biological monitoring report - pelican bay...

CLAM BA Y RESTORATION AND MANAGEMENT

BIOLOGICAL MONITORING REPORT

TURRELL & ASSOCIATES, INC. -SIXTH ANNUAL REPORTLEWIS ENVIRONMENTAL SERVICES, INC. - REPORT NUMBER 9

IN FULFILLMENT OF DEP PERMIT # 0 128463-001-JCUNITED STATES ARMY CORPS OF ENGINEERS PERMIT # 199602789 (IP-CC)

FOR: THE PELICAN BAY SERVICES DIVISION

DECEMBER 2005

TURRELL & ASSOCIATES, INC.: Todd T. Turrell, P.E., Tim Hall, Kara Cave

3584 Exchange Ave, Suite BNaples, FL 34104Tel: (239) 643-0166Fax: (239) 643-6632E-mail: [email protected]

Baseline report, #1: pre-dredging spring 1999Time zero report, #2: post-dredging summer 1999First Annual report, #3: one year post-dredging fall 2000Second Annual report, #4: two years post-dredging fall 2001Third Annual report, #5: three years post-dredging fall 2002Fourth Annual report, #6: four years post-dredging fall 2003Fifth Annual report, #7: five years post-dredging fall 2004Sixth Annual report, #8: six years post-dredging fall 2005

LEWIS ENVIRONMENTAL SERVICES, INC.: Roy R. "Robin" Lewis, III,Michael J. Marshall, Ph.D.

P.O. Box 220005Tampa, FL 33622-0005Tel: (888) 889-9684Fax: (813) 649-1425E-mail: [email protected] / [email protected]

Baseline and time zero reports, #1: pre and post flushing channel construction in the die-offarea, 1997First Annual report, #2: one year after flushing channel construction, 1997Second Annual report, #3: two years after flushing channel construction, 1998Third Annual report, #4: following additional flushing channel construction in 1999 and 2000,2000Fourth Annual report, #5: following additional flushing channel construction in 2001, 2001Fifth Annual report, #6: one year after flushing channel cuts in 2001, 2002Sixth Annual report, #7: two years after flushing channel cuts in 2001, 2003Seventh Annual report, #8: three years after flushing channel cuts in 2001, 2004Eighth Annual report, #9: four years after flushing channel cuts in 2001, 2005

CONTENTS and FIGURES (given in italics)

Turrell & Associates, Inc. Sixth Annual ReportLewis Environmental Services Report #9

1.0 Introduction to the Sixth Annual Report1.1 2004 work completed 1-2

2.0 Mangroves2.1 Turrell & Associates monitoring 3-4

Infra-Red Aerial 5Mangrove die-off and stress acreages 6

Plot locations ) 7Plots 1-11: graphs and descriptions 8-18

2.2 Lewis Environmental Services monitoring 19Plot locations 20Discussion 21-22

Rainfall chart 23Batis cover chart 24Plot photographs 25-30

3.0 Seagrasses3.1 Methodology 31

3.2 Data 31

Transects 1-4, summaries 31-32

Transect map 33

Graphs and descriptions for transects 5-9 34-38

4.0 System Overview4.1 Aerial Photography 394.2 Hurricane Wilma 434.3 Mangroves 44-47

4.4 North tram replanting area 48

5.0 Bathymetric Monitoring 49-51

6.0 Water Quality Summary6.1 Sampling results 526.2 Conclusions 54

8.0 Conclusions 55

8.1 Mangroves 55-56

8.2 Seagrasses 56-57

9.0 2006 Focus 58-59

Clam Bay Restoration and ManagementBiological MonitoringTurrell & Associates, Inc.: Sixth Annual ReportLewis Environmental Services, Inc.: Report #9November 2005

1.0 INTRODUCTION TO THE SIXTH ANNUAL REPORT

The Florida Department of Environmental Protection permit #0128463-001-JC andUnited States Army Corps of Engineers permit #199602789 (IP-CC), authorizingrestoration activities in the Clam Bay system make annual monitoring through fixedvegetative survey of the Clam Bay system a special condition of the permit for tenconsecutive years. This report presents Year 6 of the schedule with the final due in 2008.

The annual monitoring conducted within the system consists of three distinctcomponents. The first is hydrographic monitoring and analysis of bathymetric and tidegauge data. This is conducted to monitor the status of Clam Pass and analyze theeffectiveness of the pass to keep itself open. The second component is water qualitymonitoring. Monthly monitoring of water quality parameters is conducted and analyzedfor trends in improving or deteriorating water quality within the Clam Bay system. Thethird component of the annual monitoring is the biological component. Monitoring ofvegetative plots is undertaken to measure and analyze recovery of the mangrove die-offareas. The analysis of this third component comprises the bulk of this report thoughsummaries of the other two are also presented. More detailed reports on the water qualityand hydrographic monitoring are produced by the sub-consultants responsible for thoseelements, however for brevity's sake are not included in full as part of this report but areinstead included as attachments.

The biological work presented consists of eleven mangrove monitoring plots and nineseagrass transects set up by Turrell & Associates Inc., in addition to the eleven plots inthe original die-off area surveyed by Lewis Environmental Services, Inc. Backgroundand methodologies of the monitoring are provided in following sections.

In section 8.0 the focus of work and recommendations of specific tasks for the comingyear are described. The scope of work has been developed based on the results ofmonitoring surveys and through collaboration with the consultant team and staff of thePelican Bay Services Division. One component of this future work is the continuedmonitoring and restoration work associated with the cattail removal efforts along theberm. Most of the major work items recommended in previous years have beencompleted so that most future work efforts will be related to the monitoring andmaintenance of all of the flushing channels established throughout the system.

1.1 2005 WORK COMPLETED

A focus for additional work to be carried out in 2005 was presented in the concludingsections of the Fifth Annual monitoring report. This included the following items thathave been successfully completed:

Clam Bay Restoration and Management

2Biological MonitoringTurrell & Associates, Inc.: Sixth Annual ReportLewis Environmental Services, Inc.: Report #9November 2005

All planned flushing channels for the system have been completed. Future channelswill be constructed on an as-needed basis.Continued clearing of any fallen trees within the main waterways of Clam Bay.Continued exotic and nuisance vegetation removal.Continued monitoring of the cattail and restoration areas along the berm.Ongoing monitoring and maintenance of the existing flushing channels.Continued year-round monitoring of the system.

It was our initial intent to continue water level monitoring through the use of our water levelloggers. However, persistent technical and storm-related problems created difficulties inreceiving accurate data. We are currently exploring other options for monitoring water levelswithin the mangroves.

