Amphibians are semi-terrestrial cold-blooded vertebrates without body scales. They have metamorphic life cycles, transforming from eggs to larvae and finally into their adult forms. Mexico has 366 documented amphibian species, with 3 formerly present species already having gone extinct. The remaining species offer a rich and unique diversity regarding their behaviors, features, adaptations, and feeding patterns. Due to illegal logging, shifting agricultural practices, persecution of species and predation, these Mexican amphibians have been put at risk in their population with some attaining the critically endangered status.
Mountain Stream Siredon (Ambystoma altamirani)
The mountain stream siredon is in the family of mole salamanders. It is mainly found in central Mexico in the Valley of Mexico, as well as Southern Distrito Federal and northwestern Morelos in isolated populations. It metamorphoses and develops adult features such as nostrils and lungs for breathing. Some adults remain in water throughout their life while some are partially terrestrial returning to ponds to breed. The siredon occupies ponds of high elevations about 2700 to 3200 meters within pine or pine-oak woodlands with terrestrial adults occupying pasture lands. The adults have well developed coastal groves and are well patterned, a flattened body with a broad head and a large mouth as well as a rounded tail that appears compressed. The species grows up to 115 millimeters in length. The species is critically endangered due to severe population decline due to extensive habitat destruction.
Western Toad (Anaxyrus boreas)
The western terrestrial toad is native to western North America. The toad has a dusky gray or greenish skin with a white or cream dorsal stripe. The toad occupies Rocky Mountains, groves, and riparian forests. The western toad is diurnally active in low altitudes sometimes hibernating in the winter in high altitudes. They lay eggs in water after which metamorphosis for hatched eggs occurs within three months. The toads stay hidden during the day on the forest floor, in the soil under rocks, logs stumps or rodent burrows. They feed mainly on bees, beetles, ants, arachnids, crayfish, sowbugs, and grasshoppers. The species is near threatened due to predation by fish, reptiles, amphibians, mammals, and birds and contamination of the environment by agricultural chemicals.
Conservation of Mexican Amphibians
Other amphibians in Mexico include the lesser siren, hourglass tree frog, arboreal salamander, highland frog, black-spotted newt, and the spotted chirping frog. Regarding conservation of these species, steps that have been taken include implementation of conservation laws and policies and the demarcation of designated protected areas.