Critically Endangered Species of the Week: the Mexican Axolotl!

          This week we are starting off a series of posts each featuring a new critically endangered species! I decided to do this to highlight a few of the many species currently classified as ‘critically endangered’ due to human action (see the IUCN Red List), with the view that knowledge is a step in the right direction to changing attitudes, and to make people more conscientious about our affect on other species.

          One of my favourite strange creatures (I would love to see a wild one!), the Mexican Axolotl (Ambystoma mexicanum), is our first critically endangered species of the week:

                                                   Look at how cute it is - it's so smiley!

   But that's not the only reason to conserve a species of course...

       Photo by Stephen Dalton/Animals Animals at National Geographic.

         



About: 

A Mexican Axolotl with typical colouration.
Photo by Richard Griffiths at EDGE.

         The Mexican Axolotl is a species of salamander

(Order Caudata) fairly common in the pet trade, but extremely rare in the wild. Individuals often live in the larval state for the majority of their lives, inhabiting fairly deep-water lakes (a condition known as neoteny) - features include the external gills from the back of the head and a tad-pole like tail. In rare cases, Axolotls may metamorphose into the mature form, exiting the water.

         Axolotls are typically black or mottled brown, but captive individuals may often be albino, as in the photo above. They can live up to 15 years, and have a diet of molluscs, worms, insect larvae, crustaceans and some fish.

         The Mexican Axolotl is classified as critically endangered as of 2010 because its Area of Occupancy (where it lives) is under 10 square kilometres!



Geographical range of the wild Mexican Axolotl.

Number left in existence:

         The current wild population is very small, although numbers have not been recently assessed - surveys around 2002/03 found fewer than 100 individuals, but populations based on other studies appear to be decreasing (IUCN; Zambrano, 2006).

Geographical Range in the wild: 

         Found only in canals and wetlands in the vicinity of Lake Xochimilco, at the southern edge of Mexico city, central Mexico. The species has disappeared from most of the lakes in its original range.    

Why they are endangered:

• Urbanisation of the area polluting the canal and lake system native to the species, and local consumption of the species, have both contributed to their decline.
• Drainage of the lake system is destroying and causing fragmentation of their habitat.
• Increased, unregulated tourism causes further pollution.
• Young animals are targeted for medicinal purposes.
• Alien species of large fish introduced by humans (e.g. tilapia and carp) have increased competition and predation.
• Poor water quality from past pollution and invasive species appear to have spread disease.

The international pet trade also used to affect wild populations, but it is likely that most pets are now bred in captivity (so I can feel better about wanting one?).

What can we do to help?

       Conservation action is ongoing, focusing on raising the profile of Lake Xochimilco through education and nature tourism, and habitat restoration.

       When threats are mitigated, plans hope to reintroduce individuals from captive breeding colonies (from biomedical research due to their ability to regrow limbs!, and the pet trade)

For more information on the Mexican Axolotl, and to investigate my sources, visit EDGE, the IUCN or the National Geographic.