Meet the Axolotl, a Mexican salamander which looks like it comes straight from a cartoon or a Pokemon movie.
About the Axolotl
Although the axolotl is colloquially known as a “walking fish“, it is not a fish, but an amphibian. Axolotls are unusual among amphibians in that they reach adulthood without undergoing metamorphosis. Instead of developing lungs and taking to the land, adults remain aquatic and gilled. Axolotls can breathe through their gills, through their skin and with their lungs and regularly go to the water surface to get air, but do not come out of the water. Furthermore, they do not move much.
The axolotl originates from Lake Xochimilco underlying Mexico City, but today exists only in Lago de Chalco (Lake Chalco) in Mexico. There are different variants of Axolotls in different colors. In the wild, they are gray or brown. In captivity you see a lot of the cultured white variant. There are also variegated colored and gold-colored axolotl. In the wild an axolotl lives ten to twelve years, in captivity they can be about 25 years old.
As of 2010, wild axolotls were near extinction due to urbanization in Mexico City and consequent water pollution, as well as the introduction of invasive species such as tilapia and perch. They are currently listed by CITES as an endangered species and by IUCN as critically endangered in the wild, with a decreasing population.
Axolotls are used extensively in scientific research due to their ability to regenerate limbs.
Axolotls were also sold as food in Mexican markets and were a staple in the Aztec diet.
They also are popular pets.
Surveys in 1998, 2003 and 2008 found 6,000, 1,000 and 100 axolotls per square kilometer in its Lake Xochimilco habitat, respectively. A four-month-long search in 2013, however, turned up no surviving individuals in the wild. Just a month later, two wild ones were spotted in a network of canals leading from Xochimilco. The city is currently working on conserving axolotls by building “axolotl shelters” and conserving remaining and potential habitats for the salamanders. Read more ..
Axolotls in Captive Care
The axolotl is a popular exotic pet like its relative, the tiger salamander (Ambystoma tigerinum). Axolotls are part of the order Caudata/Urodela. They originate from the bottoms of two lakes in Mexico, but don’t be fooled – the lake was fed from a large glacier and remained cool throughout the seasons. Thus, axolotls require cooler water temperatures than most would believe. Axolotls have since been deemed an endangered species in the wild, and are now bred and thrive in captivity.
In a tank environment, they will never transform into the adult form, but will remain larvae. They are easy to care for and therefore make enjoyable pets. They have a lifespan of 10-15 years in aquariums if provided the right environment and care. (How to care for an Axolotl – Wiki How)
The Axolotl’s life cycle is a rare phenomenon as they live their entire lives in the larval stage, yet still, manage to breed. “It is believed that they have evolved to be this way due to low levels of iodine in their native waters. Experiments have been done and Axolotls will metamorphose when exposed to iodine, and they develop into salamanders that look similar to the closely related Tiger Salamander.
Axolotls have excellent regenerative abilities and can regrow limbs, tails and even heart and brain cells at an outstanding rate. This has made them a popular focus in scientific research.” [theamphibian.co.uk]
Colorations, size and lifespan
Main Morphs (Colourations): There are several different color variations [morphs] in Axolotls that occur in captivity.
Wild type: Mottled green with shiny eyes and dark purple gills.
Albino: White/very light pink with clear pink/red eyes and bright pink/red gills.
Melaniod: Black/dark gray with black eyes and dark gills.
Leusistic: White/pink with dark eyes, bright red/pink gills. May or may not develop freckles.
Golden Albino: Golden/yellow with shiny patches, pink/fire orange eyes, bright red/pink gills.
Copper: Copper/olive with dark eyes, bright red/pink gills.
Other morphs: There are other morphs that are considered rare and unique, these morphs consist of Piebald, Golden Non Albino, Chimaerism.
GFP: (Green fluorescent protein) Is a recessive gene that can be contained in any morph. This means that axolotls who carry the GFP gene can glow green under black / blue light.
Size: Axolotls can grow up to 25-30cm (10 – 12 inches). Dwarves at around 7 inches.
Life Span: Axolotls can live up to 15 years with appropriate care, but generally clock out at about 10 years.
How to care for an Axolotl
Axolotls are carnivore and eat meat. An axolotl has no sharp teeth, only kind small stumps. They can not bite or tear with it, but hold it with slippery tassels. The axolotl swallows its prey all at once and can only eat preys that fit all in. You can feed an axolotl with rain worms, dead baby mice, small fishes, mosquito larvae, cat food and water insects.
Feed your axolotl a proper diet. You can buy night-crawlers and frozen bloodworms at a local pet store. These should be the staple of your axolotl’s diet. You can also provide frozen shrimp and bits of chicken for a treat. In general, avoid live food.
