Axolotl: Facts, Habitat and why the Peter Pan of Salamanders is Endangered

Axolotls are considered to be one of the greatest creatures of nature, hence their nickname of being the Peter Pan of the salamanders because of their capacity to never grow old. This fascinating Mexican salamander has a certain appeal to the scientific, pet keeping and conservation communities alike but few individuals really know about the amazing biology of this remarkable salamander species as well as the perilous conservation status of this amphibian.

Mexican axolotl detail of the external gill-like fluffy gills used to breathe under water

In comparison with other vertebrates on this planet, the axolotl has supernatural-like abilities that would make even the comic-book heroes jealous. These aquatic wonders are able to naturally replace entire limbs, heal broken hearts and even replace parts of its brain. Nevertheless, their abilities of regeneration are impressive; nevertheless, in the wild, there are less than 1,000 axolotl individuals, who are now looking at a particularly sad fate.

What is an axolotl? Knowing More about This Unique Amphibian

The axolotl (scientific name Ambystoma mexicanum) is an interesting biological phenomenon referred to as neoteny in which an organism does not undergo maturity despite being in its adult stage. Most salamanders develop through metamorphosis, aquatic larvae to terrestrial adults, but axolotls follow another evolutionary pattern entirely, and continue to live as aquatic gilled adults their whole lives.

This Mexican salamander falls under family Ambystomatidae and is closely related to tiger salamander. But the question is what is an axolotl, and you will know this better when we take the details on their distinctive features that make them an axolotl and not any other amphibian. One of the more unique features regarding its appearance is the feathery, external gills, airless eyes, and a permanent look approximating that of a smile.

Leucistic axolotl with unique white body and pink external gills in the captive environment

The azolotl derived its namesake Old Nahuatl word including the water character (atl) and the god of fire and death (Xolotl). This origin of the word fits the great cultural role the creatures played in pre-Hispanic Mexico, having been worshipped as living symbols of divine change and renewal.

Physical properties and looks

The axolotls have a very different look that is easily distinguishable amongst aquatic animals. The size of these amphibians is usually 6 to 12 inches but can also get as much as 18 inches. Adult axolotls are typically between 2 to 8 ounces although weighed up to 10 ounces in captivity.

The most prominent thing about any axolotl is the external gills. These are wispy growths on either side of the head, which look like ferns in a river, moving easily as its movements. The main breathing organ is the gills that enable the axolotls to mask out oxygen in the water by means of special capillaries.

In the wild, the coloration of axolotl is already hugely different when compared to their laboratory counterparts. Wild axolotls normally have dark brown to black colors with mottling patterns that are very useful within the native environment. Departing form that, captive-bred axolotls have many color variations, such as leucistic (white with pink gills), albino, golden, and even blue morphs.

Leucistic axolotl with sign of its pale pink color and brightly colored external gink in a green plant environment in water

The head of the axolotl is disproportionally large in comparison to its body and has small, lidless black eyes and a wide mouth which gives them a perpetual smile. Their legs are fairly small yet serviceable with four toes on the front legs and five on the back legs all coupled with webbed feet that helps them in swimming.

The Axolotl and Its Regeneration, Explained Scientifically

There are few areas of axolotl biology as studied as their ability to regenerate. These salamanders are able to regenerate just about any part of their body, whole limbs, pieces of their heart, the spinal cord, and even brain. Their regenerative ability is much higher than that of any other vertebrate making axolotls a leading research topic in regenerative medicine.

The process of regeneration starts immediately after the wound is already injured and cells consisting of wound epidermis start forming over the amputation area within hours. These cells multiply quickly over the next several days to form a structure known as a blastema – an undifferentiated mass of cells which is able to develop into any type of tissue necessary to regenerate it.

Axolotl stump regeneration depends on an elaborate molecular pathway that incorporates retinoic acid, a derivation of vitamin A which plays a significant role as a signaling agent. Recent studies have shown that more effective regeneration is measured not by increasing the production of retinoic acid but by destroying it by way of certain enzymes. This forms specific gradients that direct the cells on what structures to form and where to put it.

An axolotl in a transparent container as is in figures demonstrating its surface gills and particularities
The regeneration schedule can change depending on the age of an axolotl, and the level of damage. Juvenile axolotls have the capability of regenerating a complete limb within 40 to 50 days or the complete loss of a limb may take three months in older specimens. Bizarrely axolotls can grow themselves new limbs even after the original limb has healed up, and sometimes it grows extra limbs, leaving them with more limbs than before.

Where Does an Axolotl Live and Where Is It Native?