The overview for 2005 is that all efforts undertaken thus far still appear to have been successful.This is a highly complex estuarine ecosystem and continued diligence is needed to monitor theongoing recovery of the mangroves within the die-off areas. Unforeseen events such as thehurricanes of the past couple of years add a measure of uncertainty to the monitoring efforts andhighlight that continued diligence is needed to insure the waterways and channels remain clear.Blocked channels can have detrimental effects as seen in a new die-off area that was caused byHurricane Charlie last year.



2.0 MANGROVES

2.1

Turrell & Associates Inc, Sixth Annual Mangrove Data: Graphs, Picturesand Plot Descriptions

Methodology

To effectively monitor mangrove health and changing conditions over the life ofthe permit, fixed plots were established throughout the system. Approximate plotlocation was determined from examination of low elevation aerial photographsand finalized upon ground truthing. Initially, 10 plots were established andmonitored. In 2002, an additional plot was added in a new lightning strike zone.Locations are illustrated on the attached map (Figure 2). Primary considerationsin plot placement were as follows:

To provide a spread of plots throughout the system,To supplement, without duplicating, the work of other researchers,To monitor areas of special concern such as small additional die-off orstressed areas,To fulfill permit requirements.

The previous monitoring work of Lewis Environmental Services entailed eleven10m x 10m permanent quadrats within the main die-off area, in the north-westportion of the system. Turrell and Associates has established an additional 11plots and has the option of establishing additional plots should the need arise. TheConservancy of Southwest Florida was carrying out an additional research effortto monitor mangrove re-growth in Clam Bay following the restoration work. TheConservancy, the Mangrove Action Group, and the Pelican Bay Foundation haveall provided funding for the Conservancy's work. No data analysis for theConservancy's monitoring is included in this report. The current study plotplacement throughout the 500-acre system is considered sufficient for this portionof the study. As mentioned, additional plots may be established at a later date ifconditions (further die-offs or stressed areas) suggest the necessity.

Each Turrell & Associates monitoring plot is a measured 10 m x 10 m square,staked at each corner and marked in the center point with labeled PVC piping.Monitoring activities included enumeration and mapping of living and dead treeswith diameters at breast height (DBH) recorded for all living trees with a DBHgreater than 2.5 cm. Seedlings were identified by species and numbers wereestimated by count or percent cover. In 2003, each measured tree was tagged andmarked with a number to allow for easier tracking of individual trees as well as toallow more specific comparisons over time. Any saplings that grow to sufficient



size (>2.5 cm DBH) between monitoring events are added to our tree counts andreceive tags and numbers as well.

Photographs were taken and any additional observations, including standingwater, wildlife or signs of stress noted. Time, tide, and prevailing weather wasnoted for each survey.

Additionally, meandering transects were walked throughout the system to inspectstressed areas or to observe areas of concern related by residents of thecommunity or through examination of aerial photographs. These surveys areconducted throughout the year as needed. Observations made during thesepedestrian transects are noted in the general biological discussion of this report.

Results

See attached sheets. Plot discussions have been included on the same page.

This year again presented challenges to the ongoing health of the mangrovesystem in the form of high winds and surge associated with Hurricane Wilma. Ourongoing monitoring showed that the flushing cuts installed so far still seem to befunctioning as expected. Although there is obvious stress in the form of leaf lossand downed trees in many portions of the system, overall growth and recovery isnot expected to be impacted by the storm.

0 1 /8 1 /461

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DESIGNED. T T T REVISION TAB NAME 2035 IRPEELICANJ BAY DRAWN BY' KD N/A SHEETCREATED 11-01-05 N/A SCALE /' 1/4 MILE

2005 INFRARED AERIAL JOB NO . 9645 N/A

SECTION-TOWNSHIP- RANGE-

DATE OF AERIAL: 2005

Turrell & Associates, Inc.Marine & Environmental Consulting

Cr 3584 Exchange Ave. Suite B. Naples, FL 34104-3732Email: [email protected] Phone: (239) 643-0166 Fax: (239)643-6632

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Turrell & Associates, Inc.Marine & Environmental Consulting

3584 Exchange Ave. Suite B. Naples, FL 34104-3732Email: [email protected] Phone: (239) 643-0166 Fax: (239) 643-6632

MI 2005 DIEOFF (3.14 ACRES)

STRESSED AREAS (4.53 ACRES)

COMMON DIEOFF AREAS (21.58 ACRES)

RECOVERY AREAS (26.52 ACRES)

GULF OF MEXICO

CLAM BAY OPEN WATERSTurrell & Asnociates. Inc.

)<1112°P Marina k Envtroomestal Coosa/Wig3564 1. .11.. butte B, Naples, PI. NWPhone: (04I) 643-01641 per 648-0632

WETLAND VEGETATION 11-111111: tttuse84B611soLooal

CLAM BAY• •

(MANGROVES)• FIGURE 2TURRELL & ASSOCIATES MONITORING PLOTS TRANSECT & PLOT LOCATIONS

2 LEWIS ENVIRONMENTAL MONITORING PLOTS X2:8C3 KV11231 PA. IlMe

MAW TOI MEETMIT 31-14-1111 VALEJOS Ma

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2005

PLOT 1

Growth has been noted in the measured trees fromlast year. Canopy cover is still pretty evenly splitbetween whites and reds. The trees are in slightlybetter condition than last year, though some leafdamage can be seen in the leaves of these treesand around the plot. The groundcover is still mostlyred mangrove seedlings with a few whites,concentrated in the northern half.

2005

PLOT 2

This plot is still dominated by reds in the measurableclass sizes, and more reds have appeared in thegroundcover, which was previously dominated by whites.Some increase in height of seedlings overall is noted.Overall condition of the trees appears to have declined,but this seems to be primarily from leaf loss from thehurricane.

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2004 2005

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PLOT 3

Red mangroves dominate this plot, with only a few blacks andwhites present. Red mangrove seedlings have caught up withthe whites, which is now about 50/50 in groundcovercomposition between the two. Canopy cover is concentratedin the south half - overall about 50%, red dominated. Overallcondition of the trees is rather good considering the hurricanestress. One white tree has been added due to its increasedsize. One previously broken white has died as expected fromlast year's notes due to hurricane Charley. One tree newlybroken at the top appears as if it may still live.

