Wednesday, October 31, 2012

Undertaker – The Crested Caracara

Originally published on Audubon Guides on October 14th, 2012
Throughout Florida’s rural landscape, thousands of miles of asphalt scars bisect pasturelands and create obstacles for every species of wildlife including rodents, frogs, owls, pigs, bears, panthers and so many more. A desolate wilderness is not a promise of safe harbor and the roadsides are often littered with carcasses of the quick…and yet dead.

A ghoulish gaggle of Turkey Vultures and Black Vultures often accompanies the funeral service, completing the deceased’s transition from life to death. Vultures feed primarily on carrion, although Black Vultures will assist in dispatching creatures still clinging to life. With weak talons and slow flight, they are ill equipped to chase and kill anything with much more spirit.
Crested Caracara and Turkey Vulture © Pete Corradino
In south central Florida, one of the rarest birds in the state can be seen in pairs, crowding a flock of vultures and dominating a carcass. The Crested Caracara, also found in Texas and Arizona is endangered in Florida in part due to increased agriculture lands. The roads that bring the roadkill also put the caracaras at risk of becoming roadkill themselves.

While the Crested Caracara is sometimes referred to as a Mexican Eagle, it is a member of the Falcon family, albeit in the much slower genus Caracara. The long-legged, sharp-beaked bird of prey is capable of chasing down its quarry and spends much of its time hunting on the ground. They are opportunistic and will feed on reptiles, small mammals and invertebrates but the preference in the prairielands is easy game, aka dead stuff.

The Crested Caracara is distinctly different in appearance from its undertaker associates. They look like a small Bald Eagle with a toupee. Their white neck and flight feathers against a body of brown set them apart from the mostly black vultures. Caracaras also have a stout orange beak with a blue tip. I often see them perched on fence posts, snags or in Slash Pines when not feeding on roadkill. The kill sites are always dynamic with an obvious pecking order among vultures and caracaras. Regardless of the number of vultures, a pair of caracaras will always dominate. It helps to be a Falcon and makes the job that much easier of an undertaking.

Sunday, October 28, 2012

iPed Shuffle – The Southern Stingray

Originally published on Audubon Guides on July 30th, 2012

From May through October, anyone heading into Florida’s coastal waters is encouraged to do the “stingray shuffle”. This Frankenstein’s monster-like gait stirs the underwater sediments and frightens the bottom dwelling rays into taking off. No doubt this aquatic march is a Sand Dollar’s (Echinarachnius parma) worst nightmare.

The Southern Stingray (Dasyatis americana) is the most common ray found along Florida’s coast. Its range extends from New Jersey south through the Gulf of Mexico and down the Atlantic coast to Brazil. This relatively flat-bodied, cartilaginous fish is related to sharks, whom happen to be one of their main predators. Despite their venomous bite and stinging barb, the stingray is non-aggressive, but those that don’t heed the “shuffle” warnings run the risk of stepping on one when they enter the water. Stingrays will burrow into the sand to rest and if stepped upon will involuntarily slap their four inch barbed tail up at the offender.
Southern Stingray
Southern Stingray © Graeme Teague
Less than two thousand incidences occur each year in the United States and most of them are minor injuries around the feet and ankles. The knife-like barb is serrated on both edges and terminates at a venom gland at the base which is equipped with a serious nerve toxin. Rarely is the injury serious or fatal and can be treated initially by immersion in hot water which breaks down the proteins in the venom and eliminates the pain. Further treatment is suggested.
If anyone should feel threatened it’s the clams, oysters, mussels, tube worms, coquinas, sand fleas, sand dollars, shrimp and even octopus that the stingrays feed on. The bat-like fish will flap its wings to uncover critters in the sand or blow water over the sand to achieve a similar effect. It even possesses an acute sensory system that detects its prey’s electrical field but most commonly uses its sense of smell.
What is harder to detect is a foot descending from the world above the waves. If you’re heading to the beach in stingray territory, make sure you shuffle; you never know what will surprise you.