The axolotl only inhabits an extremely small geographic location as well – the lakes of Xochimilco within the Valley of Mexico region of modern-day southern Mexico City. This is one of the smallest natural areas of any vertebrate species, and makes conservation of axolotl, particularly difficult.

In past times, axolotls lived in a large system of networks of linked lakes and wetlands in the Mexican Central Valley, including the long-extinct Lake Chalco. These freshwater lakes of high altitude offered the ideal habitat to axolotls, as the temperatures were cool, there was plenty of vegetation in water and little flow of water.

Beautifully painted trajinera boats on the canals of Lake Xochimilco which is also home to an endangered species of axolotl salamander

The Xochimilco ecosystem is a very distinctive wetland because it comprises an intertwining system of canals, small lakes and man made islands known as chinampas. These chinampas were traditionally constructed by the ancient Aztecs to produce crops, but have remained an important aspect of the axolotl conservation scheme up to the current day. The canals have relatively constant water levels and provide much-needed habitat structure to axolotls, and other native species.

In habitation, water quality in an axolotl needs certain conditions to survive. Axolotls grow well at cool temperature of the water (14-20 o C or 57-68 o F), adequate oxygenation, and minimal pollution. The geography of the natural habitat has abundant growth of aquatic plants, soft muddy bottoms to dig into and different depth areas to feed and shelter.

Processing, Diet, and Feeding Behavior

The axolotls are obligatory carnivores with diversified diet expressed by the opportunities of the strategy of prices. In the wild, the axolotl eats a diverse diet made up of insects, insect larva, fish, worms, crustaceans and mollusks. Through this, their feeding behavior responds to the sources of the available food, and this makes them extremely successful predators in their watery habitat.

The axolotl feeding is based on strong suction instead of the ability to chew on foods. These amphibians have small and primitive teeth whose design is used to grip instead of tearing more prey. In hunting, the axolotls open their mouth quickly and thus establishing a vacuum that sucks the prey in their mouth together with the water and in some instances, the substrate materials.

Axolotl hunting is mostly done at night during the time the animals come out of their hiding places in the form of aquatic vegetation. Poor eyesight means they mostly rely on their sense of smell as well as their lateral line system to sense any movement of prey item as well as chemical signals in the water. This type of sensory adaptation enables axolotls to effectively go hunting in the dark waters in which they naturally live.

Captive axolotl diets may consist of earthworms, bloodworms, brine shrimp and specially raised pellets specifically available to aquatic amphibians. Nourishing captive axolotls sustenance is of utmost importance to center on variety and proper-sized food items that do not lead to choking or digestive problems.

Life Cycle Lifespan

The axolotls are extremely long-lived amphibians and can live 10 to 15 years in wild and captivity. Individuals in captive and well-cared environments are reported to survive beyond the age of 20 years, although this is at the maximum end of their natural living span.

The reproduction process of the axolotl starts when the organisms mature sexually between 6 and 12 months of age. Breeding of the cow nosed ray usually happens during the month of March – June when there are cooler temperatures in the water and the change of season in their natural habitat. The courtship in axolotl is an elaborate ritual process and during this process the males and females have a type of waltz where the males and females rub and slide against each other across a spectrum resembling a circle and then the male deposits a sperm packet and the female retrieves it.

Female axolotls spawn 200 to more than 1,000 eggs at one time. These are laid singly on aquatic plants or other substrate sources where they grow to maturity after a period of about 2 to 3 weeks. Axolotl larvae hatch as miniatures of adults and have external gills and the same body plan as they will use throughout their lives.

Axolotl do not experience metamorphosis unlike most of the amphibians. Young axolotls merely become larger and retain their characteristics as a larva: the presence of external gills, an aquatic existence, and a fish-like structure of the tail in the form of so-called fins. This neotenous development strategy is one of the most peculiar animal life cycle.

The Cultural Heritage of Axolotls in the Mexican Heritage

The axolotl is a very important part of Mexican culture, as the animal dates back as early as pre-Hispanic people who considered them holy. The Aztecs believed axolotls were physical embodiments of Xolotl, a god with a canine-like head, god of fire, lightning and the dead who led the dead to the underworld.

Painting of the Aztec god Xolotl, to whom the axolotl was related in Aztec beliefs

As Aztec mythology goes, attempting to evade destiny when the gods decided to sacrifice themselves to put the newly created sun in motion, Xolotl tried to do so through a round of transformations. According to legend, Xolotl took on the form of a corn plant, then a maguey plant and finally an axolotl so he could go and live in the water. This final alteration lends to the name of the axolotl, and gives them their mythological relation to the idea of transformation and, regeneration, and life and death.

