An essential element to our coastal health
Barrier islands are unique ecosystems that function as more than just areas for tourism and recreation. These long, narrow, offshore deposits of sand/sediment, oriented to the mainland coast, serve as the first line of defense during storms that threaten coastal communities. These islands are very important for reducing the devastating effects of wind and waves and for absorbing storm energy. They also provide important marine habitat that supports commercially important fish species, as well as birds, sea turtles and other wildlife species.
Barrier islands are separated from the mainland by a shallow sound, bay, or lagoon. They are dynamic systems that are in a state of constant change, migrating and reshaped by the ongoing action of wind, storms, waves, tides and longshore currents. The amount of sand in a barrier island system changes with time. Sand moves into and out of the system and along the islands under the influence of the elements.
A well-developed barrier island system encompasses the outer edge of our Apalachicola bay. This barrier island complex lies roughly parallel to the mainland and is composed of four islands. St. George, Little St. George, and St. Vincent Islands are included within the Reserve boundaries, while Dog Island lies outside the Reserve boundaries, and is east of St. George Island.
St. George Island lies southeast of the mouth of the Apalachicola River and is the only barrier island within ANERR with a bridge connecting it to the mainland. The island is 20 miles long and roughly one-third mile wide. It consists of approximately 7,340 acres of land and an additional 1,200 acres of marsh. The eastern end of the island includes the St. George Island State Park. On the gulf side of the island is a narrow band of beaches and low-lying sand dunes that grade into mixed grassland, scrub, mesic and scrubby flatwoods and bayside marshes. In 2008, the reconstructed Cape St. George Lighthouse was opened to the public on the island. First built in 1833 on Little St. George Island, it succumbed to beach erosion in 2005. The St. George Lighthouse Association spearheaded the effort to salvage the pieces of the light and to reconstruct the lighthouse on St. George Island. Of all the islands, St. George is the most accessible and has been modified the most by development.
Little St. George Island (also known as Cape St. George) is an uninhabited barrier island that was formerly part of St. George Island, but was separated from the main island in 1954, when the U.S. Army Corps of Engineers constructed the ship channel known as Bob Sikes Cut. The island was purchased in 1977 under the Environmentally Endangered in order to protect it from development and to contribute to the protection of Apalachicola Bay. Little St. George Island is currently owned by the Department of Environmental Protection’s Florida Coastal Office and managed by the Apalachicola National Estuarine Research Reserve (ANERR). Little St. George Island is nine miles long and varies in width from a quarter mile to a mile. Various Indian cultures occupied these island for hundreds of years. Turpentine operations occurred from 1910-1916 and again from 1950-1956. Many of the pine trees on the island are cat-faced from these operations. Typically, fires ignited by lightning strikes are allowed to burn regularly throughout the island. ANERR staff maintain fire breaks around the Marshall House Field Station and outbuildings, protecting these structures during fires. The island consists of approximately 2,300 acres and is separated by St. George by Sikes Cut and from St. Vincent by West Pass, a natural inlet. The Island’s remoteness and wilderness qualities provide an opportunity to explore and enjoy a remnant of Florida’s original barrier island landscape.
St. Vincent Island, acquired by the federal government in 1968, is managed as a National Wildlife Refuge. The island is nine miles long and four miles wide and consists of 12,359 acres. The island is managed to preserve its high diversity of plant and animal communities and serves as a breeding site for endangered red wolves.
The barrier islands are dynamic and restless, always shifting and changing shape. They are an important part of the coastal zone and protect marshes and estuaries from the ocean’s energy. They provide feeding, nesting and nursery areas for many species. Each island has a complex set of forces that reinforce formation and change over time. The barrier islands protect the mainland, but are vulnerable as shown by dune erosion over the years. They are natural wildernesses that are unique and fragile.
For information on recreational opportunities on the barrier islands and within the natural habitats across Franklin County’s conservation lands, check out the Reserve's "Road Map to Recreation."
