Taxonomic notes: The taxonomic validity of this species is confirmed, on the basis of morphology, allozymes, and mtDNA (H.B. Shaffer pers. comm.).

This species is known only from central Mexico, on the southern edge of Mexico City, in canals and wetlands in the general vicinity of Xochimilco (including outside the Xochimilco city limits, around the Chalco wetland). The animals are not homogeneously distributed through their range, and congregate in particular places. Records from close to downtown Mexico City in the Chapultepec Lake have been confirmed to be A. mexicanum (Parra, pers. comm).

It was originally found in Lakes Xochimilco and Chalco (and presumably in the connecting lakes Texcoco and Zumpango), but it has disappeared from most of its range.

The surviving wild population is very small. Although populations are difficult to assess, recent surveys covering almost all of its known distribution range have usually captured fewer than 100 individuals (e.g., during 2002 and 2003, more than 1,800 net casts were made along Xochimilco canals covering 39,173m² and this resulted in a catch of only 42 specimens; and only 2 individuals were captured in 2013). In a study covering a span of six years (from 1998 to 2004), axolotl density had reduced from 0.006-org/ m2 to 0.001-org/ m2, although it is thought that this reduction could also be due to its own population dynamics (Zambrano 2006). A recent scientific survey revealed no axolotls, although wild-caught animals are still found in the local market, which indicates that fishermen still know where to find them. There has not been a density study of the Chalco population, but evidence suggests that the population there is small and, furthermore, Chalco is a highly unstable system that runs the risk of disappearing in the near future.
Repopulation has been attempted by introducing close to 10,000 individuals in 2012.

FORO:
Un análisis de tablas de vida de A. mexicanum sugiere que la sobrevivencia durante el primer año de vida es crucial en la tasa de crecimiento poblacional del ajolote. Es probable entonces que los efectos sobre la población se den directamente sobre los ajolotes en esta edad. (ac-cites-mx).

This species is native to the ancient system of water channels and lakes in Mexico City. It requires deep-water lakes (both natural and artificial canals) with abundant aquatic vegetation. Structures such as plants are needed to lay eggs. It is a paedomorphic species, living permanently in water, and does not undergo complete metamorphosis.

Wild harvest is small but not necessarily in relation to population size. There is a local illegal trade in wild-caught animals for human consumption, medicinal uses and pets. It is assumed that all international trade is now in captive-bred animals.

The desiccation and pollution of the canal system and lakes in Xochimilco and Chalco, as a result of urbanization, as well as the traditional consumption of the species by local people, is threatening the survival of this species. Increased tourist activity is poorly regulated and adds further pollution (Zambrano, 2006).   It was formerly also captured for the international pet trade, although probably all animals in the international trade are now of captive origin. Introduced fishes (tilapia and carp) have increased to high abundances (a recent study collected 600kg of tilapia in one small channel using a 100m net) and have also impacted axolotls through competition and predation. The animals are also being affected by disease, probably spread by invasive species, and as a result of poor water quality. Although the water regime has changed in the last 10 years, and it is reported that pollution levels are decreasing, factors such as very high levels of bacterial contamination could still pose a serious threat.

FORO:

Dentro de las amenazas de los ajolotes de un año de vida, está la baja calidad de agua que puede producir crecimiento de hongos en los huevos o disminución en la viabilidad de eclosión.

La combinación de estas tres amenazas puede explicar por un lado, la distribución muy poco homogénea de los organismos y por otro lado la fuerte disminución de la población en los últimos años. Donde se han encontrado los ajolotes eran sitios con pocos contaminantes y poca abundancia de especies introducidas. Es muy probable estas condiciones en los canales de Xochimilco varíen año con año (los contaminantes y la distribución de carpas y tilapias, puede estar variando de canal en canal). Lo anterior sugiere que las poblaciones de ajolotes dependen de eventos fortuitos que generan zonas en 
donde no existan condiciones adversas para sus puestas. Estas regiones han ido disminuyendo conforme las aguas están aumentando su contaminación y las carpas y tilapias han ido poblando todos los canales del lugar. Por lo tanto, los ajolotes se están concentrando en los pocos sitios libres. Así los ajoloteros pescan en zonas específicas de sobrevivencia. Puesto que sus redes pueden colectar individuos menores a un año, afectan fuertemente también la tasa de crecimiento anual del organismo. (ac-cites.mx)

• 5.1.1 Intentional use (species is the target)
• 1.1 Housing & urban areas
• 9.2.3 Type Unknown/Unrecorded
• 1.3 Tourism & recreation areas
• 9.1.3 Type Unknown/Unrecorded
• 11.2 Droughts
• 9.4 Garbage & solid waste
• 8.1.1 Unspecified species
• 9.1.1 Sewage
• 9.3.4 Type Unknown/Unrecorded

Conservation action is focusing on raising the profile of Lake Xochimilco through conservation education and a nature tourism initiative, coupled with work on habitat restoration and bioremediation. A species action plan has been drafted. There are several captive colonies around the world, since the species is used in physiological and biomedical research, as well as in the pet trade. This species is protected under the category Pr (Special protection) by the Government of Mexico and is in process of being amended to a higher risk category. Although this species is currently on CITES Appendix II, it is currently under the process of "Periodic Review of species included in CITES Appendices".

FORO:
Es fundamental generar un programa de erradicación de las especies exóticas, en particular 
aquellas que cuentan con altas densidades dentro de Xochimilco (la carpa y la tilapia). La 
erradicación de especies exóticas del medio acuático requiere de una planeación precisa en 
cuanto a épocas y áreas de captura, así como seleccionar las artes de pesca apropiadas a fin 
de no afectar a las especies nativas de peces anfibios y crustáceos. Por lo tanto, son 
necesarios estudios de dinámica poblacionales por región y por especie a fin de proponer un 
programa viable con resultados exitosos. Es importante aclarar que la prohibición de la 
pesca en general solo favorece la proliferación de las especies exóticas y consecuentemente 
puede mantener el efecto negativos sobre las poblaciones de ajolote. Sin embargo, la pesca 
debe de ser enfocada únicamente a las especies introducidas. Es fundamental mantener la 
prohibición de la pesca del ajolote en estado natural. Es importante realizar un monitoreo 
de las zonas donde el ajolote ha sido encontrado a fin de implementar acciones de conservación (ac-cites-mx)
Based upon species´ distribution model, suitable habitat for this species has 13,8% of remnant distributional range of natural vegetation cover in Mexico (equivalent to 38,303 ha), but is just represented in 36% in protected areas (31% governmental PA; 5% social private efforts). Ochoa-Ochoa, L. Urbina-Cardona, J.N., Flores-Villela, O., Vázquez, L-B and Bezaury-Creel, J. 2009. The Effects of Governmental Protected Areas and Social Initiatives for Land Protection on the Conservation of Mexican Amphibians. PLoS ONE: 4 (9): e6878 (Nicolás Urbina)

• 3.1.2 Trade management
• 1.2 Resource & habitat protection
• 4.3 Awareness & communications
• 3.1.1 Harvest management
• 1.1 Site/area protection
• 2.2 Invasive/problematic species control
• 2.3 Habitat & natural process restoration

Listed as Critically Endangered because its Area of Occupancy is less than 10km2, its distribution is severely fragmented, and there is a continuing decline in the extent and quality of its habitat and in the number of mature individuals. Recent surveys have shown an extreme reduction in population size.

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