The ancient Mexicans regarded axolotls as sources of regeneration and renewal, scholarship is able to trace the long part of modern science with the biological processes of understanding that these creatures were immensely capable of healing. This cultural respect percolated to functional activities whereby the presence of axolotls was utilized as food and medicine within Aztec community.

The axolotl is today a significant cultural symbol of Mexico reflecting both cultural identity or Mexican identity as well as environment. Axolotl are now used as a symbol of biodiversity and endangered species in contemporary Mexico by the artists, designers and conservationists of the time.

What Causes Axolotls to be Endangered?

The endangered status of the axolotl is among the greatest and urgent issues that conservation biology is facing today as with the wild populations putting a 99 percent loss of population during the last 20 years. It is estimated there are now less than 1,000 in the wild and some surveys have reported finding zero.

There are a number of interconnected threats that have led to axolotls nearly going extinct. Habitat destruction ranks as the main cause with habitat destruction as the metropolitan city of Mexico swallowed tremendous amount of the original lake system. The once expansive wetlands that made up thousands of acres that were all connected now are mere islands of their own in the form of canals and the salamanders are now fragmented.

Water pollution is an equally detrimental risk to the survival of the all the axolotls. Due to the contamination of degrading water quality, urban runancer, untreated sewerage, and agricultural chemicals have deteriorated the water quality in Xochimilco. Not only are these pollutants harmful to the axolotls, but they also disrupt their food webs and breeding cycles and produce cascade effects across many levels of the ecosystem.

There has been an overall change in ecological balance of the axolotl habitat through invasion species introduction. Exotic fish such as carp, tilapia and rainbow trout will compete with axolotls, predette on their egg and young. These invasive predators have no natural reproductive checks and they have spread all over Xochimilco.

Climate change adds to the current threats because of the increase in water temperature, and changes in precipitations. Axolotls are ectothermic and need cool water temperatures to thrive and exposure to elevated temperatures decreases their reproductive success and fitness.

Protection and a Future of Recovery

Amid the pessimistic situation wild axolotls find themselves in, there is a real hope to achieve species recovery thanks to new conservation interventions. The Chinampa Refugio Project, a project created by researchers at Mexico s National Autonomous University (UNAM), is regarded as the most feasible plan of implementing the conservation of axolotls; in the sense that they incorporate the ancient farming techniques with modern conservation techniques.

This innovative program gets directly involved with local farmers to restore chinampas across Xochimilco and establish some safe havens for axolotls. This project takes place in plants made of volcanic rocks and native plants located around the place of farming and, as such, cleans the contaminated water and prevents any of the invasive species getting into the canals and carrying the disease.

Relaxing canals Lake Xochimilco and similar chinampas gardens and vegetation, native to axolotl in Mexico
Significant success in habitat improvement has been evidenced with the use of the biofilter system. Improvement in the quality of water is noted such as the decrease in the amount of pollutants in the water, and more oxygen in the water, and recovery of the native fish species due to degraded waters. These created habitats enable axolotls to have access to clean water and a variety of food webs to keep sustaining them and reproducing.

Captive breeding schemes fill the gap of habitat rehabilitation in sustaining genetic diversity and individual supply of animals to supplement reintroduction. Recent releases of captive-bred axolotlsinto rehabilitated environments have been successful, with the released animals being able to live in their habitats and adaptto them.

The adoptaxolotl campaign promoted by UNAM is a campaign that involves the adoption of the axolotl by people in different parts of the globe. The novel source of funding generated hundreds and thousands of pesos to fund research, habitat restoration, and community education programs.

The Axolotls in Scientific Studies and in Medicine
The axolotls have become so vital as study subjects in the field of regenerative biology and in the development of therapeutic uses. They have distinctive regenerative capabilities that can provide us with answers to some of the pivotal questions about stem cells and tissue engineering as well the processes that govern organ development.

There are collections of axolotl in research institutions around the world which are kept specifically as a research resource to regnerative medicine. The ability of the axolotl to repair the brain, spinal cord and limbs has now been successfully examined at the genomic level with scientists successfully mapping parts of the axolotl genome identifying important genes that cause them to regenerate and comparing them with the same genes in humans and other mammals.

Recent discoveries in axolotls have shown the actual molecular pathways that direct limb regeneration. Learning how “axolotls” form and sustain gradients of signaling molecules to create regenerative responses is a potential blueprint to initiate similar regenerative effects in human tissues.

