Frosted Flatwoods Salamanders: Recovery, Redundancy, and Fire

by Dani Davis

Crouching in the rain, searching for eggs

The dark sky finally opened up, and rain began falling on us as we crouched down in the wet grass, searching for frosted flatwoods salamander eggs. I hear the pitter-patter of raindrops bouncing off of my backpack as I watch Pierson Hill, a biologist for the Florida Fish and Wildlife Conservation Commission (FWC), carefully extract a cluster of small, shiny eggs. He carefully places the clutch in a plastic sweater box that had been filled with soft, wet mud and presses the outside of the cluster down into the mud to keep them from sliding around during the trip back to the lab. Looking closely, I can see the embryos of baby salamanders wriggling around in the eggs.

Pierson Hill pushes apart grasses to reveal a cluster of frosted flatwood salamander eggs
Pierson Hill pushes away grasses to reveal a cluster of frosted flatwoods salamander eggs
A frosted flatwoods salamander egg cluster is gently placed in a mud-lined sweater box to prevent them from drying out and shifting around during transport.
The egg cluster is gently placed in a mud-lined sweater box to prevent them from drying out and shifting around during transport.

Our visit is not the first trip to this pond. Pierson repeats this process tirelessly with a team of field technicians who spend the entire egg-laying season (late fall) crouched in the grass, looking for eggs. Many days are spent in the mud, dodging annoyed cottonmouths, bent over with your face in the grass. Once eggs are eventually found, they are carefully cut away from the vegetation and carefully moved into safekeeping. This is not easy work and requires a lot of time and energy – for a single salamander species. How important, rare, or valuable must a species be to prompt this level of dedication?

A common sight in the fire-maintained wetlands. This cottonmouth was very annoyed that we were disturbing her.
A common sight in the fire-maintained wetlands. This cottonmouth was very annoyed that we were disturbing her.

From hundreds of thousands to a few hundred

“150 years ago, they were probably in hundreds of wetlands out here, and there were hundreds of thousands of them” Pierson calls out while carefully sifting through the grass for eggs.

Now, there are only a couple of areas where frosted flatwoods salamanders are still found. Populations of salamanders are mostly spread between St. Marks National Wildlife Refuge and the Apalachicola National Forest (ANF), where their numbers are critically low. Pierson believes that 100 – 500 salamanders are left in ANF, with maybe as few as 30 – 60 mature, egg-laying females. With the population at such low numbers, the frosted flatwoods salamander is considered “functionally extinct .” This term is used when a species is still present in its natural habitat but is no longer filling its role in the ecosystem.

one of the last remaining wetlands with breeding frosted flatwood salamanders
One of the last remaining wetlands with egg-laying frosted flatwood salamander mothers. Note the fluffy, fire-maintained grasses covering ground.
looking upslope from the wetland, herbs and grasses fill the open flatwoods
The view looking out of the wetland is a lush savanna filled with native, fire-maintained grasses and herbs.

Fire is absolutely critical

Their decline follows the decline of many of our threatened and endangered species in the Apalachicola Lowlands ecoregion, a loss of frequent, growing-season fire on the landscape. Traditionally, a large portion of the southeastern Coastal Plain, including the habitat range of the frosted flatwood salamander, burned every few years during seasonal fires. These periodic fires would have occurred most often in the summer when large thunderstorms roll through the landscape bringing fire-igniting lightning.

pitcher plants stand among the grasses, another fire-depended species.
Fire maintains many of the rare species found on our flatwoods, like Sarracenia flava, the yellow pitcher plant. Checkout our recent search for carnivorous plants in the Apalachicola Lowlands, when bright new pitchers were emerging.

