Bogs in Northwest Florida
The term bog brings to mind something similar to the term swamp… how is it different? Swamps generally have standing water most of the year; a bog appears dry… until you walk in it and then you then discover that it is wet and mucky. It is a wetland with moist hydric soils that squish beneath you shoes as you walk; actually… many people have ruined their shoes walking through these habitats not realizing just how wet they truly are. With ground saturated the way it is there is little air space in the soil and therefore little oxygen. This lack of oxygen causes a decrease in microbial breakdown so the soil tends to be nutrient poor. The slow breakdown of the leaves releases tannins that cause the soil to become more acidic and thus even less hospitable to life resulting in the accumulation of PEAT.
There are two forms of bog habitat in Escambia County; Seepage Bogs and Shrub Bogs. SEEPAGE BOGS form on slopes of land that are moving from the dry, xeric uplands of such places as longleaf pine forest towards the bottom of the hill where rain run-off collects. Towards the bottom of these slopes the land slow begins to flatten out. The water holding bedrock (AQUIFER) is very close to the surface in some locations and water begins to collect near the surface soil making very wet (HYDRIC) and “Boggy”. The soil in this habitat is generally dry enough for fires to occur so they have a relatively open canopy most of the time. For the 40 known species of plants that live in Seepage Bogs fire is actually required for part of their life cycle. Between the acidic soil and open fire, few shrubby bushes or trees exist here. Because of the standing water and mucky soil, insects of all kinds can be found here in large numbers and this is the haunt of the carnivorous plants.
With the number of wetland and bogs in Florida, carnivorous plant communities are actually not that common. Most are found in an area that includes southern Mississippi, Alabama, Georgia, and the Florida panhandle. Several species are rare and either federally or state listed. Some are only found in this part of the world. In the Florida panhandle 4 species of sundew, 6 species of butterworts, 12 species of bladderworts, and 6 species of pitcher plants can be found. Many varieties can be found in the Apalachicola National Forest, Blackwater State Forest, Yellow River Preserve on the Garcon Peninsula, onboard Eglin Air Force Base, at the Roy Hyatt Environmental Center, and the “Pitcher Plant Prairie” off of Blue Angel Parkway near Tarklin Bayou.
The concept behind carnivorous plants is based on the fact that the soggy, low oxygen, acidic soils hold low concentrations of much needed nutrients in plants. Carnivorous plants evolved to take advantage of the nutrients found in the numerous insects that inhabit the area. Each species has a different mechanism they use to attract and trap their insect prey. Many use coloration, or smell, that appears to be meat – thus attracting flies and other decomposing insects. Some use sweet sugary bait they produce and expose this on bright red filaments to both chemically and visually attract prey. Others are very tiny and are actually below the water level in small pools and puddles that form in these habitats. Here they have trap doors similar to the famous Venus Fly Trap where they circulate water currents in engulf small aquatic insect larva and protozoans; the Venus Fly Trap (Dionaea muscipula) does not live in the Florida Panhandle.
Two of the more commonly seen carnivores are the sundews and the pitcher plants. The Pink Sundew (Drosera capillaries) is easily missed because of its small size; about the size of a quarter or half dollar. They are typically found on the low flat portions of the bogs and are in higher numbers if the canopy is more open. They lie on the ground with their “starfish-like” arms open. At the end of each arm is a pad of filaments each with a drop of sugary nectar as an attractant. When the insect lands on the trap they are first trapped by the molasses like consistency of the sugar solution and then the arm apparatus rolls up entrapping the insect. The plant then releases digestive enzymes and consumes its prey.
The Whitetop Pitcher Plant (Saracenia leucophyllia) can be seen from a distance. The plants grow along the slope and at the flatter-lower portions of the bog. They grow vertically about a foot or two from the ground and produce large red flowers during the breeding season. The tube is filled with rain water and a series of slick-slippery “hairs” along the inside. The insects are first attracted by the coloration of the plant then intrigued to enter the tube because of the sugary solution they release. They tend to slip on the slick hair-like structures and fall into the water. Here they become saturated so they cannot fly and they eventually drown. Like the sundews, they release digestive enzymes into the solution and digest their prey. Pitcher plants cannot be seen all year long. During the colder winter months the “tube” degenerates and the plant survives on the stored food it has been collecting all spring and summer; flowering and growing again the following spring.
There are several members of the bog community that have a symbiotic relationship with the pitcher plants. Many have discovered that these tubes are great attractors for insects and they are insect hunters as well. Several species of spiders are known to crawl into the opening of a pitcher, avoid the hairs, and build a web to trap the insects attracted by the plant. Small frogs have been found sitting near the top collecting bugs as they come by. Some of these slip and become food themselves but many have become quite successful at robbing the pitchers of their prey. Mosquitoes can actually use the watery pool within the plant to raise their larva.
There is one member of this Seepage Bog community that is rare and only found in this area. The Panhandle Lilly (Lillium iridollae) has only been documented in about 20-30 sites in Escambia, Santa Rosa, Okaloosa, and Walton counties; it has also been found in Baldwin and Escambia counties inAlabama.
There are many different kinds of insect eating amphibians and amphibian eating birds and reptiles. Pine Barrens Tree Frog (Hyla andersonii) is listed as a rare species by the Florida Natural Area Inventory but can be found here. Glass lizards are neat animals that appear to be snakes but are in fact lizards. Lizards do not differ from snakes in that they have legs but rather that they possess an external ear opening and eye lids. This animal, the Glass Lizard, has those… so technically it is a lizard. They get the term “glass lizard” from the fact that when handled they, like many species of local lizards, will drop their tail. This is done to confuse predators or let them have it for food; they can regenerate the tail. Ribbon Snakes are common here as are Squirrel Tree Frogs. Like the longleaf pine community, Seepage Bogs require periodic burning to maintain the ecology. Also like the longleaf pine community, because of the suppression of fire by humans many of these plants and animals are listed as either threatened or endangered.
SHRUB BOGS are found at the bottom of the slope. Here the soil is so saturated fire cannot burn so small shrubby woody plants can grow. The pattern of growth here is typically very thick at the margins of the system and a low but thick canopy. If you can cut your way through the vines and dense shrubs you tend to find yourself in an open but dark ecosystem. Here the ground is void of life and basically covered with leaf litter that takes long periods of time to decompose forming thick layers of muck and peat. It is saturated with water, acidic, and anaerobic. Most of the shrubs are small and because of the harsh conditions, diversity is low. The two dominant trees here are the Sweet Bay (Magnolia virginiana) and the Titi (Cyrilla racemiflora). Animals that have been found the Shrub Bog are numerous insects, several types of frogs including the Pine Barrens Frog, snakes – including the Eastern Indigo (Drymarchon corias), a wide variety of woodland birds, shrews, bobcats, and the whitetail deer. The diet of the whitetail deer in these bogs maybe up to 65% Titi leaves.
Whitney, E., D.B. Means, A. Rudloe, (2004), Priceless Florida; natural ecosystems and native species, Pineapple Press,SarasotaFL, pp. 423
Photos: Molly O’Connor – Roy Hyatt Environmental Center
More information: http://edis.ifas.ufl.edu/uw367