An adult Spotted Salamander. |
Spotted Salamanders (Ambystoma maculatum) are our largest local salamanders, with some reaching up to 10" in length. They are dark and usually have two irregular rows of light colored spots. They are "mole salamanders" spending the majority of their adult lives underground in other animals' burrows, but need to come out at least once a year in order to breed in their natal vernal pools. These temporary ponds are the only location many vernal pool wildlife species such these have a chance to survive. This is due to the relative lack of predators, specially fish, which of course could not survive in a wetland that exists only temporarily. They emerge to take advantage of the ephemeral ponds at the first relatively warm rains of spring, often in early March around our area.
Males leave sperm packets called spermataphores as evidence they were trying to find mates in the vernal pools. |
White spermatophores (sperm packets) laid by the males during the night along the pond bottom often signal their presence even before any egg masses are laid. These masses contain 200 or so eggs a piece, are normally attached to a twig or other aquatic vegetation, and are firm holding their shape if removed from the water (unlike wood frog eggs). The egg masses themselves start off either white or clear before often developing a symbiotic algal covering (Oophila amblystomatis) which is particular to this genus of salamanders.
Clear egg mass with developing larvae |
The gilled larvae that emerge develop quickly, feeding off of other vernal pool species, even each other, as they race to metamorphose into adults and leave the pond before it dries out. Some years this can number many, others none. Luckily the salamanders are long-lived (one is known to have lived 27 years) so that enough good years make up for the bad years, as long as their woodland habitats and vernal pools both continue to exist.
Spotted Salamander larvae have external gills that appear almost like manes. |
Many naturalists and other nature lovers eagerly await the occasional "big night" when vernal pools species such as wood frogs and spotted salamanders emerge en masse and migrate to their natal pools. Having been lucky enough to have seen this natural spectacle, I can tell you they are well worth waiting for, a true sign of the new birth of spring.
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