Attachment_2_-_PDEP_-_GINS_Johnson_Beach_Restoration_Plan_-_May2024.pdf

Gulf Islands National Seashore – Johnson Beach

Dune Restoration & Enhancement

1. INTRODUCTION

The coastal dune ecosystem exists in dynamic environments where disturbances, whether natural or human-caused, can create significant, long-term changes to the system. Many parts of the coastal dune ecosystem across the Florida Panhandle have been severely damaged by tropical storms over the past 25 years. Human-caused disturbance exacerbates those issues at many of the same sites. Restoring vegetation is critical for the long-term resilience of the coastal dune system and to ensure those systems regain their natural biodiversity and ecological functions.

This restoration plan is part of a larger multi-year project to implement tightly focused restoration activities to improve habitat quality, connectivity, and resilience in the coastal dune ecosystem throughout its historical distribution in the Florida Panhandle. The project is a joint effort between the Florida Fish & Wildlife Conservation Commission (FWC), U.S. Fish & Wildlife Service (USFWS) Gulf Restoration Office and University of Florida (UF IFAS). All partners work collaboratively to ensure that project activities are strategic and focused on locations that will maximize plant diversity and dune resiliency, while minimizing potential conflicts with other coastal species.

Project objectives include:

• Restoring the historical heterogeneity of landscape features within the dune ecosystem

• Re-establishing connectivity of dunes in degraded areas where disturbance has created gaps or openings that severely affect vegetation, wildlife, or humans.

• Restoring or enhancing the natural diversity and richness of native dune vegetation

• Increasing the diversity and resilience of the coastal dune ecosystem to enhance various wildlife and vegetation populations that are dependent on them.

The success of site-specific restoration activities will be measured by assessing changes in the dune community relative to control sites (i.e., non-restored) and high-quality reference sites, both pre- and post- restoration. Other factors can be observed during vegetation monitoring as well to determine certain success of these projects such as wildlife movement/use or decreased erosion/increased resiliency.

2. FOCUS AREA DESCRIPTION

2.1 Setting

Perdido Key is a 15-mile barrier island in the western Panhandle of Florida, stretching from Pensacola Pass to Perdido Pass. Johnson Beach is owned and managed by the National Park Service as a unit of Gulf Islands National Seashore (GUIS). Johnson Beach is located at the far western end of the eastern end of Perdido Key in Escambia County within the national park. Gulf Islands National Seashore is America’s largest national seashore and includes over 160 miles of coastline across Florida and Mississippi. The Perdido Key unit/Johnson Beach encompasses almost 7.5 miles of beach, dune, interdunal swale, and scrub habitat along the Gulf of Mexico. This area is extremely important for the conservation of several state and federally listed species. Johnson Beach is also one of the busiest sections of GUIS for recreational use by visitors. Hundreds of thousands of visitors a year come to Johnson Beach, which has led to the construction of a large pavilion and a large parking lot. Human activities also lead to concerns about human disturbance in natural areas. Johnson Beach has also suffered high levels of erosion, from hurricanes and other tropical storms. For these reasons, Johnson Beach is a high-priority candidate for restoration through the Panhandle Dune Ecosystem Project.

Figure 1. Johnson Beach on Gulf Islands National Seashore property indicated by the star symbol.

2.2 Impacts

Perdido Key’s long-established dunes have been heavily impacted by tropical storms in recent history, including Hurricanes Opal (1994, Cat. 3), Ivan (2004, Cat. 4), and Dennis (2005, Cat. 4). Increased storm activity has shortened the duration of recovery windows for dune vegetation and subsequent sand accretion, resulting in more extensive damage from smaller storms like recent Hurricane Sally (2020, Cat. 2). The National Park Service has voiced great concern for the protection of their infrastructure, as the frequency and intensity of storms has increased due, in part, to factors associated with global climate change.

In addition, Johnson Beach has a large parking lot and pavilion area that were developed to accommodate the large influx of visitors to the park every year. With such a large crowd, there have been many issues caused by people walking through dunes and damaging vegetation by creating their own social paths down to the beach rather than following the designated access paths.

