The Incredible Floridan Aquifer

The Incredible Floridan Aquifer

Pitt Spring in the Florida Panhandle is one of more than 1,000 freshwater springs in the state. Springs serve as ‘windows’ to groundwater quality, since the water that flows from them comes largely from the Upper Floridan Aquifer. Photo: A. Albertin

As Florida residents, we are so fortunate to have the Floridan Aquifer lying below us, one of the most productive aquifer systems in the world. The aquifer underlies an area of about 100,000 square miles that includes all of Florida and extends into parts of Alabama, Georgia and South Carolina, as well as parts of the Atlantic Ocean and the Gulf of Mexico (Figure 1). The Floridan Aquifer consists of the Upper and Lower Floridan Aquifer.

Figure 1. Map of the extent of the Floridan Aquifer. Areas in gray show where the aquifer is buried deep below the land surface, while areas in light brown indicate where the aquifer is at land surface. Many springs in Florida are found in these light brown areas. Source: USGS Publication HA 730-G.

Aquifers are immense underground zones of permeable rocks, rock fractures and unconsolidated (or loose) material, like sand, silt and clay that hold water and allow water to move through them. Both fresh and saltwater fill the pores, fissures and conduits of the Floridan Aquifer. Saltwater, which is more dense than freshwater, is found in all areas of the deeper aquifer below the freshwater.

The thickness of the Floridan Aquifer varies widely. It ranges from 250 ft. thick in parts of Georgia, to about 3,000 ft. thick in South Florida. Water from the Upper Floridan Aquifer is potable in most parts of the state and is a major source of groundwater for more than 11 million residents. However, in areas such as the far western panhandle and South Florida, where the Floridan Aquifer is very deep, the water is too salty to be potable. Instead, water from aquifers that lie above the Floridan is used for water supply.

There are actually several major aquifer systems in Florida that lie on top of the Floridan Aquifer and are important sources of groundwater to local areas (Figure 2):

  • The Sand and Gravel Aquifer in the far western panhandle is the main source of water for Santa Rosa and Escambia Counties. It is made up of of sand and gravel interbedded with layers of silt and clay.
  • The Biscayne Aquifer supplies water to Dade and Broward Counties and southern Palm Beach County. A pipeline also transports water from this aquifer to the Florida Keys. The aquifer is made of permeable limestone and less permeable sand and sandstone.
  • The Surficial Aquifer System (marked in green in the map in Figure 2) is the major source of drinking water in St. Johns, Flagler and Indian River counties, as well as Titusville and Palm Bay. It is typically shallow (less than 50 ft. thick) and is often referred to as a ‘water table’ aquifer, but in Indian River and St. Lucie Counties, it can be up to 400 ft. thick.
  • Not included in Figure 2 is a fourth aquifer, the Intermediate Aquifer System in southwest Florida. It lies at a depth between the Surficial Aquifer System and the Floridan Aquifer. It is found south and east of Tampa, in Hillsborough and Polk counties and extends south through Collier County. It is the main source of water supply for Sarasota, Charlotte and Lee counties, where the underlying Floridan Aquifer is too salty to be potable.

    Figure 2. A map of four major aquifer systems in the state of Florida at land surface. The Floridan Aquifer (in blue) underlies the entire state, but in areas north and east of Tampa it is found at the surface. The Surficial (green), Sand and Gravel (red), and Biscayne Aquifer (purple/pink) lie on top of the Floridan Aquifer. A confining unit (area in brown) consists of impermeable materials like thick layers of fine clay that prevent water from easily moving through it. Source: FDEP.

All of the aquifer systems in Florida are recharged by rainfall.  In general, freshwater from deeper portions of the aquifer tends to have better water quality than surficial systems, since it is less susceptible to pollution from land surfaces. But, in areas where groundwater is excessively pumped or wells are drilled too deeply, saltwater intrusion occurs. This is where the underlying, denser saltwater replaces the pumped freshwater. Florida’s highly populated coastal areas are particularly susceptible to saltwater intrusion, and this is one of the main reasons that water conservation is a major priority in Florida.

