The spotted salamander or yellow-spotted salamander (Ambystoma maculatum) is a mole salamander common in the eastern United States and Canada.
This salamander ranges from Nova Scotia, to Lake Superior, to southern Georgia and Texas.
First descried in 1802, the spotted salamander is the state amphibian of Ohio and South Carolina. All present-day salamander families are grouped together under the order Urodela.
With well-developed lungs, these amphibians are burrowers, spending most of their lives underground. Other members of the mole salamander family include the Jefferson’s and tiger salamander.
The spotted salamander (Ambystoma maculatum) is sometimes confused with the Jefferson’s salamander.
It has a dark body, like the Jefferson’s, but the spotted salamander has a chunkier body with two rows of bright yellow or gold spots on its sides.
Spotted salamanders are fossorial, meaning they spend most of their time underground. They rarely come above ground, except after a rain or for foraging and breeding.
Spotted salamanders have been known to live up to 30 years.
The spotted salamander usually makes its home in hardwood forest areas with vernal pools, which are necessary because they cannot breed in most permanent pools because the fish inhabiting the pools would eat the salamander eggs and larvae.
As juveniles, they spend most of their time under the leaf litter near the bottom of the pools where their eggs were laid. The larvae tend to occupy refuges in vegetation and lower their activity in the presence of predators.
Ambystoma maculatum has several methods of defense, including hiding in burrows or leaf litter, autotomy of the tail, and a toxic milky liquid it excretes when perturbed. The secretion comes from large poison glands around the back and neck. The spotted salamander, like other salamanders, shows great regenerative abilities.
The diet of larvae is dominated by zooplankton, but as they grow larger organisms such as isopods and amphipods are incorporated into their diet. The adult diet includes crickets, worms, insects, spiders, slugs, centipedes, and millipedes. Both larvae and adults are primarily nocturnal, coming out at night to hunt for food.
From March to May, when the temperature rises and the moisture level is high, the salamanders make their abrupt migration towards their annual breeding ponds.
In just one night, hundreds to thousands of salamanders may make the trip to their ponds for mating. It is known this species visits the same ponds year after year.
Mates usually breed at night, in ponds when it is raining in the spring. Females usually lay about 100 eggs in one clutch that cling to the underwater plants and form egg masses.
Adults only stay in the water for a few days, then the eggs hatch in one to two months.
Eggs of the Yellow-spotted salamander can have a symbiotic relationship with a green alga, Oophila amblystomatis.
The jelly coating prevents the eggs from drying out, but it inhibits oxygen diffusion (required for embryo development).
The Oophila alga photosynthesizes and produces oxygen in the jelly. The developing salamander thus metabolizes the oxygen, producing carbon dioxide (which then the alga consumes). Photosynthetic algae are present within the somatic and possibly the germ cells of the salamander.
When the eggs hatch depends on the water temperatures. Larvae hatch in four to seven weeks and another two to four months to metamorphose into land-living adults.
Spotted Salamander (Ambystoma maculatum) larvae are usually light brown or greenish-yellow. They have small dark spots and are born with external gills.
In two to four months, the larvae lose their gills, and become juvenile salamanders that leave the water.
These salamanders locate prey by smell and sight. Their vision is probably best for detecting motion in low light. Sense of smell is important in orienting spotted salamanders to their burrows and to their home pond, as are visual and tactile information. It is believed that home pond odors are preferred compared with foreign pond odors.
Salamander larvae are aggressive predators. They are generalists, eating whatever small animals they can catch. When they first hatch they feed mainly on small insects and branchiopod crustaceans like Daphnia and fairy shrimp.
As they get larger they take larger prey, including isopods, amphipods, larger insects, frog tadpoles, and other salamander larvae. In times of overcrowding, usually, when the vernal pools start to dry up, spotted salamander larvae may become cannibalistic and attack members of their own species.
The adult spotted salamander uses its sticky tongue to catch food. Their diet consists mainly of forest floor invertebrates, including earthworms, snails and slugs, millipedes, centipedes, spiders, and a wide variety of insects.
They sometimes also eat smaller salamanders, such as the red-backed salamander, Plethodon cinereus.
If a predator manages to dismember a part of a leg, tail, or even parts of the brain, head or organs, the salamander can grow back a new one, although this takes a massive amount of energy.
Oddly, the Spotted Salamander is the first known vertebrate to harness solar power for energy.
Use potting soil, coconut fiber, ground pine bark mulch or sphagnum moss that is free of fertilizers and chemicals. Good décor that allows for hiding includes bark slabs, driftwood, live plants, and logs. Normal household lighting is sufficient.
The best temperature is 50-70 degrees F. It should never exceed 75 degrees. Maintain humidity by daily misting with chemical-free water; however, never let the substrate become soaked.
These animals take their water differently than other animals do. They take it in through their skin and through their cloaca, which is a multipurpose opening. That is why the substrate must stay moist. The water should never have chemicals in it, including chlorine.
The spotted salamander is still a fairly common species, but its populations are particularly vulnerable because of their dependence on vernal pools for breeding. Acidic precipitation has a negative effect upon their embryos, and habitat destruction is a problem, especially as it isolates populations from each other. The species is rated “of Least Concern” by the IUCN, and is not listed by the U.S. Endangered Species Act, in the CITES appendices, or by the State of Michigan.