Unlike the devastating fires that we hear about in the western United States, these fires would have been low-burning fires that would sweep through the forest floor, burning up the low-growing plants. This seasonal fire cycle leads to an ecoregion full of plant and animal species specially adapted to fire. The flatwoods salamander, the ponds they rely on, and the plants where they hide their eggs all depend on fire to create an open, wetland habitat.

looking back at the wetland - a stand of cypress trees stand in a circle surrounded by open flatwoods.
The flatwoods are a fire-maintained mosaic of habitats. Wetlands like this one are surrounded by flatwoods and savannas

The importance of fire has been recognized in Apalachicola National Forest, and prescribed fire, a controlled fire set by people for habitat improvement, has helped restore some of these habitats. However, there is a problem here for the wetlands. Prescribed fires typically occur in the winter, when the ponds are full of water, rather than in the summer when the wetlands are dry – leading to a cycle where wetlands don’t burn. This leads to a shift in the wetland plant community, from the grasses that salamanders rely on to shrubby thickets.

a shrubby wetland with a closed canopy.
When fire doesn’t reach wetlands, they turn into closed-canopy, shrub dominated areas. This wetland no longer supports flatwoods salamanders and other amphibians that depend on open wetlands

“Prescribed fires have almost completely replaced natural fires, and prescribed fires are not performed at the same frequency, intensity, and seasonality as wildfires,” Pierson explains, “what the forest service has been doing in partnership with FWC and The Nature Conservancy is getting contract crews to come into these ponds and do mechanical restoration… they hack out the understory shrub and midstory hardwood layer, and they haul it out into the surrounding uplands”.

This mechanical restoration helps restore these wetlands to a state where fire can easily move through them, producing the ideal habitat for salamanders. The plight of the salamanders doesn’t end there, though.

a tree dominated wetland that has been cleared of shrubs - in the process of being restored to a fire, maintained open wetland
A wetland in transition. Many of the shrubs have been cleared out, but leaf litter has built up on the wetland floor – altering the water table and creating a less ideal habitat for salamanders. With successive fires, this wetland will return to a state where it will be a more ideal habitat for breeding amphibians.
And here we see an ephemeral wetland that has been maintained with fire, the ground open and grassy.
And here we see an ephemeral wetland that has been maintained with fire, the ground open and grassy. Such a habitat is an ideal breeding wetland for the frosted flatwoods salamander.

Extreme swings in weather patterns are making things more difficult

While crouching in the grass searching for eggs in the light fall rain, Pierson continues, “with all of the habitat restoration going on, these ponds are becoming better and better, but salamanders are still not responding due to weather.”

The salamanders evolved in a climate where we would have a dry fall, leading to the drying of the ponds that removes any fish that would compete or eat the salamander and a wet winter. What we’re seeing though, is extremes in weather. Where ponds never dry down leading to ponds that become dominated by fish communities, or where droughts lead to no water in the wetlands. The culprit? Climate change.

We can’t expect the weather to be less erratic, climate change isn’t going away, but through programs like FWC’s frosted flatwoods salamander program, we can slow the extinction rate and, hopefully, establish more populations.

Pierson uses a headlamp to search for eggs in between grasses
Pierson uses a headlamp to search for eggs in between the grasses.

Giving frosted flatwoods salamanders a head start

While continuing to sift through soft grasses, Pierson explains, “Minimally we can prevent the eggs from drying up and dying if it’s a bust year.” There is a lot stacked against the frosted flatwoods salamander, but this is why Pierson and his crew spend hours in the field, bent over, searching for eggs of the frosted flatwoods salamander, and months tending to them in small, protected pools.

a gray sweater box sits on a plastic table. the sweater box is full of damp mud and is dotted with clusters of salamander eggs
Back in the lab, a sweater box filled with eggs sits on a table where they are carefully monitored.

Salamander eggs are collected and moved to the USFS workstation near Bristol as a part of the FWC “head-starting” program. The idea of head-starting a species is to protect them during their most vulnerable life stage, for the frosted flatwoods salamander; that’s when they’re larvae. Salamanders go through a few stages; starting as eggs, they hatch out to become aquatic larval salamanders, complete with gills, and then metamorphose into air-breathing adults after a few months.

Tiny frosted flatwoods salamanders are visible inside the clear eggs.
Tiny frosted flatwoods salamanders are visible inside the clear eggs.