More information about the Floridan Aquifer System and overlying aquifers can be found at the Florida Department of Environmental Protection (https://fldep.dep.state.fl.us/swapp/Aquifer.asp#P4) and in the UF EDIS Publication ‘Florida’s Water Reosurces’ by T. Borisova and T. Wade (https://edis.ifas.ufl.edu/fe757).

Wild Turkey Biology and Habitat Management

Wild Turkey Biology and Habitat Management

Eastern Wild Turkey Gobbler in Gadsden County – photo by Shep Eubanks UF/IFAS

The above picture of a strutting Eastern Wild Turkey is a sight that many hunters look forward to seeing every spring here in the panhandle of Florida.  In order to manage wild turkeys and their habitat it is good to understand some basic facts about their biology.

Wild turkeys are considered a generalist species, meaning that they can eat a wide variety of foods, primarily seeds, insects, and vegetation.  They prefer relatively open ground cover so that they can see well and easily move through their surroundings, but they aren’t picky about where they live as long as it provides them year-round groceries and safety.  They are also a very adaptable species. Turkeys prefer low, moderately open herbaceous vegetation (less than three feet in height) that they can see through, or see over, and through which they can easily move in relatively close proximity to forested cover.  Such open habitat conditions help them see and avoid predators and these areas will typically provide sufficient food in terms of edible plants, fruit, seeds, and insects.

Wild turkeys are considered, ecologically, to be a “prey species” and have evolved as a common food source for numerous animals—seems everything is trying to eat them.  Turkey eggs, young (i.e.,poults), and adults are preyed on by such animals as bobcats, raccoons, skunks, opossum, fox , coyotes, armadillos, crows, owls, hawks, bald eagles, and a variety of snakes.  Being prey to so many different animals has shaped the turkey’s biology and behavior.  Turkeys experience high mortality rates and don’t live very long, on average, <2 years. They are particularly vulnerable during nesting and immediately after hatching.  Because of this high mortality, reproduction is really important for turkey populations to replace the individuals that don’t survive from year to year.  Wild turkeys have adapted to being a prey species in part, though, by having a high reproductive potential.  Hens have the capacity to lay large clutches of eggs.  If a nest is destroyed or disturbed, especially during the egg laying or early incubation period, the hen will often re-nest. Turkeys are also polygamous, with males capable of breeding multiple females, which further boosts their reproductive potential.

Turkey hen with poults foraging in a grassy field in Gadsden County – photo by Shep Eubanks UF/IFAS

Newly hatched turkeys, referred to as poults, need grassy, open areas so they can find an abundance of insects.  Such areas are usually the most critical, and often the most lacking habitat in Florida.  Under ideal conditions for turkeys, grassy openings would occupy approximately 25 percent of a turkey’s home range.  Additionally, it is of equal importance to have such openings scattered throughout an area, varying in size from 1 to 20 acres such that they are small, or irregular in shape, to maximize the amount of adjacent escape cover (moderately dense vegetation or forested areas that can provide concealment from predators or other disturbances).  Large, expansive openings (e.g., large pastures) without any escape cover are not as useful for turkeys since they generally will not venture more than 100 yards away from suitable cover.

Good habitat allows turkeys to SEE approaching danger and to MOVE unimpeded (either to move away from danger or simply to move freely while foraging without risk of ambush).  In other words, good habitat provides the right vegetative structure.  When thinking about habitat for turkeys, it’s good to always think from a turkey’s point of view….about 3 feet off the ground!  Turkeys like open areas where they can see well and easily move.

