Birds, migration, and climate change. Mix them all together and intuitively, we can imagine an ecological train wreck in the making. Many migratory bird species have seen their numbers plummet over the past half-century – due not to climate change, but to habitat loss in the places they frequent as part of their jet-setting life history.
Migrating songbirds forage for insects in coastal scrub-shrub habitat. Photo credit: Erik Lovestrand, UF IFAS Extension
Now come climate simulation models forecasting more change to come. It will impact the strands of places migrants use as critical habitat. Critical because severe alteration of even one place in a strand can doom a migratory species to failure at completing its life cycle. So what aspect of climate change is now threatening these places, on top of habitat alteration by humans?
It’s the change in weather patterns and sea level that we’re already beginning to see, as the impacts of global warming on Earth’s ocean-atmosphere linkage shift our planetary climate system into higher gear.
For migratory birds, the journey itself is the most perilous link in the life history chain. A migratory songbird is up to 15 times more likely to die in migration than on its wintering or breeding grounds. Headwinds and storms can deplete its energy reserves. Stopover sites for resting and feeding are critical. And here’s where the Big Bend region of Florida figures prominently in the life history of many migratory birds.
According to a study published in March of this year (Lester et al., 2016), field research on St. George Island documented 57 transient species foraging there as they were migrating through in the spring. That number compares favorably with the number of species known to use similar habitat at stopover sites in Mississippi (East Ship Island, Horn Island) as well as other central and western Gulf Coast sites in Alabama, Louisiana, and Texas.
We now can point to published empirical evidence that the eastern Gulf Coast migratory route is used by as many species as other Gulf routes to our west. This confirmation makes conservation of our Big Bend stopover habitat all the more relevant.
The authors of the study observed 711 birds using high-canopy forest and scrub/shrub habitat on St. George Island. Birds were seeking energy replenishment from protein-rich insects, which were reported to be more abundant in those habitats than on primary dunes, or in freshwater marshes and meadows.
So now we know that specific places on our barrier islands that still harbor forests and scrub/shrub habitat are crucial. On privately-owned island property, prime foraging habitat may have been reduced to low-elevation mixed forest that is often too low and wet to be turned into dense clusters of beach houses.
Coastal slash pine forest is vulnerable to sea level rise. Photo credit: Erik Lovestrand, UF IFAS Extension
Think tall slash pines and mid-story oaks slightly ‘upslope’ of marsh and transitional meadow, but ‘downslope’ of the dune scrub that is often cleared for development.
“OK, I get it,” you say. “It’s as if restaurant seating has been reduced and the kitchen staff laid off. Somebody’s not going to get served.” Destruction of forested habitat on our Gulf Coast islands has significantly reduced the amount of critical stopover habitat for birds weary from flying up to 620 miles across the Gulf of Mexico since their last bite to eat.
But why the concern with climate change on top of this familiar story of coastal habitat lost to development? After all, we have conservation lands with natural habitat on St. Vincent, Little St. George, the east end of St. George, and parts of Dog Island and Alligator Point. Shouldn’t these islands be able to withstand the impacts of stronger and/or more frequent coastal storms, and higher seas – and their forested habitat still serve the stopover needs of migratory birds?
Let’s revisit the “low and wet” part of the equation. Coastal forested habitat that’s low and wet – either protected by conservation or too wet to be developed – is in the bull’s eye of sea level rise (SLR), and sooner rather than later.
Using what Lester et al. chose as a reasonably probable scenario within the range of SLR projections for this century – 32 inches, these low-elevation forests and associated freshwater marshes would shrink in extent by 45% before 2100. It could be less; it could be more. Conditions projected for a future date are usually expressed as probable ranges. Experience has proven them too conservative in some cases.
The year 2100 seems far away…but that’s when our kids or grandkids can hope to be enjoying retirement at the beach house we left them. Hmm.
Scientists CAN project with certainty that by the time SLR reaches two meters (six and a half feet) – in whatever future year that occurs, 98% of “low and wet” forested habitat will have transitioned to marsh, and then eroded to tidal flat.
