Comments: The apparent distributional hiatus between the Rio Grande and Pecos River populations in Texas possibly results from pollution from runoff from oil and natural gas wells (Ward 1984).
Riverine and riparian habitat along the lower Rio Grande has been degraded by dams, flood control practices, stream channelization, water diversion, and tamarisk invasion; water quality has declined, and streamflow has become increasingly intermittent (Blackstun et al. 1998, Bailey et al. 2008).
In New Mexico, apparent declines have been attributed to degradation of habitat through stream dewatering, loss of vegetation, and pollution (Schmitt et al. 1985, cited but not referenced by Biota Information System of New Mexico).
Some turtles are killed wantonly by anglers or gunners. Bailey et al. (2008) observed several that had been shot or otherwise killed at fishing camps in Texas. Reportedly wild-caught individuals have been offered for sale in the pet trade in recent years (Bailey et al. 2008). Disappearance from a locality in Texas may have been associated with commerical exploitation and exportation (Dixon 2000).
The role that disease may play in the population dynamics of this species is unknown.