Burning pine land in Gadsden County to improve wild turkey habitat – photo by Shep Eubanks UF/IFAS

One of the best management techniques to manage vegetation structure and composition is prescribed fire.  Fire can be very destructive, but if properly applied, fire can be quite beneficial to wildlife and is one of the best things you can do for wild turkeys.  When applied correctly, fire has  many benefits. Some of the benefits of fire to turkeys and other wildlife include: control of hardwood by setting back woody shrubs and trees in the under story; improving vegetation height and structure; stimulating new herbaceous growth at ground level; stimulating flowering and increased fruit production in some plants; it improves nutritional value and increases palatability of vegetation.  All of this leads to increased insect abundance and fewer parasites in the environment.  Prescribed fire also has benefits for the landowner.  Applied properly and regularly, prescribed fire will reduce risk of catastrophic wildfire which can destroy a timber stand.  It reduces hardwood competition so favored pines grow faster and healthier; and reduces the risk of disease, particularly after a thinning or timber cut, by removing logging debris that would otherwise attract insects and disease-causing agents.  It can also help control invasive species, and best of all it’s the least expensive option on a cost per acre basis.

Gobblers in pine stand after burn – Game Camera photo by Shep Eubanks

Another good practice is simply mowing or bush-hogging. Even in areas that aren’t super thick (such as around forest and field edges, or seasonal wetlands), mowing and bush-hogging alone, even without fire, are beneficial as they have much the same effect on the habitat as fire.  Basically, you’re removing grown up vegetation and allowing light to reach the ground again. Within pine plantations, roads often provide some of the best, or only, turkey habitat simply because the surrounding vegetation becomes too dense so roads are used for feeding and moving throughout the area. In this regard, wide roads increase the amount of open habitat which provides lots of insects, seeds, and edible vegetation. They also reduce the opportunity for predators to ambush turkeys which can readily occur on narrow roads.  Having wide roads is a good land management practice that lets roads dry-out quicker so that they can hold up to traffic better.

If you have pine dominated timber stands on your property, proper thinning is not only good for turkeys, but it’s good for your stand. Young pine stands, particularly those in sapling or early pole stages, are often too thick for wild turkeys, except as escape cover.  They get so dense that they shade out everything underneath.  They may produce some pine seeds when they get older, but for most of the year, there’s nothing to eat and nothing to attract turkeys to the area.  For turkeys, thinning opens up the canopy and allows sunlight to reach the forest floor, which in turn stimulates plant growth of grasses, forbs and soft-mast producing shrubs.

If you have an interest in turkeys, do most management activities outside of the nesting season, which generally runs from the middle of March through June.  From a practical standpoint that is not always possible, so on the positive side, if a nest is destroyed (whether by predators or management efforts), a hen will quite often re-nest.  Also, the overall importance of management will often outweigh the loss of 1 or 2 nests.  The time that turkey nests are at a premium is when a turkey population is low or just trying to get established into an area.  In such cases every nest is valuable.

For more information consult with your local Extension Agent .

 

 

Aquatic Weed Control – Common Salvinia

Aquatic Weed Control – Common Salvinia

Common Salvinia Covering Farm pond in Gadsden County
Photo Credit – Shep Eubanks UF/IFAS Gadsden County Extension

Close up of common Salvinia
Photo Credit – Shep Eubanks UF/IFAS Gadsden County Extension

Aquatic weed problems are common in the panhandle of Florida.  Common Salvinia (Salvinia minima) is a persistent  invasive weed problem found in many ponds in Gadsden County. There are ten species of salvinia in the tropical Americas but none are native to Florida.  They are actually floating ferns that measure about 3/4 inch in length.  Typically it is found in still waters that contain high organic matter.  It can be found free-floating or in the mud.  The leaves are round to somewhat broadly elliptic, (0.4–1 in long), with the upper surface having 4-pronged hairs and the lower surface is  hairy.  It commonly occurs in freshwater ponds and swamps from the peninsula to the central panhandle of Florida.

Reproduction is by spores, or fragmentation of plants, and it can proliferate rapidly allowing it to be an aggressive invasive species. When these colonies cover the surface of a pond as pictured above they need to be controlled as the risk of oxygen depletion and fish kill is a possibility. If the pond is heavily infested with weeds, it may be possible (depending on the herbicide chosen) to treat the pond in sections and let each section decompose for about two weeks before treating another section. Aeration, particularly at night, for several days after treatment may help control the oxygen depletion.