Thursday, October 25, 2012

Suckers – The Common Octopus

Originally published on Audubon Guides on July 23rd, 2012

A friend called me the other day and asked me why we don’t have octopuses in Florida. “Why?” I questioned. Apparently someone she knew was going snorkeling on the reefs in Biscayne National Park off the coast of Miami. The woman was deathly afraid of octopuses and wanted to make sure the world beneath the waves was devoid of the well-suckered ones. I laughed. We have plenty but they’re nothing to worry about.

Octopuses are mollusks, more specifically cephalopods. They’re related to snails, slugs, clams, oysters and squid. Like any carnivore, they come well equipped to hunt. Like any prey species, they are well equipped to defend themselves. Their greatest weapon perhaps is their brain, a well-developed organ with the processing power that rivals some birds and fish. Not bad for an invertebrate species in the same phylum as the slugs.

All octopuses are venomous and can secrete a chemical from their salivary glands that incapacitates prey (The only octopus that secretes a deadly neurotoxin is native to the oceans around Australia). A powerful parrot-like beak allows them to puncture the shell of their prey which is mainly mollusks and crustaceans. Cephalopod means “head” and “foot”, a perfect characterization of a massive head seemingly mounted on four pairs of legs. Each leg is armed with rows of hundreds of suckers that prevent prey from escaping their powerful grip.

Most fascinating is the ability of the octopus to change colors dramatically within seconds. The malleable mollusk is capable of squeezing and relaxing muscles that control chromatophores, specialized cells that contain a variety of pigments. These cells can mimic the color, texture and brightness of the octopus’s surroundings, enabling them to blend into their surroundings in an instant and not only ambush prey, but hide from predators.

If you snorkel or dive in Florida you will be among octopuses. The Common Octopus (Octopus vulgaris) is the – ahem – most common. You may not see them but they will most likely see you. Fear not, their preference is to remain camouflaged and undiscovered.

During a recent trip to the Mote Marine Laboratory in Sarasota, FL my son and I watched an octopus in an aquarium scramble across the interior glass and duck into a corner – in plain sight. It turned from a bright red to a mottled brown color. A pair of visitors ambled up, looked into the tank, scanning past the octopus and complained, “There’s nothing in here”.

Tuesday, October 23, 2012

Olympic Wake Zone – The West Indian Manatee

Originally published on Audubon Guides on August 6th, 2012
Who wouldn't tune in to watch a showdown between the “slow moving”, baked potato-shaped  West Indian Manatee (Trichechus manatus)  and an Olympic gold medalist swimmer? Few people would put money on the bulbous beast to win a race against any human let alone an Olympian, the fastest of which can swim nearly 4 ½ mph. Surprisingly, the aquatic plant-munching manatee lazily drifts along at 3-5 mph and when pressed can zip along at 15 mph—three times faster than an Olympian.
West Indian Manatee
West Indian Manatee and calf © Jungle Pete
As of the start of the 2012 London Games, swimmer Michael Phelps had won 16 medals in the 2004 and 2008 Olympics. He stands a sleek six feet four inches and weighs around 185 pounds. Compare that to the barrel-shaped manatee that can weigh over 1200 pounds and reach lengths of thirteen feet long it’s hard to believe this would even be a contest but it is – in the manateesfavor.
Despite their ability to swim rapidly in short bursts of speed, manatees are often victims of collisions with watercraft that can seriously injury or kill them. It has been disproven thatmanatees cannot hear approaching boats. The question remains – why don’t they escape? Is their reaction time too slow? Is there too much auditory stimulus to sort out?
In 2011, Florida Fish and Wildlife conducted their annual manatee survey and counted 4834 – the second highest number since surveys began in 1991. That same year, 453 confirmed manatee deaths were recorded in Florida’s waters. Eighty-eight deaths were attributed to watercraft collisions including impacts and propeller wounds. One hundred and twenty deaths were undetermined and in the wake of an extended cold spell, 112 died from cold stress.
While wake zones have been established in high traffic manatee areas, boater complacency and accidental collisions still occur. Every year we continue to lose roughly ten percent of themanatee population, but many of those losses can be prevented through respect of their habitat by boaters and access to natural springs and warm water discharge from power plants.
Many tune in to watch the grace and athleticism of the Olympians competing in London. Consider There’s a show going on under the sea too, if only more of us would slow down and enjoy it.

