Written by: Rachel McGuire
Our third installment of the 12 Months of Aquatic Critters blog series is Aquatic Amphibians! Amphibians are small vertebrates that need water or a moist environment to survive. This group of critters breathes and absorbs water through thin skin. The vast majority of amphibian larvae are aquatic and undergo metamorphosis (there are several forms!) to become terrestrial, semi-terrestrial, or aquatic adults.
Amphibians are also ectotherms – meaning they are dependent on external sources of body heat. They are more sensitive to water pollution and/or habitat disturbances than most creatures. In this article, we’ll touch on most of the amphibians that have at least one life stage in water.
The approximately 80 species of amphibians of Alabama can be broken into two major groups: salamanders and frogs/toads:
SALAMANDERS
The Mole Salamanders (Ambystoma spp.)
This group of salamanders is popular with the masses with their chunky bodies, bold patterns, and prolific breeding migrations in winter triggered by heavy nighttime rains. Although these nocturnal salamanders are terrestrial, their breeding areas are aquatic – typically ephemeral pools, ditches, marshes, or ponds typically lacking fish (i.e. egg and baby salamander predators). The Friends of Shade Creek, a nonprofit in the Birmingham area, hosts an annual Salamander festival in late winter during the primetime of the mole salamander family’s yearly migrations to breed.
Ambystomids of Alabama include the federally endangered reticulated flatwoods salamander, spotted salamander, marbled salamander, mole salamander, small-mouthed salamander, and eastern tiger salamander.
Amphiumas
Amphiumas are eel-like salamanders found in swamps, seepages, and ponds. These critters are poorly understood and hard to detect. They have small, vestigial legs and are typically dark-colored (brown, gray, and black) and can grow to be nearly four feet long! These critters are carnivorous feeding on crayfish, fish, tadpoles, insects, and insect larvae. The three species found in Alabama are one-toed, two-toed, and three-toed amphiuma.
Eastern Hellbender
This fully aquatic salamander is the largest salamander in North America, growing up to 30 inches long! With a flattened body, loose skin folds, and short legs, this strange looking critter is known by many not-so-flattering names such as the snot otter, lasagna lizard, devil dog, and the Allegheny alligator. The hellbender is federally threatened in Alabama and endangered in much of its range. The hellbender is predominantly nocturnal, emerging at night to hunt crayfish, small fish, tadpoles, toads, and water snakes. The hellbender rarely swims, instead opting to crawl slowly along riverbeds. The hellbender is found in the Tennessee River Basin in Alabama.
Waterdogs/Mudpuppies
This group of salamanders stays in the water their entire lives. The waterdogs and mudpuppies are easily recognizable by their bushy external gills they retain into adulthood. Their bodies are typically flattened with a laterally compressed tail and oftentimes have spots. The rarest of this group is the federally endangered Black Warrrior waterdog which is only found in Alabama in the upper Black Warrior River Basin. Garden & Gun visited the Bankhead National Forest to sample for the Black Warrior waterdog in 2022. Other members are the Gulf Coast waterdog, and the mudpuppy.
Eastern Newt
The eastern newt, or red-spotted newt, is a unique salamander because it has an intermediate terrestrial form known as an eft between the aquatic larval and aquatic adult stage. The red eft is a nearly fluorescent orange, so bright it is easily mistaken for a child’s plastic toy lizard when seen on the forest floor. Eastern newts are found state-wide in Alabama.
Sirens
The greater siren, lesser siren, and recently discovered reticulated siren comprise the Alabama residents of this strange salamander group. These fully aquatic critters lack hind legs and retain their external gills their entire life, similar to the waterdogs and mudpuppies. Sirens are poorly understood and lack detailed life history information. The reticulated siren is endemic to coastal Alabama, the Florida Panhandle, and possibly southwest Georgia.
Lungless Salamanders
The Plethodon family is the largest group of salamanders worldwide with nearly 30 species in Alabama alone. These lungless salamanders rely on cutaneous respiration aka “skin breathing”, while the cave salamanders retain their gills into adulthood. Some of the lungless salamanders lack an aquatic larval stage, but most have a lengthy aquatic larval stage. There are many groups of closely-related salamanders referred to as “species complexes” that are so genetically similar that scientists are often divided on rather to split species or designate down to a sub-species level. Some of these species complexes include the dusky salamanders, dwarf salamanders, and slimy salamanders.