Protected ponds provide a safe place for salamanders to grow up

Once adults, the salamanders’ black and white speckled color helps them blend in with the soft, wet soil where they hide from predators. The larval salamanders also have camouflage coloring; their bodies are striped with tans and browns to blend in with the grass but are much more vulnerable to being eaten. As larvae, they’re confined to the water where wading birds and raccoons will happily gobble them up. The salamanders are protected during this vulnerable stage through the head-starting program, helping to ensure many of the larval salamanders make it to adulthood.

Rows of blue, plastic pools are lined up in rows. each one is filled with water and grasses

Ponds, also called “mesocosms”, are filled with grasses and support a food web of tiny creatures that will eventually feed hungry larval salamanders.

In their natural habitat, the eggs would hatch as the rains picked up in the winter – as being immersed in water signals the egg that it is time to open up. Instead of relying on rains in the head-starting program, the team has an array of large pools set up, complete with its own ecosystem, ready to receive (and feed!) newborn salamanders. Once the eggs collected from the field are ready to hatch, Pierson and his team plops them into the salamander-ready pools. Just like in the wild, the water spurs the eggs to hatch and out pop larval salamanders. The larval salamanders then spend the next few months (usually about January – April) in the pools until they transform into air-breathing adults.

looking inside one of the pools, Pierson is reflected off of the water. Grasses float on top of the surface
Peering inside one of the ponds to get a closer look at the ecosystem that Pierson and his team creates to feed and support larval salamanders.

Climate change is throwing a wrench into recovery efforts

In most years, Pierson and his crew release the salamanders either as large larvae or as freshly transformed adults. This year, things have been different. Because of erratic weather patterns during the egg-laying period, when the ponds were overflowing, the salamanders laid their eggs farther upslope than usual. This made egg finding extremely difficult, and significantly fewer eggs were collected than expected – only about 300. To make matters worse, these 300 individuals were cut down to about 100 due to contaminated equipment, which the FWC crew was unaware of until it was too late.

A larval frosted flatwoods salamander floats in one of the ponds. The gold, feathery appendages around its head are its gills - which it will lose when the larval salamander transforms into an adult.
A larval frosted flatwoods salamander floats in one of the ponds. The gold, feathery appendages around its head are its gills – which it will lose when the larval salamander transforms into an adult.

There is a ray of hope here, though. For the first time, frosted flatwoods salamanders were bred in captivity at the Amphibian Foundation in Atlanta, Georgia. This is a huge step forward for the conservation of this species as captive-bred individuals can be released onto the landscape to bolster and establish new populations of flatwoods salamanders. With this in mind, Pierson has decided not to release the 100 individuals – but to instead send these salamanders to partner organizations that can rear them for captive breeding.

Redundant populations, and a strong network of passionate people, are necessary for salamander recovery

Pierson stresses the importance of what conservation biologists call “redundancy.” This essentially means that there are more populations on the landscape to ensure that the extinction of one population doesn’t lead to the species’ demise. Redundancy, multiple populations, is critical for a species threatened by a constant threat – like climate change. Establishing various frosted flatwoods salamander populations across its historical range, the coastal plains of the southeast, would ensure that there would be backup populations to ensure that the entire species doesn’t go extinct because of an erratic rainfall year in one region. Captive-bred salamanders could be the key to establishing these redundant populations.

Pierson crouches in a grasses field looking into the grasses
Pierson explains the threats to flatwoods salamanders while searching for the few eggs that remain on the landscape.

The path forward won’t be easy, but through the dedication of biologists like Pierson and the partner organizations he works with – the frosted flatwoods salamander stands a chance of reestablishing in the fire-maintained wetlands that they call home. It will take the cooperation of a vast network of individuals. Still, with so many passionate people fighting to protect this species, steps are being taken to prevent the total extinction of this incredible member of our forests.

Frosted flatwoods salamander woodblock print by Dani Davis.
Frosted flatwoods salamander woodblock print by Dani Davis.
Closeup of a frosted flatwoods salamander in its egg.
Closeup of a frosted flatwoods salamander in its egg.
To the left, and ephemeral wetland.  To the right, a longleaf savannah.
To the left, and ephemeral wetland. To the right, a longleaf savannah.
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