When the area undergoes drought for a sufficiently long period, gypsum precipitates and concentrates in the mud on the lake bed.

In the last five thousand years, this deposit of gypsum has occurred at just one period which coincided with the start of the decline of the classical Mayan civilisation.

It is also inhabited by a diverse number of species of birds, mammals and reptiles which are protected under Mexican law, as well as being on the IUCN Red List.

[4] An unusual feature of the lake is that it contains an inland population of the red mangrove (Rhizophora mangle), as well as Morelet's crocodile (Crocodylus moreletii) and various species of wading birds, although these have not been formally surveyed.

[5][6] The primary reason for the decline of the endemic pupfish is introduced species, notably the Nile tilapia and the tetra Astyanax fasciatus.