Stories of the Swamp

Armchair Interpretive Walks

Friends of Fakahatchee: Dedicated to financial and volunteer support to preserve the unique ecology and cultural heritage of Fakahatchee Strand Preserve State Park and educate the public about its importance.

Hammocks and Cypress Domes

FOF March 9, 2016 Armchair Interpretive Walks

by Tony Marx

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Visitors to Southwest Florida are often intrigued by the undulating tree-covered backdrop which seems to comprise small hills. Most obvious as you drive along I-75 Alligator Alley, this is also evident in the Fakahatchee Strand State Park as you begin driving along the dirt-surfaced Janes Scenic Drive after leaving the paved road. Look to your right at the distant tree line and it is not level as you would expect, when viewed across the open marl prairie. Rather than a rise and fall in elevation, the dome shaped mounds of trees actually indicate a water-filled depression or solution hole under the dome. At its deepest point, the bald cypress trees grow tallest, gaining height and strength from the peat that accumulates at its deepest point. Where the trees grow around the edges of the dome, they grow shorter although they are actually the same age.

These Cypress Heads, or Domes as they are called, remain wet all year round, when the sawgrass prairie and open areas dry up and become parched during the winter and early spring Dry Season. Here alligators and wading birds collect to feed on the surviving aquatic life, and the turkey vultures gather in great numbers to feast on the left-overs. In winter, the cypress trees are bare as they annually shed their needles. These decay and, besides adding to the peat, produce acid which continues to dissolve the limestone base. Thus, the depression very slowly expands over the years.

The sub-tropical South Florida landscape, although seemingly flat, is sensitive to the slight rise and fall of elevation, when a matter of inches can promote a sharp change in scenery. The Fakahatchee Strand Preserve State Park offers an ever changing skyline. Just about all tree and plant communities found in the larger adjoining Big Cypress National Preserve and Everglades  National  Park  are found here. Where the land remains mostly unflooded, pine and palm trees replace the cypress or dense tracts of hardwoods. The ‘tree islands’ seemingly sprouting out of the open stretches of marl prairie as you drive along Tamiami Trail are also found here and one can be seen next to the road on your left about a mile along Janes Scenic Drive.

The opposite to a Cypress Dome, which sometimes looks like a tree island set in a wide expanse of sawgrass prairie, is a Cypress Head, or Hardwood Hammock. It may be a small clump of hardwoods and palms growing on a limestone ridge above the surrounding marshland. Or it may be a wider stretch of jungle vegetation dominated by Gumbo Limbo, Cabbage Palms, Oak, Mahogany, Red Maple, and others which need to remain several feet above the surrounding swamp land. As may be expected, it is home to a variety of animals, birds, and reptiles.At the center it often contains a ‘gator hole’ where alligators gather when the surrounding marsh land dries up in winter. In times of heavy rain – when the surrounding area can flood to a depth of several feet – deer, bear, and Florida panther may also take temporary refuge there.

Seen from the air or on maps, these hammocks have a distinct tear drop shape usually running north to south. They rarely flood and are often surrounded by a moat of water which keeps fires at bay. A profusion of ferns, orchids, and bromeliad adds to the jungle atmosphere. Knowing and recognizing the different tree and plant cover as you drive along Janes Scenic Drive will make your trip all the more rewarding. Deer may be seen on the open prairie, wading birds in shallow water, an owl perched silently watching for an unsuspecting rodent, a raccoon climbing a tree, and always an alligator floating lazily by or resting close to the trail. If you are really lucky, and it’s early morning or close to dusk, you may encounter a black bear or panther crossing the road or appearing ahead on the trail.

Take your time, drive slowly, and stop where safe and clear. Look down at the water, then through and up into the trees, and you will often get a pleasant surprise and a photo opportunity. Whether you see them or not, the Fakahatchee animal, reptile, and bird population is always nearby. Find a spot to park and watch quietly; one of them may appear and venture across the road or be noticed only a few feet away. Of course, a short hike along one of the marked trails is better still. Walk quietly and stop now and again to look and listen. A rustle, call, or movement will direct you to where one of our wildlife friends is going quietly about their business.

Tony Marx is a Florida Master Naturalist and former FOF Board Member. He is also a volunteer interpreter for the Fakahatchee guided tram tours and frequently contributes articles to The Ghost Writer.

Walking on Gators

FOF November 10, 2015 Armchair Interpretive Walks

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by Patrick Higgins

Anyone who sails in the skinny waters of the Ten Thousand Islands, as l regularly do on my catamaran Tropicbird, will occasionally bump the bottom. And so I suppose it’s inevitable that if you stomp around the swamp often enough, you will eventually step on an alligator. I did so for the first time a few weeks ago.

Far from scary it was quite Pythonesque (of the Monty variety). Mike Owen and I were alone deep in the Fak, about 1,000 yards west of East Main surveying some ghost orchids. It was just before the September deluge and water was scarce.

We found ourselves in a broad, shallow depression where there was still 6-8” of water and were focusing on pop-ash trunks about 6 feet above the ground. Mike was ahead as I was determined to make my own discovery, which I didn’t, of course – at least, not of a ghost.

As I put my foot down, a gator whipped around in a lightning splash and grasped onto it. Now, you have to look at this from the poor gator’s perspective. It had nowhere to go as there wasn’t water elsewhere; so it probably had elevated down as I approached, pressing itself hard against the bottom to gain a few inches of cover. It can’t be pleasant to have 240 pounds step on your back. Its reaction was purely defensive.