2004

2005

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2005

PLOT 4

This plot had very significant damage in and around the area.Two small red trees are unaccounted for, and two large redswere broken. Groundcover is difficult to accurately assess withall the debris, but still appears to be about 90% coverage byleather fern, with a large amount of vines that cover some of thesmaller trees (as noted previously). There is some saltbushpresent, and there is still some Brazilian pepper within the plot.One corner stake is missing, and a tree was flagged as close aspossible to the estimated original location.

2004

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Species

2004

PLOT 5

The area consists of a fair mix of red and black mangroves,although red seedlings/saplings dominate over black. Canopycover has maintained around 50-60%, composed of both maturereds and blacks. Groundcover maintains about the samecoverage as last year (20-30%) but the seedlings are increasingin height. Some of the mature trees have declined slightly intheir condition, including a few blacks that were dead stumpswith some new growth coming in. Those now appear to havelost the new growth. Most trees are at least in fair condition,however, and the hurricane may have caused the conditiondecline noted — which should be temporary. There were manytrees down that have fallen in from around the plot.

2005

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PLOT 625

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Black mangroves provide the only canopy in this plot. This plotseems to have been hit harder by leaf stripping from the storm,as many of them had no leaves or are in poor condition. Twoblack mangroves appear to have died since last year.However, more white mangrove saplings have grown fromgroundcover classification to midstory, and have been added toour chart. Red mangroves now cover about 50% of the ground,along with some whites, though no Batis is noted this year.

Species

2004 2005

90

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PLOT 7This plot continues to progress very well overall. The areais still heavily white mangrove dominated, though a fewmore blacks are noted in the groundcover. This plot wasalso hit hard by hurricane-related leaf loss, so all arecategorized as being in fair to poor condition. It is notexpected that the trees here should recover from thestorm. They have increased in size overall from last year.However, there are some trees that are down or haveother trees resting on them which may affect theirrecovery.

Last year the trees started to become too tall for the camera to show the leaves, but they were there. This year, you can seehow there is more light coming in from the storm-stripped canopy.

2004

2005

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Species

PLOT 8

White mangrove saplings still dominate this plot. Almost alltrees remain less than 2.5 cm DBH, but one red hasreached recordable size. There is still Batis present, thoughit was all brown at the time of the site visit making it seemto cover less area. Seedlings are still primarily whites withonly a few reds and blacks. There is still no canopy coverpresent at this time, but more saplings in the southeastcorner should reach recordable DBH next year.

2004

2005

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PLOT 9

Ground cover continues to be very thick with leather fern, whichoverpowers much of the plot. Canopy has decreasedsignificantly, both in and around the plot, as a result ofHurricane Wilma — from 30% down to 5%. This is the same plotthat seemed to take more damage from Cahrley last year aswell. One tree could not definitively be located due to theamount of damage in this location. One large red is broken andwill likely die. However, a few new trees were noted with > 2.5cm DBH that were added to our chart.

Species

2004

2005

2005

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Species

2004

PLOT 10Groundcover of Batis and mangrove seedlings hasremained relatively stable this year. One red that wasbroken lat year is still alive. Several trees were down in andaround the area. Another red that showed galls last year isnow broken and dead, and one other is broken and may die.Those that were not broken by the storm appear to be ingood condition. We have added two new white mangrovesto the plot due to their growth.

WHITE BLACK

SpeciesRED

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PLOT 11

There is a significant amount of storm damage to this plot.Five of our recorded trees are broken at the top. Severalothers are leaning or have other trees on top of them. On apositive note, however, many white seedlings have croppedup and appear to be doing well, covering about 85% of theplot. There are also a few black seedlings and some leatherfern. Previously the plot had relatively little groundcover,composed primarily of Batis. No Batis was noted this year,however, it was difficult to accurately determine groundcovercomposition with so much debris within the plot. Aside fromthe storm damage, growth of recorded trees has progressedwell.

2004 2005

Clam Ray Restoration and Management

19

Biological MonitoringTurrell & Associates, Inc.: Sixth Annual ReportLewis Environmental Services, Inc.: Report #9November 2005

2.2 Lewis Environmental Services, Inc.: Mangrove Data

Methodology and additional data for Lewis Environmental Services is attachedseparately in their report, and will not be repeated here for brevity's sake.Photographs and discussion from the LES report are included on the followingpages. Tree census results are graphically depicted in the attached report, alongwith actual numbers of mangrove shrubs per plot.

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Lewis Environmental Services Inc. provides the following discussion of their results:

Annual rainfall amounts from 1996 through October 2002 have been less than theexceptionally heavy rains of 1995 when many large and small trees died. This factoralone probably contributed greatly to the start of the recovery process seen during 1997and which apparently continues through 2002. In 2003 rainfall exceeded, by severalinches, most of the previous years yet the mangroves within the Strand impacted areacontinue to thrive. This success in survival throughout the wet season is undoubtedlydue to the construction and maintenance of the flushing cuts throughout this area.Rainfall in 2004, despite the hurricanes which passed the project area, was less (throughOctober) than the previous years.

Since the forest floor within the entire forest is virtually level the success in forestregeneration that we have seen near the Strand is due to the network of small flushingcuts that have been dug throughout most of this area. Each channel, due to the leveltopography, can only drain a small zone. It is within these narrow zones, on each sideof most channels, where mangroves have recruited successfully and which continue togrow. Two large areas, east of the main North South channel, where flushing cutnetworks have not yet been dug remain stressed with little sign of recovery. Flushingcuts will be dug in these areas within the next 2 or 3 years. The dense growth ofmangroves in and around Plots 1 and 3 contain a mixture of reds, black and whitemangroves. At present the white mangroves are most abundant but this seems to be apattern typical of natural recruitment of mangroves in similar areas throughout the ClamBay area. Casual observations on small areas that have been damaged by lighteningstrikes show that the first mangroves to recruit to the openings are usually whites.Eventually these are out competed and replaced by blacks and or reds.

During 1999 Batis maritima died out over much of the forest floor. By October2001 it recovered again across most of the forest floor and within the boundaries ofmost of the LES monitoring plots. Presumably the 1999 die-off was due to the largeamount of rainfall in this area as recorded at the Pelican Bay Golf Course duringSeptember 1999. Direct rainfall and heavy runoff from upland developed areas aroundClam Bay presumably combined to hold water levels above the tolerance levels ofBatis. LES staff has witnessed water flowing, from the sprinkler systems on thecondominium grounds, across the Strand road into the mangrove forests. The controlplots (9, 10, and 11), and Plot 8, due to shading from an intact mangrove canopy, werenever covered by Batis. After the flushing channels were dug in the main die-off area,to the east of the Strand, Batis quickly recovered. Due to the change to a once per yearmonitoring schedule we cannot accurately chronicle how quickly Batis responded to thechanges in hydrology brought about by the new channels. Batis continues, in 2005, toflourish in the plots that are not shaded by dense tree growth.



