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SEAGRASS MITIGATION PLAN

SANTA ROSA SHORES CHANNEL DREDGING PROJECT

November 2013 Revised March 2014 Revised April 2014

Prepared for:

Santa Rosa Shores Home Owners Association

Prepared by:

Wetland Sciences, Inc. 1829 Bainbridge Avenue

Pensacola, Florida 32507

and

CSA Ocean Sciences Inc. 8502 SW Kansas Avenue

Stuart, Florida 34997

Seagrass Mitigation Plan Santa Rosa Shores Channel Dredging Project ii

TABLE OF CONTENTS

Page

1.0 INTRODUCTION............................................................................................................ 1

2.0 DREDGING IMPACTS AVOIDANCE AND MINIMIZATION...................................................... 4

3.0 DREDGING IMPACTS UMAM ........................................................................................ 6

4.0 SEAGRASS MITIGATION ............................................................................................... 7 4.1 BASIS FOR SEAGRASS MITIGATION COMPONENTS .............................................7 4.2 Seagrass Mitigation Plan(SMP) COMPONENTS .........................................................8

4.2.1 Recovery of Propeller Scar Injury Areas............................................................9 4.2.2 Restoration of Seagrass Injury Areas ..............................................................11

4.3 MITIGATION UMAM SCORING .................................................................................13

5.0 SEAGRASS MITIGATION MONITORING ......................................................................... 13 5.1 MONITORING METHODOLOGY ...............................................................................13 5.2 Mitigation Success Criteria .........................................................................................14 5.3 Mitigation Success Contingency .................................................................................15

6.0 LITERATURE CITED ................................................................................................... 16

LIST OF TABLES

Page

Table 1. Summary of the proposed restoration activities by mitigation component and corresponding, sizes (ac), monitoring methodologies, and success criteria. ...................................................................................................................15

LIST OF FIGURES

Page

Figure 1. Proposed project location map................................................................................2 Figure 2. Proposed seagrass and seagrass habitat impact areas..........................................3 Figure 3. Severely propeller scarred region of the western access channel (Channel A)

(From: Labins, 2013). .............................................................................................5 Figure 4. Severely propeller scarred region of the center access channel (Channel B)

(From: Labins, 2013)................................................................................................5 Figure 5. Severely propeller scarred region of the eastern access channel (Channel C)

(From: Google Earth, 2012)....................................................................................6 Figure 6. Seagrass coverage within the proposed impact areas...........................................10 Figure 7. Propeller scar injury recovery areas......................................................................14

LIST OF EXHIBITS

Exhibit 1. CSA memo suggesting the practicality of seagrass transplantion in Santa

Rosa Sound

Seagrass Mitigation Plan Santa Rosa Shores Channel Dredging Project 1

1.0 INTRODUCTION

Wetland Sciences, Inc. and CSA Ocean Sciences Inc. (CSA) (Project Team) have been retained by Santa Rosa Shores Homeowners, Inc. (Applicant) to develop this Seagrass Mitigation Plan (SMP) associated with the Santa Rosa Shores Dredging Project located in Gulf Breeze, Florida on Santa Rosa Sound (Santa Rosa County) (Figure 1). The project team is led by Mr. Craig Martin (Wetland Sciences, Inc.), who has over –twenty years experience as a professional environmental expert, particularly working in northwest Florida. Other members of the project team include Dr. Mark Fonseca and Mr. Ray Dennis from CSA. Dr. Fonseca is widely recognized as one of the world’s leading authority in the restoration of seagrass ecosystems whose work includes the national guidance document, “Guidelines for the Conservation and Restoration of Seagrasses in the United States and Adjacent Waters” (Fonseca et al., 1998). Mr. Dennis has extensive large-scale seagrass restoration experience that includes ecological restoration design, implementation, compliance monitoring, and regulatory agency coordination on various seagrass mitigation/restoration projects throughout Florida and in the Caribbean.

Recreational boating and tourism has been on the increase over the last two decades (Schwenning, 2001) and has a direct impact on shallow water seagrass habitat from propeller scarring and grounding injuries. Vessel grounding and propeller scarring can be avoided if caution is used with appropriate training and attention to navigation. Although dredge and fill activities are recognized as major anthropogenic disturbances to seagrass communities due to removal (mortality) and/or burial (Fonseca et al., 1998), proper and controlled dredging can alleviate much of the turbidity caused by insufficient water depths within marked channels (Schwenning, 2001). Here, the applicant proposes to improve navigation of existing channels to minimize propeller scarring and vessel grounding (and their associated environmental impacts) in seagrass habitat adjacent to the channel.

Santa Rosa Shores was platted in 1958 and consists of over 300 canal front lots. The canals are generally deep enough to navigate internally, but an extensive shoal restricts access into the intercoastal waterway. The shallow waters over this shoal require vessels to throttle up, getting the vessels on plane reducing the draft, and transiting the bar at high speeds. This practice continues to degrade the seagrass community, and is unsafe. Previous studies in 2001 suggest that 2.61 acres of SAV were eliminated as a result of vessel ingress/egress. It is widely known that the continued exposure to prop wash and propeller impacts prohibit recovery by natural means.

Residents have sought approval for dredging access channels as far back as 1991. These requests were eventually denied due to a lack of the development and submittal of a substantive mitigation plan. During 2000, the residents once again attempted to solve the access problem by requesting approval of a channel configuration requiring 2.6 acres of seagrass impacts which entailed the excavation of an east west channel from the easternmost canal and providing a direct north/south orientation from the center canal system. The excavation of the east west component traversed relatively intact SAV communities, and the likelihood of boaters from the far west channel navigating eastward out through the central channel is suspect due to the fact that the general boating focus is westward toward Pensacola Pass. Although this navigational channel configuration reduced impacts, some of the impacts were focused on higher quality habitats, and it is anticipated that the western canal users would still use the previously marked channel and continually degrade the SAV resources. This application was denied during 2007 based on the applicant’s inability to provide reasonable assurance that the mitigation efforts would be successful.


