The Axolotl, also known as the Mexican monster, is a curious little salamander found in Mexico. However, Mexican biologists are starting to worry now that axolotls may have become extinct in their natural habitats. 

While axolotls are also sometimes referred to as "walking" fish, they are actually a species of amphibians. Aside from their distinct appearance, axolotls are also known for another interesting biological feature. When an axolotl's limb is severed, it can easily regenerate the entire appendage in a period of months. While this ability can also be found in other amphibians, this type of regenerative ability is more pronounced in axolotls, which are sometimes known to even regenerate damaged vital organs.

Last year, researchers were frantically searching the lakes in Mexico city for wild populations of axolotls. Their search, however, yielded little results. While there are still a number of axolotls alive in captivity, their wild counterparts have seemingly vanished. Tovar Garza, a biologist from Mexico's Autonomous University was part of the search and he hinted that the axolotl "is in serious risk of disappearing" from their natural habitat.

"Four months of sampling - zero axolotls," said Garza, when describing the efforts to document and catalog the existing axolotls in the wild.

While Garza has stated that declaring the axolotl's wild brethren as extinct may be premature, the creature's long-term prospects of survival in the wild seem grim. Back in 1998, the Mexican Academy of Sciences released their findings that indicate average axolotl distributions of 6,000 individuals per square kilometer. Another study conducted in 2003 showed a marked drop in axolotl densities at 1,000 individuals per square kilometer. The number dipped even further by 2008 with only 100 axolotls found per square kilometer.

The surveys "on almost all the canals have to be repeated, because now we are in the cold season, with lower temperatures, and that is when we ought to have more success with the axolotls, because it is when they breed," said Garza. 

Scientists have been taking great pains to preserve the natural habitats of these creatures to encourage population growth. Conservation measures include adding reeds and rocks to select axolotl habitats to improve their chances of survival. Moreover, the scientists are also trying to isolate the axolotls to protect them from non-indigenous fishes such as tilapia and carp.