Luckily I was already raising my foot as its teeth fastened onto my boot, so it had a grip on the sides on my sole rather than the top of my foot where I would have felt the bite force. Also, it was only a five-footer.

So there we were; the gator’s teeth stuck momentarily in the rubber sides of my boot’s sole and me hopping backwards on one leg dragging the creature with me whilst trying to keep my balance with my stick – all the while trying to shake the darn thing off and shouting, “Mike, I got a five foot gator on my foot!” This impasse lasted only a few seconds. I think the gator was as keen to let go as I was for him to do so and maybe even had his teeth stuck.

Mike almost stepped on a cottonmouth coiled on a dry patch during the distraction but was most solicitous, insisting if there was any skin broken I go to the hospital because of the risk of infection. But the only injuries were my pride and a few small perforations in my boot sole. I did get some kudos, though, because scientist to the end, even in my excitement, I hadn’t exaggerated the gator’s length. When we approached him afterwards sure enough he was five feet, and with nowhere to hide, he rotated around to face us and scowled.

I suppose seeing the humor of the moment even as it happened comes from a long, albeit sporadic, association with reptiles. Growing up my father wouldn’t allow us to keep any pets that could harbor fleas, and so by eleven years old I had a caiman living in my bath tub and a collection of snakes and lizards.

I should mention for the benefit of those whom I lead on swamp walks, that it was entirely my own fault and that when I lead the public groups I always pre-reconnoiter the route so I can concentrate on their safety and enjoyment. In any case, our swamp walks are during the cooler months when gators are less active or inactive. As I often tell my parties: they normally avoid humans, don’t feed when the water temperature is below 70°, and like all predators are very cautious about injury so won’t tackle prey bigger than themselves. And even if you’re not six foot one like me, when you’re in a group you seem like a big organism.

I’ve never actually encountered an alligator on a public swamp walk in the water. If we see one it’s usually on the tram and by that, in case I’m alarming any potential tram tour participants, I mean on the old logging trails which in the Fakahatchee we have come to call trams, not on the tour vehicle! But just knowing they are out there, along with black bears and panthers, adds to the enjoyment of being in one of Florida’s last remaining wilderness areas.

Patrick Higgins is a National Association of Interpretation Certified Interpreter, Vice-President of the Friends of Fakahatchee and Project Manager for the development of the Boardwalk Master Interpretive Plan.

One man’s fruit; another man’s poison

FOF September 3, 2015 Armchair Interpretive Walks

by Patrick Higgins

After spending July in England I was ready for a Fakahatchee fix. So still jet-lagged I headed to the swamp, stopping first at Big Cypress Bend Boardwalk to see how our new signs were faring. Donning my Fakahatchee cap and in a matching shirt, I was an obvious target as I stepped out of my SUV and was quickly waylaid by a charming French couple and their ten year old daughter. They asked if the Indian Village was worth visiting. Hmm – a common misconception that our new entrance will address.

They had pulled over to picnic and complained they had just been on an airboat tour and not seen a single gator. They quoted their guide, “with so little water gators are hard to find.” This was August. When I left the rainy season was in full swing. What was up?

I ended up giving our French guests an extended tour, but sure enough there wasn’t any water until the gator hole, except for the small pond in the root hollow created by a toppled tree. Nevertheless they were delighted. I was able to point out a well camouflaged 6 ft female alligator with half a dozen hatchlings in the borrow ditch. The hatchlings were the smallest I’d ever seen and couldn’t have been more than a day old. After that a barred owl obligingly flew in and roosted not 10 ft from us and a six lined skink let us get close–up and personal. Their day was made. The new signs were holding up well by the way.

My next stop was to check out Six-pipe slough on Janes Scenic Drive. Instead of water gushing through the culvert, there was barely as much water as we had for our winter swamp walks. If rain didn’t come to the Fakahatchee soon, and lots of it, the season ahead looked tough. It was then that I spied the marbled-green fruit of a pond, aka custard apple.

Pond apples, (Annona glabra) with their cherry-like bark, big glossy leaves and buttressed trunks are one of my favorite trees. They bear the largest fruit of any of our natives and its light wood was used by Calusa and later Native Americans to make fishing floats. The pond apple also happens to be the larval food of the giant sphinx moth; the pollinator of the ghost orchid. Although the vast majority of our ghosts are found on pop ash trees, about 15% utilise pond apples.

Ripe pond apple

Ripe pond apple fruit has poisonous seeds, mild yellow flesh, and is an important wildlife food. Although sometimes called alligator apple, it’s more commonly consumed by turtles, birds, raccoons and squirrels.

. The creamy yellow flower of the pond apple with petals and sepals in 3s

The creamy yellow flower of the pond apple with petals and sepals in 3s.

I collected a fallen fruit and sliced a wedge out with my knife, being careful to avoid the poisonous seeds and took a bite. Not quite ripe – the flesh hadn’t yet turned yellow. Perhaps a passing vehicle had detached this one prematurely. Its taste was not unpleasant, although a bit insipid with just a hint of passion fruit. But it’s an important wildlife food, hence one of its other aliases alligator apple, although more commonly it’s consumed by turtles, birds, raccoons and squirrels.

Pond apple trees were once much more common in Florida. Patrick D. Smith, in his A Land Remembered, paints a portrait of a vast bygone pond apple forest that grew along the southern shores of Lake Okeechobee, swarming with moon vine, airplants and Carolina parakeets that has since been destroyed by drainage dikes to make way for sugarcane and other agriculture.

