Life History and Conservation of Totoaba macdonaldi

Abstract

We conducted a literature review on the biology, ecology, fishery, and protection of totoaba (Totoaba macdonaldi), an endemic, threatened fish of the Gulf of Calfornia, Mexico. Reinterpretation and integration of published and unpublished information enabled us to confirm and estimate specific biological parameters of the totooba, make hypothetical constructs of its life history, and to propose ideas for its preservation. In specific, we found (1) that the mean age of first reproduction of male and female totoaba are 6 and 7 years, respectively; (2) that the intrinsic rate of natural mortality was estimated as 0.268 per year and (3) that in the mid 1980s an estimated 120,300 juveniles died each year in the shrimp fishery by‐catch and 6200 adults (26 kg average weight) died due to poaching. The parameters of an individual growth model for juveniles and adults were also estimated. Decreased spring water input from the Colorado River into the Gulf of California may have caused a contraction of the spawning season and a reduction of the carrying capacity of juvenile totoaba. An increase in annual survival during recent years indicates recovery of the stock that might be related to protection of adults. We argue that habitat restoration, which includes the elimination of growth and recruitment over‐fishing, is critical to increasing numbers of totoaba, and thereby lifting the fishing ban, and to the delisting of totoaba.

Endemic Fishes of the Cortez Biogeographic Province (Eastern Pacific Ocean)

“…The Gulf croaker, Micropogonias megalops, represents almost 27% of the total fish capture in the Upper Gulf of California (Aragón-Noriega et al 2009). The totoaba, Totoaba macdonaldi, supported one of the most important fisheries in the region; nevertheless, uncontrolled fisheries and the decrease of Colorado River flow and thus spawning, breeding, and reproduction of this species brought this fishery to collapse (Cisneros-Mata et al 1995). Currently, the totoaba is included in NOM-059-SEMARNAT-2010 regulation in the category of risk of extinct, and as Critically Endangered by the IUCN red list of threatened Species.…”

Science, society, and flagship species: social and political history as keys to conservation outcomes in the Gulf of California

“…Like many sciaenid fish, totoaba form large spawning aggregations at the water surface (Erisman et al 2010). Despite limited fishing capacity at that time, focused effort on spawning grounds increased catches from 296 tonnes in 1932 to 2286 tonnes in 1942 (Cisneros-Mata et al 1995a). New cotton and nylon nets and motorized boats in the 1940s and 1950s allowed fishers to haul entire spawning aggregations of totoaba (Bahre et al 2000), followed by the start of industrialized shrimp trawl operations which caught juvenile totoaba (machorros) incidentally.…”

“…As the fishing sector struggled, fisheries scientists remained concerned about the totoaba population (Cisneros-Mata et al 1995a) while conservation groups (mostly U.S.-based) dedicated efforts to vaquita protection (McGuire and Valdez-Gardea 1997). Despite high uncertainty regarding population status or bycatch rates, vaquita was perceived by conservation advocates and scientists as a victim of lax environmental policy in Mexican fisheries and management (Fleischer and Pérez-Cortés 1996), a negative for NAFTA discussions.…”

The Emergence of Access Controls in Small-Scale Fishing Commons: A Comparative Analysis of Individual Licenses and Common Property-Rights in Two Mexican Communities

“…Historic sources of information included publications from several authors who reported historical data from the study region (i.e., Smith 1954;Malkin 1962;Cruz-Acosta 1979;Chenaut 1985;Felger and Moser 1985;Cisneros-Mata et al 1995;Bahre et al 2000;Bowen 2000;Basurto 2006). Recent sources of information were obtained through research efforts carried out by the authors of this study between 1995 and 2010, some of which have been published elsewhere (i.e., Bourillón 2002;Basurto 2005Basurto , 2008Basurto and Coleman 2010;Moreno et al 2005a, b;Cinti et al 2010a, b).…”