Spotted Salamander

Spotted Salamander
Conservation status
Least Concern (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Amphibia
Order:	Caudata
Family:	Ambystomatidae
Genus:	Ambystoma
Species:	A. maculatum
Binomial name
Ambystoma maculatum (Shaw, 1802)

The Spotted Salamander or Yellow-spotted Salamander (Ambystoma maculatum) is a mole salamander common in the eastern United States and Canada. The Spotted Salamander is the State amphibian of South Carolina. It has recently been found that its embryos have algae living inside them in a mutualistic relation.

Description

The spotted salamander is about 6–7.5 inches (15–19 cm) long. The spotted salamander's main color is black, but can sometimes be a blueish black, dark grey, or even dark brown. There are two rows of yellowish orange spots that run from the top of the head (near the eyes) to the tip of the tail. These rows are uneven. Interestingly, the spotted salamander's spots near the top of the head are more orange, while the spots on the rest of its body are more yellow. The underside of the spotted salamander is slate gray and pink.

Behavior

The spotted salamander usually makes its home around hardwood forest areas. They must have a pond as that is the only place they can lay eggs. A spotted salamander spends most of its time beneath ground level. It hides in moist areas under moss-covered logs or stones. These salamanders are secretive and will only exit their underground home on warm rainy nights in Spring, to breed and hunt. However, during the winter, they hibernate underneath ground level. Their defenses from predators include hiding in leaf litter or logs, autotomy, and a poison, which is not harmful to humans. In ponds or wetlands they hide near the muddy bottoms or hide underneath leaves at the bottom. They have the ability to drop their tails, to distract predators. If a predator of the spotted salamander manages to dismember a part of a leg, tail, or even parts of the brain/head, then it can grow back a new one, although this takes a massive amount of energy. The spotted salamander, like other salamanders show great regenerative abilities, even being able to regenerate limbs and parts of organs. They have large poison glands around the back and neck, which release a toxic white liquid. The larvae tend to occupy refuges in vegetation and lower their activity in the presence of predators (Brodman et al., 2002).

Life cycle

During the majority of the year, Spotted Salamanders live in the shelter of leaves or burrows in deciduous forests. However, when the temperature rises and there is a higher moisture level, the salamanders make their abrupt migration towards their annual breeding pond. In just one night, hundreds to thousands of salamanders may make the trip to their ponds for mating. Mates usually breed in ponds when it's raining in the spring. Females usually lay about 100 eggs that cling to the underwater plants. The eggs are round, clear, jelly-like clumps that are usually 2.5–4 inches (6.3–10 cm) long. Adults only stay in the water for a few days, then the eggs hatch in 1 to 2 months. Eggs of A. maculatum can have a symbiotic relationship with a green alga, Oophila amblystomatis. Jelly coating prevents the spotted salamander eggs from drying out, however 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). When the eggs hatch depends on the water temperatures. As larvae they are usually light brown or greenish-yellow. They have small dark spots and are born with external gills. In 2–4 months the larvae lose their gills, and become juvenile salamanders that leave the water. Spotted salamanders have been known to live up to 32 years (Flageole and Leclair, 1992) and normally return to the same vernal pool every year. These vernal pools are seasonal and will usually dry up during the late spring and stay dry until winter.

Diet

The spotted salamanders diet includes crickets, worms, insects, spiders, slugs, and millipedes. They are nocturnal and come out at night to hunt for food.

References

• Hammerson (2004). Ambystoma maculatum. 2006. IUCN Red List of Threatened Species. IUCN 2006. www.iucnredlist.org. Retrieved on 12 May 2006. Database entry includes a range map and a brief justification of why this species is of least concern.

External links

• Ambystoma maculatum at CalPhotos
• Ambystoma maculatum: Information at ADW
• Spotted Salamander at the Encyclopedia of Life
• Yellow-spotted Salamander (Ambystoma maculatum), Natural Resources Canada