Not the Fire-Inhabiting Mythical Creature:
The Sonora Tiger Salamander
By: Ricardo Gustavson
Species: The Sonora tiger salamanders begin their life as jelly-coated eggs laid from January to April, which hatch into aquatic larvae with gills. These larvae either grow into branchiates or terrestrial salamanders. Branchiate salamanders are gilled aquatic adults with a crest running down their backs, they grow up to 15 inches long, and are an olive-gray color.
Terrestrial salamanders rid themselves of their gills and crest through mutation and develop lungs, but they do not lose their ability to live in water. They can grow up to 13 inches long and are black with yellow spots and stripes, closely resembling the Arizona and barred tiger salamanders. Terrestrial salamanders can live in places like crevices and rotted logs during the dry season or stay in the pond. During the rainy season they leave the pond at night and return to breed at the pond. A majority of Sonora tiger salamanders are paedomorphic, meaning they reach sexual maturity and breed while in larval form. Mutated salamanders are the only form of the salamander that can migrate ponds to avoid drying or disease outbreaks that kill most branchiates and larvae.
Habitat: Sonora tiger salamanders only inhabit the grasslands and woodlands of the San Rafael Valley in Santa Cruz, the Cochise counties in southeastern Arizona, and the most northern parts of Sonora, Mexico. Above all else, these salamanders require a habitat with access to standing water year round for breeding, growth, and development. This much needed habitat quality can prove to be a good habitat for introduced non-native fish, bullfrogs, and crayfish that prey on the salamander eggs and larvae. Sonora tiger salamanders once called spring-fed marshes their home, but these habitats, along with natural standing water habitats, within the San Rafael Valley dried up and disappeared due to severe and rapid erosion in the late 19th and early 20th centuries. Most of the only good breeding grounds the Sonora tiger salamanders have left are artificial ponds created by farmers for watering livestock.
The Sonora Tiger Salamander is currently listed as endangered without critical habitat. The subspecies has been found in 53 ponds throughout San Rafael Valley. These salamanders are threatened by restricted distribution, loss of habitat, predation by non-native fish, bullfrogs, and crayfish, genetic swamping (reducing the Sonora tiger salamander's genetic diversity) by non-native barred tiger salamanders, disease, low genetic diversity, and collection for use as bait.
Recovery Plan: The recovery plan for the Sonora tiger salamander seeks to reclassify the subspecies' statues from threatened to endangered, and to eventually delist it. In order for this to happen, all recovery criteria must be met.
Recovery Criteria: The salamander will be reclassified as threatened when approximately 90% of its currently-occupied range and 90% of current breeding ponds are under protection and care to prevent habitat loss and degradation, predator introductions, barred tiger salamander introductions, and collection of salamanders for use as bait. The population must be monitored over a five year period through scientifically credible methods, and results must convey that the population is not in decline and that there are no new threats to the subspecies. Delisting the subspecies will be considered once criteria, based on research and continued monitoring, for number of breeding populations, amount, range occupied, and available habitat are defined and met. In order to ensure long-term protection of the subspecies, implementation of regulations and land management commitments that revolve around habitat maintenance and protection, controlling non-native predators, spread of disease, interbreeding with non-native salamanders, collection of salamanders, and public education are key.
Salamanders have been around since the times before dinosaurs walked this earth, if we can follow the recovery plan these little guys will surely stick around long after we're gone.
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