But before we spool out the coming years to a future reality of SLR that has radically changed the coastline we knew, let’s consider where the crucial forested habitat might remain on the barrier islands of the next generation’s retirement years:
It could remain in the higher-elevation yard of your beach house, perhaps, if you saved what remnant of native habitat you could when building it. Or if you landscaped with native trees and shrubs, to restore a patch of natural habitat in your beach house yard.
Migratory songbird stopover habitat saved during beach house construction. Photo credit: Erik Lovestrand, UF IFAS Extension
We’ve all thought that doing these things must be important, but only now is it becoming clear just how important. Who would have thought, “My beach house yard: the island’s last foraging refuge for migratory songbirds!” even in our most apocalyptic imagination?
But what about coastal mainland habitat?
The authors of the March 2016 St. George Island study conclude that, “…adjacent inland forested habitats must be protected from development to increase the probability that forested stopover habitat will be available for migrants despite SLR.” Jim Cox with Tall Timbers Research Station says that, “birds stop at the first point of land they find under unfavorable weather conditions, but also continue to migrate inland when conditions are favorable.”
Migratory birds are fortunate that the St. Marks Refuge protects inland forested habitat just beyond coastal marshland. A longer flight will take them to the leading edge of salty tidal reach. There the beautifully sinuous forest edge lies up against the marsh. This edge – this trailing edge of inland forest – will succumb to tomorrow’s rising seas, however.
Sea level rise will convert coastal slash pine forest to salt marsh. Photo credit: Erik Lovestrand, UF IFAS Extension
As the salt boundary moves relentlessly inland, it will run through the Refuge’s coastal buffer of public lands, and eventually knock on the surveyor’s boundary with private lands. All the while adding flight miles to the migration journey.
In today’s climate, migrants exhausted from bucking adverse weather conditions over the Gulf may not have enough energy to fly farther inland in search of forested foraging habitat. Will tomorrow’s climate make adverse Gulf weather more prevalent, and migration more arduous?
Spring migration weather over the Gulf can be expected to change as ocean waters warm and more water vapor is held in a warmer atmosphere. But HOW it will change is difficult to model. Any specific, predictable change to the variability of weather patterns during spring migration is therefore much less certain than SLR.
What will await exhausted and hungry migrants in future decades? Our community decisions about land use should consider this question. Likewise, our personal decisions about private land management – including beach house landscaping. And it’s not too early to begin.
Erik Lovestrand, Sea Grant Agent and County Extension Director in Franklin County, co-authored this article.
The American Alligator is an icon in the state of Florida. Viewed on the program “Swamp People” and as the mascot of the University of Florida, most visitors to our state view this animal more on television than in the wild; but they are certainly there. In need of mates and calories from the lack of eating over the winter, alligators and other reptiles become more active this time of year. Visitors and residents alike should be a little more cautious.
Alligator basking on the Escambia River; photo: Molly O’Connor
Like most predators, alligators seek food that will provide them energy. Generally predators will target prey that will cost them very little energy to capture and kill. Obviously small alligators will feed on small prey but adult alligators feed on smaller prey than many think. Fish, turtles, snakes, small mammals and birds make up the bulk of their diet. If the opportunity presents itself, and they do not have to expend too much energy, alligators will certainly take larger mammals and birds.
For humans the bigger problem has been the loss of pets and livestock. Small dogs are certainly easier prey than a human, and with the loss of habitat encounters with humans and their pets have increased. Since 1948 FWC has estimated about 300 alligator attacks on humans directly, less than 10% of these were fatal. As more alligators are forced into suburban areas more encounters have occurred. In the last 10 years 16,000 nuisance alligator calls have been reported to the FWC. As with other wildlife, like coyotes, many of these animals are living in ditches and other watering holes where they seek fish and turtles. However if we visit such places, particularly with our pets, these animals may certainly make an attempt to grab them. If you feel an alligator is a nuisance and could be a potential problem you can call FWC at (866) FWC-GATOR; (866) 392-4286). Folks should be aware that FWC does not relocate nuisance alligators, they will be destroyed. Currently FWC issues about 7000 permits for alligator control across the state.
A couple of safety notes if you live near waterways with alligators.