Some of the larger Plethodontids include the northern and southern red salamander and the federally threatened Alabama endemic: the Red Hills salamander. The Red Hills salamander is found in 6 Alabama counties, is the state amphibian, and can reach a length of 10 inches! The Red Hills salamander is found on north-facing steep slopes that are dominated by hardwood trees in complex burrow systems.
The pale cave salamander is found almost exclusively in the Tennessee River basin, is stygobitic, meaning it lives exclusively in groundwater such as cave systems and aquifers. It has bright red gills (which it retains into adulthood), depressed eyes, and is an opportunistic predator.
FROGS/TOADS
Treefrogs & Allies
Contrary to popular belief, the common trait amongst tree frogs and the allies isn’t that they all live in trees…it’s actually the claw-like design of the last bone (the terminal phalanx for you anatomy aficionados) in their toes! They also have toe pads to aid in climbing and are typically lightweight as they are often gripping to leaves and small twigs.
More than a dozen treefrogs and allies live in Alabama including the Northern and Southern cricket frog, pine barrens treefrog, bird-voiced treefrog, Cope’s gray treefrog, green treefrog, pine woods treefrog, barking treefrog, squirrel treefrog, spring peeper, mountain chorus frog, upland chorus frog, southern chorus frog, ornate chorus frog, and the little grass frog.
Treefrogs locate and advertise for mates vocally. Some of the more interesting treefrog calls are the bird-voiced treefrog, Early spring in much of Alabama is filled with the trill sound of spring peepers. The cricket frog call is often described as “clicking two marbles together”. Early summer brings the call of the gray treefrog.
“True Frogs” – The Ranidae Family
This group of frogs has large powerful legs, most have webbed feet, and all lay their eggs in water. Many of this family are aquatic adults. Species include the American bullfrog, green frog, pig frog, river frog, pickerel frog, southern leopard frog, wood frog, crawfish frog, gopher frog, and the Mississippi gopher frog.
Some of these frogs are the most commonly recognized and widely distributed, especially the American bullfrog, green frog, leopard frog, and pickerel frog. The pickerel frog (above) is often confused with the leopard frog (below); however, you can distinguish the pickerel frog by its squarish spots and the bright yellow on the underside of its hind legs. The pickerel frog is the only poisonous frog native to the U.S. Its toxic skin secretions from its back can irritate human’s skin and be fatal to predators such as other frogs, snakes, or even small mammals.
The gopher frog is a federally endangered, medium-sized species primarily present in the Coastal Plain. The tadpoles are aquatic, but the adults are primarily terrestrial and often documented using gopher tortoise burrows in longleaf pine uplands. Gopher frogs require isolated, temporary wetlands as breeding sites that have become increasingly scare in the southeastern landscape. Gopher frogs have a distinctive “snoring” call that can be heard from over a quarter mile away.
Toads
All toads are technically frogs, but not all frogs are toads, and not all toads are “true toads”. Clear as mud? At a surface level, toads are often characterized by their dry and somewhat warty skin appearance as opposed to a frog’s smooth and sleek skin. A true toad has a Bidder’s organ (an organ near the kidney that regulates sex hormones). True toads also lack an upper row of teeth.
The true toads of Alabama are the American toad, Fowler’s toad, oak toad, southern toad, and Gulf Coast toad. Toad eggs are easily identifiable as they are produced in single strands and are typically dark brown to black in color. When threatened, toads will often take a defensive stance and excrete a toxic substance from the large gland behind their eyes known as the parotid gland, rendering them inedible to most predators.
The “not so true” toads include the eastern spadefoot toad, an exceptional digger with bright yellow eyes. The spadefoot toad is fossorial, meaning it spends the majority of its life underground. Heavy rains cause them to emerge and congregate for explosive breeding.
The eastern narrow-mouthed toad is also a small “not so true” toad whose shape resembles an over-inflated football. They have a skin fold across the back of their head that protects its eyes from ant bites. Narrow-mouthed toads are secretive critters that burrow in moist soil; however, they often give their location away during the breeding season with their long and unique call that sounds like a bleating lamb.
Do you have photos or videos of aquatic amphibians in Alabama? If so, share them with us using the AWW Photo/Video Submission form.