Ambystoma laterale
Blue-spotted Salamander / Salamandre à points bleus
This salamander and the Jefferson Salamander are part of one of the most bizzare and
complex mysteries of amphibian biology. These two species are associated with hybrids,
usually female, with three sets of chromosomes (triploid) rather than the regular two
(diploid). Under certain circumstances, when hybrid females breed with male Blue-Spotted
or Jefferson Salamanders, sperm stimulates egg development but is not incorporated into
the genetic material of the egg. In such cases, the offspring is genetically identical
to the mother. Sometimes the sperm is incorporated into the egg, producing offpsring
with four sets of chromosomes (tetraploids). All these diploid, triploid and tetraploid
salamanders look quite similar. Biologists are still trying to understand this complicated
system.
Description
The Blue-spotted Salamander is bluish black with large blue flecks and grows to only
about 12 cm total length.
Confusing Species
The bluish colour of these species is very diagnostic. No other salamanders in eastern
Canada can be easily confused with the Jefferson complex.
Distribution
The Jefferson Salamander is
limited to southern Ontario, while the Blue-Spotted Salamander is more widespread,
from southern Manitoba to Nova Scotia and Labrador. Outside of Canada, they are found
only as far south as Virginia.
Habitat
These salamanders are found in a wide variety of woodland habitats: deciduous, coniferous
or mixed forests, as well as swamps. Breeding ponds can be permanent swamps or temporary
ponds, marshes or even roadside ditches.
Reproduction
Breeding occurs in the spring. Adults make their way to breeding ponds on warm rainy
nights. Females can lay up to 200 eggs either singly or in loose groups. The eggs hatch
in about a month's time and the larvae transform into salamanders in late summer.
Natural History
Outside of the breeding season, adults are completely terrestrial, often living
underground in burrows. Salamanders are carnivores eating a large variety of insects
and other invertebrates such as spiders and worms.
Conservation Concerns
The loss of wetlands and the destruction of forests threaten many salamanders. Many
salamanders are also killed on our roads every spring during their migration to the
breeding ponds. There is no evidence for decline in this species.
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