Pietro Cassino from Nice Newts & Co
Ambystoma dumerilii is unique in many ways. Like its cousin, the axolotl, this salamander lives in a neotonic state. They therefore do not metamorphose and, consequently, only live in the aquatic state.
Lake Patzcuaro Salamander has been overexploited for human consumption and for medical purposes. The Dumerlii breeds only in this lake, in northwest Michoacan, Mexico, at an elevation of 1920 meters above sea level. Due to pollution of the water and some species of fish invasive, the future of this species is very uncertain. (The Dumerilii was introduced to Turtle Island to preserve the species).
These specimens can reach a length of 35 cm. Compared to terrestrial salamanders, Ambystoma Dumerilii is perfectly adapted to aquatic life, with very filamentous outer gills, its simplified shape, a caudal fin along the tail. Its massive head is flattened, which allows this salamander to be an extremely effective fish hunter (in its microcosm of course). Its basic color is gray-brown, but it can also have a reddish coloration with very purple gills. Depending on the temperature, the oxygen content and the chemistry of the water, the gills can vary in size and also branch out more. The pads and toes are chocolate brown. For animals bred in captivity, after many generations their dark brown toes are gone. The top of their head and body are covered with glands that secrete a milky substance with an unpleasant odor and bitter taste. This liquid is believed to work as a defense mechanism against predators.
REPRODUCTION The eggs are laid during the winter months when the lake water temperature cools to 9 ° C up to 1,500 eggs are laid in aquatic plants or stuck to stones. The eggs are left to chance, by the parents.
DIET With its large flattened head and quick reflexes, flattened head, the Dumerilii is a formidable hunter. In the wild, its main food source appears to be the dwarf crayfish (Cambarellus patzcuarensis), which in trade is orange in color. The larvae of insects and worms are also avidly eaten. In captivity, the dumerilii is shown to be a voracious. He will behave as if he is starving by standing and begging relentlessly in front of the glass and swimming up and down.
STATUS AND PROTECTION Due to its very limited presence in a single Mexican mountain lake, which has not been designated as a protected area, the Dumerilii is considered one of the most endangered species of salamanders. This species has been exploited for decades by fishermen for food and to make medicines for respiratory diseases. It is reported that 19 tonnes were fished in 1987, 12.5 tonnes in 1988, 1.7 tonnes in 1989, and 2 tonnes in 1991. Since 1991, fishermen have not been able to locate them, so their number is no longer measurable. The fishermen interviewed have not caught a single salamander in recent years! Due to the lack of sewage treatment facilities in Lake Pátzcuaro, with a city of over 50,000 inhabitants, this lake is heavily polluted by sewage. Increasing eutrophication causes an annual bloom of algae. In addition, predators, such as the highly invasive Tilapia species, have been introduced into the lake and are multiplying (eating the eggs and juveniles of the Dumerilii). The habitat of the salamander in Lake Patzcuaro is less than 10 km². The International Union for the Conservation of Nature (IUCN) lists Ambystoma dumerilii as "critically endangered". This species is also listed in the Convention on International Trade in Species of Wild Fauna and Flora (CITES), Appendix II Endangered, as one of the top 5 most endangered salamanders in the world!
Thanks to Pietro Cassino from Nice Newts & Co for these beautiful pictures of his Dumerilii