The Applicant is seeking authorization from the Florida Department of Environmental Protection (FDEP) and the U.S. Army Corps of Engineers (USACE) to dredge a total of three areas of higher elevations to -5 feet (ft) mean lower low water (MLLW) within three existing access channels, impacting approximately 2.01 acres (ac) of seagrass and seagrass habitat (Figure 2) within the relatively shallow waters adjacent to the shoreline of the Santa Rosa Shores community. The residents utilize the three channels for access to other navigable waters in (Figure 2) Santa Rosa Sound.

To date, the Applicant has been unsuccessful in obtaining regulatory approval specifically for dredging activities relating to the dredging of the three channels despite the efforts of multiple environmental consultants and various project design alternatives. The only project-related permit approval was issued by the FDEP (23 August 2010) for a seagrass transplanting pilot study (Permit No.: 57-0203765-003-DF) involving the harvesting of shoalgrass (Halodule wrightii) and turtlegrass (Thalassia testudinum) which is again a strategy that will be part of the mitigation proposed here for channel dredging activities from a separate dredge and fill permit application (Application No.: 57-0203765-001-DF). As the Applicant has elected not to implement the approved seagrass transplanting pilot study, no further regulatory action is requested or anticipated by the Applicant for the review and/or approval of the aforementioned dredge and fill permit application (Application No.: 57-0203765-001-DF).

Figure 1. Site vicinity map


Figure 2. Seagrass limits and proposed seagrass habitat impacts

The purpose of this SMP is to provide appropriate compensatory mitigation means and methods necessary to offset the impacts to seagrass and seagrass habitat from the Applicant’s newly proposed channel-dredging activities. This SMP, as part of the Applicant’s latest channel dredging permit application, is unrelated to and independent of previous dredge and fill permit applications submitted by the Applicant to the FDEP and USACE.

As a precursor for the development of this plan, the Applicant’s project team followed criteria described in the national guidance (Fonseca et al., 1998) and evaluated all appropriate mitigation options. This evaluation involved a detailed review of freely available aerial imagery covering several years within Santa Rosa Sound and adjacent water bodies for the purpose of identifying potential restoration sites and options. Restoration site and option queries were also coordinated and discussed with members of Department staff and the National Oceanic and Atmospheric Administration’s (NOAA) National Marine Fisheries Service (NMFS). However, despite these efforts, there were very few viable mitigation options available that met established criteria. Therefore, similar to the Port Manatee Seagrass Mitigation Site 9B Restoration Plan associated with FDEP Consent Order (OGC No.: 05-2790), the applicant’s project team has developed a diversified plan as part of this SMP to address the limited opportunities within the project vicinity to serve as appropriate compensatory mitigation.

This SMP includes restoration techniques involving supplemental transplanting from the impact areas to donor locations in close proximity to the impact sites. These components include:


• Recovery of propeller scar Injury areas adjacent to channels (transplanting); • Restoration of seagrass injury areas (transplanting)

The development of the individual restoration component methods as part of this SMP are based on a combination of the freely available aerial imagery review, preliminary field assessments of the impact areas (Wetland Sciences, Inc.) and experience and understanding of seagrass restoration ecology by the Applicant’s project team. Additionally, the SMP which includes the individual restoration components, seagrass restoration methods, and the general approach for the uniform mitigation assessment method (UMAM – Chapter 62-345 Florida Administrative Code) evaluations of the proposed impact areas and restoration sites/methods were discussed and developed in consultation with FDEP and NMFS. However, the Applicant’s project team will need to conduct on-the-ground surveys to verify the proposed impact areas and restoration sites for final identification/selection of the mitigation components to be implemented. Upon approval by the FDEP of this SMP, the Applicant’s project team will complete these surveys for completion of a Seagrass Mitigation Implementation Plan (IP) for subsequent review and approval by the FDEP, prior to initiation of the mitigation activities. The IP will include as needed based on any substantive deviation from the submitted plan:

• Updated UMAM evaluation of the three proposed impact areas; • Updated UMAM evaluation of the Applicant selected restoration sites based on current field

conditions; • Location and acreage (based field survey using sub-meter DGPS) of the selected

restoration sites and seagrass donor beds; and • Number of proposed transplanting units by species.

2.0 DREDGING IMPACTS AVOIDANCE AND MINIMIZATION

The Applicant’s project team has conducted an analysis of the design alternatives including the number of channels; dredge depth and width, and the channel alignment, which resulted in the current channel-dredging design proposal. Dredging plans proposed by the Applicant have evolved in consideration of mitigating existing off-site impacts as well as avoidance and minimization requirements of marine resources within the project area.

Initial project designs included dredging depths to -5 ft MLLW for the entire length of the three existing access channels requiring impacts of almost four acres (3.88) of seagrass and seagrass habitat. Subsequent designs alternatives included a new channel running east/west for the purpose of eliminating up to two of the three existing north/south access channels. However, this new channel would have required impacts to seagrass beds that have not been exposed to same level of boating pressure as the existing severely scarred channels. Figures 3, 4, and 5 show the current extent of the severe, out-of-channel propeller scarring and resultant degraded condition of the seagrass beds within the three existing western (Channel A), center (Channel B), and eastern access channels (Channel C).


Figure 3. Severely propeller scarred region of the western access channel (Channel A)

(From: Labins, 2013).

Figure 4. Severely propeller scarred region of the center access channel (Channel B)

(From: Labins, 2013).


Figure 5. Severely propeller scarred region of the eastern access channel (Channel C)

(From: Google Earth, 2013).

The current channel-dredging proposal makes use of the alignment from the existing three access channels (Channels A, B, and C) that are severely propeller scarred to avoid impacts to the adjacent seagrass beds characterized by lesser degradation from boating activities. In contrast to the initial planning designs, the Applicant’s current design alternative proposes the dredging of three areas of higher elevation within the access channels to a depth of -5.0 ft MLLW. In further minimizing previous designs, the Applicant has reduced the channel width from 60 to 30 ft measured at the top of bank. This design alternative avoids and minimizes, to the greatest practicable extent, impacts to marine resources (2.01 ac) and is the minimum necessary for the safe access of the vessels owned by residents residing in the subject community.

3.0 DREDGING IMPACTS UMAM

As evidenced by Figures 2, 3, 4, and 5, the three dredging impact areas (Impact Areas 1, 2, and 3) totaling 2.01 ac are severely damaged from propeller scarring due to continuous utilization providing the only waterway access to and from Santa Rosa Sound into the private community. For the purpose of developing the UMAM evaluations as part of this SMP, these impact areas within the access channels were subdivided by seagrass species and coverage based on a preliminary field evaluation completed by members of the project team on August 14-17 2012 utilizing methods consistent with the Recommended Survey Protocols for Estuarine and Marine Submerged Aquatic Vegetation (SAV) related to Permitting Applications developed by Florida Fish and Wildlife Conservation Commission (FWC). The survey utilized watercraft and divers with a sub meter DGPS recording the extent of the SAV limits. Species identification


and coverage estimates within each of the seven sub-areas were estimated by through field observations, aerial interpretation, and review of previous SAV assessments.

Although, the project team is aware that star grass (Halophila engelmanni) has been previously identified by the FDEP and previous consultants within the project area only shoalgrass (Halodule wrightii) and turtlegrass (Thalassia testudinum) were observed within the subject impact areas during the recent site inspection (May 15, 2013). The following is a breakdown of the seven impact sub-areas by species and coverage:

• Western Access Channel – Channel A (Impact Area 1) o Impact Sub-Area A1: 15% coverage by mixed composition of H. wrightii and

T. testudinum o Impact Sub-Area A2: 40% coverage by T. testudinum

• Center Access Channel – Channel B (Impact Area 2) o Impact Sub-Area B1: 20% coverage by mixed composition of H. wrightii and

T. testudinum o Impact Sub-Area B2: 40% coverage by T. testudinum o Impact Sub-Area B3: 25% coverage by T. testudinum

• Eastern Access Channel – Channel C (Impact Area 3) o Impact Sub-Area C1: 0% coverage by seagrass o Impact Sub-Area C2: 50% coverage by T. testudinum

The project team used the “Seagrass Management Plan for Big Lagoon and Santa Rosa Sound” report developed by the FDEP and the U.S. Environmental Protection Agency Gulf of Mexico Program (2001) to provide a basis for accurately characterizing the “Location and Landscape Support” and “Water Environment” sections of the UMAM evaluations. That document provided regional specific focus on the management issues regarding seagrass communities as well as the environmental and human surroundings that impact them. With the human population increase in coastal areas, it is understood that anthropogenic impacts to seagrass habitats from nutrient loading (storm water runoff), light reduction (increased turbidity), phytoplankton blooms, boating traffic also increase (Fonseca et al., 1998). As indicated in the FDEP document, Pensacola Bay and the adjacent water bodies (i.e., Santa Rosa Sound) have been impacted by numerous sources of pollution that has diminished the natural biodiversity and productivity typically expected by a system of this size and complexity (Schwenning, 2001). Therefore, scoring within the appropriate sections of the UMAM was based on a system that has been described by the State as measurably less than optimal.

UMAM scores will be finalized as a result of surveys undertaken during the growing season of 2014, prior to the submittal of the construction permit to the Department.

4.0 SEAGRASS MITIGATION

4.1 BASIS FOR SEAGRASS MITIGATION COMPONENTS

The objective of the mitigation is to provide appropriate and sufficient compensation for the unavoidable impacts to seagrass and seagrass habitat from the proposed dredging activities associated with the project. Compensatory mitigation options for seagrass have changed little in over 60 years (Fonseca, 2011). Chief among the site selection criteria has been reaching an understanding of why a prospective site was currently devoid of seagrass. Identifying sites where direct human impact has caused loss of seagrass but also has since ceased to operate


has been key (see summaries; Fonseca, 1994; Fonseca et al., 1998; Calumpong and Fonseca, 2002).

Previous applications failed to provide reasonable assurances related to the applicability of seagrass transplantation efforts in Santa Rosa Sound. In an effort to provide relevant seagrass transplantation information,CSA scientists have provided a memorandum detailing the practicality of seagrass restoration in this particular scenario (Exhibit 1).

On-site mitigation is the preferred approach to recovering from injury to many natural resources. Based on our past experience with transplanting seagrasses in the Panhandle (Fonseca et al., 1987), we anticipate that full natural recovery would take at least 5 years but with active introduction of transplanted seagrass, we expect to reduce that recovery time to 3 to 5 years.

Vessel grounding injuries in seagrass beds have long been recognized as important and legitimate targets for off-site compensatory mitigation (Fonseca et al., 1998; Kirsch et al., 2005). Distinctive signatures of groundings, such as blow holes (Kirsch et al., 2005), found especially in proximity to in-water structures unfortunately provide many opportunities for corrective actions. While propeller scars associated with groundings may heal comparatively quickly (Fonseca et al., 2004), excavated blow outs do not and were the target of our vessel injury site selection. Moreover, because we expect better adherence to navigation within the channel once it is completed than the currently propeller scarred seagrass habitat outside of the proposed (30-ft wide) access channels should rapidly recover, within 3 years with supplemental transplanting.

Additionally, new dimensions of seagrass management and an improved understanding of seagrass landscape dynamics have provided new options for compensatory mitigation. The value of seagrass restoration and mitigation is now being measured in terms of recovery of lost ecosystem services (Fonseca et al., 2000). This means that the fundamental metric of seagrass value is expressed by a product of acreage and persistence (i.e., acre-years of service). Additionally, because of the application of economic principles (NOAA, 2000), seagrass acreage restored closer to the present suffers less from discounted service flows than acreage restored at some time in the future. Thus, finding ways to provide new, persistent seagrass acreage has emerged as the preferred means to offset impacts and maintain baseline service levels.

4.2 Seagrass Mitigation Plan (SMP) COMPONENTS

The Applicant’s project team determined that there were very few compensatory mitigation options within the vicinity that met published criteria. Therefore, similar to the Port Manatee Seagrass Mitigation Site 9B Restoration Plan associated with FDEP Consent Order (OGC No.: 05-2790), the applicant’s project team has developed a diversified plan approach as part of this SMP.

The two individual restoration components, discussed in detail below, include:

• Recovery of propeller scar injury areas adjacent to channels and in the nearby project vicinity;

• Restoration of seagrass injury areas

The development of the restoration methods for the individual mitigation components is based on a combination of the aerial imagery review, agency consultation, preliminary field assessments, experience and understanding of seagrass restoration ecology. Upon approval


by the FDEP of this SMP, the Applicant will finalize the field evaluations of the restoration sites necessary for preparation of the application for a construction permit for subsequent review and approval by the FDEP, prior to initiation of the mitigation activities.

4.2.1 Recovery of Propeller Scar Injury Areas

The Santa Rosa Shores is a canal front subdivision which accommodates access to Santa Rosa Sound for residents and the general public for boating and water orientated activities. The community has no public boat ramp, dock, and/or other landward access to the existing canals/basins and access channels, resulting in use limited almost exclusively to the residents of the private community. Indirect utilization of the access channels is by incidental recreational use (e.g., fishing) by non-Santa Rosa Shores resident boaters.

Currently, the three existing access channels (A, B, and C) have gated markers but the natural bathymetry of this area (-3.0 to -4.0 MLLW within and adjacent to the existing access channels) (Figure 2) of the Santa Rosa Sound limits the safe access by vessel owners residing within the community. Using the metrics as described in the “Scarring of Florida’s Seagrasses; Assessment and Management Options” (Sargent et al., 1995), these seagrasses within the existing access channels are classified as severely scarred (Figures 3, 4, and 5). Dredging the areas within the access channels to -5.0 ft MLLW and reducing the overall channel width from 60 to 30 ft (top of bank or level at seafloor) would facilitate the recovery of a narrow corridor paralleling each of the existing access channels totaling approximately 2.0 ac (Figure 6). The narrow seagrass propeller scar recovery corridors were subdivided into two classes (below) based on the existing seagrass coverage as determined by the project team for individual evaluation using UMAM (Section 4.3, Mitigation UMAM Scoring):

• Propeller Scar Recovery Area (0 – 24% Seagrass Coverage: 0.72 ac); and • Propeller Scar Recovery Area (25 – 49% Seagrass Coverage: 1.07 ac); and • Propeller Scar Recovery Area (50+% Seagrass Coverage; .022 acre).

The Applicant acknowledges that infrequent propeller scarring outside of the access channels may still occur after project implementation but with the improved navigable waters and channel marking, this will be de minimus and that by reducing the frequency and severity of scarring, the natural recovery, and enhanced habitat recovery via transplantation within the existing, severely propeller scarred areas as identified by this SMP is expected within 5 years.


Figure 6. Seagrass coverage within the proposed impact areas

This proposed channel depth, and configuration is sufficient to maintain and focus safe navigation within highly identifiable channels, and thus curtail ingress/egress within areas outside the access channels. the Applicant will permanently mark the three, navigable access channels (reduced from 60- to 30-ft wide) using a new gated marker system with an increased number of channel markers(150’ spacing) in order to clearly define the limits for safe vessel navigation and provide protection of the adjacent seagrasses and other submerged aquatic resources. The navigational channels will be marked with private aids to navigation, and SAV/shallow water markers. These provide a means of minimizing secondary and cumulative damage to SAV, and in effect maintaining and enhancing the vast majority of SAV resources within the Projects nearshore waters. In addition to the physical demarcation of the access channel, the residents of the community will take part in an educational program developed and proctored by the Applicant for the increased awareness of seagrass habitats and general boating safety.

The Applicant’s intention is to substantially increase the number of gates along with the addition of habitat signage. The number, location, and specifications of the channel markers and supplemental signage as well as the community educational program for seagrass habitat awareness will be developed by the Applicant pursuant to the requirements of the Florida Fish and Wildlife Conservation Commission and U.S. Coast Guard regulations. The


channel-marking plan will be provided to the FDEP as part of the application for an construction permit following the approval of this SMP.

4.2.2 Restoration of Seagrass Injury Areas

Restoration of seagrasses is no longer experimental but also does not lend itself to over-simplification (Fonseca, 2011). Therefore, the Applicant proposes that the transplanting activities will be accomplished by using the “Modified Shovel Method” (MSM) and Pneumatic Plugger Methods” (PPM) approved by the FDEP for the Port Manatee Seagrass Mitigation Project (FDEP Permit No.: 0129291-012-EM), Port Manatee Seagrass Remedial Action Plan (OGC No.: 06-1536), and Port Manatee Seagrass Mitigation Site 9B (OGC No.: 05-2790). These methods developed by Mr. Ray Dennis of the project team and were based on techniques referenced by Fonseca (1994) and Fonseca et al. (1998). These methods are specifically designed for successfully transplanting both the shallow rooted seagrass species (MSM – H. wrightii) as well as the more robust, deeply rooted species (PPM – T. testudinum) while preserving recoverability of selected donor areas.

As the dredging activities occur transplantation of viable seagrass units will occur concomitantly within the adjacent injury and propeller scar areas. If insufficient quantity or quality of transplants are available from the impact site the Applicant will utilize adjacent/nearby suitable natural seagrass communities for transplanting donor material as determined by the project team based on species composition and density as well as water depths. These donor areas will be located using sub-meter DGPS for FDEP approval as part of the review and application for the Individual permit. The relatively small size of the seagrass planting unit’s (PU) for both planting methods (MSM – 0.69 ft2 and PPM – 0.35 ft2) and the conservative spacing of 5-ft (1 PU collected per 25 ft2) between collected units will minimize any potential adverse impacts and reduce the time-period (one growing season) for the recovery of the donor beds. In order to further accelerate recovery of the selected donor areas, the open holes will be simultaneously filled with unvegetated sediment collected from the project upland dredging spoil disposal area or other FDEP approved source. No seagrass donor material, either H. wrightii or T. testudinum, will be destroyed during the transplanting activities.

As a conservative mitigation target, the Applicant is estimating for purposes of this SMP a recovery of 65% coverage by seagrasses within a period of 5 years and continued monitoring and management until coverage is achieved which is consistent to randomly selected SAV beds within the Project vicinity. The reference bed location and condition will be assessed and approved by regulatory authorities prior to designation as project reference sites.

This transplantation success criteria will not utilize supplemental transplanting of seagrass for determination of success.

Off-site selection of suitable restoration candidate areas is one of the most critical steps in developing a successful seagrass mitigation program (Fonseca et al., 1998). The suitability of the site for the establishment of seagrass will ultimately determine the success or failure of any seagrass transplanting treatments. If a site does not have coverage by seagrass and a reason as to why cannot be identified and/or a plan developed to overcome the factor(s) precluding the establishment and persistence of seagrass then the site must be rejected as a potential candidate for restoration (Fonseca et al., 1998).

As part of the development of this SMP, the project team first performed an intensive search including a detailed aerial review of available imagery for suitable restoration sites and


consultation with FDEP and NMFS staff. Of the sites devoid of seagrass coverage which were identified, many were eliminated for various reasons following Calumpong and Fonseca (2001) including but not limited to:

• Subject area not devoid of seagrass coverage for consecutive years and likely part of natural fluctuation in seagrass coverage (i.e., no identifiable anthropogenic cause);

• Although subject area could reasonably be attributed to anthropogenic cause (vessel and/or dock injury area) it may also be subject to repeated injury such as dock repair/rebuilding or high utilization area (boat ramp, channel, or active private dock);

• Subject area was apparently linked to existing violation and may already be subject to regulatory action.

The project team therefore identified sites due to the apparent visually detectable signature (consecutive years) and apparent cause (vessel groundings; apparent excavations in otherwise unbroken seagrass cover). However, detailed field studies are necessary prior to final site selection by the project team for development of the Individual permit following the approval by the FDEP of this SMP. Therefore, restoration site locations and final acreage estimates are not available for this conceptual mitigation component as part of this SMP.

The Applicant proposes the active restoration of vessel injury “blowouts” (Kirsch et al., 2005) as well as defined scars that are not proximal to or associated with potential riparian issues and or considerable engineering/protection solutions. These mitigation components are part of this Seagrass Restoration Plan, these vessel injury areas will be transplanted with seagrass planting units using the same methods and planting approach as described in Section 4.2.1.

For these off-site plantings, the Applicant will salvage donor material from the proposed access channels prior to dredging for use during the transplanting activities. If there is insufficient donor material within the proposed impact areas then the Applicant will identify other suitable sources of donor material as referenced in Section 4.2.2. These alternate donor areas will be delineated using sub-meter DGPS for FDEP approval as part of the submittal of an application for a construction permit.

The Applicant is conservatively estimating seagrass coverage of 65% within the restoration planting areas inside in a period of 5 years without supplemental transplanting of seagrass as a metric of success. Overall success will be achieved with SAV coverage consistent with approved reference beds as described above. Biannual monitoring will occur during the beginning of the growing season (May/June) and during the end of the growing season (Sept/Oct.) for the first five years, then annually during October for the final five years.

The Applicant will salvage donor material from the proposed access channels as described in Section 4.2.1. If all suitable donor material has been removed from the proposed impact areas and further transplanting is required for completion of this mitigation component, then the Applicant will identify other suitable sources of donor material as referenced in Section 4.2.2. These alternate donor areas will be delineated using sub-meter DGPS for FDEP approval as part of the application for a construction permit.

Similar to Sections 4.2.1 and 4.2.2, the Applicant is conservatively estimating seagrass coverage of 65% within the restoration planting areas inside in a period of 5 years without supplemental transplanting of seagrass as a metric of success.


4.3 MITIGATION UMAM SCORING

As referenced above in Section 3.0, the rationale and approach for the UMAM mitigation assessment scoring for the mitigation components as part of this SMP was based on aerial imagery review of multiple years of available imagery, preliminary field assessments of the impact areas, knowledge of the habitats within Santa Rosa Sound and experience and understanding of seagrass restoration ecology. UMAM scoring will be completed during the growing season of 2014 prior to the application of the construction permit. Scoring and assessments will be accomplished in consultation with FDEP and NMFS staff for the impact and mitigation components.

The project team will reference the “Seagrass Management Plan for Big Lagoon and Santa Rosa Sound” report developed by the FDEP and the U.S. Environmental Protection Agency Gulf of Mexico Program (2001) to provide a basis for accurately characterizing the “Location and Landscape Support” and “Water Environment” sections of the UMAM evaluations. The mitigation will focus on:

• Restoration of Seagrass Injury Areas (Transplanting) • Protection of adjacent resources • Education and Awareness

The actual acreage and locations for these mitigation components will be developed as part of the Individual Permit application following the FDEP approval of the impacts, mitigation, and UMAM scoring.

5.0 SEAGRASS MITIGATION MONITORING

5.1 MONITORING METHODOLOGY

Monitoring, as part of this SMP, will be performed for a period 10 years. The initial five years a June and October evaluation will be accomplished, and after the initial five years annually until success, as defined below, has been demonstrated. Restoration areas and/or sub-areas within the mitigation components that have achieved success will no longer be monitored.

Monitoring of the reference and transplanted restoration areas will be accomplished utilizing quadrat-sampling methodology. Quarter meter square quadrats will be used, subdivided into 100 equal (0.0025 m2 or 5 cm x 5 cm) sub-units for quantitative counts of seagrass shoots by seagrass species. The number of occupied cells is converted to meters squared of cover (i.e. 15 cells occupied = 15 percent coverage). Planted areas will be sampled at a density of up to 50, 0.25 m2, randomly located quadrats per 400 m2 (no less than 10 replicates per restoration site). Percent coverage within the reference and transplanted areas of seagrass by species will be calculated as the average of the percent cover observations for all of the replicate samples. Additionally, qualitative observations including the condition of the planting units will be recorded. All seagrass identified within the sampling quadrats will be quantified and utilized during the success criteria assessment regardless of species or source (transplanted, naturally recruited, or adjacent encroachment/expansion). Annual monitoring will continue until the success criteria, as defined below, has been achieved.

Monitoring of the internal propeller scar recovery areas and seagrass impact areas will be accomplished by selecting up to 10 individual representative propeller scars within the propeller scar recovery areas. The endpoints of these selected scars will be located using DGPS during


the first monitoring event for locating the scars during subsequent monitoring events. Similar to the approach referenced by Fonseca et al. (1998), a random selection of three locations per scar will be sampled over a 1-meter linear distance at a resolution of 0.0625 m2. Within these random locations, seagrass shoot density and cover will be recorded as described above. Propeller scars that are determined to reach the defined success criteria from any single monitoring event [minimum of two events] will no longer be monitored.

As part of the monitoring events, above and underwater still photos and video will be taken by the project team at each site and will be provided to the FDEP as part of the post monitoring reporting. Monitoring reports will be provided bi- annually for the first five years and annually for the remaining five years until overall mitigation success has been achieved.

