling program continue on a regular basis, every two years at a minimum, so as to be coordinated with Objective 1 above as well as the sequencing of other monitoring programs.

Target 3: Maintain a voluntary angler catch and release rate for largemouth bass of 85% or greater.

Objective 3: Estimate the voluntary angler catch and release rate for largemouth bass in Lake Tarpon every two years.

Rationale: Voluntary angler catch and release of sport fish - primarily largemouth bass - promotes desirable F/C ratios and maintains a healthy sport fishery. Voluntary angler catch and release rates can be assessed relatively easily through various types of creel survey techniques. Given the rapidity by which lake water quality and the fish community structure can change, it is recommended that voluntary angler catch and release rates be assessed as a component of a comprehensive recreational fishery assessment to be performed every two years in combination with the quantitative sampling programs recommended for Objectives 1 and 2 above.

Target 4: Maintain fishing effort in Lake Tarpon at >150 hours of fishing per acre per year.

Objective 4: Estimate fishing effort in Lake Tarpon every two years.

Rationale: Fishing effort, or the number of hours fished per acre per year, can be assessed through various types of creel and recreational survey techniques. The measure of fishing effort forms the basis for calculating angler success rates. In combination with Objective 3 above, it is recommended that fishing effort be assessed as a component of a comprehensive recreational fishery assessment to be performed every two years.

Target 5: Maintain angler success rates of: >0.30 fish/hour for largemouth bass; and >3.0 fish/hour for panfish (bluegill, redear sunfish, crappie, and catfish).

Objective 5: Estimate the angler success rates for largemouth bass and panfish in Lake Tarpon every two years.

Rationale: Angler success rates are a function of both fish population structure and fishing pressure; and they are a direct measure of the recreational value of the sport fishery. Angler success rates, or catch per unit effort, can be assessed relatively easily through creel surveys. In combination with Objective 3 and 4 above, it is recommended that angler success rates be assessed as a component of a comprehensive recreational fishery assessment to be performed every two years.

The goals, targets and monitoring objectives related to the Fisheries management issue are summarized in Table 5-3 below.

Table 5-3. Goals, targets and monitoring objectives for the Fisheries issue.

Goal(s)

Target(s)

Monitoring Objective(s)

The fish populations of the lake should be managed to provide for sustained quality fishing opportunities.

1. Maintain a fish community balance of F/C=3.0-6.0 (e.g., the ratio of forage fish biomass to carnivorous fish biomass).

1. Estimate the F/C ratio and the Fishery Quality Index (FQI) in Lake Tarpon every two years.

 

 

2. Maintain indices of Relative Stock Density (RSD) for major sport fish species of: 20-40% >14 inches for largemouth bass, 40-60% >6 inches for bluegill; 40-60% >7 inches for redear sunfish; and 40-60% >9 inches for black crappie.

2. Estimate the indices of Relative Stock Density (RSD) for major sport fish species in Lake Tarpon every two years.

 

 

3. Maintain a voluntary angler catch and release rate for largemouth bass of 85% or greater.

3. Estimate the voluntary angler catch and release rate for largemouth bass in Lake Tarpon every two years.

 

 

4. Maintain fishing effort in Lake Tarpon at >150 hours of fishing per acre per year.

4. Estimate fishing effort in Lake Tarpon every two years.

 

 

5. Maintain angler success rates of: >0.30 fish/hour for largemouth bass; and >3.0 fish/hour for panfish (bluegill, redear sunfish, crappie, and catfish).

5. Estimate the angler success rates for largemouth bass and panfish in Lake Tarpon every two years.

5.2.4 Wildlife and Associated Habitat

Under the targets developed for the Wildlife and Associated Habitat issue six specific monitoring objectives are proposed. The rationale for each proposed monitoring objective is discussed below.

 

Target 1: Maintain or increase the number of eagle territories in the Lake Tarpon drainage basin.

Objective 1: Annually determine the number of nesting eagle pairs in the Lake Tarpon drainage basin.

Rationale: Nesting eagle pairs have been documented in the Lake Tarpon basin for many years. A decline in eagle territories may indicate that adjacent or proximate land uses are interfering with eagle nesting activity, or that an associated ecological stress, exhibited by a decline in the health of the lake or abundance of the fish population, has occurred. The occurrence of nesting eagles should be determined in coordination with the FGFWFC annual eagle census program.