Prior to the construction of the flushing cuts LES staff established their locations bylooking for very wet low spots. These spots were marked with flagged stakes. This wasdone during the dry season when the die-off area was otherwise dried out. The wet spots(and very soft spots) presumably represented the lowest elevations within the forest.Most of the wet spots were devoid of any trace of plant growth. Following the walkingsurvey a network of small channels were marked and later dug by a crew fromFloraquatics, Inc. Some of these low spots were adjacent to the Riley experimentalplots. We attempted to avoid those areas. New flushing cuts were dug during thesummers of 2004 and 2005. Maintenance of these cuts is normally done before the wetseason begins and after storm events.

The rearrangement of the mangrove results into areas with and without flushingchannels was done to emphasize the impact and effectiveness of the flushing channels.Those plots adjacent to old channels (Plots 1,3,4 ,and 8) support the best growth ofmangroves, mangroves, in plots 2 and 6, adjacent to new channels dug in the summerof 2004 have not had time to respond to improved tidal flushing, and plots 5 and 7(notnear flushing channels) do not support sustained mangrove growth. Many newchannels have been dug throughout the main die-off area during the dry season of 2005.It will be interesting to observe the forest's response to this network of small flushingcuts.

The count and mean height (in feet) of trees 6 feet and above in each of the plots(Table l) demonstrates that the control plots (Plots 9, 10, and 11) are dominated byfewer but more large trees. Hurricane Wilma (Figures 3a and 3b) seems to haveknocked over many large trees in the forest. These photos were taken about one weekpost Wilma. Some of the monitoring plots were visited...not all of the tall trees weredown but there was major damage throughout the entire project. Floraquatics, Inc.crews cleared downed trees and branches from the flushing cuts and the forest flooraround the Strand seemed dry compared to the conditions during the 2005 survey.

20011999 2000 2003 20042002 2005

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Plot


Figure 1. Plot 1, October 2005.

Figure 2. Plot 2, September 2005

25


Figure 3. Plot 3, October 2005

Figure 4. Plot 4, October 2005.

26


Figure 5. Plot 5, September 2005.

Figure 6. Plot 6, September 2005

27

Figure 7. Plot 7, September 2005.


Figure 8. Plot 8. September 2005.

28

29Clam Bay Restoration and ManagementBiological MonitoringTurrell & Associates, Inc.: Sixth Annual ReportLewis Environmental Services, Inc.: Report #9November 2005

Figure 9. Plot 9 (control), September 2005.

Figure 10. Plot 10 (control), September 2005.


Figure 11. Plot 11 (contol), September 2005.

30

Clam Ray Restoration and ManagementBiological MonitoringTurrell & Associates, Inc.: Sixth Annual ReportLewis Environmental Services, Inc.: Report #9November 2005

3.0 SEAGRASSES

3.1 Methodology

Seagrasses are a valuable biotic indicator of environmental health and Clam Bayhas recognized the value in maintaining viable beds. The original permitteddredging design entailed impacts seagrasses within the channel between OuterClam Bay and Clam Pass. Monitoring over the life of the permit will allowquantification of the regeneration of those losses and follow the effect ofincreased tidal flushing on seagrass aerial coverage and density.

Methods include examination of aerial photographs and ground truthing by in-water and wading surveys. Accurate estimation of seagrass coverage is primarilyhampered by visibility so that the most effective survey time is at low tide.However, at low tide, several areas in the system are exposed rending coverageestimation more difficult. Best effort was made to overcome those obstacles.

Coordination with DEP staff resulted in a system of transects being established asdepicted on the enclosed map (Figure 4). The transects were traversed, swimmingwhere possible to avoid disturbing the sediment or walking were necessary and a1 m x lm quadrat placed at designated locations along the transects. Thefollowing data was recorded for each quadrat:

Percent coverage by sea grasses and/or an estimation of blade number per 10cm square,Sea grass species composition,Epifauna or visible infauna.

3.2 Seagrass Data

Results from transects 1-4 are described below while results from individualquadrats along transects 5-9 are graphically shown along with transectdescriptions on the following pages.

Outer Clam Bay: eastern and southern sectors, Transects 1 and 2

Observations revealed that while there was again no seagrass present alongTransect 2, there was still one area of Halophila noted along Transect 1 whichhad been barren until last year. The survey took place at mid tide and water depthswere no more than 2.5 to 3.0 feet with visibility of only a few inches. A tunicatewas observed along Transect 2.

Clam Bay Restoration and Management 32


Outer Clam Bay: northwest sector. Transect 3

Shoal grass has still not reappeared in this transect. This year, Red algae werenoted as opposed to the Blue-green algae noted before. The Red algae coveredgreater than 50% of the plot.

Channel just south of the boardwalk, Transect 4

This transect had no seagrasses at the time of the survey, which is the same asnoted last year. This maintains the downward trend in coverage from previousyears. However, some oysters were observed in the area which had not beenpresent in previous years.

GULF OF MEXICO

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MANGROVES

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,1 QUADRAT NUMBERS

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Marine & Environmental Consulting9584 Eanbange Ave. Suite B, F). 33042Phone: (941) 843-0188 Fax: (941) 843-8632

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This transect did not have any grass last year, but did have about 10% coverage at plot 5 thisyear.

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1 2 3 4 5 6 7 8 9Quadrat number

TRANSECT 6

This transect continues to have a fair amount of grass, primarily between plots 3 and 5. Afterplot 5, the growth begins to get smaller and disappears. The location of grasses has been shiftingaround for the last few years, but continues to have reasonable coverage. Last year the mostgrowth was noted between plots 4 and 7. The growth pattern is patchier at the south end and getsmore consistent toward the north, near plot 5. Oysters were noted at plot 9.



100 -190

4) 80> 70

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30 -a 20 -

10 -0

1 2 3 4 5 6 7 8

Quadrat number

TRANSECT 7

This very shallow transect still has larger concentrations of grass in the southern end of thetransect. There is a lot of variation in coverage between the plots, as has been noted in pastyears. In particular there was the most variation between plots 3 and 5. However, overall itseems that there is significantly more grass this year than last year. This brings the amount notedin this transect this year closer to how it looked in 2003, though perhaps patchier.