Like most of our tropicals, the pond apple is at the northernmost limit of its range. They naturally occur on both sides of the Atlantic aided by their buoyant fruit and range from South Florida through the West Indies, to South American and West Africa.

Due to its hardiness and tolerance of brackish conditions A. glabra has been used as a rootstock to graft some of its more desirable cousins, such as soursop (A. muricata) and sugar apple (A. squamosa). What’s one man fruit is another man’s poison. In Australia escapees from this process have become highly invasive, especially in the wet tropics of northern Queensland where ironically, or maybe in a case of poetic justice, the invasive pond apple threatens their melaleuca wetlands, as well as some native mangrove communities.

The Friends of Fakahatchee’s Captain Franklins Adams remembers a large pond apple swamp along Janes Scenic Drive in the late 1950’s and early 60’s when the Fakahatchee was still a State of Florida Wildlife Management Area run by the old Game & Freshwater Fish Commission.
Franklin says, “My family and friends would camp and sometimes hunt the area for turkeys or buck deer. Janes Scenic Drive had not been designated and the old main logging road was then referred to locally as the Copeland Grade.”

“The pond apple swamp location as I recall was near the west end of the Copeland Grade primarily on the south side of the tram. In the evening wood ducks would fly into the pond apple swamp to roost for the night. We sometimes camped in the wide spot on the south side of the grade where today there are some sour orange trees, the Fakahatchee sign and a water gauge location. On the opposite side are the old rock borrow pits.”

“1961 was a drought year and may have been the year that fire was able to enter the pond apple swamp and burn the muck down to the limestone foundation. Nothing remained of this beautiful area and subsequent wet seasons filled the limestone cavities with detritus.”

Franklin has been back a number of times to try and find the pond apple swamp’s remains but there’s no trace of it. For now we’ll have to be content with a scattering of trees along our trams and Janes Scenic Drive and the population deep in the swamp.

The Fakahatchee Wetlands

FOF April 8, 2015 Armchair Interpretive Walks

by Anthony (Tony) Marx

Photo taken by the author off Janes Scenic Drive.

Photo taken by the author off Janes Scenic Drive.

The Fakahatchee Ecosystem is unique. Although part of the United States mainland, it contains plants that exist only within its borders (or very close by); others are found in the Caribbean, Central and South America. Many elements contribute to this delicate and fragile wilderness, each dependent on the other. Its preservation has enabled us to experience what much of South Florida looked like prior to the twentieth century.

South Florida has a sub-tropical climate, but the Fakahatchee Strand Preserve State Park itself actually enjoys a tropical climate within its depths. Thus, a mild temperature exists year round, slightly warmer in winter and slightly cooler in summer, perfect for the rare ferns, bromeliads and orchids that exist year round. Some are visible from the Boardwalk and on the hiking trails, while others only reward those who venture into the interior swamps off the trail, usually by joining a ranger-led swamp walk.

Much of the Fakahatchee is natural wetland, meaning it existed  before  man  began altering its topography, but it includes uplands and aquatic systems, too. Seen from the air it presents a mosaic of contrasting colors. It includes sweeps of dun-colored upland prairie studded with contrasting green hammocks of tropical hardwood and clumps of pineland rooted on higher ground. The interior is a dark green forested swamp studded with stands of tall Royal Palms poking above the canopy. These are matched only by the occasional Bald Cypress which escaped the loggers attention sixty to a hundred years ago.

The ground slopes gently south, 2” to 4” per mile, quickly becoming wetter, with a central linear strand slough (wide, straight, shallow moving river) fed from two directions. Water enters the park from the north and flows south to disperse in the marshes south of US-41, and finally into the coastal mangroves. The depth ranges up to 6’ in summer, leaving a series of ponds that remain during the dry winter months. Theses provide the humidity needed for vegetation and a water source for the park’s wildlife. South of US-41, the wetlands consist of mostly open, saw grass prairie, with patches of marsh and swamp and shallow water courses navigable by kayak. Finally, mangroves herald the transition from brackish to saline, signaling proximity to the Gulf and home to the endangered American crocodile.

Although the Fakahatchee recovered from its period of logging from 1913 and reaching maximum output in the 1940s and 1950s, it is also partly an ‘Altered Ecosystem’. It is somewhat impacted by run-off from agricultural and ranchland to the north, its crucial water supply sources being the Okaloacoochee State Forest near Immokalee and the Caloosahatchee basin to the north-west. In both cases, before reaching the Park, the water flow competes with the needs of agricultural businesses and now the expanding development of Ave Maria and the  huge planned city of Big Cypress stretching east from North Naples to Immokalee. Thankfully, during its progress through the Park, these pollutants are captured and absorbed by wetland plants, helping protect the crucially important spawning areas without which commercial and recreational fishing cannot survive.

The hiking trails and road access are all located in the northern half, starting at the Copeland ranger station, using the beds that were formerly logging rail tracks known as ‘trams’. The interior of the park is bisected by the dirt-surfaced Janes Scenic Drive, with hiking trails leading off it, elevated on what were originally the beds of trams hauling lumber out of the interior. These are the West and East Main, Mud Tram, and Uplands Trails. For those preferring a less strenuous introduction to the Park, the Boardwalk on US-41, located 7 miles west of the Everglades City Junction, offers enchanting views of the tropical forest and its wildlife, accompanied by newly-designed interpretive signs along its length.