- Do not swim in these locations at night; alligators are more active hunters between dusk and dawn
- Try to discard fish remains after cleaning in another location besides the water; if these locations have a few alligators they will certainly learn this habitat and hang around the boat ramp more.
- DO NOT FEED alligators; help us let visiting tourists know this and that it is illegal in our state. Alligators fed by humans will eventually lose their natural fear of us and this could bring on problems.
These are awesome animals. We should better understand their natural history so that we can exist with them. For more information on alligators in your area contact your county extension office.
Canoeing in Perdido River Photo credit: Carrie Stevenson
This time of year, many families are looking for ways to entertain their kids during spring break. For those not planning to travel far, our area is full of fun, and often inexpensive, outdoor adventures.
As part of a series of field excursions led by Extension Agents over the past few years, we’ve been able to introduce visitors and lifelong residents of the panhandle to some tremendous natural resources that are right at our back door.
Following are three examples of family friendly trips worth marking off your “Florida bucket list.”
Perdido River: the natural border between Alabama and Florida, the Perdido stretches over 65 miles from its source near Atmore, Alabama and ends up at Perdido Key in the Gulf. Clean, clear, and sandy-bottomed, the Perdido River is a perfect spot to tube, kayak, canoe or paddleboard and several local outfitters can provide equipment. While on the river, you might experience a flyover from a bald eagle, see towering bald cypress, or explore shallow backwater springs and swamps.
Majestic bald cypress trees serve as wildlife habitat at Wakulla Springs State Park. Photo credit: Carrie Stevenson
Further east is Florida Caverns State Park in Marianna. This region is one of the most biodiverse in the state, with endemic tree species—like the Florida Torreya, found only in three counties in the state—along with many hardwood species found more typically in the central Appalachians. The extensive limestone cavern and spring systems in Jackson County are home to beautiful swimming/diving spots as well as the caverns. The ranger-led tours are excellent, as well as the hiking trails within the park grounds. The cave tour takes about an hour and is mildly strenuous. There are no tours on Tuesday or Wednesday, so keep this in mind when planning a visit.
The crystal clear springs of Wakulla are home to alligators and manatees. Photo credit: Carrie Stevenson
At the edge of our district is Hollywood-famous Wakulla Springs. Film site for both “Tarzan” and “Creature from the Black Lagoon”, the spring teems with wildlife year-round. A guided tour via pontoon boat will bring you up close to manatees, alligators, ospreys, anhingas, and large herons. Hiking trails, a swimming hole, and the historic lodge and restaurant are open to visitors as well. The nearby Chipola River is also a beautiful spot to paddle.
Every county in the Florida panhandle has tremendous water resources, from the Gulf to inland rivers and even waterfalls. Take time to explore on your days off this spring!
In the last few weeks we have received an increase in calls about snake encounters. Most of these have dealt with small juvenile snakes folks are finding on their property, or in their homes, but we are also hearing about large ones.
Corn snakes are excellent climbers and consume a lot of rodents.
Photo: Nick Baldwin
Most of the 56 species of snakes found in the southeastern United States breed in spring or summer and this time of year people begin to encounter the juveniles from this year’s brood. The Southern Black Racer has been the most common encounter we have heard from and this is because the young do not resemble the adults at all. But panhandle residents should be aware that there are several species who do breed in the fall and the adults will be seeking each other this time of year increasing your chances of an encounter. Of those that do breed in the fall 16 can be found in the panhandle.
Three of these species are small terrestrial snakes. They would include the Florida Red-Bellied Snake, the Southeastern Crown Snake, and the Southern Ringneck Snake. These are typically less than 15” in length and move at night. They frequent the underbrush where they hunt for insects and small amphibians and are no threat to people or pets.
There are 4 species of local mid-sized snakes that are fall breeders. The Rough Green Snake, Eastern Garter Snake, Eastern Hognose Snake, and the Scarlet Snake are all very common and pose no threat to people and pets. The Green Snake and Scarlet Snake can be found in around trees this time of year and the Eastern Hognose is often confused with the Pygmy Rattlesnake. Hognose differ in that they have round pupils and an upturned nose; of course they lack a rattle as well. Scarlet snake is confused with the Eastern Coral Snake but can be distinguished but their red head (instead of black).