The advances of genetic manipulation methods have made a tremendous change on how Axolotls can be researched especially the use of CRISPR gene editing. Scientists are now able to select this or that gene and switch it on or off in order to understand its role in regeneration, thus paving a new development path in therapeutic field.

The current investigations are aimed at establishing the minimum requirements (molecular and cellular) required to induce blastema formation – the holy grail of regenerative biology. Success in this area can result in effective therapies applying to spinal cord injuries, loss of limbs and loss of organs organs that have no successful treatments at the present.

Ethical Considerations and Pet Care Requirements of Axolotls as Pets

In recent years, the popularity of axolotls as exotic pets has exploded due to online popularity and these surreal creatures unique looks. Nevertheless, all potential axolotl pet owners need to learn about the moral issues and the significant costs of caring about these delicate creatures.

Ethicalaxolotl keeping includes acquiring the animals only through established captive breeding programmes, and not wild-sourced animals. Legitimate breeders usually provide morphs like leucistic, which are not the same as the color of the wild animal, which are good indicators that an animal is bred in captivity.

The needs of axolotl care are found in the form of specialized aquatic systems with highly monitored water. These amphibians require cool temperatures of water (60-68oF), good filtration, and suitable substrate that will not result into impaction in case ingested. The aquarium also should have comfortable space, good concealments, and gentle water current which is not very strenuous to the animals.

Legal requirements also vary greatly depending on the jurisdiction, as to whether possession of the axolotl is allowed at all, or whether there are restrictions based on their potential to become an invasive species. Before purchasing axolotls prospective owners are to investigate local law and acquire the required permits.

The issue of the pet trade as an effect on wild populations of axolotls is again another factor, but captive breeding, appropriately regulated, can beated to increase diversity and save the existence of axolotls by taking them out of commerce.

Plans of the Future of Axolotl Conservation

The future of the axolotls lies in the hands of the ongoing, concerted measures that include habitat restoration, community participation and scientific research as well as international assistance. The present-day conservation initiatives prove the fact that recovery of the axolotls is feasible when the sufficient resources and political interest come along.

It is possible to scale up many of the successful projects such as the Chinampa Refugio Project and renew much of the ecosystem of Xochimilco, in addition to supporting the agricultural interests of the local people. Expansion plans include an increase in biofilter installations and establishment of refuge across 60 percent of the chinampas that still survive over the next 10-15 years.

The climate adaptation strategies will gain more relevance as we face global warming which has continued to affect the habitat of axolotl. To properly manage the fate of axolotl, it is important that the activities of conservation planning be reflected upon in terms of temperature management, water level maintenance, and connectivity of the habitat or location to allow the survival of the species despite the changing environmental conditions.

Effective international cooperation can be a key to environmental management since it aids research, provides financial assistance, and is a source of expertise in axolotl conservation. Meanwhile, the investment of the scientific community globally into working with the axolotl makes the further propagation of the species in the wild even more motivated by the progress that the scientific knowledge could achieve by implementing its potential.

The education and outreach programmes can contribute to the creation of the general support towards axolotls preservation on one hand but also to the environmental issues awareness on the other hand. Upon gaining knowledge about the existence of axolotl and their endangered status, people tend to be highly motivated and take actions to help preserve them and live more environmentally friendly.

The saga of the axolotl is at once frail and strong as life on earth. They are also amazing animals that have managed to stay alive over millions of years and have evolved to meet the physical needs of diverse ecological environments and they have acquired spectacular biological abilities. But they now face extinction through human activities that have changed their world in only decades.

But the same human resourcefulness which has made the problems, also provides solutions. Our understanding and abilities to save axolotls and other species works so well because of our innovative conservation strategies, commitment to scientific research and the increase in awareness about the subject. The question, now, arises as to whether we are going to be fast and decisive enough in our efforts to ensure the existence of these living treasures to make them available to generations to come.

Inclusion of the axolotl has more to do than with one more endangered species in need of protection; he is a symbol of how we treat the natural world and how we carry out our mandate as stewards of biodiversity. These Peter Pan salamanders bring home the realization that there are things that we simply cannot recreate no matter how advanced we can build science to be. Now is the moment to do so when there are still axolotls in the canals of Xochimilco and there is hope that they can and will be saved.

By donating to, educating, or taking responsible ownership of an axolotl, any of us can help the axolotls survive and continue to evoke fascination and contribute to scientific research today and in the future. The permanent smile of an axolotl should not become a memory, but the symbol of the ability of nature to recover and our will to save the genius of life diversity on the planet.