The never-ending battle of conservationists versus developers will continue. The good news is that nearly 70% of Collier County is preserved under the jurisdiction of local, state, federal, and private management. More is being added on a regular basis, either by county and state government acquisition or private bequest. This is how the Fakahatchee State Park has expanded since 1974, when only a third of its present size at the outset.

At 85,000 acres it is the largest of Florida’s State Parks and is surrounded by protected and preserved land managed by other authorities. It is bounded on the north by the Florida Panther Preserve, and the Picayune State Forest adjoins its western side. The vast Big Cypress National Preserve is on its eastern side across State Road 29, and the Everglades National Park Ten Thousand Islands section is on its south-eastern corner.

Tony Marx is a Florida Master Naturalist and FOF Board Member. He is also a volunteer interpreter for the Fakahatchee guided tram tours and frequently contributes articles to The Ghost Writer.

Fire, a Natural Part of our Ecosystem

FOF February 26, 2015 Armchair Interpretive Walks

By Patrick Higgins

I just happened to be leading a combined tram tour and swamp walk on the 29th of January when the Park’s Burn Specialist, Steve Houseknecht, and his team were setting Lee-Cypress Prairie ablaze. It was of course a prescribed burn, in this case of some 400 acres from the road to the margins of the swamp beyond.

Trundling down Janes Scenic Drive on the Ghost-rider, our passengers had a front row view of the burn crew, decked out in their helmets and yellow Nomex jackets, igniting the dry grasses and shrubs with their drip-torches. We traversed a smouldering landscape with flames lapping at hammocks in the distance. Hawks moved from perch to perch just ahead of the fire head watching for fleeing prey or perhaps some fresh barbeque. Later, wading in Six Pipe Slough we had the novel experience of snow in the Fakahatchee, as white ash rained down upon us.

South Florida is the lightning capital of the USA with an average of 25 lightning strikes per square mile and more thunderstorm days than anywhere else in the country. This, coupled with seasonal drying, makes wildfire a natural component of our environment. As a consequence most of our ecosystems have evolved to be fire dependent.

The majority of lightning strikes are between June and September, coinciding with the peak of our wet season, so the resulting fires tend to be lighter in touch and more localized. However wildfires from thunderstorms in late spring, when there’s lots of accumulated dry fuel about, tend to be wider sweeping, more severe, and can even alter the soil structure. But with the creation of roads and  canals that act as firebreaks and fragmentation of the habitat, this cycle cannot take its natural course. So we have prescribed burns that attempt to mimic this otherwise natural phenomenon. The Fakahatchee has the largest prescribed burn program in Florida’s State Park system.

Fire maintains the habitat by preventing succession. Without fire, shrubs and trees would invade our marshes and wet prairies, eventually drying them out. Fire releases and recycles nutrients locked up in plant tissue, keeps non-fire adapted invasive plants in check, and alters the landscape spatially, creating clearings and opportunity for burnt areas to experience increases in native wildflowers, birds and other wildlife. In the case of prescribed burns, they also protect Park neighbors and facilities by reducing potential fuel for wildfires.

New growth abounds n Lee Cypress Prairie just two weeks after a prescribed burn. Photo by Patrick Higgins.

New growth abounds in Lee Cypress Prairie just two weeks after a prescribed burn. Photo by Patrick Higgins.

I tramped across the charred landscape 2 weeks later and was greeted by fresh sweet green shoots of grass already 6 inches high being grazed upon by white-tailed deer. More remarkable were the thistles in flower everywhere, poised to create seeds to colonize new terrain. The burn also revealed some of the prairie’s normally hidden structure like the recumbent trunks of saw palmettos, cap rock, or circles of cypress knees around old logged stumps, as well as a littering of white shells from the previous seasons’ apple snails.

Of particular interest to me was how the prairie hammocks had faired. Many of the smaller islands of cabbage palm and saw palmetto appeared incinerated, although I knew within a few weeks the palmetto’s blackened trunks would be sprouting new fronds. The hardwood hammocks however were largely untouched. Some are protected by shallow perimeter moats, but it’s the deep shade of their interiors that create microclimates with higher humidity that seems to keep them safe. In most cases it was just the volatile wax myrtle around their margins that had burned.

There’s no water in most of the borrow ditch paralleling lower Janes Scenic Drive right now, so the burnt prairie is easy to access. Try investigating it on foot before the grasses gets too high again and compare it with unburnt Copeland Prairie to the east. Personally I’m waiting for autumn when the muhly grass ought to be spectacular. It flowers best after a good burn.

Restoring the Giant Air Plant

FOF January 6, 2015 Armchair Interpretive Walks

by Mike Owen and Karen Relish

The Friends of Fakahatchee are an important part of a team to rescue bromeliads, especially the Tillandsia utriculata or Giant Air Plants, seemingly a favorite of the non-native Metamasius callizona or Mexican Bromeliad Weevil. Typically, after about 10 to 15 years of growth, the Giant Air Plant sends up a seed stalk or spike up to 6 feet long, produces flowers in June, then produces thousands of seeds during spring, and then dies unlike many of the other Florida bromeliads which can also reproduce vegetatively by pupping.

Chad Washurn of Naples Botanical Garden, Fakahatchee biologist Mike Owen, and Bruce Holst of Selby Botanical Garden with the Giant Air Plants.

