What are the main threats?
The justification for their inclusion on the IUCN Red List is numerous: first is their very small area of occupancy (i.e. their habitat range) which is less than 10 square kilometers (approx. 3.9 square miles). In fact the axolotl can only be found in just six isolated areas within one region of Mexico. This demonstrates the level of fragmentation of their habitat and is another key reason why there are listed as endangered. Human development (i.e. dams, farming land) cuts populations off from one another and prevents easy access to resources. Another key factor behind their endangered status is the deteriorating water quality of the canals they inhabit. Again this is caused by anthropogenic activities with the growing urbanization of Mexican cities leading to increased pollution levels resulting from surface water run-off.
A new threat in the form of invasive species is adding to the pressure currently impacting the axolotl population. In particular the introduction of carp and tilapia fish species is a particular concern to the future of the population. These have been released into the Peubla region due to their importance in controlling aquatic weeds and insects. However both species out compete axolotls for resources and the tilapia fish will also consume axolotl eggs. The latter in particular has shown huge increases in abundance in recent years with one survey finding 600 kilograms (approx. 1,322 pounds) of tilapia fish within a single 100 meter net. Furthermore axolotls are also targeted by local fishermen both for their use in traditional dishes as well as for medicinal purposes.