A Reserve course on landscaping for our area
Bay-friendly Landscaping is a course the CTP has started offering to help residents create a yard that does not pollute, offers habitat for wildlife, and protects the bay. The course uses UF/IFAS Extension Service’s Florida-Friendly Landscaping Program (or FFL), with a special focus on storm water and runoff awareness. Florida-Friendly Landscaping is such an important part of good stewardship that the Florida legislation has defined it as: “quality landscapes that conserve water, protect the environment, are adaptable to local conditions, and are drought tolerant.” In the Reserve’s Bay-Friendly Landscaping class, residents learned the basic techniques of Florida-Friendly Landscaping, and how these ideas could be applied to their own yards and lawns.
These techniques can be applied to yards in any part of the country. The ocean is downhill and runoff moves soil and debris from hundreds of miles away. This also moves chemicals it pick ups, like pesticides, leaked motor oil, and fertilizer. Much of a bay-friendly landscape focuses on catching or slowing storm water and trapping the pollution it is carrying before it reaches a stream or river.
The Reserve puts bay-friendly landscaping to the test on its grounds and butterfly garden using 3,000 gallon cisterns to catch rainwater. For residences, a more reasonable solution is using a rain barrel. A properly equipped rain barrel has a spigot at the bottom and a hose or overflow valve at the top. Placed under a downspout or the valley of a roof, rain barrels are a great way of reducing the water running off your property. Though not safe for drinking, the water is ideal for watering plants, or rinsing off shoes and garden tools.
If rain barrels are not practical, a rain garden or bioswale may be a solution. Both techniques hold storm water on the property instead of allowing it to run off, but they differ in scale. A rain garden takes advantage of a natural depression in the yard. Homeowners then add gravel or small stones and water tolerant plants that are able to survive under routine inundation while the storm water drains away. In Florida, plants like Blue Flag Iris and Muhly Grass work well for this, as they can survive short term flooding as well as drought. When dry, rain gardens look just like a normal flowerbed, and they cut down mowing, maintenance, and fertilizer. A bioswale is similar to a rain garden, but larger, and can be found draining water from the grounds of commercial buildings, or from several houses in a community.
The Reserves uses no fertilizer on its garden or grassy spaces, making the land safer for pets, small children, and visiting wildlife. Using native plants and well-adapted non-natives has helped as they are suited for the conditions and require no chemical assistance.
Pests are treated quickly before they become a widespread issue requiring a strong, unsafe pesticide to fix. Weeding by hand in groomed areas and allowing the weeds to grow with the grass on mowed areas keeps maintenance to a reasonable level. By spot treating with agricultural oils, large outbreaks of nuisance insects and fungi are prevented. Native plants help on this front because they attract helpful pest-controlling organisms like ladybugs and spiders.
The Reserve doesn’t have staff dedicated to groundskeeping or landscaping, and that’s the way we like it! Employees would rather spend time learning about our estuary system, or connecting with the people who come to visit us. Large mulched areas and “no mow” zones with native vegetation that make great habitat keep maintenance at a minimum.
The traditional large, green expanses of St. Augustine and Bermuda grass lawns have a high cost in time, water, and fertilizer. Replacing a traditional lawn with flowerbeds and shrubs reduces time and energy spent on yardwork. Some of the prettiest Bay-Friendly yards are where native plants have been allowed to take over and grow as they are meant to, blooming seasonally and bringing in butterflies, birds and
For information on Florida-Friendly Landscaping, visit floridayards.org. The University of Florida’s IFAS website is a great resource for landscaping questions, tips, and guidelines. The Native Plant Society of Florida also has a helpful online tool for selecting plants based on their native range and care needs.
Reserve’s effort to understand the bay’s food pyramid
In previous OysterCatcher articles, ANERR has highlighted a variety of projects that research staff at the reserve have been working on. Most have been related to things we can actually see and touch, such as turtles, birds, and fishes; however, this fall we decided to highlight some results of one of our System-wide Monitoring Program’s (SWMP) monthly nutrient sampling.