Chad Washurn of Naples Botanical Garden, Fakahatchee biologist Mike Owen, and Bruce Holst of Selby Botanical Garden with the Giant Air Plants.

The Friends of Fakahatchee contributions will assist other team members at Naples Botanical Gardens, Selby Botanical Gardens and possible affiliates to educate, quarantine/monitor, then regularly treat with an insecticide the recovered plants as well as provide materials to re-attach to hosts, and logistical support for the Giant Air Plants from Fakahatchee Strand Preserve State Park and from its headwaters Okaloacoochee Slough State Wildlife Management Area and other Florida Natural Areas.

Work on the Giant Air Plant and other bromeliads at Fakahatchee and other parks around the state was initiated at University of Florida by Teresa Cooper for her graduate work. She is currently working for Indian River Research and Education  Center in Fort Pierce with Ron Cave. From December 2008 through December 2013, Mike Owen and primarily two Fakahatchee volunteers continued and expanded the monitoring within the center of the Fakahatchee Strand along 7 miles of Janes Scenic Drive. With the dedicated efforts of the two volunteers, including one who entered the data and created the graphs, the monitoring efforts produced an annual snapshot of the Mexican bromeliad weevil invasion that reached the sampling area in 2010. The December 2013 data revealed an over-80% decline of the Giant Air Plants, especially  north  to  south  along  Janes  Scenic  Drive.  Upon seeing this in graph form, Mike Owen obtained the necessary permission and permits to collect some of the known remaining surveyed  plants, approximately 160 of them, to place under the conservation efforts of the Gardens’ staff and volunteers to enable a healthy seed stalk and seed production.

On November 13, 2014, 16 Giant Air Plants were ready to be returned to the Fakahatchee. Using the data gathered, they were returned to as close to the same tree, height, and distance from Janes Scenic Drive that they originated. Team members from both Gardens, including interns from Belize, and Fakahatchee staff and volunteers assisted in this process. By the time these seeds mature into plants, we are hoping with the tireless team efforts that we will see them produce healthy seed stalks and successfully release thousands of seeds back to the Fakahatchee Strand. Each year in November the plants, safely protected from the ravages of the weevil larvae at the two  Botanical  Gardens,  that  produced  a  spike  during  the previous June will be returned to the Fakahatchee Strand to continue the release of seeds into the swamp.

Flying Rodents They’re Not

FOF November 4, 2014 Armchair Interpretive Walks

by Patrick Higgins

It was dark. Glen Stacell and I were rolling slowly down Janes Scenic Drive with lights dimmed in his pick-up truck. There was just the soft crunch of tires on gravel. The silhouettes of cabbage palms and cypress contrasted against the evening sky.  Each of us had an arm out a side window holding a small black device aloft listening for clicks.  We were reconnoitering our upcoming new moonlit tram tours and searching for some of Fakahatchee’s bats.

Eastern pipistrelle, Fakahatchee's smallest bat. Photo by Dr. J. Scott Altenbach

Eastern pipistrelle, Fakahatchee’s smallest bat. Photo by Dr. J. Scott Altenbach

Eight of Florida’s 13 species of bat frequent the Fakahatchee; the Seminole bat (Lasiurus seminolus), Big brown bat  (Eptesicus fuscus), Brazilian free-tailed bat (Tadarida brasiliensis), Evening bat (Nycticeius humeralis), Eastern pipistrelle or Tricolored bat (Pipistrellus subflavus), Northern yellow bat (Lasiurus intermedius), Rafinesque’s big-eared bat (Corynorhinus rafinesquii)  and the endangered Florida bonneted bat (Eumops floridanus).

The Seminole bat, Northern yellow and pipistrelle are solitary roosters utilizing clumps of Spanish moss, dried palm fronds and old tree cavities.  The others are colonial roosters. The Brazilian free-tail and Big-eared have now adapted to man-made structures.  The Brazilian likes bridges and picnic shelters, and is particularly partial to the crevices under barrel tile roofs, a penchant shared with bonneted bats. The Big-eared strays less far from its preferred forest habitat and is more likely to use old cabins and sheds. The evening bat is less picky and sometimes found in the folds of patio umbrellas.  All are slow reproducers with typically a single pup born each spring.

Like all bats they are the subjects of many misconceptions, even being referred to as flying rodents. Bats are in fact in an order all of their own, Chiroptera, from the Greek aptly meaning hand-wing, and may be closer related to primates than rodents.

They are a diverse group accounting for almost 20% of all known mammal species and can be divided into two suborders; the megabats or flying foxes of the old-world tropics, sometimes referred to as fruit bats, and the ubiquitous microbats which include all of Florida’s species.

Our bats are small; ranging from our smallest, the Eastern pipistrelle with a 9” wingspan but weighing in at a mere ¼ oz, to our largest, the Florida bonneted bat with a 20” wingspan but, still only about 1 ¼ oz weight. Despite their diminutive body mass bats are extraordinarily long-lived. Some bats weighing less than an ounce have lifespans of 30 years.

Flying foxes in particular put paid to the myth ‘as blind as a bat’. They have excellent binocular 3D color vision.  But even the smaller eyes of our microbats have highly refractive lens and are densely packed with rods. They have good night vision, but nobody goes around saying, “as sharp as a bat’s eyes at night.”  Microbat eyesight is however made largely redundant by their ability to echolocate: to use reflected sound waves to map their environment in the same manner as dolphins.  This remarkable sixth sense allows them to determine distance, size, shape, texture, speed and direction.