In captivity, axolotls eat a variety of readily available foods, including trout and salmon pellets, frozen or live bloodworms, earthworms, and waxworms. Axolotls can also eat feeder fish, but care should be taken as fish may contain parasites.
Axolotls eat dead or live food but often eat it when they see their prey moving. If you give dead food, it is often necessary to wobble it back and forth, to imitate a moving prey. Do not give them wild prey because these can contribute to diseases. Feed them food from the animal store or breed food yourself.
Axolotls must be fed once a day, or every other day for half an hour. Provide the axolotl with as much food as it can eat in a half hour time frame. A rain worm or similar amount of other food is enough for one day. Axolotls smaller than two centimeters can only be fed with very small live food.
Setting up a tank. A 10-gallon tank can work for a single axolotl. However, bigger is generally better when it comes to an axolotl. Opt for the biggest tank you can fit into your home. A 20-gallon tank is a good size for an axolotl
- Fill the aquarium with water completely, the way you would fill it for fish. Tap water is safe to use.
- You should keep a lid on the aquarium at all times. Axolotls will sometimes jump out of their tanks.
As for all poikilothermic organisms, lower temperatures result in slower metabolism and a very unhealthily reduced appetite. Temperatures at approximately 16 °C (61 °F) to 18 °C (64 °F) are suggested for captive axolotls to ensure sufficient food intake; stress resulting from more than a day’s exposure to lower temperatures may quickly lead to disease and death, and temperatures higher than 24 °C (75 °F) may lead to metabolic rate increase, also causing stress and eventually death. Chlorine, commonly added to tapwater, is harmful to axolotls. A single axolotl typically requires a 40-litre (11-US-gallon) tank with a water depth of at least 15 cm (6 in). Axolotls spend the majority of the time at the bottom of the tank. Salts, such as Holtfreter’s solution, are usually added to the water to prevent infection.
Provide substrate. Substrate is material that lines the bottom of an aquarium. The bottom of an axolotl tank should be lined with large fish tank pebbles (larger than the axolotl’s head) or fine sand (fine grain sand being the ideal substrate). Do not use small pellets or rough sand (such as blasting sand). An axolotl may accidentally ingest such substances.
If gravel (common in aquarium use) is used, it is recommended that it consist of smooth particles of a size small enough to pass through the digestive tract. One guide to axolotl care for laboratories notes that bowel obstructions are a common cause of death, and recommends that no items with a diameter below 3 cm should be available to the animal. There is some evidence that axolotls might seek out appropriately-sized gravel for use as gastroliths based on experiments conducted at the University of Manitoba axolotl colony.
Install a filter. You need a filtration system in place when caring for an axolotl. An external canister filer works best, which you can purchase at a local pet store.
- Any filter you install should have an spray bar or other outlet to control water flow. While axolotl’s need some water flow, too much can cause them to stop eating.
Change the water regularly. Once a week, remove 50 to 60% of the water from the tank. Then, replace it with fresh water. Tap water is safe to use if you have a filtration system in place.
Set up the right lighting. You do need to provide lighting for an axolotl the same way you would light a fish tank. Bright lighting may actually cause an axolotl to feel distressed, so opt for a plant lighting if you add a light at all. Axolotls do not need a lot of light to thrive, so lighting is usually so you can see the animal.
- Minimize how often you keep the light on. Lights can generate excess heat, which can be bad for an axolotl.
Separate young and old axolotls. If your axolotls breed, you should remove the babies from the tank using a net and place them in a separate aquarium. Older axolotls may prey on younger ones, so it’s not safe to keep axolotls of different ages in a tank together.
Do not place other animals in an axolotl tank. Axolotl are best kept in their own tank, but occasionally can do well with another axolotl of a similar size and age. However, they will prey on other types of fish or marine life. In general, an axolotl tank should only contain axolotls.
Refrain from handling axolotls. Axolotls are not people-friendly pets. They do not need human contact to be happy and, in fact, this may stress them out. Only handle an axolotl when necessary, such as removing babies from a tank. Axolotl also may nip if handled.
- Axolotl at the Encyclopedia of Life
- Ambystomatidae at DMOZ
- Follow the Eggs, Hatchlings and Juveniles
- Mating Dance and Laying Eggs
- Follow the Eggs and Hatchlings (2nd Batch)
- Indiana U Axolotl Colony
- University of KY Axolotl Colony
- Mystical amphibian venerated by Aztecs nears extinction
- “Axolotl“. Encyclopædia Britannica. 20 (11th ed.). 1911. p. 63.
- Folklore The Tao of Axolotl – thetolteciching.com
- Ambystoma mexicanum IUCN Red List of Threatened Species.