Monday, October 22, 2012

Ghost Hunters, Part IV

Originally posted on Audubon Guides on July 16th, 2012

My companions take the first step into the duckweed (Lemna valdiviana) covered muck. It stirs slightly and closes back in over the black water as they wade out into the slough. “Something moved in the water” one of them says. “Probably a snake”. I’ve seen Cottonmouths (Agkistrodon piscivorus) out here in the past, most notably one that bobbed to the surface after I stepped on it. They can inject venom with an underwater bite. I got lucky. We carry sticks for balance, to probe the water depth and to check for critters. We can’t dismiss the American Alligator (Alligator mississippiensis) either. We believe there’s not enough food for an alligator out here yet. At least that’s what we’re telling ourselves.

With each step we look a few feet above us. Ghost Orchids are leafless plants that have recognizable green-white cord like roots that radiate from a center point. They typically grow 6-10 feet above the water on Pop Ash and Pond Apples which provide excellent cover and trap the perfect amount of humidity for these epiphytes to thrive.
My one mistake of the day sets me on edge for the rest of it. As I wade into deeper water I sidestep an unseen fallen branch at my feet. I plunge from knee depth to hip deep in a second and suddenly my cameras, which I've raised over my head are not my biggest concern. I safely scramble onto a dry island and consider the importance of my walking stick.

I pick up the “trail” – a loose separation of duckweed that my companions have slogged through and continue hip deep at a cautious pace. They have found the first Ghost, a double with two blooms floating to either side of the host tree trunk.
The decision is made to check the edges of the slough as the plants in the middle seem to have bloomed early. I gratefully make my way out of the deep water as my shoes make one last sucking gasp as the mud releases them. Two year ago we found four Ghosts in another slough. Suddenly we were surrounded by them. Several were just blooming, some wilting and others in full resplendent glory. We found singles, doubles and one triple blossom plant – 22 all told.
Ghost Orchid twins © Pete Corradino
As I wrap my head around our good fortune I hear whispers. Babbling sounds from the center of the swamp. Am I imagining this? It sounds like people but we are out in the middle of nowhere. After a few moments, three strangers make their way across the slough and beam in on a flower their GPS has led them to. We introduced ourselves and left them to their work. That’s when we found this beautiful “triple” double, a double blossom with a single blossom growing from a neighboring plant. Beautiful.
After all of that, I’m afraid it’s time to head back the way we came in. 

Saturday, October 20, 2012

Ghost Hunters, Part III

Originally posted on Audubon Guides - July 9th, 2012

Fear is an acceptable emotion that can lead to a heightened sense of awareness and ultimately protect one from a potential threat. I’m not afraid of ghosts. Nor am I afraid of seeking them but there are situations involved in the hunt that make you pause and consider that what you are doing is extremely dangerous and each step must be made with the greatest level of caution. The reward is ephemeral – 22 ivory white Ghost Orchid (Dendrophylax lindenii) blossoms floating under a canopy of Pop Ash (Fraxinus caroliniana) and Pond Apples (Annona glabra) in the midst of Florida’s greatest wildernesses – the Everglades.

The first step off the unpaved road is a hot one. Sawgrass (Cladium jamaicense) radiates intense heat and although it’s just after 8 AM, it feels like someone opened the oven door. Drainage efforts over the years have created high and dry ecotones, where welcoming shade comes from Slash Pines (Pinus elliottii) along the trail. A Black Bear (Ursus americanus) footprint reminds us that we are not alone out here. This doesn’t concern me. The bear mostly likely knows we are here and has gone in the other direction.
Black Bear tracks
Eventually the slightest elevation change brings us through a transition zone where towering Pond Cypress (Taxodium ascendens) draped with briars make the narrowing trail all the more difficult to traverse. There is no water here yet, but by the end of the rainy season, it will be two feet deep where we stand.
As the elevation plummets by the inch, the canopy closes in, the temperature drops nearly 20 degrees and we come to the edge of the water. The rainy season began a month back and the sloughs of the Everglades have been the first to fill. The limestone has been carved out by flowing water and has created the perfect environment for Pop Ash, Pond Apples and an assortment of native, spectacular orchids.

(to be continued)