Population Analysis and Forensic Identification of Totoaba macdonaldi, an Endangered Species Endemic to the Gulf of California

Totoaba macdonaldi, is a large sciaenid endemic to the Gulf of California. Totoaba historically supported a substantial commercial fishery in the Sea of Cortez, at times yielding over 2000 metric tonnes a year. By the mid-1970’s, the Mexican government placed an infinite moratorium on fishing of totoaba, which included population assessments. The species is currently listed as CITES Appendix I. Little is known about the current condition of totoaba populations in the Gulf of California except that a thriving black market exists for their swim bladders, long considered a delicacy in the Chinese food markets. Habitat deterioration, poaching on adult fish, and bycatch of juvenile fish continue to provide challenges for recovery of totoaba. In 2013, several seizures of totoaba swim bladders were made by US and Mexican law enforcement agents, totaling over 800 individual fish. Information obtained from the swim bladders suggests that totoaba populations are more genetically diverse than their population abundance would suggest.  Active aquaculture activities, combined with knowledge of the population genetic characteristics of the wild-caught swim bladders allowed development of effective methods for forensic identification and tracking of totoaba swim bladders in legal and illegal markets.