 

Target 2: Maintain or increase the species richness of endemic bird populations in the Lake Tarpon drainage basin.

Objective 2: Annually estimate the species richness and abundance of endemic bird populations in the Lake Tarpon drainage basin.

Rationale: Endemic birds possess habitat and life cycle requirements corresponding to the historic ecological succession of Lake Tarpon. A decline in the presence or abundance of native species may indicate ecological or human-induced stress. The presence and abundance of exotic birds results in interference with natural ecological processes such as competition and predation and increased nest parasitism. It is recommended that bird species richness in the basin be estimated annually from summer and winter bird counts through coordination with the local Audubon Society Chapter, the FGFWFC, and the Brooker Creek Preserve.

Target 3: Maintain the existing acreage (780 acres) of viable gopher tortoise habitat (e.g., xeric uplands) in the Lake Tarpon drainage basin.

Objective 3: Estimate the acreage of viable gopher tortoise habitat in the Lake Tarpon drainage basin every two years.

Rationale: Currently, the acreage of viable gopher tortoise habitat in the Lake Tarpon drainage basin is estimated at approximately 800 acres, however, advancing development of remaining uplands is rapidly reducing this acreage. Given the development pressures on remaining upland parcels, public purchase or establishment of public easements on parcels of suitable gopher tortoise habitat would be the most effective method of ensuring available habitat for gopher tortoises and their commensals. It is recommended that gains and losses in upland habitat be quantified every two years. In addition, this effort should be coordinated with the FGFWFC habitat mapping program.

Target 4: Maintain the existing acreage (1,360 acres) of viable wetland habitat in the Lake Tarpon drainage basin.

Objective 4: Estimate the acreage of viable wetland habitat in the Lake Tarpon drainage basin every two years.

Rationale: Although there have been efforts at the state level to track wetland trends via permit records, no state or local system currently exists for tracking wetland gains (e.g., mitigation, restoration) and losses (e.g., dredge and fill) at the resolution of the Lake Tarpon drainage basin. It is recommended that wetland gains and losses be quantified every two years in conjunction with the aquatic vegetation surveys discussed above.

Target 5: Increase the number of participants in the Lake Tarpon Habitat Improvement Program by 10 parcels per year.

Objective 5: Annually determine the number of participants in the Lake Tarpon Habitat Improvement Program.

Rationale: Successful urban wildlife management in the Lake Tarpon basin will be largely achieved on a parcel by parcel basis. A simple annual accounting of the number of residential and/or commercial property owners committing to the program per year is recommended.

Target 6: Increase the number of wildlife underpasses in the Lake Tarpon drainage basin.

Objective 6: Annually determine the number of wildlife underpasses constructed.

Rationale: As roadways in the drainage basin require improvement, the construction or retrofitting of strategically located wildlife underpasses should significantly improve the mobility, expansion and genetic variability of wildlife populations by providing linkages for wildlife dispersion. Additionally, wildlife mortality due to vehicular collision would decrease with an alternative to crossing an unprotected and busy highway. A simple annual accounting of the number of constructed wildlife underpasses is recommended.

The goals, targets and monitoring objectives related to the Wildlife and Associated Habitat management issue are summarized in Table 5-4 below.

Table 5-4. Goals, targets and monitoring objectives for the Wildlife and Associated Habitat issue.

Goal(s)

Target(s)

Monitoring Objective(s)

The lake and watershed should be managed to restore and enhance habitat abundance and diversity.

1. Maintain or increase the number of eagle territories in the Lake Tarpon drainage basin.

1. Annually determine the number of nesting eagle pairs in the Lake Tarpon drainage basin.

 

 

2. Maintain or increase the species richness and abundance of endemic bird populations in the Lake Tarpon drainage basin.

2. Annually estimate the species richness and abundance of endemic bird populations in the Lake Tarpon drainage basin.

The lake and watershed should be managed to restore and maintain populations of endemic wildlife species.

3. Maintain the existing acreage (780 acres) of viable gopher tortoise habitat (e.g., xeric uplands) in the Lake Tarpon drainage basin.