100

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100

1 2 3 4 5 6Quadrat number

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This transect has again spread out it coverage, whereas last year there was only a highconcentration at plot 1, and none elsewhere. Red algae were noted near plot 5. No grasses wereseen on the west side of the channel, which is consistent from past years.

Clam Bay Restoration and Management 3t


100908070o

(.) 60-ti 50 -cD 40tf, 30 -a 20

10-0

1 2 3 4 5 6

Quadrat number

TRANSECT 9

The growth on this transect has shifted configuration significantly, and has slightly more overallcoverage. Previously there was primarily only growth at plots 3 and 4, and the amount had beendecreasing. The grass noted at plot I was short, and was located very close to the mangroves.



4.0 SYSTEM OVERVIEW

4.1 Aerial Photography

Examination of low-level oblique aerials is the most effective method for determiningareas of stress and concern. A full mapping and acreage calculation was carried outduring the first survey in 1999, and reassessed in subsequent years. The extent of the die-off area was estimated again this year by digital mapping and interpretation of the aerialphotographs and the results are shown on the map at the front of this report (see page 6).Aerial photographs with follow-up groundtruthing were used to locate dead, stressed andrecovering areas. A selection of these photos is presented below with appropriateexplanations. Please note that these observations are based on photos taken in 2005before Hurricane Wilma, in order to more accurately describe how conditions had beenprogressing. A post-hurricane discussion follows this section.

Die-off area in 2003

Die-off area 2005



An area of thin canopy first noted in 2003 was still apparent this year from the infraredphotograph. This area is a little north of the Commons just off the berm. Field analysisof the site revealed that what appeared from aerial view to be a stressed area was actuallya location of heavy exotic (Brazilian pepper) and vine removal conducted earlier in theyear. A few mangroves seem to be stressed or dying in this vicinity. Leaf loss andgeneral thinning of the canopy continue to be observed. Some ponding of water is alsoapparent and ongoing site visits will continue to monitor this area. Leather fern and othergroundcovers still appear to be taking advantage of the extra sunlight but no appreciablemangrove regeneration has been noticed.

2004

2005



Below are photos of another stressed area noted in 2003. We have compared this year'saerial photos to those taken the past two years. It seems that this area has recovered to thepoint that stress is barely visible from the aerial.

2003

2004

2005

Another area of concern that became apparent last year was recovering notably. Thesmall area just to the east of the Contessa condominium in Bay Colony experienced arapid die-off due to an old channel that had not been maintained. The channel was re-opened last year and you can see below that the area had filled back in since the 2004photo. Since Hurricane Wilma, many areas along the strand and Bay Colony experiencedsevere shock evidenced by browning and loss of leaves. Most recent observations showthat leaf regeneration is occurring and the recovery of these areas will be monitored insubsequent reports.



Bay Colony 2004

Bay Colony 2005

One new area of die-off was noted this year, which we believe was due primarily to theclogging of an old channel that occurred during Hurricane Charlie. This area is near theCounty boardwalk, and you can see how the die-off follows the outline of the channelfrom under the boardwalk and out around the adjacent open water areas. The southernend of the channel has been cleared out and re-opened, and we will continue to monitorthe area for signs of continued deterioration or recovery. The northern end of the channelwas completely covered with beach sand from the storm and has not been opened. It isanticipated that the work done at the southern end will restore the flushing capability ofthis area and will prevent water levels from backing up too high in future events.

New 2005 die-off

Clam Bay Restoration and Management 43Biological MonitoringTurrell & Associates, Inc.: Sixth Annual ReportLewis Environmental Services, Inc.: Report #9November 2005

4.2 Hurricane Wilma

Hurricane Wilma hit the Naples area in October of 2005. The high winds causedsignificant leaf loss and felled trees throughout the Clam Bay preserve, as noted in ourmangrove plot descriptions. Additional aerial photographs were taken after the hurricanein order to assess areas that were more severely affected. The photos depict the leaf lossand general beating that the trees took as a result of the storm winds. We expect that thetrees will recover over time and will continue to monitor the entire system.

Plot 7, 2004


4.3 Mangrove Plots

The below photographs are of Turrell Plot #7. We highlighted this plot in previousreports because of the dense mangrove growth that has occurred in the last few years. In2004, the canopy coverage has reached a point where the larger new trees are beginningto shade out the smaller, weaker growth, resulting in more noticeable dead small saplingsand seedlings. This is a normal phenomenon that thins out the mid- and understoryallowing the stronger trees to have room to grow and become established with lesscompetition for food and light. This plot has been classified as recovering and continuesto progress in a healthy manner; however, the hurricane did strip leaves from most of thetrees and knocked down mangroves inside and around the plot. It is expected that thisplot should recover well from the storm damage.


Plot 8, 2004

In plot 8, shown above, you can see the increase in height of the saplings at the back ofthe photos between last year and this year. Groundcover is less obvious since it wasbrown at the time of the 2005 monitoring, which may have resulted from high water orstorm surge.


Plot 11, 2004

Plot 11, 2005

Plot 11 has seen considerable regrowth, which is difficult to illustrate in our photos due tohurricane damage. Last year the ground cover had diminished but seedling recruitmentand generation had started. Seedlings are primarily whites, covering about 85% of theplot. Other than the trees damaged by the storm, this plot continues to progress well.



Plot 11 aerial views

2004

2005

The main die-off area next to the strand continues to progress, though hurricane damagehas most likely set back the recovery process slightly. Mangrove saplings are now to 15or 20 feet tall in many areas. The fiddler crab and minnow populations remain high, andBatis continues to thrive as the dominant groundcover.

2004 from Strand wall

Post Hurricane Wilma

New Leaf Re'-growth after Hurricane



4.4 North Tram Station Replanting Area

This is the cattail area at the northern end of the berm where we have maintained cattaileradication efforts. We planted several species of native vegetation and several additionalspecies of have volunteered in the area since the original plantings. The photos belowclearly show that the vegetation has taken hold and is establishing itself well throughoutthe planting area.

2003

2004

View of planting area along berm, 2005



5.0 BATHYMETRIC MONITORINGCONCLUSIONS AND RECOMMENDATIONS:

The initial dredging of the flood shoals in 1999 and maintenance of the flood shoalchannel in 2002 has resulted in significant improvement to the stability of Clam Pass.These improvements to the hydraulic stability of the inlet from the April 1999 dredginghave persisted, however, the inlet channel and flood shoal areas have accumulatedenough sand so that conditions are similar to those that existed prior to the maintenancedredging completed in January, 2002. Based on the June 2005 survey, there areapproximately 12,000 cubic yards of sand within the currently permitted dredging limits.There are approximately 9,000 cubic yards in Segments B and C which were dredged inJanuary 2002. This sand is expected to be beach quality.

