Axolotl Facts: Regeneration, Gills & Habitat

Axolotls are extraordinary aquatic salamanders native to Mexico. These fascinating creatures remain in their larval form throughout their entire lives, a condition called neoteny.

Remarkable Regeneration Abilities

Axolotls possess the most advanced regeneration capabilities of any vertebrate animal. They can regrow entire limbs, tails, parts of their heart, brain tissue, spinal cord, and even portions of their eyes. The regeneration process is so precise that the new tissue is virtually identical to the original. When an axolotl loses a limb, cells at the wound site form a structure called a blastema.

External Gills and Breathing

The most distinctive feature of axolotls is their feathery external gills that protrude from the sides of their heads. These gills appear as three branches on each side, creating a frilly crown like appearance. The gills are filled with blood vessels that extract oxygen from water. Axolotls can regenerate damaged gills just like their other body parts.

Colors and Genetics

Wild type axolotls display dark coloration with spots, providing camouflage against predators. However, selective breeding has produced numerous color varieties. Leucistic axolotls are pale pink or white with black eyes and dark pink gills. Albino axolotls lack all pigment, appearing white or golden with pink or red eyes.

Habitat and Wild Population

Axolotls are endemic to Lake Xochimilco and its canal system near Mexico City. This is the only place they naturally occur in the wild. Historically, they also inhabited Lake Chalco, but that lake was drained in the 1970s. Recent surveys estimate fewer than 1,000 individuals remain in the wild.

Diet and Hunting Behavior

Axolotls are carnivorous predators that hunt using sight and smell. In the wild, they eat worms, insects, small fish, and crustaceans. They are opportunistic feeders that consume almost any protein source they can swallow. Axolotls have small teeth but use them only for gripping, not chewing.

Reproduction and Development

Axolotls reach sexual maturity at 12 to 18 months when they are about 6 inches long. Breeding is triggered by temperature and day length changes. Females lay 100 to 300 eggs individually on plants or decorations. The eggs hatch in 14 to 21 days depending on water temperature.