Figure 7. Propeller scar injury recovery areas

5.2 MITIGATION SUCCESS CRITERIA

Mitigation success criteria relative to the restoration areas are based on the standard monitoring and evaluating success guidelines from Fonseca et al. 1998. Reference communities will be identified and areal coverage quantified. These will provide the restoration coverage success criteria. For purposes of this SMP, success is defined as follows:

• Areal coverage by seagrass meets or exceeds reference site conditions within any transplanted restoration area or portion of the transplanted restoration area, measured during a single monitoring event as described above in Section 5.1, without having received supplemental transplanting during the same growing season.


• Areal coverage by seagrass within all of the propeller scars monitored during a single monitoring event as described above in Section 5.1.

Table 1 summarizes the proposed restoration activities as well as the corresponding monitoring methodologies, and success criteria.

Table 1. Summary of the proposed restoration activities by mitigation component and corresponding, sizes (ac), monitoring methodologies, and success criteria.

Mitigation component Restoration activity Size

(acres) Monitoring methodology

Seagrass Success Criteria

(% Areal Coverage**)

Propeller Scar Recovery Areas

Seagrass Transplanting TBD*

Annual: Areal Coverage (Quadrat Sampling), Qualitative

Condition and Species

Based on reference community coverage

Seagrass Injury Restoration Areas

Seagrass Transplanting TBD*

Annual: Areal Coverage (Quadrat Sampling), Qualitative

Condition and Species

Based on reference community coverage

*The size and location of these areas will be developed by the project team as part of the Individual permit application process following the approval by the FDEP of this SMP. ** Areal coverage success will be based on reference site coverage comparisons 5.3 MITIGATION SUCCESS CONTINGENCY

Any restoration area or portion of that restoration area determined, based on the annual monitoring results, to not meet or exceed the success criteria threshold after 10 years following the implementation of the restoration activities may be subject to remedial actions. However, remedial actions will only be required if the total “Functional Loss” associated with the project has not been offset by an equal or greater amount of “Functional Gain” (No Net Loss) derived from successful restoration areas or successful portions of restoration areas a defined by the success criteria (Section 5.2).

Contingency options to address the unanticipated failure of one or more of the individual mitigation components and/or sub-areas within the restoration areas will include alternative restoration areas proposed by the Applicant as part of a Remedial Action Plan (RAP). The RAP will be developed as needed following the completion of the 10-year monitoring program proposed as part of this SMP. The RAP will include but is not limited to:

• Description/discussion of the current status of the successful restoration components and unsuccessful restoration components from the Individual permit including a summary of the mitigation deficit to be addressed;

• Location and acreage (based on field survey using sub-meter DGPS) of the selected remedial restoration (if transplants fail to live and reproduce vegetatively) sites and seagrass donor beds (as appropriate);

• UMAM evaluation of the selected remedial restoration sites based on current field conditions; and

• Description of proposed restoration treatment, which may include transplanting activities (number of proposed transplanting units by species).


6.0 LITERATURE CITED

Calumpong, H.P. and M.S. Fonseca. 2001. Seagrass Transplantation, pp. 425-444. In: Short, F.T., R.G. Coles, and C.A. Short (eds), Global Seagrass Research Methods. 473 pp.

Dupree, J. 2008. The most important fish in the sea. National Wildlife Federation. Internet website: http://www.nwf.org/News-and-Magazines/National-Wildlife/Animals/Archives/2008/The-Most-Important-Fish-in-the-Sea.aspx

Fonseca, M.S. 1994. A Guide to Planting Seagrasses in the Gulf of Mexico. Texas A&M Sea Grant College Program, TAMU-SG-94-60l. 26 pp.

Fonseca, M.S. 2011. Addy Revisited: What has changed with Seagrass Restoration in 64 Years? Special Invited Issue: Ecological Restoration 29(1-2):73-81.

Fonseca, M.S., G.W. Thayer, and W.J. Kenworthy. 1987. The use of ecological data in the implementation and management of seagrass restorations, pp. 176-187. In: M.J. Durako, R.C. Phillips, and Roy R. Lewis, III (eds.), Proceedings of a Symposium on Subtropical-Tropical Seagrasses of the Southeastern United States. Florida Marine Research Publication, No. 42. Florida Department of Natural Resources, Bureau of Marine Research.

Fonseca, M.S. W.J. Kenworthy, F.X. Courtney, and M.O. Hall. 1994. Seagrass planting in the southeastern United States: methods for accelerating habitat development. Restoration Ecology. 2:198-212.

Fonseca, M.S., W.J. Kenworthy, and G.W. Thayer. 1998. Guidelines for the conservation and restoration of seagrass in the United States and adjacent waters. NOAA COP/Decision Analysis Series. 222 pp.

Fonseca, M.S., B.E. Julius, and W.J. Kenworthy. 2000. Integrating biology and economics in seagrass restoration: how much is enough and why? Ecol. Engineer. 15:227-237.

Fonseca, M.S., P.E. Whitfield, W.J. Kenworthy, D.R. Colby, and B.E. Julius. 2004. Use of two spatially explicit models to determine the effect of injury geometry on natural resource recovery. Aquatic Conservation: Marine and Freshwater Ecosystems 14:281-298.

Kirsch, K.D., K.A. Barry, M.S. Fonseca, P.E. Whitfield, S.R. Meehan, W.J. Kenworthy, and B.E. Julius. 2005. The Mini-312 Program - An Expedited Damage Assessment and Restoration Process for Seagrasses in the Florida Keys National Marine Sanctuary. J. Coastal Research 21:109-119.

Myers, R.A., J.K. Baum, T.D. Shepherd, S.P. Powers, and C.H. Peterson. 2007. Cascading effects of the loss of apex predatory sharsk for a coastal ocean. Science 315:1,846-1,850.

National Oceanic and Atmospheric Administration. 2000. Habitat Equivalency Analysis: An Overview. National Oceanic and Atmospheric Administration, Washington, DC.


Sargent, F.J., T.J. Leary, D.W. Crewz, and C.R. Kruer. 1995. Scarring of Florida Seagrasses: Assessment and Management Options. Technical Report TR-1. Florida Department of Environmental Protection. Florida Marine Research Institute. St. Petersburg, FL. 46 pp.