It has been nearly 4 years since the previous maintenance dredging. Although the tidaldata show that flows through the inlet are still significantly stronger than the pre-1999conditions, and may be sufficient to maintain flushing to the bay for the time being, thereare indications that the flow through the inlet has diminished somewhat since the 2002dredging. In order to reduce the potential for tidal exchange becoming diminished to thepoint where flushing might be inadequate, planning for the next maintenance dredgingevent is recommended. In planning for the next maintenance dredging, there are severalthings that should be considered.

Hurricane Wilma impacted this area since the June 2005 survey. While storm waveenergy often contributes to inlet shoaling by increasing sand transport into the inlet,strong tidal flow associated with a storm surge and storm water runoff tends to scour sandout of the channel. To provide updated information upon which to base decisionsregarding dredging and estimated dredge quantities, it is recommended that a post stormsurvey be conducted. If the post storm survey indicates that dredging should be done, thesurvey data would be used to prepare plans for bidding and for submittal to DEP for aNotice to Proceed.

There has also been some discussion about Collier County expanding the dredging toinclude the ebb shoal for the purpose of obtaining additional sand for the nourishment ofthe Clam Pass Park beach south of the inlet. This approach would provide immediaterelief to the erosion problem on the park beach; however, it also may have longer-termconsequences that should be carefully considered. A common impact from dredging inletebb shoals is increased erosion of adjacent beaches. This occurs for several reasonsincluding; interruption of natural transport which relies on the presence of an ebb shoal tobypass the inlet, diminished protection from waves for areas close to the shoal, and thereadjustment of dredge cut slopes to a natural repose angle as the shoal begins to reformby trapping sand from the littoral system.



It is recommended that if plans are developed for dredging the ebb shoal, those plansshould include a contingency plan for addressing impacts that might occur from thedredging. A DEP permit would be required for this activity, and it is likely that acontingency plan would be included as a condition the permit if such a permit is issued. Ifthe proposed plan to dredge the ebb shoal is to be implemented within the next year,maintenance dredging of the inlet in 2005/2006 under the current management plan isprobably not necessary.

It is not anticipated that dredging of the ebb shoal will have any adverse effect on theflushing of Clam Bay or on the mangrove communities in the Clam Bay system.

Recommendations for Ongoing Monitoring:

The tidal ranges and phase lags are an important indicator of how well tidal flow throughthe inlet is flushing the bay system. This data is presented in Figures 6, 7, and 8. Whilethese figures illustrate the improvements that have resulted from implementation of theClam Bay Restoration and Management Plan, they also show that there is a significantamount of scatter in the data. For example, the most recent data shows an increase in thehigh tide phase lag, which is an expected consequence if shoaling in the inlet issignificant enough to adversely affect tidal flow. However, during the same monitoringinterval, the low tide phase lag decreased, which is normally an indicator of improvedtidal flushing.

These inconsistencies have previously been treated as random scatter in the data becausethey are relatively small in comparison to the overall flushing improvements. Thisrandom scatter might be related to factors such as wind influence on tidal flow, or stormwater outflow. However, the scatter makes it difficult to identify trends that wouldindicate correlations between shoaling in the inlet and flushing action. It is thereforerecommended that the tidal data collection program be expanded to include datacollection at two additional stations to provide a level of redundancy that should behelpful in understanding the variability that has been fairly consistent in the data for sixyears.

The Clam Bay Restoration and Management Plan has so far been successful inmaintaining a maintenance dredging interval of up to 4 years. This representsconsiderable cost savings over more frequent dredging, and this cost savings isconsidered justification for the additional data collection and analysis which may be usedto improve management practices. With better understanding of how shoaling in the inletinfluences the tidal parameters, it may be possible in the future to base scheduling ofmaintenance dredging on tidal measurements alone, and thereby reduce the cost ofsurveys for monitoring shoaling in the inlet.



Previous Recommendations:

Recommendations made in previous reports that are still considered relevant to long termmanagement are repeated in this section for convenience.

The long-term management of the Clam Pass inlet system should include continuedmonitoring of the inlet channel from the gulf to the interior, as well as the meanderingconnecting channels and along the dredge cut within the Clam Bay system. The May2004 monitoring data show that cuts 1, 2 and 3, and the inner part of cut 4 have remainedrelatively stable since the 1999 dredging. It is recommended that continued monitoring ofthese areas be conducted once more in May 2006. If the sections appear stable based onthat survey, further monitoring of cuts 1, 2 and 3 should not be necessary during eachmonitoring event, and should possibly be only done at three-year intervals. This willreduce monitoring costs. However, due to the high recreational use of the inner bay areaof cut #4, monitoring should continue on two-year intervals between Station 18+00 and35+37. The tidal studies should be continued as an integral part of the annual monitoringbecause they will indicate when shoaling of the inlet and other channels has occurred tothe extent where tidal circulation in the bay system is affected.

Although dredging portions of the meandering channels between the four bays appears tohave contributed to improving the flushing of Inner and Upper Clam Bay, the tidalexchange remains relatively low at the north end of the system. If biological studiesindicate further enhancement to flushing of the remote northern portion of the hay systemis necessary, that may he accomplished by straightening sections of the meanderingchannel. This approach would necessitate removing small areas of existing mangrove andit would therefore be necessary to demonstrate that it would be beneficial to the broadergoal of managing the ecology of the overall bay system.


52Biological MonitoringTurret! & Associates, Inc.: Sixth Annual ReportLewis Environmental Services, Inc.: Report #9November 2005

6.0 WATER QUALITY SUMMARY

6.1 Sampling Results

The sampling data are not included in this report due to volume of pages making up thisinformation. All sampling information is available for review and inspection at the PBSDoffices. Field notes, Chain of custody records, and Laboratory reports are included in thisdata set. Of all the parameters, dissolved oxygen (DO), nitrates, phosphates, and totaldissolved solids, are discussed below. Discussion on these parameters is providedbecause they are the most indicative of potential water quality problems. The remainingparameters are not discussed because they all fall within normal and historic ranges forthe sample areas.

We also looked closer at monthly fluctuations as well as the annual averages in thisyear's report. The monthly information can show if a single or catastrophic eventcontributed to a high or low annual average and can assist in interpretation of the databeing presented.

