30 DECEMBER 2016 • WORLD AQUACULTURE • WWW.WAS.ORG m, and live up to 30 years (Berdegue 1955). Their body is elongated with a sharp snout, large oblique mouth, and a projecting lower jaw. Juveniles eat mainly small crustaceans off the bottom and smaller fish from the water column. Totoaba are schooling fish endemic to the Sea of Cortez in Mexico (NOAA 2016). Adults are one of the top predator fishes in the upper Sea of Cortez and have pelagic feeding habits, favoring sardines and anchovies, although benthic crustaceans, such as shrimps and crabs are also part of their diet (Cisneros-Mata et al. 1995). Totoaba spawn during the late spring in the turbid waters of the Colorado River delta, a biosphere reserve at the northernmost tip of the Sea (Fig. 2). Juveniles typically stay in that area for one or two years before migrating south on the peninsular side, following the schools of sardines and anchovies on which they feed. Their summer feeding grounds extend south to Bahia Concepcion on the Baja Peninsula, and occasionally farther south to the Bay of La Paz (Valenzuela-Quiñonez 2014), and possibly even as far as San Jose del Cabo (Peet 2009). However, we recently received a trustworthy record and photographs of an approximately 45-kg totoaba captured south of Puerto Vallarta, much farther to the south of the reported range of the species. Fish in these summer feeding areas are thought to cross the Sea to the mainland side, south to the delta of the Fuerte River in Sinaloa, where they feed during the fall. Once they become adults after another 4 or 5 years, schools of totoaba migrate northward in the winter along the eastern coast of the Sea of Cortez, returning This is the story of the totoaba Totoaba macdonaldi, an iconic and highly valuable fish from the Sea of Cortez (also known as the Gulf of California) in Mexico. Overfished to commercial depletion in the first half of the twentieth century, the species is currently listed as critically endangered and it continues to be threatened by illegal fishing, habitat degradation, and insufficient enforcement of fishing and environmental regulations. Few fish are as interesting as the totoaba from the standpoints of biology, conservation, sociology, and regulation. Now aquaculture has the potential to bring totoaba back as a sustainable resource and to generate prosperity in an economicallydepressed region of Mexico. Totoaba are remarkably well-suited for aquaculture. Hatchery and growout technologies have been developed and commercial production trials are currently underway. Totoaba growth is among the fastest reported for any farmed marine fish and their quality as a food fish is high. Their status as a critically-endangered species presents unique challenges. In this article we present the history of the fishery and how perverse economic incentives and enforcement challenges resulted in its commercial depletion. We go on to present current advances in hatchery and grow-out and to show how regulatory considerations affect the species, leading to an opportunity for fishermen, regulators, researchers, aquaculturists, and conservationists to work together to restore the fishery, promote regional socio-economic development, and ensure the preservation of this iconic species for future generations. The totoaba (Fig. 1) is the largest of the Sciaenidae, a family that includes fish commonly known as drums, croakers, corvinas, and sea bass. Totoaba can reach a weight of 135 kg, a length of 2 Totoaba Aquaculture and Conservation: Hope for an Endangered Fish from Mexico’s Sea of Cortez Lorenzo M. Juarez, Pablo A. Konietzko and Michael H. Schwarz FIGURE 1. Adult totoaba in a broodstock maturation tank at the Earth Ocean Farms hatchery. EOF photo by Fernando Cavalin. FIGURE 2. Map of Northwest Mexico showing the Gulf of California and sites relevant to the totoaba fishery (mapmaker. nationalgeographic.org, with permission).
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