Axolotls

COMMON NAME: Axolotl

SCIENTIFIC NAME: Ambystoma mexicanum (also A. talpordeum and A. subsalsum)

DISTRIBUTION: Mexico

HABITAT: Mountain lakes

ADULT SIZE: 30 cm (12 in)

GENERAL: Axolotls are the king-size tadpoles of a MexicanSalamander. The odd thing isthat although they areimmature, they breed freely.This condition, which is knownas neoteny, is due to a lack ofthyroxine. In the wild it sometimes happens that the waters inwhich the Axolotls live, dry up and the beds of the lakes becomebaked solid by the sun, but the Axolotls, instead of dying as onemight expect, lose their gills and become adult salamanders.Generally these animals are a dark greyish black, but there isanother form, that is frequently kept in captivity, which is almostcompletely white apart from the bright red, feathery gills.

FOOD: In the wild Axolotls take tadpoles, insect larvae and fish. Incaptivity they eat earthworms, maggots and many kinds of otherlive food. Feed only on alternate days as digestion is slow.

HOUSING: The only way to keep Axolotls is in an aquarium. Alarge tank can house several, but they are better kept individuallyin tanks measuring 60 X 30 X 38 cm (24 X 12 X 15 in) as in acommunity they tend to bite off each other's feet and gills,although these usually regenerate eventually. A thick layer ofgravel should be placed in the bottom and the tank filled withclean water which must be chlorine free, so if you are using tapwater, do leave it to stand for a couple of days before introducingan Axolotl. A water temperature of not less than 20°C (68T) is essential. The tank can contain water plants and rocks.

BREEDING: Adult females are plumper than males and the latterhave an enlarged cloaca. Though Axolotls will breed throughoutthe year, the spring is generally the best time and to induce breeding lower the water temperature slightly and introduce amale into a female's tank. The male will court the female with adance that involves much tail swishing and after mating a collec-tion of eggs will be deposited on stones and the leaves of plants.They should be removed to a separate tank as adult Axolotls willeat their babies. In the wild around 400 eggs are laid at a time,and even in captivity Axolotls produce large quantities which, in awater temperature of 21°C (79T), will hatch in two to three weeks.The young animals should be fed with suitably sized livefood suchas Daphnia, mosquito larvae, Brine Shrimp and tubifex.