 

3. Estimate the acreage of viable gopher tortoise habitat in the Lake Tarpon drainage basin every two years.

 

 

4. Maintain the existing acreage (1,360 acres) of viable wetland habitat in the Lake Tarpon drainage basin.

4. Estimate the acreage of viable wetland habitat in the Lake Tarpon drainage basin every two years.

 

 

5. Increase the number of participants in the Lake Tarpon Habitat Improvement Program by 10 parcels per year.

5. Annually determine the number of participants in the Lake Tarpon Habitat Improvement Program.

 

 

6. Increase the number of wildlife underpasses in the Lake Tarpon drainage basin.

 

6. Annually determine the number of wildlife underpasses constructed.

 

5.2.5 Flood Control

Under the targets developed for the Flood Control issue two specific monitoring objectives are proposed. The rationale for each proposed monitoring objective is discussed below.

Target 1: Prevent flood damage ($0) to all properties within the Lake Tarpon drainage basin.

Objective 1: Annually assess flood damage (dollars) to all properties within the Lake Tarpon drainage basin.

 

Rationale: The aggregate sum of property damage (in dollars) from flooding in the Lake Tarpon drainage basin should be assessed and reported annually to monitor the possible impacts of other lake management actions (e.g., water level fluctuations) on flood protection.

Target 2. Manage lake levels to improve water quality and aquatic vegetation conditions while maintaining maximum flood protection.

Objective 2: Estimate monthly compliance with the prescribed Lake Tarpon water level fluctuation schedule.

Rationale: Strict compliance with the prescribed water level fluctuation schedule will allow lake managers to assess the effectiveness of altering water levels as a means of improving water quality and aquatic vegetation conditions. Average daily water level records from the Lake Tarpon outfall control structure are needed to assess monthly compliance with the prescribed schedule.

The goals, targets and monitoring objectives related to the Flood Control management issue are summarized in Table 5-5 below.

Table 5-5. Goals, targets and monitoring objectives for the Flood Control issue.

Goal(s)

Target(s)

Monitoring Objective(s)

The lake and watershed should be managed to minimize flood damage.

1. Prevent flood damage ($0) to all properties within the Lake Tarpon drainage basin.

1. Annually assess flood damage (dollars) to all properties within the Lake Tarpon drainage basin.

 

 

2. Manage lake levels to improve water quality and aquatic vegetation conditions while maintaining maximum flood protection.

2. Estimate monthly compliance with the prescribed Lake Tarpon water level fluctuation schedule.

 

 

5.2.6 Recreation and Aesthetics

Under the targets developed for the Recreation and Aesthetics issue four specific monitoring objectives are proposed. The rationale for each proposed monitoring objective is discussed below.

Target 1: Prevent boating and personal water craft accidents (0 accidents).

Objective 1: Annually determine the number of boating and personal water craft accidents occurring on Lake Tarpon.

Rationale: The total annual number of boating accidents reported on Lake Tarpon is a reasonably good measure of public safety and enforcement effectiveness.

Target 2: Maintain Class-III water quality standards for total and fecal coliform bacteria.

Objective 2: Estimate for Lake Tarpon and the outfall canal: 1) the monthly trends in coliform bacteria; and 2) the frequency, duration, and magnitude that monthly total and fecal coliform concentrations exceed 2,400/100 ml and 800/100 ml, respectively.

Rationale: Previous water quality surveys have indicated that coliform concentrations in Lake Tarpon periodically exceed State water quality standards, however, routine measurements are currently not being performed. The monthly measurement of coliform bacteria concentrations in Lake Tarpon should be performed to ensure continued public health and safety with respect to water contact recreation. It should be noted that some uncertainty currently exists within the regulatory community as to the validity of coliform testing as an indicator of contamination. Statewide investigations are in progress to develop more meaningful water quality standards with regard to the public health risks of water contact recreation. Consideration should be given to delaying the implementation of coliform monitoring until the findings of these investigations are published.

Target 3: Attain 90% positive responses on recreational user and lakefront resident opinion surveys.

Objective 3: Assess recreational user and lakefront resident satisfaction every four years.