Perdido Key is also home to the Perdido Key Beach mouse (Peromyscus polionotus trissyllepsis), a critically endangered subspecies of old field mice only present along Perdido Key in small, vulnerable pockets. Johnson Beach is one of the few areas of conservation land on Perdido Key that has viable beach mouse habitat that supports a remnant beach mouse population. Perdido Key development has rapidly increased over the last 15 years and continues to do so which has isolated small populations of the Perdido Key Beach mouse in this remaining viable habitat. With this federally protected and state-listed species present, any dune restoration work involving planting and connecting vegetated areas together can increase presence and connectivity for beach mice.

2.3 Specific Needs

The development of Perdido Key has exacerbated issues with dune erosion coupled with increased frequency and intensity of major tropical storms. While this development is not directly present at Johnson Beach, some effects can be indirectly correlated with that. The construction of park infrastructure has had some impact on dune stabilization and growth as visitors choose to walk through vegetation and create undesignated walking paths. The addition of plants to fill in these visitor-made paths as well as to extend the dune face seaward will not only help control the erosion created by humans and any vehicles used by the National Park Service but will also create a front-line barrier against storm surge.

Figure 2. Example of pathways created by visitors through and around dunes.

Since Hurricane Sally in September 2020, foredune recovery has been promising, with revegetation at Johnson Beach even since the last site visit in early 2022. Even though there has been that positive change, this site is still affected by erosion year-round and is at risk of being severely damaged in the event of another large storm event. Following any large storm events that affect this area, the park is forced to close for several days and sometimes weeks just to remove sand and water from parking lots and other infrastructure. Planting species adept at sand accumulation will help increase the elevation of this site as well as protect the back dune areas from storm surge and excessive salt spray while filling in visitor-made paths that have impaired dune growth. Thus, increasing dune resiliency and structural protection for the park’s development and conserving beach mouse habitat in the foredunes and back dunes.

Figure 3. Current vegetation line in front of Park’s pavilions

Additional reasoning for the issues observed at Johnson Beach is the maintenance or absence of post and rope. The access paths that the park does have at this location have been widened exponentially by the thousands of tourists that visit the National Seashore each year. This project will be installing new post and rope around our project area after planting to assist with this issue and the National Park Service staff will be maintaining it. Additionally, some symbolic fencing will also be installed as a temporary, protective barrier for some of the plants. The addition and redesign of a defined public access path will aid in natural recovery of vegetation as well as protect restoration planting sites and prevent the issue we have seen from continuing to happen yearly.

3. RESTORATION AND ENHANCEMENT ACTIVITIES

The plans detailed below address restoration needs that have been identified at Johnson Beach within the Perdido Key project area and take into consideration the needs of other species that utilize beach and dune habitats, such as shorebirds and marine turtles. Prior to the initiation of these restoration activities, FWC and/or UF project team members will demarcate restoration plots, control plots, and reference sites with flagging, as well access paths that contractors shall use to enter and exit work areas.

3.1 Overview

All the planting work at Johnson Beach will be conducted seaward of the primary dune line and in front of park infrastructure. The restoration will be focused on resiliency within the park and protecting park infrastructure including the road, pavilions, and parking areas as well as back dune habitat. There are also benefits to beach mouse habitat as beach mice have been found to be present north of the road at Johnson Beach. Beach access points have cut off vegetation from growing any further and visitors creating their own paths down to the beach has disturbed vegetation. Since Hurricane Sally in 2020, the natural revegetation process has slowed and is not able to keep up with the constant human disturbance. Planting here will add to the vegetation needed to better reflect what the natural area should look like as well as protect the park’s infrastructure in the event of another storm. Gulf Islands staff has expressed that this area constantly experiences sand and water breaches of the road and parking lot. The addition of new vegetation should enhance dune building as well as stabilization of vegetation already present to assist with the issues they have been experiencing.