Not only are bats not the harbingers of evil portrayed in horror films, they are highly beneficial, providing many important ecosystem services. Not least of these in Florida is that our species are all insectivorous typically consuming their own body weight in insects every night.  Depending on the size of the bat and size of the insect this can total several thousand ‘bugs’, many of which may be agricultural pests.  In other parts of the world they provide pollination services as well.

As Glen and I proceeded, our scanners periodically rippled to life, with the distinctive slower pulses of bats in the search mode, followed by increasingly frantic chirps as they closed on their targets, culminating in a feeding buzz which ends abruptly when the insect is scooped by wing or tail membrane into its mouth.  Occasionally we also picked up insect noise when it intruded into the bats’ frequency range, but this was a like a low muffled roar and easily distinguishable.

We think of nocturnal predators as being quiet, but bats are noisy, broadcasting at 110-120 decibels, which is the same level as standing next to a jackhammer. So it’s a good thing that most of their calls are ultrasonic and well above 20 kHz, the upper limit of human hearing.  It makes perfect sense being so loud if you’re trying to resolve a moving object as small as a mosquito.

Our Swiss bat detectors are only the size of cigarette packs but quite sophisticated, as well as quite expensive, although I won’t say quite how much in case my wife reads this.  They automatically scan the full chiropteran echolocation frequency range, which varies by species. They then transform the chirp into our audible range, modulate its volume, and display its frequency. This provides a clue to identification, but only a clue as the call ranges of many bats overlap.  However, armed with this and the knowledge of what bats are likely to be found in any given area, one can make a pretty good guess.  Even more sophisticated bat scanners can record wave patterns that can be downloaded onto a computer for analysis and positive identification.

But this aerial combat is not all one sided.  Many insects can detect the bats signals and take evasive actions or apply countermeasures.  Some moths will fold their wings and suddenly drop to the ground. Tiger moths take a different tack. Their larvae feed on toxic plants that make them taste nasty so they emit a series of clicks to warn off an approaching bat.

Earlier in the day Glen had a sugared a few trees along our route with a homemade concoction of rum, molasses and brown sugar.  I would rather have drunk it, but he painted it on several trunks in the hope of attracting moths. The idea was to see what the bats might be feeding on.  It worked well up north, but we didn’t have any luck with it that night, so will revert to the time-honored tradition of a white sheet and backlight for our tours. We had better success with the fireflies and were able to attract a few towards us using a keychain LED flashlight, but you have to get the flash pattern just right for the particular species.  We look forward to sharing our new skills with our moonlight tram riders and boardwalk-after-dark strollers.

Night Ramblings

FOF September 18, 2014 Armchair Interpretive Walks

Night Ramblings
by Patrick Higgins

 View of South Oxfordshire from atop the Chilterns at Watlington Hill. Photo by Patrick Higgins

View of South Oxfordshire from atop the Chilterns at Watlington Hill. Photo by Patrick Higgins

Late July found me stumbling down a sunken way with Martha in the pitch dark of a moonless night. Our rough path was hemmed in by ancient yew and beech trees. We were in the Chiltern Hills of South Oxfordshire – an area designated as being of Outstanding Natural Beauty, a Site of Special Scientific Interest and a Special Area of Conservation about 15 minutes from our son’s house in Watlington where we were staying.  The broad bottomed ditch we were negotiating dated back to Saxon times.  In the darkness with the clinking of key chains and water bottles one could almost hear “the tramp of Saxon foemen, Saxon spearmen, Saxon bowmen” although more commonly this path would have been trampled by generations of Saxon farmers taking their animals to market; merchants with their wares travelling between settlements and woodsmen hauling timber and charcoal.

Further down, the sunken way was bisected by an old Roman road, now resurfaced and travelled by cars. For some unknown reason the Roman routes are always straighter than most of our modern English highways. Behind me, back up the hill, our ditch led to the Ridgeway, Britain’s oldest byway dating back over 5,000 years, which stretched from the Norfolk coast to that of Dorset, linking up Neolithic sites like Stonehenge and Avebury.  It’s hard to escape history in England, but we were in search of the glow worm (Lampyris noctiluca), cousins to Fakahatchee’s fireflies in Aston Rowant National Nature Reserve.  However, in the dark my mind kept wandering to the Fakahatchee because I had to give a talk locally on the Everglades Ecosystem and was also planning some new night-time interpretive programs for the upcoming season back in Florida.

The Reserve is a mosaic of chalk grassland, beech woodland and Juniper scrub sitting atop 300 feet of chalk, formed 350 million years ago from the compressed calcite shells of microscopic Foraminifera that lived in the warm, shallow seas that once covered southern Britain.  Chalk grassland is a unique and fragile habitat, important for both its beauty and wildlife value. It is the product of centuries of grazing by animals on nutrient poor chalk soils and is characterized by a short turf rich in herbs, flowers, butterflies and grasses, and like the Fakahatchee also in orchids, although here they are all terrestrial.

Comparisons between the ecosystems continued to flood my thoughts as we bumped along. In one we employ prescribed burns to maintain the habitat. Here, it’s the grazing of a large flock of speckle-faced sheep and a few Dartmoor ponies that controls the spread of young scrub and keeps chalk grassland healthy.

