458 
Fishery Bulletin 115(4) 
Kohatsu, A. Sanchez, and A. Arevalo for assistance in 
collecting, analyzing, and identifying samples, and B. 
Ramsby for assistance in designing the figures. 
Literature cited 
Abitia-Cardenas, L. A., F. Galvan-Magana, and J. Rodriguez- 
Romero. 
1997. Food and energy values of prey of striped marlin, 
Tetrapturus audax, off the coast of Mexico. Fish. Bull. 
95:360-368. 
Alfaro-Shigueto, J., J. C. Mangel, M. Pajuelo, P. H. Dutton, J. 
A. Seminoff, and B. J. Godley. 
2010. Where small can have a large impact: structure and 
characterization of small-scale fisheries in Peru. Fish 
Res. 106:8-17. 
Argiielles, J., R. Tafur, A. Taipe, P. Villegas, F. Keyl, N. 
Dominguez, and M. Salazar. 
2008. Size increment of jumbo flying squid Dosidicus gigas 
mature females in Peruvian waters, 1989-2004. Prog. 
Oceanogr. 79:308-312. 
Bolano Martinez, N. 
2009. Ecologia trofica del tiburon martillo Sphyrna zygae¬ 
na (Linnaeus, 1758) en aguas Ecuatorianas. M.S. the¬ 
sis, 140 p. Institute Politecnico Nacional, Centro Inter¬ 
disciplinary de Ciencias Marinas, La Paz, Mexico. 
Bon5.1, R. 
1994. Overview of world elasmobranch fisheries. FAO 
Fish. Tech. Pap. 341, 119 p. Rome, Italy. 
Braccini, J. M., B. M. Gillanders, and T. I. Walker 
2005. Sources of variation in the feeding ecology of the 
piked spurdog ( Squalus megalops ): implications for in¬ 
ferring predator-prey interactions from overall dietary 
composition. ICES J. Mar. Sci. 62:1076-1094. 
Casper, B. M., A. Domingo, N. Gaibor, M. R. Heupel, E. Kotas, 
A. F. Lamonaca, J. C. Perez-Jimenez, C. Simpfendorfer, W. 
D. Smith, J. D. Stevens, A. Soldo, and C. M. Vooren. 
2005. Sphyrna zygaena. The IUCN Red List of Threat¬ 
ened Species 2005: e.T39388A10193797. [Available from 
website, accessed June 2016.] 
Castaneda, J., and L. Sandoval. 
2004. Habitos alimentarios de los tiburones martillo 
Sphyrna lewini y Sphyrna zygaena en el Pacifieo Ecu- 
atoriano. Bachelor’s thesis, 138 p. Univ. Jorge Tadeo 
Lozano, Bogota, Colombia. 
Cheung, G. C. K., and C. Y. Chang. 
2011. Cultural identities of Chinese business: networks 
of the shark-fin business in Hong Kong. Asia Pac. Bus. 
Rev. 17:343-359. 
Chirichigno, N., and M. R. Cornejo. 
2001. Catalogo comentado de los peces marinos del Peru, 
314 p. Publ. Espec. Inst. Mar Peru, Callao, Peru. 
Christensen, V., and D. Pauly. 
1992. ECOPATH II—software for balancing steady-state 
ecosystem models and calculating network characteris¬ 
tics. Ecol. Model. 61:169-185. 
Clarke, M. R. (ed.). 
1986. Handbook for the identification of cephalopod 
beaks, 273 p. Clarendon Press, Oxford, UK. 
Clarke, K. R. 
1993. Non-parametric multivariate analysis of changes in 
community structure. Aust. J. Ecol. 18:117-143. 
Cortes, E. 
1997. A critical review of methods of studying fish feed¬ 
ing based on analysis of stomach contents: application to 
elasmobranch fishes. Can. J. Fish. Aquat. Sci. 54:726- 
738. 
1999. Standardized diet compositions and trophic levels of 
sharks. ICES J. Mar. Sci. 56:707-717. 
Cortes E., F. Arocha, L. Beerkircher, F. Carvalho, A. Domingo, 
M. Heupel, H. Holtzhausen, M. N. Santos, M. Ribera, and 
C. Simpfendorfer. 
2010. Ecological risk assessment of pelagic sharks caught 
in Atlantic pelagic longline fisheries. Aquat. Living Re¬ 
sour. 23:25-34. 
Croxall, J. P., and P. A. Prince. 
1932. Caloric content of squid (Mollusea: Cephalopoda). 
Br. Antarct. Surv. Bull. 55:27-31. 
Diemer, K. M., B. Q. Mann, and N. E. Hussey. 
2011. Distribution and movement of scalloped hammer¬ 
head Sphryna lewini and smooth hammerhead Sphyrna 
zygaena sharks along the east coast of southern Afri¬ 
ca. Afr. J. Mar. Sci. 33:229-238. 
Espinoza, P. 
2014. Trophic dynamics in the northern Humboldt Cur¬ 
rent system: insights from stable isotopes and stomach 
content analyses. Ph.D. diss., 131 p. Univ. Bretagne 
Occidentale, Brest, France. 
Estupinan-Montano, C., and L. Cedeno-Figueroa. 
2005. Estudio de los habitos alimenticios mediante el 
analisis del contenido estomacal del tollo mico Carcha- 
rhinus falciformis (Bibron, 1839) y los tiburones mar¬ 
tillo Sphyrna lewini (Griffith & Smith, 1834) y Sphyrna 
zygaena (Linnaeus, 17758) en el area de Manta—Ecua¬ 
dor. Bachelor’s thesis, 133 p. Univ. Laiea Eloy Alfaro, 
Manabf, Ecuador. 
Fischer, J., K. Erikstein, B. D’Offay, S. Guggisberg, and M. 
Barone. 
2012. Review of the implementation of the International 
Plan of Action for the conservation and management 
of sharks. FAO Fish. Aquat. Circ.1076, 120 p. FAO, 
Rome. 
Fowler, S. L., R. D. Cavanagh, M. Camhi, G. H. Burgess, G. 
M. Cailliet, S. V. Fordham, C. A. