http://www.arkive.org/axolotl/ambystoma-mexicanum/image-G14938.html
Species Description
The Axolotl (Ambystoma mexicanum) is a critically endangered amphibian. It is also known as the “Mexican Walking Fish” or Mexican Salamander. Axolotls are normally brown, grey, or black with dark spots when found in the wild. White “leucistic” axolotls have been bred in captivity. Axolotls have external, branch-like, feathery gills. These increase the surface area available for oxygen exchange. Axolotls also retain a tadpole-like dorsal fin.
| http://www.caudata.org/forum/f46-beginner-newt-salamander-axolotl-help-topics/f48-axolotls-ambystoma-mexicanum/f62-axolotl-gallery/78237-my-axolotls-setups.html | The axolotl is a neotene, which means that it retains traits normally associated with the larval stage as a sexually mature adult. They reach maturity without undergoing metamorphosis. This is why axolotls retain their gills and live permanently underwater. In some cases, axolotls may metamorphose to the "adult" form, losing their gills and tailfin and gaining bigger lungs. However, this is extremely rare and is due to disrupted hormone balance. |
| Axolotls are cold-blooded, are usually about 9 inches long, and can live from five to fifteen years. They usually breed from March to June. They lay 100 to 300 eggs on plants and other available substrates. The eggs hatch after 10 to 14 days, and the young are immediately independent. They are able to reproduce at about 1.5 years old. The most interesting fact about axolotls is that they are capable of regenerating entire limbs. When they are wounded, tissue at the wound site exhibits stem cell-like behavior. No scar tissue is developed. This capability makes them very interesting to scientists. Population and Habitat | Metamorphosed Axolotl: |
In 2014, researchers thought that axolotls had become extinct in the wild. Since then, some wild axolotls have been identified; however, they are hard to find and an accurate population is unavailable. It is estimated that there are less than 100 individuals left in the wild.
| http://animals.nationalgeographic.com/animals/amphibians/axolotl/ | Axolotls live in the freshwater canals and wetlands around Lake Xochimilco in the Valley of Mexico on the southern edge of Mexico City. Originally, axolotls lived in both Lake Xochimilco and Lake Chalco. However, the lakes were drained and only parts of Lake Xochimilco remain. They live in water with a lot of aquatic vegetation. The total area that the axolotl lives in is less than 4 square miles. The population is severely fragmented throughout the range. |
Role in EcosystemGenerally, axolotls are the top natural predator in their environment. They are carnivores, and eat mollusks, arthropods, worms, crustaceans, insect larvae, and fish. In this way, they help control the populations of these organisms. Axolotls also can be food for predatory birds, such as herons, and nonnative fish. Cause of DeclineAxolotls are almost extinct, primarily due to the introduction of predatory fish and habitat loss. Invasive fish like tilapia and carp feed on the axolotl and their eggs. Aside from predation, these nonnative fish threaten the axolotl through competition for prey. Disease is also thought to be spread by invasive species, causing some of the decline of the axolotl. | Leucistic Axolotl: |
| http://en.academic.ru/dic.nsf/enwiki/2931203 | Another huge threat to axolotls is habitat loss due to urbanization. Land drainage, flood control, and sewage disposal have caused serious damage to the Mexico City water system. Severe drying in the valley where Lake Xochimilco is located has occurred, due to the digging of wells for the Mexico City population. Lake Chalco, one of the axolotls’ native habitats, was drained for drinking water. Only canals and swamps remain of Lake Xochimilco. Pollution is a major threat to the species. Agrochemical run off from farming has polluted the water of Xochimilco, along with trash and sewage. Bacterial contamination in poor water quality can cause disease and deformity in axolotls. |
Axolotls are still sometimes caught illegally for human consumption and medical use, and are found in the local fish market. Axolotls were commonly eaten by locals when their population was much larger. They are believed to cure respiratory illnesses. Axolotl extract can still be found in some cough medicines. Axolotls caught for these purposes are usually less than a year old, which means they have not had the chance to breed yet.
Initially many axolotls were captured for the international pet and research trades, but the axolotl breeds well in captivity. Many of the animals sold in the pet and research trades today are now born in captivity and are not taken from the wild.
Why Should We Care?
| Scientists use axolotls to study gene expression, embryology, regeneration, and neurobiology. They have amazing regenerative capabilities, and can even rebuild portions of their spines and brains without scarring. Even if axolotls go extinct in the wild, they will remain in captivity because of their value to research. Because wild populations are so small, however, not much is known about axolotls in the wild. Scientists still have a lot to learn. |  http://www.sciencemag.org/news/2014/05/slideshow-search-bizarre-amphibian |
| Aztec God Xolotl: | Axolotls are an important cultural icon in Mexico City. The name “axolotl” is Aztec, and some of its translations include “water dog” and “water monster”. Aztec lore says that the god Xolotl transformed himself into an axolotl to escape banishment. If the axolotl goes extinct, Mexico will lose one of its last remaining natural ties to the Aztecs. The approaching extinction of the axolotl is an indication of environmental collapse. Many other species in Xochimilco in addition to the axolotl are affected negatively by pollution. If Xochimilco cannot support wildlife, then soon it will be unusable for humans as well. |
Conservation Efforts
Most research dealing with axolotl conservation is based out of the National Autonomous University of Mexico (UNAM). UNAM is working with local farmers and fishermen, in addition to the zoos around Mexico City, to promote conservation of habitat.
| UNAM is promoting the use of traditional Aztec agricultural methods in Xochimilco, called chinampas. Chinampas are dry islands in the canals that are formed by piling up material from the lake bed. These “floating gardens” are used to plant crops, and they provide an alternative to using pesticides and fertilizers that pollute the water system. Farmers are encouraged to use material from the lake bed as fertilizer and to plant polycultures. Researchers are currently working with local farmers to develop an organic fertilizer from ground-up invasive tilapia. | Chinampas: |
| http://www.economia.unam.mx/eshet/ | UNAM is developing sanctuaries for the axolotl, and implementing a program to potentially reintroduce axolotls into the wild. Certain canals are blocked off with barriers, preventing invasive fish species from entering. Wild-type axolotls that have been bred in captivity are then released into the canals. Scientists will monitor them before deciding if they can be released into the rest of Xochimilco. They need to be sure that these organisms are able to survive and will not pose a threat to wild populations before the program can continue. Another project that UNAM is working on is to potentially find a new home for axolotls. The researched spot is an artificial lake in Tecámac, which is about an hour from the axolotls’ natural habitat. Scientists will eventually introduce axolotls into this lake. |
The Darwin Institute of Conservation and Ecology leads a Darwin Initiative for the survival of the axolotl and other species in Xochimilco. This initiative is designed to integrate tourism and conservation in Xochimilco. The hope is that, by promoting nature tourism, the initiative can help Mexico to develop a sustainable conservation plan for these species. Their plans have included producing sustainable souvenirs that are themed around axolotls, training field guides, and providing workshops to educate local schoolchildren. Partner organizations for the initiative include the National Commission for the Knowledge and Use of Biodiversity (CONABIO), Centro de Investigaciones Biologicas y Acuicolas de Cuemanco (CIBAC), and the Universidad Autonoma Metropolitana (UAM).
The Parque Ecológico Xochimilco (PEX) is a protected area that has been restored. It supports several endemic species, including the axolotl. PEX provides recreational family activities in order to educate locals around Xochimilco.
| http://www.doe.ky/marine/marine-parks-review/25-years-of-marine-parks/darwin-publications/ | Parque Ecológico Xochimilco: |
What You Can Do to Help
Because axolotls are found in such a small area, it can be hard to find ways to help them. I was unable to find any organizations that take donations for axolotl conservation.
| Here are some things you can do to help protect the axolotl:
| http://animals.nationalgeographic.com/animals/amphibians/axolotl/ |
Here are some things that you can do to prevent salamanders in your own ecosystem from nearing extinction:
- Do not touch or remove salamanders from their natural habitat. Because salamanders have very absorbent skin, any chemicals present on your hands could be absorbed and cause infections. Salamanders can also injure bones and muscles from struggling.
- Do not use chemical fertilizers, pesticides, or rat-poisons around your home. These chemicals can wash into nearby wetlands and kill salamanders.
- Do not fish in areas that contain many salamanders. They can be snagged on fishing lines and can swallow baited hooks.
- Do not remove or move around rocks by streams or branches and leaves from the forest floor. These often act as shelters for salamanders.
For additional tips on how you can protect salamanders in your own ecosystem, see http://www.savethesalamanders.com/how-you-can-help.html.
Below is a great documentary on axolotls!
https://www.youtube.com/watch?v=3e0IqAlK6QM
Sources
http://www.iucnredlist.org/details/1095/0
http://animaldiversity.org/accounts/Ambystoma_mexicanum/
http://eol.org/pages/1019571/overview
http://www.caudata.org/cc/species/Ambystoma/A_mexicanum.shtml
http://www.axolotl.org/
http://animals.nationalgeographic.com/animals/amphibians/axolotl/
http://www.independent.co.uk/environment/axolotl-found-in-mexico-city-lake-after-scientists-feared-it-only-survived-in-captivity-9148775.html
http://www.edgeofexistence.org/amphibians/species_info.php?id=552
http://www.nytimes.com/2012/10/31/world/americas/struggle-of-axolotls-mexicos-mythical-salamander.html?_r=0
http://www.darwininitiative.org.uk/documents/11018/4125/11-018%20AR2%20-%20edited.pdf