Aston Rowant, at only some the 500 acres, is a classic example of the threat to biodiversity through islandization and habitat fragmentation. Especially as even this small, precious parcel is sliced into two by a massive cut for the six lane M40 motorway from London to Oxford which paralleled our route just over the rise. It was further affirmation why the Fakahatchee is important; not just because of its unique plant communities, but also as Florida’s largest State Park because of its scale. When it comes to maintaining biodiversity, size does matter!

Back in Florida swallow-tailed kites would just be beginning to assemble for their annual 4,500 mile return migration to South America. Here there were Red kites (Milvus milvus).  They had been reduced to just a handful of pairs in Wales through past persecution. It was mistakenly believed that they were a threat to gamebirds and livestock, but recently they have made a remarkable comeback. Through a reintroduction program using chicks taken from northern Spain there are now some 250 breeding pairs in the Chilterns.   With a 5 ½ foot wingspan Red kites are a much larger bird than our swallow-tail, weighing 2 – 3 pounds versus 10–20 ounces and their ecological role is different too. Rather than being canopy feeders they are primarily carrion feeders, filling the role of vultures, although they will take small mammals too if caught in the open. The locals who once persecuted them now throw the bones from their Sunday joints out on to the lawn to watch them swoop in, a practice sadly that does not encourage the kites’ dispersal into new territory.

Field of yellow meadow ant mounds. Photo by Phil Champion

Field of yellow meadow ant mounds. Photo by Phil Champion

In Florida the instant we step off the road we are on the alert for fire ant nests.  Here there is an unseen benevolent ant, the Yellow meadow ant (Lasius flavus). The chalk grassland and other undisturbed ancient pasture areas are dotted with myriads of small grassy domes that look almost like neatly planted helmets. These are actually ant-hills, some over a hundred years old. Inside of each is a colony of up to 5,000 meadow ants that feed the by farming the sap sucking aphids that live on the roots of the surrounding forbs and grasses.  The ants milk the greenfly for honeydew which they carry back to their colony and in the winter will eat the aphids themselves. Their subterranean activities control damaging insects, open up the soil keeping it porous and their droppings fertilize the grasses’ roots. They also have a curious relationship with the Chalkhill blue butterfly (Polyommatus coridon). Attracted by secretions they will bury the pupa, unintentionally protecting it from predators.

Wingless female glow worm (Lampyris noctiluca). Photo by Barry Crowley

Wingless female glow worm (Lampyris noctiluca). Photo by Barry Crowley

After about 45 minutes bumbling about we finally detected the steady green glow of our target, a glow worm.  It was about a foot off the track, naturally in completely the wrong spot deep in the woodland.  Glow worms of course are not a worms at all but a bioluminescent beetle just like our related firefly.  In their larval stage they are predatory and hunt snails, which why calciferous habitats that favour snails like chalk grasslands are preferred. As adults they rarely feed.
In the glow worm’s case it is only the inch long wingless female that glows significantly.  She had climbed up a dried grass stem about 12 inches above the ground then curled her abdomen slightly upward to display the last few segments of her abdomen where her glowing organs are located in hope of attracting a passing male.  Unlike American fireflies she can’t readily turn her glow on and off – it’s rather like a very slow starting fluorescent tube, which takes about 20 minutes to cycle so they don’t flash.  Misplaced deep in the woods she would be very lucky to have any success.  As well as attracting a mate, the glowing abdomen is a warning to predators to stay away – bioluminescent chemicals taste bad.

Nevertheless, hers is a very efficient light source. Unlike incandescent light bulbs that only, transform about 3% of the energy used into light, bioluminescence is generally 90 to 98% efficient.  The light is produced by a reaction between calcium, luciferin and ATP in the presence of the catalyst luciferase and oxygen, using nitric oxide as a chemical on/off oxygen valve. It is the switching on and off of the oxygen flow which allows American fireflies to flash.  Specific flash patterns are used to identify other members of their species, as well as members of the opposite sex and even. In the case of some Photuris fireflies, it is to mimic the light signals of other firefly species to lure, kill, and eat them.  Studies of America’s most common Photinus species show that females are more attracted to males that flash longer and faster. A flash can bring either sex or death!  We shall be trying a bit of mimicry ourselves on our moonlight tram rides down Jane’s Scenic Drive this season to see if we can attract any eager males.  It’s just a case of getting the response timing right.

Anyways, that solitary glow worm by the trail was the only one we saw that night.  We scoured the open grassland to no avail.  I guess we missed the peak by about a week, but even then observers were only seeing a dozen specimens a night on this site. Light pollution as well as habitat loss is taking a toll on these interesting insects.  We’re pretty lucky in the Fakahatchee.

What is a Snag?

FOF May 27, 2014 Armchair Interpretive Walks

by Sam Peters

snagbypetermcclure4webThere is some debate about what constitutes a Snag, Is it a dead tree? Is it on the ground? Is it in the water? Is it a loose thread? The Urban Dictionary defines snags as a “sensitive new age guy.” So, there are many definitions … For our purposes, a Snag is a standing dead or dying tree.

A Downed Tree is a log lying on or near a forest floor; however, a downed tree in a body of water is called a snag in certain areas of the South and Midwest. In Alaskan rivers it can be called a preacher. Other areas it is called a sawyer. Both sawyer and preacher derive from the tree or log rising and falling and bowing in a current of a river.