Figure 4. All Johnson Beach plots with ID numbers.

3.2 West Johnson Beach

3.2.1 Plot 1

Figure 5. Johnson Beach westernmost plot, plot 1.

For plot 1, the planting pattern from the row closest to the Gulf of Mexico going landward is three rows of bitter panicum, three rows of beach elder, three rows of sea oats, and three rows of gulf bluestem all at 18 inches on center with 18-inch spacing between rows. The back row of plantings is approximately 73 meters south of the Gulf Islands ranger station pictured in the above photo and the left end of the plot is about 7 meters from the property fencing of the nearby condominium. The plot does curve slightly to better contour where current vegetation is established but plantings should be along where the current vegetation line is. The entire plot extends approximately 294 meters in length from west to east.

Figure 6. Planting diagram for plot 1 at Johnson Beach.

3.2.2 Plots 2,3,4

Figure 7. Johnson Beach plots 2, 3, and 4

For plot 2, the back row of plantings will be about 12 meters away from the current parking lot. The pattern of species is the same as plot 1, however, there will now be 4 rows of each species repeated twice for the left side of the plot and repeated once for the right side of the plot. The pattern for the left side of the plot is four rows of bitter panicum, four rows of beach elder, four rows of sea oats, and four rows of gulf bluestem which is then separated by a 1.8-meter (6 foot) gap from another 16 rows of the same pattern and then another gap of the same size followed by another 16 rows of the same pattern.

This is reflected on the right side of the plot as well but only repeated once. All plants will be planted at 18 inches on center with 18-inch spacing between the rows of plants. On the east side of plot 2 along the access point, the full column is bitter panicum to better establish a walkway for visitors from the parking area. Plot 2 is about 83 meters in length from west to east. The western side of the plot with three blocks of plant rows is approximately 50 meters in length and the eastern side is approximately 33 meters in length.

For plot 3, the same planting pattern will be followed as plot 2 starting with four rows of bitter panicum, four rows of beach elder, four rows of sea oats, and four rows of gulf bluestem moving landward. On the western portion of the plot, this pattern is repeated once and the east-side repeats twice. These repeated blocks are separated (like plot 2) by a 1.8-meter (6 foot) gap from the other repeated 16 rows of plants. The west side of the plot is about a 32-meter segment while the east side is about a 13.5-meter segment. Plot 3 extends about 46.5 meters in length from west to east. The back row of bluestem on the east side of the plot is approximately 10 meters from the parking lot and then 18 meters from the western side back row of bluestem. On both the far west and far east sides of plot 3, the last column on each side is composed of just bitter panicum to better establish the walkway for visitors from the parking area.

For plot 4, the same pattern of planting is followed as plots 2 and 3. Starting from the row closest to the water going landward is four rows of bitter panicum, four rows of beach elder, four rows of sea oats, and four rows of gulf bluestem all planted at 18 inches on center with 18-inch spacing between rows of plantings. This pattern of 16 rows is repeated twice more and in between these blocks of 16 rows of plants, there is the same 1.8-meter (6 foot) gap between the repeated blocks. On both the far west and far east sides of this plot, the end columns are bitter panicum plantings to better establish the walkway for visitors from the parking area. Plot 4 is approximately 13.3 meters in length from west to east.

Between plots 4 and 5, there will need to be a maintained 15-foot open gap for visitors to the east of the newly constructed ADA boardwalk.

Figure 8. Planting diagram for plots 2, 3, and 4 at Johnson Beach.

3.3 East Johnsons Beach

3.3.1 Plots 5, 6, 7, and 8

Figure 9. Plots 5, 6, 7, and 8 at Johnson Beach.

