Spotted Salamander Ambystoma maculatum

Adult male from Jefferson County

Identification

Adults are large, stocky salamanders with gray or black dorsal coloration and conspicuous yellow spots on the dorsum. Occasionally, these spots become orange near the head of the salamander. Ventral coloration is lighter than that of the dorsum. Adults of this species may reach total lengths of 8-9 in (20-22 cm) with some large females reaching 10 in.

Egg mass from Jefferson County
Adults in breeding pond in Jefferson County

Spotted Salamanders lay eggs in large, globular masses that are notably firmer than the egg masses of any other species in the genus. Occasionally, the egg masses become opaque and appear milky. Additionally, many Spotted Salamander eggs host a symbiotic algae that colors the embryo and eggs a green hue. Spotted Salamanders have pond-type larvae with tall tail fins and bushy external gills. Hatchlings and older larvae are dark and nondescript.

The Eastern Tiger Salamander (Ambystoma tigrinum) is the most likely species to be confused with the Spotted Salamander. However, it is much larger and has a proportionally larger head. The dorsal blotching pattern of Eastern Tiger Salamanders is much more irregular, not as bright a yellow, and often extends onto the belly.

Ecology and Conservation

Spotted Salamanders are a forest-dwelling species, preferring mature deciduous forests throughout their range. However, they can be found in more open-canopied situations when forests are nearby. They occur both in bottomland, floodplain habitat and well-drained upland forests. Larval Spotted Salamanders feed on small aquatic invertebrates while adults feed on a variety of terrestrial invertebrates.

Vernal pool from Jefferson County
Vernal pool from Jennings County

Reproduction occurs with heavy spring rains (typically in March), when these salamanders move in mass migrations to breeding ponds and reproduce en masse. While most Ambystoma prefer fishless breeding sites, Spotted Salamander will occasionally utilize larger, more permanent ponds when sufficient vegetative cover is present. Larvae metamorphose in the mid-early summer.

Other than habitat loss and fragmentation due to development, there are no particular threats to the Spotted Salamander in Indiana.

Distribution

Spotted Salamanders are widely distributed across much of the eastern United States, reaching as far south as Texas in the south-central part of the country and Florida in the East to as far north as Wisconsin in the Midwest and Maine in the East.

Spotted Salamanders are common throughout well-preserved forest in much of Indiana, but they are notably absent from the northwestern sand prairies.

Taxonomy

There are no recognized subspecies of the Spotted Salamander (Ambystoma maculatum). The Spotted Salamander belongs to the family Ambystomatidae, which is represented in Indiana by eight species (plus the unisexual Ambystoma)--the most of any state!

Literature Cited

Conant, R. and J. T . Collins. 1998. Reptiles and Amphibians of Eastern and Central North America. Third Edition, Expanded. Houghton Mifflin, New York, NY.

Minton, S. A. Jr. 2001. Amphibians and Reptiles of Indiana. Indiana Academy of Science, Indianapolis, IN .

Petranka, J. W. 1998. Salamanders of the United States and Canada. Smithsonian Institute Press, Washington D.C.

Distribution Map
Distribution map of Spotted Salamander (Ambystoma maculatum)
Photographs