Gray rat snake crossing a driveway.
Photo: Carrie Stevenson
Of the 8 species of large terrestrial snakes only 2 are known to breed in the fall locally. These would be the Gray Rat Snake and the Eastern Indigo. Both of these snakes can easily reach 6 ft. in length and tend to terrify people but in reality these are both rather docile and consume a significant number of disease carrying rodents; Indigos will actually feed on venomous snakes helping to control their populations. The Eastern Indigo Snake has not been seen in the Florida panhandle since the late 1990’s and is current listed as an endangered species in our state.
We have 15 species of non-venomous water snakes in the southeastern U.S. but only 1 local is a fall breeder; the Queen Snake. This snake is found in all panhandle counties except those along the coastal portion of the Apalachicola River; Bay, Gulf, Franklin, and Wakulla counties. As a group water snakes tend to be aggressive, and some can be quite large, but they pose no danger to people and pets.
Finally the ones most are concerned with. There are 6 species of venomous snakes in the southeastern U.S. All 6 can be found in the panhandle and all 6 breed in the fall. This means that males will be out seeking females and encounters could occur. Copperheads are rare in Florida but are most often encountered along the region of the Apalachicola River. These snakes tend to be cryptic and move very little. They will release a musk to warn that you are getting to close. There are 2 subspecies of Cottonmouths in the panhandle. The Florida Cottonmouth is found in the coastal counties of the Apalachicola River (mentioned) and the Eastern Cottonmouth is found elsewhere. They prefer water but will move upland during the cooler months. They have a reputation of being aggressive but are actually no more aggressive than other snakes. Like most, they are trying to avoid you. The Eastern Coral Snake is the only neurotoxic snake in our state. This animal moves through the underbrush seeking prey, including other snakes. They are rarely encountered but are quite common.
The familiar face of an Eastern Diamondback Rattlesnake.
Photo: Nick Baldwin
Then there are the most feared of the group – the rattlesnakes. The Timber Rattlesnake is actually not that common in Florida but many travel to Georgia and Alabama during deer season where they are common. The Eastern Diamondback and the Dusky Pigmy Rattlesnakes are common here. All three species breed in the fall and could be encountered this time of year.
Many of our local snakes will den during these cooler months and some in groups. All should be aware of this when exploring stump holes and such while visiting the outdoors. Also know that on warm sunny days they may venture out to bask in the sun; another chance to encounter them.
For more information on how to handle an encounter or a snake bite visit the Escambia County Extension website ( http://escambia.ifas.ufl.edu ) or contact Rick O’Connor at 850-475-5230; firstname.lastname@example.org .
“Imitation is the sincerest of flattery,” wrote Charles Caleb Colton. Colton was a sometimes cleric, essayist, wine merchant and gambler who bounced around Europe and North America during the early nineteenth century. It is likely many of his financial lenders hoped the public would not imitate his borrowing practices.
Aside from his few literary works and the catchy phrase above, he was most noted for running up debts then leaving for parts unknown.
Eye spots on a Luna Moths wings are meant to deceive potential predators into believing they are seeing another predator. Photo by Les Harrison.
Imitations are not looked upon kindly when lazy students, or journalists for that matter, complete an assignment by borrowing blocks of text. Plagiarism is a flunking and firing offense with career-ending potential.
The concepts of imitation and mimicry date back to the earliest written records of ancient Greece. The philosopher Plato used mimicry to define beauty and truth, and as a contrast to the negative aspects of life.
For the denizens of north Florida’s untamed regions, mimicry is a form of imitation which assures the survival of some. Survival always beats the alternative.
Insects are particularly effective at using several forms of mimicry to survive and reproduce in a very hostile environment where big hungry creatures always are on the prowl for their next meal. Eyes and disguise are the top tactics for continuation of the species. Multiple eyes on the bug’s face are common in the insect world. Large, eye-like spots on the rear of the bug are an effective form of defensive mimicry used by several local caterpillars species.
The saddleback caterpillar is a good example of how this deception is carried. There are two color-coordinated eye-like spots on the rump of this caterpillar. These spots are exponentially larger than the saddleback’s real eyes, which are barely visible without the aid of magnification. An approaching predator will quickly notice the blankly staring spots and likely recall the last encounter with this appropriately named creature.
