Whilst there are large numbers of axolotls in captivity around the world, particularly in biomedical and physiological research laboratories, numbers of wild axolotls are very low. Previously, capture of this species for the international pet and research trade contributed to population declines, but the axolotl now breeds well in captivity, alleviating this threat. It was also captured for consumption by local people, although numbers are now too low for this. The most significant threat to the axolotl is the increasing pollution of the lakes and canal system as Mexico City continues to grow (1). Land drainage, flood control and sewage disposal methods from the 17th century to the present have all contributed to the destruction of the water system of Mexico City (3).