Typically, oceanic water tends to be nutrient poor. The reason why estuaries like Apalachicola Bay are so productive is because rivers, which naturally tend to be nutrient rich, act as funnels bringing a steady inflow of dissolved nutrients from far up in the watershed. Plants and other organisms upriver have decomposed, their nutrients have been dissolved in the water, and then flushed down the river. When those nutrients meet with the nutrient poor waters of the sea, macroscopic plants called phytoplankton are quickly able to capture those nutrients, and when they combine the nutrients with light energy, they make their own food in the process of photosynthesis. Just like the terrestrial world, the marine world constructs the base of the food web with plants. These plants are then fed upon by macroscopic organisms called zooplankton. There are different types of zooplankton. Some are vegetarian grazers, some are omnivorous grazers and predators, which feed on both plants and other zooplankton, and others are carnivorous, preying strictly on other zooplankton.
Each month, ANERR’s research staff make collections of water samples from selected sites in the bay to gather information on nutrient levels in varying forms of nitrogen and phosphorus (Figure 1). They also collect information on chlorophyll, which is a bi-product of photosynthesis, or what is commonly referred to by biologists as primary productivity. Results of our long-term data show that nutrient and primary productivity levels follow a similar pattern, with different parts of the bay having different concentrations (Figures 2a and 2b). We can also see that these levels decrease along a north to south bay axis. The farther from the river and distributaries, the lower primary production tends to be (Figure 2c). Season is also important for primary productivity in Apalachicola Bay. Lowest concentrations of chlorophyll tend to occur during the winter, but follow an opposite pattern with increasing productivity with increasing salinity (Figure 2d). This pattern is most likely because of an increased availability of light energy during the longer, more intense spring and summer days.
With just this information, it might seem that the more nutrients we have, the better it is for the bay, right? However, this case is not so simple. Just like too much food is bad for our health, too many nutrients can be harmful in coastal systems. This is why it’s very important to be mindful of additional nutrients from fertilizers being transported into riverine systems from agriculture and residential homes. Fortunately, anthropogenic loading of these nutrients into the Apalachicola Bay system is relatively low, and many of the excess nutrients that are added upstream can be filtered out by our important wetlands.
In the past year, research staff has undertaken a new project to better understand how the zooplankton communities in Apalachicola Bay respond to primary productivity. Each quarter, in conjunction with our nutrient sampling program, research staff use a special net to collect the macroscopic animals from waters in the bay. Preliminary results show that bay water is teeming with macroscopic life, but more data will be collected before we can draw any solid conclusions. If you’ve ever looked at the water in Apalachicola Bay and thought there was nothing in there, take a look at the image on the previous page. That’s what our reserve biologists see when they look at it under a microscope.
Interactive plant guide for on-site Nature Walk
Now that the weather is getting cooler, it is a great time to take a leisurely stroll on the boardwalks at the Nature Center. As always, we encourage you to slow down and use all of your senses to tune into the natural environment that surrounds you. This time of year, the squirrels are very actively preparing for winter. You might also spot some birds that you would not see at other times of the year, and there are lots of butterflies around. It has been over a year since we installed plaques with quotes from a variety of famous people on the subject of man and nature along the Nature Trail. These quotes are changed every few months, so even if you have read them before, make sure that you give them a second look when you visit again. We hope that you will find at least one that will inspire you to pause and reflect.
The Nature Trail section now has an interactive plant guide that identifies twelve of the more common species found along the trail. The guides can be found in pick up/drop off boxes at either end of the boardwalk. Trees, shrubs, ferns and marsh grasses are each identified with a picture and description. Descriptions include physical traits and some of the ways that the plant is used by animals and humans. A number on the guide for each species corresponds with a numbered oval placard next to a representative plant on the trail. I have seen kids using the guide like a scavenger hunt looking for all twelve examples on the trail and then reading the description aloud when they find the plant. Once you learn how to identify the plants, you can look for other examples as you continue your walk around the property and in other similar offsite habitats.
We are always striving to make your visits to the Nature Center fun and educational. While our aquaria and Bay Discovery room remain the core of our Center, there is something new to see in our rotating exhibit space every few months. Art from the Sea by Robert Simmons will be on display through February 25, 2017. Our new film is now playing in the theater and the Reserve Wednesday lecture series offers the chance to learn something new about our natural world on the third Wednesday of every month. The best way to stay up to date is to follow us on Facebook or watch for ads and flyers locally.