Control measures include raking or seining, but remember that fragmentation propagates the plant. Grass carp will consume salvinia but are usually not effective for total control.   Chemical control measures include :carfentrazone, diquat, fluridone, flumioxazin, glyphosate, imazamox, and penoxsulam.

For more information reference these IFAS publications:

Efficacy of Herbicide Active ingredients Against Aquatic Weeds

Common salvinia

For help with controlling Common salvinia consult with your local Extension Agent for weed control recommendations, as needed.

New Artificial Reefs for the Florida Panhandle

New Artificial Reefs for the Florida Panhandle

Deployment of the El Dorado as an Artificial Reef

Panama City Dive Center’s Island Diver pulls alongside of the El Dorado supporting the vessel deployment by Hondo Enterprises. Florida Fish and Wildlife crews also are pictured and assisted with the project from recovery through deployment. The 144 foot El Dorado reef is located 12 nautical miles south of St Andrew Pass at 29° 58.568 N, 85° 50.487 W. Photo by L. Scott Jackson.

In the past month, Bay County worked with fishing and diving groups as well as numerous volunteers to deploy two artificial reef projects; the El Dorado and the first of the Natural Resources Damage Assessment (NRDA) reefs.

These sites are in Florida waters but additional opportunities for red snapper fishing are available this year to anglers that book for hire charters with captains holding federal licenses. Federal licensed Gulf of Mexico charters started Red Snapper season June 1st and continue through August 1st. Recreational Red Snapper fishing for other vessels in State and Federal waters is June 11th – July 12th. So booking a federally licensed charter can add a few extra fish to your catch this year.

The conversion of the El Dorado from a storm impacted vessel to prized artificial reef is compelling. Hurricane Michael left the vessel aground in shallow waters. This was in a highly visible location close to Carl Grey Park and the Hathaway Bridge. The Bay County Board of County Commissioners (BOCC) acquired the El Dorado, January 14, 2019 through negotiations with vessel owner and agencies responsible for recovery of storm impacted vessels post Hurricane Michael.

The El Dorado was righted and stabilized, then transported to Panama City’s St Andrews Marina by Global Diving with support from the Coast Guard and Florida Fish and Wildlife. Hondo Enterprises, was awarded a contract to complete the preparation and deployment of the vessel for use as an artificial reef.

Reefing the El Dorado provides new recreational opportunities for our residents and tourists. The new reef delivers support for Bay County’s fishing and diving charters continuing to recover after Hurricane Michael. Several local dive charter captains assisted in the towing and sinking of the El Dorado.

The El Dorado was deployed approximately 12 nm south of St. Andrew Bay near the DuPont Bridge Spans May 2, 2019. Ocean depth in this area is 102 feet, meaning the deployed vessel is accessible to divers at 60 feet below the surface.

The Bay County Board of County Commissioners continues to invest in the county’s artificial reef program just as before Hurricane Michael. Additional reef projects are planned for 2019 – 2020 utilizing Natural Resources Damage Assessment (NRDA) and Resources and Ecosystems Sustainability, Tourist Opportunities, and Revived Economies of the Gulf Coast States Act (RESTORE Act) funds. These additional projects total over 1.3 million dollars utilizing fines as a result of the Deepwater Horizon Oil Spill. Deployments will occur in state waters in sites located to both the east and west of St. Andrew Bay Pass.

Large Crane Deploying Artificial Reef Concrete Module

Walter Marine deploys one of nine super reefs deployed in Bay County’s NRDA Phase I project located approximately 12 nautical miles southeast of the St. Andrew Pass. Each massive super reef weighs over 36,000 lbs and is 15 ft tall. Multiple modules deployed in tandem provides equivalent tonnage and structure similar to a medium to large sized scuttled vessel. Photo by Bob Cox, Mexico Beach Artificial Reef Association.

The first of these NRDA deployments for Bay County BOCC was completed May 21, 2019 in partnership with Mexico Beach Artificial Reef Association, Florida Fish and Wildlife Conservation Commission, and Florida Department of Environmental Protection using a $120,000 portion of the total funding. The deployment site in the Sherman Artificial Reef Permit Area is approximately 12 nm south east of St Andrew Bay Pass at a depth of 78 – 80ft.