Mature larvae of the saddleback caterpillar, Acharia stimulea (Clemens). Photo by Lyle J. Buss, University of Florida.
It is worth noting the saddleback caterpillar has more defensive weapons systems than an Ageis missile cruiser. The novice predator that attempts to dine on this colorful, plump morsel will always remember the experience.
In addition to insects and caterpillars, some spiders have eye-spots on their thorax. Depending on the circumstances, the hunter can easily become the hunted.
Juvenile water moccasins or cottonmouths are brightly patterned with a yellow tail tip that they wiggle mimic insects attracting small prey such as lizards, toads, and frogs. Photo courtesy of J. D. Wilson and the University of Georgia.
Another mimicry tactic is camouflage, the ability to blend into the background and avoid detection. Millions, if not billions, of dollars of hunting clothing is sold annually to provide deer and turkey hunters that perceived advantage over their potential trophy animal. Moths are quite adept at using this technique to hide in plain sight. In the wild they almost always rest or lay eggs on surfaces which closely resemble their color scheme.
The last form of mimicry occasionally seen is the lure. This method attracts the prey to its demise. A prime example is employed by young water moccasins which have a sulfur-yellow tipped tail. The tail is shaken to resemble a wounded insect as the snake hides in the leaf litter. The unwitting victim is surprised, no doubt, to discover its status as a menu item.
To learn more about how north Florida’s wildlife employs mimicry contact your local UF/IFAS County Extension Office.
Swamps provide valuable filtration for surface water
Recent rains have left water standing on some panhandle Florida real estate which has been dry for several years. Ponds, natural and dug, are brimming with water reflecting the generous outpouring from the slow and wet weather system which passed listlessly over the area.
The rainwater excess is also filling the natural low points known as swamps or wetlands.
A swamp is defined as a forested wetland. Some occur along the floodplain of rivers, where they are dependent upon surplus flow from upstream and local runoff.
Other swamps appear adjacent to ponds in shallow depressions which fill during wet periods. Their landscape is covered by aquatic vegetation or trees and plants which tolerate periodical inundation.
Historically, swamps have an image problem. Legend has all sorts of unsavory creatures, degenerates, and ghosts inhabiting the locale waiting for the unsuspecting traveler.
Even the proper British used the term as a pejorative to describe Francis Marion during the American Revolution. The Swamp Fox engaged in guerilla warfare against the conventional forces and hid in the swamps to avoid capture.
Economically, these watery regions have had very low values. Their only significance was as site for trapping, hunting or for logging in dry years.
Medically, swamps were seen as a quick and painful way to the grave. There were all those creatures which could inflict pain; leeches, snakes, gators and the like.
Then there was disease. As an example, the term Malaria originated from the swamps of southern Europe where it meant bad air in medieval Italian. The mosquito connection was unknown until the early 20th Century.
Hollywood piled on the problem with a series of swamp monster movies. One, “The Creature from the Black Lagoon” was partially filmed at Wakulla Springs in the panhandle.
Reality, as is often the case, is quite different than the initial perception. Even the term swamp has fallen out of favor in some circles, being replaced with wetlands.
Swamps or wetlands serve a variety of functions in north Florida. Possibly the most critical is as a filtration system for the water table.
Excess rain is held in these shallow depressions and allowed to percolate or filter slowly through the soil. The screening effect of the soil and subsoil layers along with the slow progression cleanses the water of numerous impurities from the surface.
Without the holding capacity of local swamp, most rainwater would end up in streams and rivers. In addition to being a loss for the water table, the excess water would cloud waterways with a glut of surface debris and nutrients.
It is true mosquitos favor the still swamp waters, but so do many birds, fish and animals. Swamp rookeries are the nesting home for many wading birds. Mosquito larvae are an important link in the food chain which supports much of the life in the swamp, and beyond.
Even some of the swamp’s most ostracized residents, snakes, have an important part to play in the overall environmental balance. These reptiles control the population of many destructive insects and rodents.
To learn more about the importance of Panhandle Florida’s swamps and wetland, contact your UF/IFAS Extension Office.