To some people, Snags are ugly and should be removed from a forest. After all, they are not classic, formal beauty; they’re dead. However, trees are the gift that keeps on giving. As they grow, they provide habitat and shelter for many different species; when they die, they still provide shelter and habitat, but now for different animals. Depending on the species of tree, it can last for as long as 70 years. They start out as Hard Snags, which means that they still have the bark and their cambium layer; as they lose their bark and decay further, they become Soft Snags. This is when the most animals begin to move in.

Some of the birds which use Snags are woodpeckers, wrens, barred owl, vultures and hawks. Also many insects, reptiles and amphibians call a dead tree home.

As the tree ages, different animals make use of it. For instance, woodpeckers will make use of an area of a snag and when the woodpeckers move on, other birds will enlarge the holes and move in. As they move on, more birds or other animals will make use of the cavity. This can go on until the cavity becomes large enough to house a squirrel, or a raccoon nest.

Some fungi, moss, and lichen live their entire lives on dead trees. Bacteria live in decaying wood, creating fertilizer which will mix with the soil when the tree falls. Shelf mushrooms make use of Snags and Downed Trees. Snags provide food and habitat for almost 1/3 of our wildlife. Over forty different types of birds use Snags at one time or another.

Snags should be protected and left standing for reasons of habitat and forest health. They are used for foraging, nesting, perching, hunting and roosting.

We need Snags to be maintained in a variety of sizes, shapes and ages. A group of larger Snags is more valuable as it provides habitat for a greater variety of species. Small clumps of snags will provide nesting and foraging sites. Snags should exist in various stages of decay, as they support different plants and animals at different stages of their existence. So, different stages for diverse species and different sizes and shapes for the same reason.

A single large Snag is rarely used by more than one pair of the same species.

Forest management now includes Snags. This would include not cutting down dead trees and culling trees in a crowded area, but leaving them standing and creating new Snags. Fire may also be used as fire can both create new Snags and destroy old ones.

What can we do? Depending on where we live, we can maintain Snags and/or create new ones. Please don’t use fire in your neighborhood. However, if a tree dies, leave it alone if it is not a danger to anything or cut it to a size where it will not hurt anything if it falls. You may also kill an unwanted tree yet leave it standing. Some of the ways to kill it would be to gird the tree, top and trim it and of course poison always works. Girding does weaken the tree and if done will rot the tree from the outside in. This will cause the tree to rot and fall much more quickly than when it dies and rots from the inside out, which is the natural way.

The Fakahatchee has many Snags in various states of decay. They occur naturally and are of great service to the forest community. If you look closely, you can see that the Snag is occupied by many animals and if you look twice you may even come to believe that they are beautiful in their own natural way.

Sam Peters is an FOF member from Miami Beach.

The Wetland Neighbors

FOF May 27, 2014 Armchair Interpretive Walks

by Anthony (Tony) Marx

Aerial  photo   of  the  “south blocks”  in the  Picayune by Marya Repko taken several years ago.

Aerial photo of the “south blocks” in the Picayune by Marya Repko taken several years ago.

Once considered as useless and a noxious, snake and insect infested source of fevers which must be drained and developed, half of the wetlands that existed at Florida Statehood have been destroyed. However Collier County is blessed with over 72% of its land acreage designated as conservation land – more than twice that of neighboring counties.

There is a stark difference between the 85,000-acre Fakahatchee State Preserve and the adjoining Picayune State Forest, which at 78,000 acres is almost as large. The Fakahatchee is a vibrant, natural world pulsating with life and home to a huge variety of rare plant life and endangered animals; whereas the Picayune, once also a similar wetland, was logged, cleared and partially developed, then abandoned. This transformed it into a dry landscape with upland trees and vegetation. Non-native vegetation including Brazilian Pepper, always present when land is disturbed, also moved in. Over two hundred miles of elevated roads acted as levies to further stop natural water flow between the canals. The difference is most noticeable when you access the Picayune State Forest through its back entrance at the end of Janes Scenic Drive in the Fakahatchee State Park. Outdated maps show a grid of streets which are mostly non-existent. The massive Comprehensive Everglades Restoration Plan (CERP) is changing the landscape in every respect. The bridge, on entering over the former Prairie has gone and the canal plugged, so it is now a series of small ponds.

Photo of equipment filling in a canal by Dennis Giardina.

Photo of equipment filling in a canal by Dennis Giardina.

Heading west, the partial dirt and paved road still shown on maps as Stewart has been leveled flat with the surrounding landscape, and on either side large swathes of scrub have been bulldozed clear of all vegetation and leveled to start sheet water flowing. Progress is occasionally blocked at the next canal bridge, but if you can proceed you’ll find that the formerly paved Everglades Boulevard section leading to Naples has also had its surface removed and the last time I was there it was gated closed. Heavy equipment is seen working here and there, bulldozing and trucking away debris. Close to I-75 instead of water flowing south down canals to the estuaries, the new and powerful pumping stations under construction will send water flowing fanlike south through spreader channels in an east-west direction while the remaining three canals running north to south will be plugged to varying degrees.

Boulevard in the Picayune taken by Tony Marx in 2011.

Boulevard in the Picayune taken by Tony Marx in 2011.

If you plan to try and reach Naples from the Picayune be prepared to turn back, as the road may be blocked by either a closed gate or sheet water in summer. In time it will return to a wetland environment and the interior will be mostly be inaccessible to vehicles. The full transformation will take several decades but soon the Fakahatchee will benefit from the additional water flowing southeast.

Tony Marx is a Florida Master Naturalist and a Board Member of Friends of Fakahatchee. He was one of the speakers at our Annual Dinner on April 13.