Schwenning, L.M. 2001. Seagrass Management Plan for Big Lagoon and Santa Rosa Sound. Florida Department of Environmental Protection Ecosystem Restoration Section and U.S. Environmental Protection Agency Gulf of Mexico Program. 45 pp.


Exhibit 1

MEMORANDUM

Date: 17 April 2014

To: Heather Mason, Environmental Specialist, Northwest District Submerged Lands Environmental Resource Permitting, FDEP

Elizabeth Orr, Environmental Administrator, Northwest District Submerged Lands Environmental Resource Permitting, FDEP

From: Mark Fonseca, Ph.D., Science Director, CSA Ocean Sciences Inc. Raymond Dennis III, PWS, Senior Restoration Scientist, CSA Ocean Sciences Inc.

Re: Santa Rosa Shores Channel Deepening Project Seagrass Mitigation Plan – Seagrass Transplanting Practicability Opinion

BACKGROUND

This memorandum was prepared by CSA Ocean Sciences, Inc. (CSA), in coordination with Wetland Sciences, Inc., on behalf of the Santa Rosa Shores Home Owners Association (SRS HOA) to address the recent concerns expressed by the Florida Department of Environmental Protection (FDEP) regarding the revised Seagrass Mitigation Plan (SMP). The specific purpose of this memorandum is to address concerns regarding the practicality of transplanting seagrasses, including turtlegrass (Thalassia testudinum) in the northeastern Gulf of Mexico.

The seagrass SMP was developed by the Project Team (CSA and Wetland Sciences, Inc.) to provide the appropriate type and quantity of compensatory mitigation for the proposed impacts associated with the SRS HOA channel deepening project. The Project Team is led by Craig Martin (Wetland Sciences, Inc.), who has more than 20 years experience as a professional environmental expert, particularly working in northwest Florida. Other members of the Project Team include Mark Fonseca, Ph.D., and Raymond Dennis from CSA. Dr. Fonseca is widely recognized as one of the world’s leading authorities in the restoration of seagrass ecosystems and whose work includes the national guidance document, “Guidelines for the Conservation and Restoration of Seagrasses in the United States and Adjacent Waters” (Fonseca et al., 1998). Mr. Dennis has extensive experience in large-scale seagrass restoration that includes ecological restoration design, implementation, compliance monitoring, and regulatory agency coordination on various seagrass mitigation and restoration projects throughout Florida and in the Caribbean.

The Project Team’s understanding is that the FDEP’s primary concern is the negative perception associated with seagrass transplanting in the northeastern Gulf of Mexico. This perception may be due to the limited number of past projects in the area. This memorandum responds to these concerns by assessing the practicality of restoring seagrasses through transplantation in the Santa Rosa Sound area and the northern Gulf of Mexico in general.

Seagrass Transplanting Practicability Opinion 2 FDEP

SEAGRASS TRANSPLANTING

Seagrass transplanting in the Santa Rosa Sound area, as well as much of the northern Gulf of Mexico, involves shoalgrass (Halodule wrightii), turtlegrass (Thalassia testudinum), and to some degree manatee grass (Syringodium filiforme) and widgeon grass (Ruppia maritima) (Fonseca, 1994). Our discussion will focus on shoalgrass and turtlegrass as these are the species of primary concern for the SMP. It has been well-established that restoration of turtlegrass is a long-term process throughout its range. Nonetheless, experienced practitioners have successfully transplanted this species throughout Florida and the Caribbean. One of the largest examples of successful, large-scale seagrass restoration took place at Port Manatee (Palmetto, Florida) and was referenced in the aforementioned SMP. The successful portion of that mitigation program (covering more than 20 acres of restored seagrasses through transplanting) was lead by Mr. Dennis. The survival and expansion rates for both the transplanted turtlegrass (8-in. cores) and shoalgrass (9-in. × 11-in. sods) planting units exceeded the permit requirements for seagrass mitigation and remedial planting projects at the seaport. Results from the annual monitoring and reporting were verified and accepted by FDEP as well as the U.S. Corps of Engineers (USACE), and Port Manatee was released from further monitoring requirements based on those successes.

Nonetheless, turtlegrass has long been not recommended as the primary species in restoration projects because of its inherently low rate of vegetative expansion. The approach of “compressed succession” (Derrenbacker and Lewis, 1982) has instead been embraced, introducing faster spreading, pioneering species such as shoalgrass to provide initial coverage and site stabilization, ostensibly providing opportunities for turtlegrass to encroach and out-compete shoalgrass over time.

To our knowledge, comparatively little transplanting of turtlegrass has been conducted north of Tampa Bay. Active seagrass restoration programs such as that of Dauphin Island Sea Lab (http://ecosystemslab.disl.org/projects.htm) appear to focus on the faster spreading and brackish water species. Fonseca et al. (1987) conducted a transplanting study at a series of sites, two of which are located in St. Andrews Bay (near Panama City and Panama City Beach, Bay County). The study sites were transplanted with turtlegrass, shoalgrass, and manatee grass using the bare root staple method described in Fonseca et al. (1984). Results from the Fonseca et al. (1987) study indicated that, in addition to successful colonization and spreading by shoalgrass and manatee grass, turtlegrass planting units exhibited a high survival rate within the planted areas. The study confirmed the slow expansion rate by individual turtlegrass planting units. A similarly slow expansion rate also was observed in parallel studies (Fonseca et al., 1987) conducted in the Florida Keys, suggesting that the slow vegetative reproduction rate of turtlegrass was fairly constant through its distribution.

On a larger scale, there are no known reports of an inherent limitation to transplanting seagrass throughout its distribution worldwide. That is, studies from around the world demonstrate that where seagrasses occur, they are amenable to reestablishment after transplantation under conditions conducive to normal seagrass growth and survival. Similarly, seagrass transplanting has been successfully performed throughout the Gulf of Mexico and for shoalgrass as far north as North Carolina, which is the northern limit of its range. There, transplanting of shoalgrass has been successfully used in mitigation for decades. Although few attempts have been made to transplant seagrass in the northeastern Gulf of Mexico, there is no evidence nor any reasonable expectation that the region presents any globally unique characteristics that prevent seagrass reestablishment through transplantation. As always, understanding the biology of the seagrass being transplanted is critical and care must be taken to suitably handle and transplant any seagrass, thus use of experienced practitioners has been routinely recommended (Fonseca, 1994; Fonseca et al., 1998). Similarly, we conclude that there are no inherent limitations to transplanting seagrass in the Santa Rosa Sound area. Meeting site selection criteria and ensuring subsequent protection from disturbance and other safeguards are required to maximize project success (sensu Fonseca et al., 1998) as is the case in any restoration project.


