AXOLOTL   Ambystoma mexicanum

So, what is an Axolotl?

Quite possibly one of nature’s most interesting creatures, the Axolotl is a Salamander from Mexico.

Axolotls are classed as Amphibia and members of the family Ambystomidae.

The distribution is small, naturally being found in Lake Xochimilco, 20km Southwest of Mexico City.

An incredible feature of these salamanders is that they are neotenic, simply put, they keep juvenile characteristics right into adulthood (or never actually become true adults) yet are still able to breed.

Remaining completely aquatic and not metamorphosing into a ‘normal’ salamander has proved an evolutionary advantage to the Axolotl.

Physically, as they mature, lungs develop, yet they never lose their feathery external gills, and the body does not change to suit a more terrestrial environment. it is almost like the common frog remaining as a tadpole right through its adult life.

Another remarkable property of the axolotl is the ability to regenerate parts of the body without scar tissue. Not only limbs are able to regenerate, but also the heart, lungs, jaws and even large parts of the brain! It is little wonder that they have become the go to creature to study in the biological laboratory.

Recent work is discovering that they have a natural resistance to many forms of cancer.

Keeping Axolotls in the home.

Those kept in the home will be captive bred.

Fortunately, keeping axolotls in the home is relatively simple as they are hardy and place few demands on the owner, however, this hardiness should never be viewed as a path towards poor animal management. They are bright and feel pain so the owner should be aware of their responsibilities towards keeping them.

There is also a higher reason for keeping them correctly, in the wild, Axolotls are not doing well. Last assessed in 2019, it was found that the wild population trend is decreasing and estimated to consist of only around 50-1000 adult individuals!

The IUCN status for the Axolotl is CRITICALLY ENDANGERED

The axolotl in captivity may live well over 10 years and reach a length of 45cm! So proper housing is required.

It is best to begin with slightly smaller quarters for juveniles and as they grow, their enclosure increased in sized also. The main reason is so they can find their food with ease.

For example, a par of 8-12cm Axolotls can easily be maintained in an aquarium of 3 feet in length, if the water is filtered sufficiently. A pair of 30cm or more should ideally be kept in an aquarium of no less than 4 feet of length.

Axolotl environment and water parameters

Being naturally curious, their home should be furnished with many smooth stones and artificial plants. The purpose is to prevent the animals becoming bored. They spend a large amount of time nosing around the aquarium looking for food or seeking a good place to snooze. In fact, there should always be a cave available for axolotls to find refuge in. This has an interesting side effect, if they have a quiet resting place they can retreat to, then they are more likely to feel confident and spend more time on show.

There is an urban myth about substrate. Many people believe that axolotls cannot be kept on gravel, for fear that they will ingest the gravel, and this will become lodged in their digestive system. This is simply untrue! Axolotls are more than capable of spitting out what they do not wish to eat, and there has been many studies that show any ingested gravel was done on purpose to help positively with digestion. Think of chickens keeping grit in their crops to help with grinding up the hard seeds they eat. With over 60 years combined experience keeping thousands of axolotls, we never had a single instance of ‘gravel impaction’.

Axolotls do not have eyelids. Lighting of the aquarium therefore should be at low levels, and always turn on room lights before turning on the aquarium lights. Many an axolotl nose has been damaged by turning the lights on too suddenly and sending the creature into a panic!

Axolotls are very resistant to disease except when kept in water of poor quality. They are messy feeders and produce a large amount of waste. However, they also do not like a large flow of water over them. It is far better to purchase a large water filter than can be turned down. That way there is sufficient filter media, and potential nitrifying bacteria to cope with the waste being produced, but the returned water is not blowing the axolotls around the aquarium. Medium to large external filters are an excellent choice, as is a sump system.

It should be noted that axolotls are cold water species, indeed warm water will stress them greatly. Beneficial bacteria that live in the filter and break down waste are slow at reproducing and sluggish at colder temperatures. Any filter must therefore have as much biological filter media as possible to encourage these bacteria. Filling the filter with ceramic noodles is a good choice.

Normally filters contain three types of filter media:

Mechanical media, such as filter wool

Chemical media, such as activated carbon

Biological media, such as fine sponges or noodles for the bacteria to colonise.

For the axolotl aquarium, the final stage, or biological media should be the major part of any filter.

Sadly, small internal filters tend to only have a small sponge, which can be regarded as mechanical filtration, and over time will be colonised with nitrifying bacteria. This type of filter media will seldom be large enough to hold enough bacteria. Also, the flow is often too high for an axolotl aquarium.

Under gravel biological filtration works fine, if the gravel is siphoned and cleaned periodically.

Establishing a routine of a 25% water change per fortnight is good practice. This will keep excessive levels of nitrate down and replenish lost minerals from the aquarium.

Feeding

Feeding axolotls could not be simpler.

If it’s meaty, non-processed and not fatty, they will eat it! All axolotls can live happily their entire lives without being offered live food stuffs. Defrosted foods are a great choice. Small axolotls do just fine on bloodworms and occasionally broken up prawn. Adult axolotls relish whole prawn taken out of their shells, chopped squid, and there are plenty of dried foods now available. There are now however, specialist Axolotl feeds, developed specifically for an Axolotls needs. NT Labs produce a variety of Axolotl products, from Juvenile and Adult feeding pellets, to water conditioner and medicinal treatments.  We fully endorse all of NT Labs Axolotl products!