Click for more images

Spotted Salamander

Ambystoma maculatum

Family: Ambystomatidae

COSEWIC status:
  • Not Assessed
SARA status:
  • No Status
IUCN status:
  • Least Concern

Description

Spotted Salamanders are heavy-bodied and can grow up to 25 cm in total length, although most individuals don’t exceed 15 cm. Adults are dark grey to black with distinct yellow spots on the back, sides, tail, head and legs, though it is possible to find adults that lack spotting. The belly and lower sides range from light to dark grey. Individuals have 11-13 costal groves. Aquatic larvae are generally a dull olive-green colour with feathery gills behind the head, legs (both front and back) and a tail fin.

Similar Species

Other species in the genus Ambystoma have a similar body shape and colour, but no other salamanders in Canada have distinct yellow spots. Aquatic larvae of Ambystomatidae salamanders are difficult to distinguish from one another.

Distribution

Click for larger image

Spotted Salamanders are found throughout eastern Canada from Northwestern Ontario to Nova Scotia and P.E.I. This species also occurs throughout most of the eastern United States, as far south as Louisiana.

Habitat

Spotted Salamanders inhabit deciduous and mixed forests, typically within close proximity to breeding habitats. Leaf litter and cover objects, such as logs and rocks, are important microhabitats where the salamanders forage and seek shelter. Individuals are sometimes found beneath wood piles and other debris in back yards. This species breeds in ephemeral woodland ponds (including ditches and other flooded areas) or permanent wetlands that are typically fish-free. Spotted Salamanders overwinter underground below the frost line in mammal burrows, root cavities and other underground crevices.

Biology

Spotted Salamanders migrate to breeding wetlands on rainy nights in early spring, often moving over snow banks and the icy edges of thawing ponds. Adults can migrate several hundred metres between overwintering and breeding sites. Each female will lay two to four large gelatinous masses containing 1–250 eggs each, which she attaches to submerged sticks or other vegetation. The eggs hatch into aquatic larvae after four to seven weeks, and the larvae transform into terrestrial juveniles by the end of summer. In Canada, males reach sexual maturity at three to six years of age, while females may not reach maturity until they are seven years old. Individuals may only breed every two or three years. Spotted Salamanders are long lived, and individuals may live over 30 years. After the breeding season, adults spend most of their time in underground burrows and cavities, making them difficult to find during the summer and fall. Adults and juveniles eat insects, spiders, worms and other terrestrial invertebrates, while larvae prey on immature aquatic insects and microcrustaceans.

Threats

The extensive conversion of natural habitat to agricultural and urban land uses has destroyed and fragmented much of this species’ habitat throughout the southern portion of its range in Canada, especially in Ontario. Ongoing habitat destruction, primarily from urbanization, cottage development and road construction, continues to cause localized population declines. Road mortality can be a significant threat to Ambystoma salamanders when roads bisect spring migration routes. Pollution, such as herbicides, agricultural effluent and road salt can be detrimental to salamanders since toxins are easily absorbed though their skin. Climate change and introduced pathogens pose potentially serious threats to Canadian salamanders.

Additional Information About This Species In Canada