The transplanting activities proposed by the SMP were specifically developed to be consistent with the FDEP Seagrass Conservation Plan for Big Lagoon and Santa Rosa Sound (2001) and in consideration of the restoration principles outlined by Fonseca et al., 1998. These considerations include the following:

• These species of seagrass (turtlegrass and shoalgrass) currently exist within the project area and are the same species that have been successfully transplanted elsewhere in the Gulf of Mexico, Caribbean and Atlantic Ocean using methods referenced by Fonseca (1994) and Fonseca et al. (1987, 1998).

• The transplanting methods and approach proposed as part of the SMP are based on the demonstrated ability of these plants to expand from carefully collected planting units in a staged manner. As referenced by the SMP, planting material would be salvaged from proposed impact areas and sustainably harvested from donor beds (Fonseca et al., 1994).

• As recommended by Fonseca et al. (1987, 1998) and Kirsch et al. (2005), the SMP proposes the use of areas that have been exposed to acute episodes of disturbance such as extensive and overlapping prop scars (areas outside the proposed 30-ft wide channels) and vessel groundings (individual vessel grounding areas).

• Adaptive management would be followed, which includes adjusting the transplanting approach (species, density, and method) based on actual field conditions. For example, the Project Team might first stabilize the site using shoalgrass, followed by a supplemental turtlegrass planting units at a lower density to speed up the natural succession (Derrenbacker and Lewis, 1982).

• Transplanting would be performed during the appropriate season. Given the shorter growing season of the northern Gulf of Mexico region, transplanting would be conducted at the earliest point at the beginning of the growing season (spring) to allow for the maximum period of time for recovery and growth prior to winter (slowed growth, senescence) (Fonseca et al., 1987).

• Transplanting would be done using planting techniques (developed by Mr. Dennis) based on proven methods (Derrenbacker and Lewis, 1982; Fonseca, 1994; Fonseca et al., 1984, 1994, 1998). The “Modified Shovel Method” (MSM) and Pneumatic Plugger Methods” (PPM) were approved by the FDEP for the Port Manatee Seagrass Mitigation and remedial transplanting projects. These methods are specifically designed to successfully transplant both the shallow-rooted seagrass species (MSM: H. wrightii) as well as the more robust, deeply rooted species (PPM: T. testudinum).

• As demonstrated by Fonseca et al. (1994) and during the Port Manatee Seagrass Mitigation and remedial transplanting projects, donor beds can be used and will recover within a single growing season without permanent or measurable damage. The relatively small size of the seagrass planting units for both planting methods (MSM: 0.69 ft2 and PPM: 0.35 ft2) and the conservative spacing of a minimum 5 ft (one planting unit collected per 25 ft2) between collected units minimizes any potential adverse impacts and reduces the time period (one growing season as observed) for donor beds to recover.

• Setting a realistic mitigation timeline and success criteria that considers the ecology of the seagrass species (growth rate for each species), and baseline conditions (coverage/density) of the nearby reference seagrass beds.


CONCLUSION

The SMP associated with the SRS HOA channel deepening project was developed by and would be implemented by a project team consisting of world renowned and regionally recognized coastal restoration experts. The individuals have relevant and significant experience and success specifically on seagrass transplanting projects within Florida and many other countries around the world. Moreover, the Project Team developed the SMP in close coordination with the FDEP and its Seagrass Conservation Plan for Big Lagoon and Santa Rosa Sound (2001) in applying ecological and fundamental restoration principles and practices for restoring seagrass communities. It is the expert opinion of the Project Team that there is no evidence to suggest that seagrasses cannot be successfully transplanted and beds restored in Santa Rosa Sound.

LITERATURE CITED

Derrenbacker, J.A. and R.R. Lewis. 1982. Seagrass Habitat Restoration, Lake Surprise, Florida Keys. R.H. Stovai (ed.) Proceedings 9th Annual Conference for Wetlands Restoration and Creation. Hillsborough Community College, Tampa, FL. pp. 132-154.

Fonseca, M.S. 1994. A Guide to Planting Seagrasses in the Gulf of Mexico. Texas A&M University Sea Grant College Program. Galveston, TX. TAMU-SG-94-601.

Fonseca, M.S., W.J. Kenworthy, K.W. Cheap, C.A. Currin, and G.W. Thayer. 1984. A Low-Cost Transplanting Technique for Shoalgrass (Halodule wrightii) and manatee grass (Syringodium filiforme). Instruction Report EL-84-1. U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS. 16 pp.

Fonseca, M.S., G.W. Thayer, W.J. Kenworthy. 1987. The Use of Ecological Data in the Implementation and Management of Seagrass Restorations. Florida Marine Research Publications Number 42:175-187.

Fonseca, M.S., W.J. Kenworthy, F.X. Courtney and M.O. Hall. 1994. Seagrass Planting in the Southeastern United States: Methods for Accelerating Habitat Development. Restoration Ecology 2(3):198-212.

Fonseca, M.S., W.J. Kenworthy, G.W. Thayer. 1998. Guidelines for the Conservation and Restoration of Seagrasses in the United States and Adjacent Waters. NOAA Coastal Ocean Program Decision Analysis Series No. 12 NOAA Coastal Ocean Office, Silver Springs, MD. 222 pp.

Kirsch, K.D., K.A. Barry, M.S. Fonseca, P.E. Whitfield, S.R. Meehan, W.J. Kenworthy, and B.E. Julius. 2005. The Mini-312 Program – An Expedited Damage Assessment and Restoration Process for Seagrasses in the Florida Keys National Marine Sanctuary. J. Coastal Research 21:109-119.

Schwenning, L.M. 2001. Seagrass Management Plan for Big Lagoon and Santa Rosa Sound. Florida Department of Environmental Protection Ecosystem Restoration Section and U.S. Environmental Protection Agency Gulf of Mexico Program. 45 pp.

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