Rationale: Pinellas County and the FGFWFC have periodically conducted recreational user surveys, and Pinellas County has recently completed a lakefront resident survey. The survey format should be refined and implemented every four years to assess trends in public opinion.

Target 4: Maintain or increase recreational usage of the lake while still maintaining 90% user satisfaction.

Objective 4: Annually estimate the number of recreational users visiting the lake.

 

Rationale: Both Chesnut and Anderson Parks keep daily records of user trips, and the use generated from these two parks probably represents over 80% of the total user population at any given time. Park user data, and other available recreational user data (e.g., ski clubs, fishing guides, etc.) should be summed annually to estimate the total number of recreational users annually visiting the lake. This objective must also incorporate the user satisfaction data collected under Objective 3 above.

The goals, targets and monitoring objectives related to the Recreation and Aesthetics management issue are summarized in Table 5-6 below.

 

Table 5-6. Goals, targets and monitoring objectives for the Recreation and Aesthetics issue.

Goal(s)

Target(s)

Monitoring Objective(s)

The lake should be managed in such a manner as to provide for safe and enjoyable recreational boating activities.

1. Prevent boating and personal water craft accidents (0 accidents).

1. Annually determine the number of boating and personal water craft accidents occurring on Lake Tarpon.

The lake should be managed to provide opportunity for safe skiing and swimming.

2. Maintain Class-III water quality standards for total and fecal coliform bacteria.

2. Estimate for Lake Tarpon and the outfall canal: 1) the monthly trends in coliform bacteria; and 2) the frequency, duration, and magnitude that monthly total and fecal coliform concentrations exceed 2,400/100 ml and 800/100 ml, respectively.

Recreational use of the lake should be managed such that the needs of multiple user groups are balanced and optimized.

3. Attain 90% positive responses on recreational user and lakefront resident opinion surveys.

 

3. Assess recreational user and lakefront resident satisfaction every four years.

The lake should be managed such that other desirable aesthetic qualities are protected and/or enhanced.

4. Maintain or increase recreational usage of the lake while still maintaining 90% user satisfaction.

 

4. Annually estimate the number of recreational users visiting the lake.

 

 

5.2.7 Public Education

Under the targets developed for the Public Education issue two specific monitoring objectives are proposed. The rationale for each proposed monitoring objective is discussed below.

Target 1. Annually provide for a minimum of four (4) public education/media events.

Objective 1: Annually determine the number of public education/media events conducted.

Rationale: A simple accounting of the number public education/media events should be recorded annually to track attainment with the target.

Target 2. Attain 90% positive responses on recreational user and lakefront resident public opinion and knowledge surveys.

Objective 2: Assess recreational user and lakefront resident public knowledge of the lake management plan every four years.

Rationale: It is recommended that the public education survey be combined with the recreational user and lakefront resident satisfaction surveys discussed above. Due to the demand on staff resources, surveys conducted at a frequency greater than every four years are not recommended.

The goals, targets and monitoring objectives related to the Public Education management issue are summarized in Table 5-7 below.

Table 5-7. Goals, targets and monitoring objectives for the Public Education issue.

Goal(s)

Target(s)

Monitoring Objective(s)

Education in matters related to and affecting the other goals of the Lake Tarpon Management Plan shall be provided.

1. Annually provide for a minimum of four (4) public education/media events.

1. Annually determine the number of public education/media events conducted.

 

 

2. Attain 90% positive responses on recreational user and lakefront resident public opinion and knowledge surveys.

2. Assess recreational user and lakefront resident public knowledge of the lake management plan every four years.

5.3 SUMMARY OF THE RECOMMENDED MONITORING PROGRAMS

The existing monitoring programs currently being implemented by the various responsible agencies only partially address the data needs of the comprehensive Lake Tarpon Drainage Basin Management Plan. Many data gaps exist which must be addressed through the modification of existing monitoring programs, as well as the implementation of new monitoring programs. In addition, the existing monitoring programs in most cases lack clearly articulated monitoring objectives which are logically linked to management goals and level-of-service targets. This lack of focus has resulted in a less than cost-effective expenditure of available funding resources for monitoring activities.