Patch Reef # Latitude Longitude
BC2018 Set 1

(6 Super Reefs and  4 Florida Specials)

29° 55.384 N 85° 40.202 W
BC2018 Set 2

(1 Super Reef and 4 Florida Specials)

29° 55.384 N 85° 39.739 W
BC2018 Set 3

(1 Super Reef and 4 Florida Specials)

29° 55.384 N 85° 39.273 W
BC2018 Set 4

(1 Super Reef and 4 Florida Specials)

29° 55.384 N 85° 38,787 W

In 2014, Dr. Bill Huth from the University of West Florida, estimated in Bay County the total artificial reef related fishing and diving economic impact was 1,936 jobs, $131.98 million in economic output and provided $49.02 million in income. Bay County ranked #8 statewide in artificial reef jobs from fishing and diving. Bay County ranked #3 in scuba diving economy and scuba diving was 48.4 % of the total jobs related to artificial reefs. Dr. Huth also determine that large vessels were the preferred type of artificial reef for fishing and diving, with bridge spans and material the next most popular. Scuba diving and fishing on artificial reefs contributes significantly to the county’s economic health.

For more information and assistance, contact UF/IFAS Extension Bay County at 850-784-6105 or Bay@ifas.ufl.edu. Follow us on Facebook at http://faceboook.com/bayifas .

An Equal Opportunity Institution. UF/IFAS Extension, University of Florida, Institute of Food and Agricultural Sciences, Nick T. Place, Dean for UF/IFAS Extension. Single copies of UF/IFAS Extension publications (excluding 4-H and youth publications) are available free to Florida residents from county UF/IFAS Extension offices.

This article is also available through the the Panama City New Herald

Prescribed Fire: Habitat Management Tool Number One

Prescribed Fire: Habitat Management Tool Number One

bright yellow flower

Yellow asters such as sneezeweed bloom profusely during summertime in the flatwoods.

Our coastal habitats are some of the most beautiful on the planet. Where else can you have the breathtaking, wide open vistas of our salt marshes, the incredible productivity of our nearshore bays, and the expansive pinelands in the adjacent uplands. Year-round opportunities abound to be outside and enjoy the natural resources we are blessed with. Just go prepared for the inevitable encounter with some of our bloodsucking flies and midges that are part of the package deal. A pair of binoculars, snacks, water and proper clothing provide the makings of a great day out, but I would also recommend a picture-taking device of some sort. I’ve basically given up on the heavier camera gear and the notion of getting long-distance close-ups. I now rely on my cell phone or a small digital camera; mainly for taking photos of flowers, bugs, and anything else that doesn’t require stealth and patience to shoot.

One of the best habitats to explore during this time of year for capturing memorable images is the upland pine flatwoods that is so abundant in the Florida Panhandle. There is no shortage of public lands that display some of the most well-managed pineland landscapes in the nation. Pineland ecosystems in the Southeast have been intimately linked with a natural fire regime, long before Europeans came on the scene. Successional cycles of increasing shrubby growth over time and the ability of the landscape to carry a fire after a lightning strike, have allowed these areas to develop with the “park-like” vista of a pine tree savanna in many cases. When fire is excluded by people, these ecosystems gradually convert to more hardwood species that tend to shade-out herbaceous growth on the ground and reduce the opportunity for new pine seedlings to become established. Professional land managers who work hard to mimic natural fire cycles on the lands they manage produce some astounding results. I can attest, as many of the areas where I hunt turkeys each spring are chosen more for the beauty of the landscape than the abundance of gobblers. Although fewer gobblers is not typically the ideal hunting scenario, the silver lining comes in the form of less competition with other hunters.