Dissolved Oxygen (DO)

Dissolved Oxygen is a measurement of the amount of oxygen available in the water.Aquatic life depends on oxygen in the water and low levels can be an indicator of poorhealth of an aquatic system. Equipment problems that had plagued this testing in pastyears appear to have been resolved this year and valid DO readings were once morecollected for inclusion into this report. The measured DO levels fluctuated around theexpected and acceptable levels at all locations and no adverse or alarming levels wereobserved.

Nitrates (NO3)

Nitrates are nutrient components that are most often associated with fertilizers orvegetation decomposition. Excessive levels can lead to algal blooms, decreased DOlevels, and decreased viability of the system.

Nitrate values continue to fluctuate widely between sampling station and no appreciabletrend is apparent. It is clearly apparent that waters within the development itself, Samplelocations PB-13, St. Lucia, and to a lesser extent, PB-11, average higher values than thewaters of the estuary. This is still a good sign in that it means the water managementsystem and the vegetation between the berm and the pass is working to take up nitratesout of the water column prior to it going into the Gulf.

Looking at the monthly levels, another pattern is observed. PB-13 and the St. Luciastations seem to have periodic spikes in nitrate levels through the year. It is extremely



interesting to note that these spikes correlate very closely with spikes observed last year.Both the timing and the nitrate levels associated with the spikes are very similar. We aretrying to find out if these spikes are associated with lawn care activities such as fertilizingon the condominium or golf course grounds. As of the writing of this report, thisinformation had not yet been ascertained. Still, average levels are not extreme and asstated above, the water management system seems to be doing its job in removing thisnutrient component before it reaches the Gulf of Mexico.

Phosphates (0PO41

Phosphates are nutrient components like nitrates that are most often associated withfertilizers. Like the nitrates, excessive levels can lead to algal blooms, decreased DOlevels, and decreased viability of the system.

Ortho-phosphate values also fluctuate widely between sampling station however the trendthat started to become apparent last year is still progressing. It appears that waters withinthe development itself, especially sample locations PB-1 I. and St. Lucia are trendingtowards higher phosphate levels. There is a lot of fluctuation but for these sites, the highskeep getting a little higher and the lows don't go as low as previous drops. This could bean indication of phosphate accumulation in the system and is something that we want tocontinue to keep an eye on. It is a good sign that this trend is not apparent in the openwaters of the bay or pass. As with the nitrates, the water management system and thevegetation between the berm and the pass is working to take up this nutrient out of thewater column prior to it going into the Gulf.

The monthly pattern seen in the nitrate samples was not as apparent in the phosphatesamples but, both PB-1 1 and the St. Lucia stations show phosphate spikes that correlatewith Nitrate spikes. This could be another indication that these spikes are associated withlawn care activities such as fertilizing on the condominium or golf course grounds. Asstated with the nitrates above, the water management system seems to be doing its job inremoving this nutrient component as well before it reaches the Gulf of Mexico.

Total Dissolved Solids (TDS)

This is a measure of the mineral and salt content of the water. Generally, the higher theTDS content, the saltier the water. As with past years, this parameter was within thelevels expected. The freshwater sampling stations showed low TDS levels while theestuarine sampling stations showed higher levels. The one exception was a drastic spikeat the Glenview monitoring station in April. Since this is the last sampling periodassociated with this report, it appears as an anomaly when compared to the rest of thedata. Subsequent monitoring also indicates that this was a fluke reading most likelyassociated with sampling error or an equipment malfunction.



6.2 Conclusions

This year's testing did show that most parameters are still reacting as expected and thestorm water management system appears to be doing its job by tying up or removingnutrient and pollutant parameters before they reach the Gulf of Mexico. The phosphatetrend observed at a couple of stations warrants continued testing and observations. Inaddition, more investigative work will be conducted in the upcoming year to determine(if possible) the source of the spikes observed in both the nitrate and phosphorus levels.The results of these investigations will be commented on in future water quality reports.



7.0 CONCLUSIONS

7.1 Mangroves

The remaining die-off areas now encompass just over 24.7 acres per calculations made byTurrell & Associates Inc. In 2003, a portion of the die-off area (approximately 14 acres)was reclassified as recovering and due to the continued growth of new vegetation, thisclassification has not been changed and in fact, additional acreage (12 acres) has beenclassified as recovering this year. Several small new die-off areas and one larger die-offarea have been located within the system. The smaller areas are a result of new lightningstrikes and hurricane damage from Hurricane Charlie last year. Blown down trees openedup areas in the canopy that, while not dead, had much less canopy cover than in the past.The larger die-off area (approximately 1.5 acre) is also attributable to Hurricane Charlie.The die-off has occurred along an old flushing creek that was entirely blocked by bothsand and vegetative debris for a period of about 6 months. Once the adjacent mangrovesstarted showing signs of stress, the blockage was found and steps taken to restoreflushing. It appears as though the trend had been stopped but the recent passage ofHurricane Wilma may add to the die-off. We will be diligently monitoring this area in thefuture to insure that blockages do not occur and flushing is maintained.

All told, 3.14 acres have been added to the die-off area this year. A couple of the diffuseareas of stress in the system have been removed from the map as they no longer appear asstressed as in years past. Results from the monitoring plots give a picture of continuedgrowth of individual trees and consistent seedling recruitment.

The area around Turrell & Associates plot 7 was characterized as recovering, and thistrend has continued. This plot and Plot 8 have both shown the most growth in the pastyear with many trees now over 15 feet tall. The channel construction within otherportions of the Strand die-off area will allow continued seedling recruitment and Batiscolonization during the upcoming year. The existing plants continued to survive throughthe hurricanes and associated surges and in most places, though the leaves were battered,the trees themselves still survive. The channels cut throughout the area clearly help toflush the stacked water and return water levels to normal in a much shorter period of timethan would have occurred prior to 2001.

Groundtruthing of areas showing stress suggests that they are still areas of lowerelevation and ponding of water or lack of drainage may still be responsible for thecondition of these areas. In the northern area just west of the Marbella condominiumwhite filmy bacterial mats could still be observed in these low areas, suggesting thatwater is not moving in and out of the forest effectively.

Clam Bay Restoration and Management 56


While the hurricanes of 2004 did not do any major damage to the mangrove system hereat Pelican Bay the recent 2005 Hurricane Wilma was much more destructive to thesystem as a whole. Extreme leaf loss, browning, and limb/trunk breakages were apparentresults of the storms. Clean-up efforts occurred along the tram berm and boardwalks butthe majority of the system will be left to recover on its own. As shown in earlierphotographs, trees are already putting out new growth and show every indication ofrecovering from the storm damage.

