Totoaba - Critically Endangered Species

The totuava or totoaba is a marine fish and the only member of the genus Totoaba. It is endemic to the Gulf of California. The totoaba is categorized as a critically endangered species due to intensive fishing.

Life Cycle

The fish grows to about 6.6 ft in length and can weigh as much as 220 lbs, making it the largest member of the drum family alongside the Chinese bahaba. The lifespan of the totoaba is between 15-18 years while individual members reach maturity at the age of 6 or 7 years. They mostly feed on crustaceans and finned fish. Totoabas spawn in the Colorado Delta where the fingerlings spend their larval and juvenile lives before migrating to the Gulf of California as adults.

Commercial and Sport Fishing

Between the 1920s and 1940s, the commercial fishing produced over 2,000 metric tons of totoaba annually but by early 1970s only 50 tons were produced. In 1975, Mexico banned commercial fishing in an attempt to restore the natural population. Recent studies show that the population has stabilized although at low levels. Before the ban on the totoaba was affected in 1975, spearfishing was a popular method of catching the fish due to their large size. The spearfishing world record for the species was set on November 20, 1962, by Hal Lewis for a 74.5 lb totoaba.

Conservation

Mexico and the United States banned the fishing of totoaba in 1975 and 1976 respectively after the population of the fish was decimated to near extinction. In 2015, the Mexican president announced a government program to rescue and conserve the totoaba as the fish was still being caught as a bycatch of legal fishery. Despite the ban on the sale, the totoaba swim bladders are traded openly in Chinese black markets. More recently, Chinese and Mexican authorities have tightened screening of imports that resulted in large confiscations. Totoaba fish farms in China and Mexico provide fish for the food market and hatchlings to restore the wild population.

Threats

Fingerlings thrived at the mouth of the Colorado River where the natural salinity of the water was about 20 ppt until the river was diverted. The main stem of the Colorado River has 15 dams and the Glen Canyon Dam and Hoover Dam withhold 96% of the river’s flow resulting in salinity of about 35 ppt.

Poaching

Poaching remains the greatest threat to the totoaba population. The fish’s swim bladder is a delicacy in China while its meat is used to make soup. The bladders fetch millions of dollars in the black market as the Chinese believe they are a treatment for skin, circulatory, and fertility problems. The fish are smuggled to Hong Kong where screening of imports is lax before they are transported to mainland China. The totoaba became popular in China after the Chinese bahaba population became depleted.