If you’re a spotted salamander, Ambystoma maculatum, this is the night you’ve been waiting for. It’s time to polish those hot yellow spots and head on down to your local vernal pool. Odds are you’re gonna get lucky tonight.
Adult spotted salamanders are large, 6 to 10 inches, robust, brightly colored salamanders. They have a double row of bright yellow (some orange or orange-tinted) spots along their brown back. Their bellies are gray.
While these conspicuous critters are pretty common in forests below 3,000 feet across the region, they are seldom seen. This is because they are what biologists call fossorial animals, meaning they spend most of their life underground.
Spotted salamanders do a little burrowing of their own, but most of their time is spent in the underground tunnels of moles and shrews. Here they dine on earthworms, slugs, spiders, centipedes and various other insects. They are pretty sedentary animals and except for that one rainy night each year, may spend their entire life within a few square meters.
However, on that fateful February or March night when the rain starts falling and the temperature inches up, they put on their traveling shoes. They may travel as far as 500 meters to reach the vernal pool of their choice.
For most spotted salamanders, this is the pool they were hatched in. And if nothing happens to this vernal pool the salamander will use it for all of its relatively (up to 20 years) long life. There are even reports of spotted salamanders congregating in parking lots atop their breeding ponds that have been covered with asphalt.
Vernal pools are low-lying areas that usually fill with water from snowmelt and/or late winter rains. They are often bone dry in summer. The ephemeral nature of these vernal pools actually works in favor of breeding salamanders and frogs because it excludes fish that would dine on the larvae. However, the small size and transitory nature of these pools also make them very susceptible to development.
I don’t know if it’s because of the slime factor or the fact that everybody gets screwed, but these late night vernal pool gatherings are known as a “breeding congress.”
Lest we get too titillated, remember these are amphibians. If you are present at one of these salamander soirées, you may see a little petting – the male rubbing its chin over the female — and if it’s a really large gathering the salamanders will sometimes clump together in bowling-ball size masses.
When the female decides the time is right she will find spermataphores (sperm packets) that males have left attached to leaves and twigs in the water. She positions herself so as to insert the spermataphore in her cloaca where it will fertilize her eggs which she lays in batches of up to 400 in a jelly-like mass attached to sticks, leaves and/or submerged vegetation.
The eggs usually hatch in two to four weeks. The salamander tadpole takes another three months or so to metamorphose into a terrestrial salamander. It usually takes three to five years for a spotted salamander to become sexually mature.
Then, one late winter night, the rain will bring strange stirrings and it’ll be off to the salamander stomp.