e Status of Shark and Ray Fishery Resources in the Gulf of California: Applied Research to Improve Management and Conservation Joseph J. Bizzarro, Wade D. Smith, Robert E. Hueter, John Tyminski, J. Fernando Márquez–Farías, J. Leonardo Castillo–Géniz, Gregor M. Cailliet, and Carlos J. Villavicencio–Garayzar Moss Landing Marine Laboratories Tech. Pub. 2009–01 ISSN 1088-2413 THE STATUS OF SHARK AND RAY FISHERY RESOURCES IN THE GULF OF CALIFORNIA: APPLIED RESEARCH TO IMPROVE MANAGEMENT AND CONSERVATION Joseph J. Bizzarro, Wade D. Smith, Robert E. Hueter, John Tyminski, J. Fernando Márquez– Farías, J. Leonardo Castillo–Géniz, Gregor M. Cailliet, and Carlos J. Villavicencio–Garayzar This research was made possible largely through funding provided by the DAVID AND LUCILE PACKARD FOUNDATION August 31, 2007 1 Copyright © 2009 by Joseph J. Bizzarro and Wade D. Smith Cover Photos: Landings of smoothound sharks (Mustelus spp.) and a Pacific Angel shark (Squatina californica); fishermen placing salted shark fillets on drying racks Author Affiliations: Joseph J. Bizzarro and Gregor M. Cailliet, Pacific Shark Research Center, Moss Landing Marine Laboratories, 8272 Moss Landing Rd., Moss Landing, CA 95039; [email protected]; Wade D. Smith, Oregon State University, Dept. of Fisheries and Wildlife, 104 Nash Hall, Corvallis, OR 97339–1086, United States; [email protected]; Robert E. Hueter and John Tyminski, Center for Shark Research, Mote Marine Laboratory, 1600 Ken Thompson Pkwy., Sarasota, FL 34236; J. Fernando Márquez–Farías; Facultad de Ciencias del Mar, Universidad Autonoma de Sinaloa, Paseo Claussen S/N. Col. Los Pinos CP 82000, Mazatlan, Sinaloa, Mexico; J. Leonardo Castillo–Géniz, Programa Tiburón, Centro Regional de Investigación Pesquera de Ensenada, B.C., Instituto Nacional de la Pesca, carr. Tijuana–Ensenada km 97.5, El Sauzal de Rodríguez, A.P. 1306, Ensenada, B.C., México; Carlos J. Villavicencio–Garayzar, Laboratorio de Elasmobranquios, Departmento de Biologia Marina, Universidad Autonoma de Baja California Sur, A.P. 19–B., La Paz, B.C.S., México CP 23080 Citation: Bizzarro, J.J., Smith, W.D., Hueter, R.E., Tyminski, J., Márquez–Farías, J.F., Castillo–Géniz, J.L., Cailliet, G.M., Villavicencio–Garayzar, C.J., 2007. The status of shark and ray fishery resources in the Gulf of California: applied research to improve management and conservation. Moss Landing Marine Laboratories Tech. Pub. 2009–01. An electronic version of this document can be found at: http://psrc.mlml.calstate.edu/current-research/gulf-of-california/ ISSN 1088–2413 2 TABLE OF CONTENTS Abstract..........................................................................................................................................4 Introduction....................................................................................................................................5 Study Site Description ...................................................................................................................9 Materials and Methods.................................................................................................................14 The Artisanal Elasmobranch Fishery of Baja California.............................................................19 Introduction......................................................................................................................20 Materials and Methods.....................................................................................................22 Results..............................................................................................................................22 Discussion........................................................................................................................32 The Artisanal Elasmobranch Fishery of Baja California Sur ......................................................39 Introduction......................................................................................................................40 Materials and Methods.....................................................................................................42 Results..............................................................................................................................42 Discussion........................................................................................................................50 The Artisanal Elasmobranch Fishery of Sonora ..........................................................................55 Introduction......................................................................................................................56 Materials and Methods.....................................................................................................58 Results..............................................................................................................................59 Discussion........................................................................................................................74 The Artisanal Elasmobranch Fishery of Sinaloa .........................................................................81 Introduction......................................................................................................................82 Materials and Methods.....................................................................................................83 Results..............................................................................................................................84 Discussion........................................................................................................................90 Overall Results and Conclusions .................................................................................................96 Recommendations......................................................................................................................116 Acknowledgements....................................................................................................................124 Literature Cited ..........................................................................................................................125 Tables.........................................................................................................................................149 Figure Captions..........................................................................................................................181 Figures........................................................................................................................................184 Appendices.................................................................................................................................212 3 ABSTRACT Seasonal surveys were conducted during 1998–1999 in Baja California, Baja California Sur, Sonora, and Sinaloa to determine the extent and activities of artisanal elasmobranch fisheries in the Gulf of California. One hundred and forty–seven fishing sites, or camps, were documented, the majority of which (n = 83) were located in Baja California Sur. Among camps with adequate fisheries information, the great majority (85.7%) targeted elasmobranchs during some part of the year. Most small, demersal sharks and rays were landed in mixed species fisheries that also targeted demersal teleosts, but large sharks were usually targeted in directed drift gillnet or, to a lesser extent, surface longline fisheries. Artisanal fishermen were highly opportunistic, and temporally switched targets depending on the local productivity of teleost, invertebrate, and elasmobranch fishery resources. Major fisheries for small sharks (< 1.5 m, “cazón”) were documented in Baja California during spring, in Sonora during autumn–spring, and in Sinaloa during winter and spring. Triakid sharks (Mustelus spp.) dominated cazón landings in the northern states, whereas juvenile scalloped hammerheads (Sphyrna lewini) primarily supported the fishery in Sinaloa. Large sharks (> 1.5 m, “tiburón”) were minor components of artisanal elasmobranch fisheries in Sonora and Sinaloa, but were commonly targeted during summer and early autumn in Baja California and Baja California Sur. The pelagic thresher shark (Alopias pelagicus) and silky shark (Carcharhinus falciformis) were most commonly landed in Baja California, whereas a diverse assemblage of pelagic and large coastal sharks was noted among Baja California Sur landings. Rays dominated summer landings in Baja California and Sinaloa, when elevated catch rates of the shovelnose guitarfish (Rhinobatos productus, 13.2 individuals/vessel/trip) and golden cownose ray (Rhinoptera steindachneri, 11.1 individuals/vessel/trip) primarily supported the respective fisheries. The Sonoran artisanal elasmobranch fishery was the most expansive recorded during this study, and rays (especially R. productus) dominated spring and summer landings in this state. Seasonal catch rates of small demersal sharks and rays were considerably greater in Sonora than in other surveyed states. Many tiburón populations (e.g., C. leucas, C. limbatus, C. obscurus, Galeocerdo cuvier) have likely been overfished, possibly shifting effort towards coastal populations of cazón and rays. Management recommendations, including conducting demographic analyses using available life history data, determining and protecting nursery areas, and enacting seasonal closures in areas of elasmobranch