Twenty species of salamanders occur in Illinois. Salamanders, frogs and toads are the amphibians of our state.
Adult salamanders look like lizards in general body form but have four toes on each of their front feet and soft skin that is not covered by scales. Lizards have five toes on their front feet and scales on their skin. Some salamanders can be identified by the number of their toes or legs. The lesser siren, for example, lacks rear legs. The mudpuppy and four-toed salamander have four toes on each hind foot. All other Illinois salamanders have five toes per hind foot.
Even though most of our salamanders have lungs, the exchange of oxygen and carbon dioxide for respiration occurs mainly through their skin. The skin is kept moist for this function by mucus secreted by skin glands. Eight Illinois species of salamanders (family Plethodontidae) lack lungs and rely entirely on the skin and mouth lining for gas exchange. Larval salamanders and the adults of the lesser siren and mudpuppy have external gills.
Most Illinois salamander species have a two-part life cycle that includes the aquatic larval stage and the land-based adult stage. However, the mudpuppy and lesser siren spend their entire lives in water. Embryos of the red-backed salamander, zigzag salamander and northern slimy salamander undergo direct development and have no larval stage. Their eggs develop directly into tiny versions of the adults.
Females of most species lay their eggs in the spring, while the other species deposit eggs in autumn. The eggs are placed in a variety of wet or moist places, such as: woodland ponds; under rocks in streams; under mosses, logs, rocks or leaves along streams or ponds; inside rotting logs; in underground burrows; in rock crevices; or in caves. In some species, adults care for the developing embryos. The adult may stay with the eggs to keep them moist (if on land) by curling its body around them, protect them from predators and remove dead and decomposing eggs. In other species, the jellylike egg masses are attached to plant stems and twigs in fish-free pools and left with no parental care. Development from embryo into larval form takes from two weeks to three months, depending on the species.
The eastern newt is peculiar because it goes through three distinct stages during its life: larva, eft and adult. Adult newts live in lakes and ponds, where the female lays numerous tiny eggs wrapped individually in leaves of underwater plants. The embryo completes development in about two weeks and hatches into an aquatic larva that feeds and grows for a few months, then transforms into the eft. This juvenile newt lives on land for one to three years before returning to water to complete its transformation to the adult form.
Adult and juvenile mole salamanders (family Ambystomatidae) live in rotting logs and burrow in the forest floor. They emerge at night or during heavy rain to feed, and, in spring and autumn, to migrate to breeding ponds. The lungless salamanders (family Plethodontidae) are seldom active on the surface of the ground except at night, usually following rain. These animals live under moist leaves, logs and rocks, or in burrows. Juveniles and adults of some species are common around springs (cave salamander, four-toed salamander, long-tailed salamander), banks of small, rocky streams (dusky salamander, southern two-lined salamander, long-tailed salamander), and in forest floor litter (red-backed salamander, zigzag salamander, northern slimy salamander).
Salamanders are predators of earthworms, snails and invertebrates. A few salamanders also eat small vertebrates, including other salamanders. In turn, salamanders are eaten by a variety of fishes, small mammals, birds, snakes and invertebrates.
Because salamanders can be an important food source for many animals, they have defenses to help them avoid predators. Most salamanders produce sticky, distasteful or poisonous skin secretions that deter these predators. The slimy salamander can smear attackers with a sticky secretion, and the large tail of the tiger salamander can flip harmful secretions onto a predator's face. Skin secretions of the eastern newt induce vomiting in predators, which allows it to escape from a predator's digestive tract, if swallowed. The red-backed salamander may assume a coiled posture that protects its head while presenting its tail and unpleasant skin secretions. The dusky salamander can run swiftly to escape. The ability to lose its tail, either by constriction at the base of the tail (four-toed salamander) or by the long, easily-broken tail in other species provides a distraction for the predator while allowing the salamander to escape. Bright warning coloration, such as that of the long-tailed and cave salamanders, helps predators with color vision to associate the prey with the bad-tasting secretions and reminds predators to avoid these salamanders.
The primary conservation concerns for Illinois salamanders are habitat degradation, habitat fragmentation and habitat loss. Many populations have been eliminated, reduced or separated through loss of habitat. Draining wetlands, channelizing streams, removing temporary woodland ponds and sloughs, and clearing forests have all contributed to the decline of salamander populations in Illinois. Individuals of three Illinois species (hellbender, lesser siren, mudpuppy) are completely aquatic, and three-fourths of the remaining species have a gilled, aquatic, larval stage. These species require high-quality waters to live in at some point in their life cycles.
Family Ambystomatidae - The “mole” salamanders spend much of the year in the soil or under rocks or logs. They breed in spring. Most larvae transform into the adult form by late summer.
Jefferson salamander (Ambystoma jeffersonianum) – threatened in Illinois
blue-spotted salamander (Ambystoma laterale)
spotted salamander (Ambystoma maculatum)
marbled salamander (Ambystoma opacum)
silvery salamander (Ambystoma platineum) – endangered in Illinois
mole salamander (Ambystoma talpoideum)
small-mouthed salamander (Ambystoma texanum)
eastern tiger salamander (Ambystoma tigrinum)
Family Cryptobranchidae - These giant salamanders may only be found in Asia and the United States. They are true aquatic salamanders.
hellbender (Cryptobranchus alleganiensis) – endangered in Illinois
Family Plethodontidae - The lungless salamanders may be found in North and South America and Europe. They do not have lungs, and most breathe through the skin or through membranes in the mouth. There is always a groove present from each nostril to the upper lip. They may be found in moist habitats.
spotted dusky salamander (Desmognathus conanti) – endangered in Illinois
southern two-lined salamander (Eurycea cirrigera)
long-tailed salamander (Eurycea longicauda)
cave salamander (Eurycea lucifuga)
four-toed salamander (Hemidactylium scutatum) – threatened in Illinois
eastern red-backed salamander (Plethodon cinereus)
northern zigzag salamander (Plethodon dorsalis)
northern slimy salamander (Plethodon glutinosus)
Family Proteidae - The mudpuppies are found in Europe and North America. They are aquatic. They have permanent gills.
mudpuppy (Necturus maculosus) – threatened in Illinois
Family Salamandridae - The newts may be found in Europe, Asia, Africa and North America. Newts have rough skin.
eastern newt (Notophthalmus viridescens)
Family Sirenidae - The sirens are found only in North America. They are aquatic. The have external gills and only the front legs are present.
lesser siren (Siren intermedia)