This spring I hunted in part of the St. Marks National Wildlife Refuge and had a nice mix of fairly recently burned pinelands to explore. Some were burned this spring, and was just starting to green-up with newly emerging grasses and forbs. Other areas were burned a year or two ago and you would never know it except for the charred bark on tree trunks. These areas recover to full greenery in a very short time. The foot-high wild blueberry bushes were loaded with green berries for summer wildlife feasts to come, and the photo opportunities for wildflowers abounded. Fire is so important in retaining a high species diversity in these habitats. Opening up the canopy allows sunlight to filter through to the forest floor and the recycling of nutrients in the ash supports many unique plants. There are several terrestrial orchids that bloom in the wetter soils (grass pink, colic root, lady’s tresses, etc.), and yellow flowers are prolific right now (St. John’s wort, sneeze weed, candy root and many more). I even saw some parrot pitcher plants in one wet spot, noticeable mainly by their tall maroon flowers. Fetterbush and staggerbush are also blooming with small flowers that look similar to blueberry blooms. The difference in scent of these two Lyonia shrubs is an easy way to tell them apart with fetterbush having a strong musky (not totally unpleasant) smell, while staggerbush (rusty Lyonia) has one of the sweetest, most pleasant smells of spring in the flatwoods.

So, while I did have the opportunity to chase around a gobbler this spring (who easily out-maneuvered me), I truly enjoyed my week of annual leave spent reconnecting with something that we too often take for granted. Take time to locate the state parks, national wildlife refuges, state forests and other public lands in your region. Then go outside. I mean it; none of us should miss the chance of a lifetime to see what we really have here.

white plume of flowers

Crow poison, also know as Osceola’s plume shows up in wet flatwoods, most noticeably after a fire.

Pines of Florida

Pines of Florida

Small pine tree with long needles

Young Longleaf Pine

All of Florida’s ecosystems contain pine trees. There are seven native species in the state; Sand, Slash, Spruce, Shortleaf, Loblolly, Longleaf, and Pond. Each species grows best in its particular environment. Pines are highly important to wildlife habitats as food and shelter. Several species are equally valuable to Florida’s economy. Slash, Loblolly, and Longleaf are cultivated and managed to provide useful products such as paper, industrial chemicals, and lumber. All pines are evergreens, meaning they keep foliage year-round. The leaves emerge from the axil of each scale leaf into long slender needles clustered together in bundles. Needles are produced at the growing tips of each branch and remain on the tree for several years before turning reddish-brown and falling off. The bundles are referred to as “fascicles”. The length and number of needles in each fascicle is one way to help identify the different pine species.

A handy rule of thumb is that pines starting with “S” have needles in twos, while pines starting with “L” have needles in threes. And slash pine, which starts with “SL” has needles in twos and threes. The pond pine is also a three-needled fascicle. Pay attention to their length and the number that are held in a fascicle. Because the numbers per fascicle may vary, be sure to check several fascicles to get an overall sense for the plant! Longleaf has the longest needle, measuring over 10 inches. While sand pine has the shortest needles at around 2 inches in length. Pine cones are also a means for identification. Typically the longer the needle, the bigger the cone. But, they also vary in attachment and “spinyness’.

Pine cone attached to stem of pine tree

Cone of Loblolly Pine, attached directly to the stem

The outer (dorsal) surface of each seed cone scale has a diamond-shaped bulge, or “umbo,” formed by the first year’s growth. The umbo may or may not be armored with a “prickle,” a sharp point but not quite a spine or thorn, at the tip. As the seed cone continues to grow and expand, the exposed area at the end of each scale grows as well. The larger diamond-shaped area around the umbo, formed in the second year of growth, is called the “apophysis.” The shapes of the prickle, umbo, and apophysis can be helpful in identification. The male and female cones are separate structures, but both are present on the same plant. Pollen is produced by male cones and is carried by the wind to female cones where it fertilizes the ovules. Seeds develop and mature inside the female cones (also called the seed cones) for two years, protected by a series of tightly overlapping woody scales. Some pines open their seed cones after two years to release the seeds, while other pines continue to keep their cones tightly closed past maturity and release seeds in response to the heat of a forest fire.

To learn more about Florida’s pines and helpful hint on identification go to:

http://edis.ifas.ufl.edu/pdffiles/fr/fr00300.pdf