A total of 13 monitoring program elements have been identified to fill data needs with respect to the implementation of the Lake Tarpon Drainage Basin Management Plan. Table 5-8 below summarizes the monitoring objectives addressed, the sampling frequency, and the recommended agency responsibility(s) for each monitoring element. Key differences between the existing monitoring activities and the proposed comprehensive Lake Tarpon Monitoring Program are summarized below:

- Cost-sharing for laboratory analyses between Pinellas County and SWFWMD was anticipated in the Lake Tarpon SWIM Plan, and SWFWMD currently provides laboratory analyses associated with the nonpoint source/tributary and groundwater loading monitoring programs. For consistency with historic data, it is recommended that Pinellas County continue to provide laboratory analyses for all in-lake samples.

- Because of their extensive in-house expertise in groundwater monitoring, as well as their specific diagnostic work on the Lake Tarpon groundwater system, it is recommended that SWFWMD be responsible for the installation and maintenance of, and collection of samples from, the proposed groundwater seepage meters.

- Because of their extensive in-house expertise and experience in fishery biology, as well as their history in monitoring trends in the Lake Tarpon sport fishery, it is recommended that the FGFWFC continue to be responsible for the quantitative assessment of fish populations. It is, however, also recommended that the collection of angler use data be delegated to PCDEM and incorporated into a comprehensive recreational use and lakefront resident survey program to be conducted every four years.

- Calculated water and nutrient budget for the previous calendar year; and ,

- An assessment of compliance with each of the established level-of-service targets.

The detailed sampling protocols for each of the recommended monitoring elements are provided in the Task 3.2.11 Interim Report. It should be noted that since the publication of the Task 3.2.11 Interim Report, PCDEM has implemented several components of the recommended monitoring programs. For example, beginning in January 1997, PCDEM initiated sampling programs to assess pollutant loadings from: 1) nonpoint sources and tributaries; 2) groundwater; and 3) atmospheric deposition. Furthermore, an additional in-lake sampling station was added at the outfall structure to measure the nutrient mass discharged from lake. Full implementation of all recommended monitoring programs are recommended to meet the requirements of the Plan.

Table 5-8. Summary of recommended monitoring program elements.

Monitoring Element

Objectives Addressed

Sampling Frequency

Responsible Entities

In-Lake Water Quality

Water Quality: 1, 2A, 2B, 4, 5B, 5C, and 5D

Recreation and Aesthetics: 2

Monthly

PCDEM - field sampling and laboratory analysis

Tributary and Nonpoint Source Loadings

Water Quality: 3A

Monthly

PCDEM - field sampling

SWFWMD - laboratory analysis

Groundwater Loadings

Water Quality: 3B

Semi-annual (wet and dry season)

SWFWMD - field sampling and laboratory analysis

Atmospheric Deposition Loadings

Water Quality: 3C

Daily

PCDEM - field sampling and laboratory analysis

Dissolved Oxygen Minima

Water Quality: 5A

1-3 days/month during index period of July-September

PCDEM - field sampling and laboratory analysis

MSSW Inventory

Water Quality: 6

Ongoing

PCDEM with logistical support from SWFWMD.

Submerged Aquatic Vegetation

Aquatic Vegetation: 1 and 2

Every 2 years

PCDEM with logistical support from SWFWMD and FDEP

Emergent Aquatic Vegetation

Aquatic Vegetation: 3 and 4

Every 2 years

PCDEM with logistical support from SWFWMD and FDEP

Fish Populations

Fisheries: 1

Every 2 years

FGFWFC with logistical support from PCDEM

Bird Populations

Wildlife and Associated Habitat:

1 and 2

Semi-annual (summer and winter)

PCDEM - coordination only - with logistical support by Audubon Society and FGFWFC

Upland and Wetland Habitat

Wildlife and Associated Habitat:

3 and 4

Every 2 years

PCDEM in coordination with FGFWFC

Recreational User and Lakefront Resident Survey

Fisheries: 2 and 3

Recreation and Aesthetics: 3

Public Education: 2

Every 4 years

PCDEM with logistical support from FGFWFC for angler use data

Miscellaneous Accounting

Wildlife and Associated Habitat:

5 and 6

Recreation and Aesthetics:

1 and 4

Flood Control: 1 and 2

Public Education: 1

Annual

PCDEM