Construction of the last component of the flushing channels was completed this year. Allof the major channel locations have been identified and dug. Monitoring of the newexcavated areas will continue to document the recovery that is expected now that thechannels have been finished.

These observations have been used to direct the focus for 2006 and budget potentialconsiderations for 2007, described in Section 8.0.

7.2 Seagrasses

Positive observations include the continued existence of small patches of Halodule toOuter Clam Bay. Seagrasses were seen along the transects in Outer Clam Bay were stillpresent during this year's surveys though they had not expanded any more. It alsoappears that the seagrass density along the flats adjacent to the pass has increased slightlyfrom the depressed levels noted last year.

Seagrass coverage is still lower than the 1999 pre-dredge conditions but the gradualdecline since the 1999 dredging does not appear to have continued this year. The lowercoverage is most likely an unforeseen consequence linked to the extended tidal range inthe bay. The increased tidal range results in an extended period of exposure of the mudflats at low tide. The poor water clarity means that grasses are mostly observed in areasof 2 feet or less in depth. Thus grasses in the channel prior to dredging were concentratedalong either side, hence transect placement. The change in topography has meant that themud flat areas would be drier for a longer period because of the increased periodicityseen since the dredging was done.

This is considered the most likely explanation for the decline in seagrass coveragealthough when the decline in Outer Clam Bay is also considered, water quality could be afactor. This is particularly relevant for transects 1 and 3 where the flap gate Seagateculverts may have reduced tidal exchange in Outer Clam Bay. The culverts were removedin October 2002, to determine if tidal exchange between Outer Clam Bay and VenetianBay can be accomplished without affecting Clam Pass. Monitoring showed that theculverts could remain off without affecting the Pass, so the culverts were left off. The re-appearance of seagrasses two years after the culvert removal may indicate that water



quality and flushing were a factor in the original decline of the grasses in this area thoughno appreciable expansion of seagrass coverage was noted this year in this area.Subsequent years of monitoring may support this theory if the seagrass densities continueto increase.

Another major component that could have affected seagrasses this year was the passageof Hurricane Wilma. The winds and storm surges associated with this storms moved a lotof sand around area beaches and could have impacted the grasses by covering them, byshearing them away, or by increasing turbidity in the water and reducing light penetrationto the grasses. Since the storm passed after this year's monitoring was conducted, it is notknown if the seagrasses were affected or not. Only continued monitoring will determineif impacts occurred.

As in the past couple of years we will be spot checking certain plots along the transects atdifferent times to determine if seasonal fluctuations could be affecting the survey results.It appears as though densities could be fluctuating within the area and we hope to be ableto determine maximum densities throughout the system.



8.0 Concluding Remarks and Management Focus for 2006

Recovery is occurring, evidenced by continued seedling recruitment and sapling survivalin the main die off area, Batis colonization, and growth of individual trees in monitoringplots. This year saw a direct hit from a major storm and the existing plants while batteredby the high winds, weathered this storm well. Still, there continue to be signs of stresswithin other forest areas and exotic vegetation has moved into some areas which showsthat this is a very complicated ecosystem and monitoring efforts must be ongoing in orderto properly manage the system. It will be a slow process before full recovery can beexpected and the work conducted this year demonstrates the importance of maintainingvigilance and a proactive approach towards the restoration efforts.

The channels dug within the die off area in the previous years and completed this yearhave averted possible extended flooding by late summer rains and a major hurricane.High numbers of seedlings and Batis recruitment are still being observed throughout thearea following the work. Within one of the stressed areas, observations of standing watersuggest that additional drainage may still be needed though tides and high waterthroughout the system may have biased these observations. The main work focus for2006 is the continued maintenance of the existing cuts and the possible planting of areasalong the berm where cattail eradication has been very successful.

A list of work items to be undertaken is presented below, some of this work is alreadyunderway, additional items may be addressed in the budget for fiscal year 2007 if theresults of next years work indicates additional work is needed;

Continue clearing of fallen trees within the main waterways of Clam Bay.

Exotic and Nuisance vegetation should continue to be removed. Brazilian pepperwithin the forested areas should be identified and treated. Old World Climbing Fernfirst observed last year is still present within the system and should be eliminated.

3) The cattail areas along the berm should continue to be monitored. Any indicationsthat water quality degradation is occurring due to overgrowth of cattails shouldtrigger a maintenance activity that will remove the decaying plant biomass from thesystem. The storm surge associated with the hurricane pushed more salt water into theberm and helped to keep the area cattails under control. It is possible now thatsupplemental plantings, similar to those installed at the northern end of the berm,could be installed to speed up the re-growth of the open areas left after the cattailremoval.

4) Conduct a post-storm inlet bathymetric survey to determine if the inlet was adverselyaffected by the storm and to determine if a dredging activity is needed prior to the



next sea turtle nesting season. (Our understanding is that the County may already bedoing this as part of their ebb shoal investigation)

Water Level Monitoring within inner mangroves will re-commence. Replacement ofseveral water level loggers within the mangroves and away from open water willmonitor daily and seasonal fluctuations in water levels. A clearer picture of the waywater within the system behaves can be established now that the flushing cuts havebeen completed.

Monitoring and maintenance of the flushing channels is essential to maintaining theadditional flushing capacity that they have contributed to the system.

Two additional tidal monitoring stations should be established to determine ifongoing inconsistencies in data collection might be related to factors such as windinfluence on tidal flow, or storm water outflow. The additional stations will alsoprovide a level of redundancy that should be helpful in understanding the variabilitythat has been fairly consistent in the data for the past six years.

Plan to conduct a pre-condition beach survey to the north of the pass should theCounty decide to try and dredge the ebb shoal outside of the pass. This backgroundinformation will be needed to monitor or determine if any adverse impacts to thebeaches north of the pass result from those activities.

9) Year-round monitoring of the system rather than once-a-year will continue. This willallow for closer scrutiny of the system and may catch problem areas while they arestill able to recover rather than after they crash.

The final word for 2005 is very similar to the last couple of year's prognosis. Efforts undertakento stop and reverse the die-off appear thus far to have been very successful. Continued efforts areneeded to quantify the response to measures that have been implemented, and to make sure thatthe measures implemented are maintained in the future to continue the recovery of the mangrovedie-off areas. The outlook for 2006 and beyond is optimistic and indications are that themajority of the system is on the road to recovery.

biological monitoring report - pelican bay...

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