For plots 5 and 6, the same planting pattern is followed as the above plots starting with the row closest to the Gulf of Mexico moving landward, plant four rows of bitter panicum, four rows of beach elder, four rows of sea oats, and four rows of gulf bluestem all at 18 inches on center with 18-inch spacing between rows of plants. On plots 5 and 6, this pattern is repeated once and separated by a 1.8-meter (6 foot) gap between the two blocks of 16 rows of plants. Plot 5’s far west and far east columns as well as plot 6’s far west column are composed of just bitter panicum to better outline an access path for visitors from the pavilions. The back row of plot 5 is planted approximately 18.5 meters south from the edge of the west pavilion or about 2 meters in front of current vegetation. The back row of plot 6 is also planted around 18.5 meters south from the edge of the east pavilion. Plot 5 is approximately 50 meters in length while plot 6 is about 26.5 meters in length from west to east. There is a gap between these two plots about 15-15.5 meters across. Plot 6 will connect and continue into plot 7.

For plots 7 and 8, the planting pattern is the same as the other plots with four rows of bitter panicum, four rows of beach elder, four rows of sea oats, and four rows of gulf bluestem all planted at 18 inches on center with 18-inch spacing between rows. The shapes of these plots are in meant to funnel people straight down to the beach rather than cutting off vegetation where the current primary dune line stands. Since the shapes curve up, the four rows of bitter panicum are on the inside directly along the access walkway. Plot 8 is approximately 5 meters south of the end of the GINS boardwalk while plot 7 is about 6 meters south of the exit of the GINS boardwalk. Both plots should extend a length of 45 meters running from north to south and including the curve.

Figure 10. Planting diagram for plots 5 and 6 at Johnson Beach.

4. FENCING

This section will outline the plans for adding temporary symbolic fencing along with the restoration plantings. All fencing at Johnson Beach will be symbolic fencing with regular maintenance because of the number of visitors to the park. The current plan will be to return to the site after the plantings have become established to install more permanent post and rope in place of the symbolic fencing.

4.1 Symbolic Fencing

Figure 11. Symbolic Fencing around plot 1 at Johnson Beach

Symbolic fencing should be installed around the entire front of plot 1 as well as along the sides and connecting into current vegetation in the dunes. The total length measured was 984.56 linear feet.

The symbolic fencing on the west end will assist with human disturbance from the visitor-made path and on the east side will help with foot traffic coming from the parking areas. The symbolic fencing should be installed along a 10-foot buffer around plot 1, which is reflected on this map.

Figure 12. Symbolic Fencing around plots 2, 3, and 4 at Johnson Beach

Temporary symbolic fencing should be installed completely around plots 2, 3, and 4. These areas will encase the restoration plots as well as the plantings that are already there. The current post and rope will be removed by NPS staff before contractors arrive so installing new fencing and later permanent post and rope will be on a clean slate. A total of 1,378.49 linear feet of symbolic fencing should be installed around these three plots and not interfere with existing vegetation, restoration plots, or park infrastructure. Fencing should be installed approximately with a 2-foot buffer around the restoration plantings. Technical specifications will be outlined for contractors and specify the materials needed.

Figure 13. Symbolic Fencing around plots 5, 6, 7, and 8 at Johnson Beach

Temporary symbolic fencing should be installed completely around plots 5, 6, and 7 and partially around plot 8. These areas will encase the restoration plots as well as plantings that are already there.

Just as above, the current post and rope that is there will be removed by NPS staff before contractors arrive. A total of 1,187.75 linear feet of symbolic fencing should be installed around or near these plots and not interfere with existing vegetation, restoration plots, or park infrastructure. The symbolic fencing should be installed approximately with a 2-foot buffer around the restoration plantings. Technical specifications will be outlined for contractors and specify the materials needed. Plots 5, 6, and 7 will be completely enclosed by symbolic fencing leaving a gap between the post and rope and pavilions to ensure park staff can move equipment through if needed. Plot 8 symbolic fencing will start at the current vegetation line and angle downwards to connect with the northwest corner of the plot. From there, the symbolic fencing will follow the plot around and curve at the same distance as the other plots (approximately with the 2-foot buffer). The symbolic fencing around plot 8 will then angle north to connect with current vegetation. Later, more permanent post and rope will replace this symbolic fencing.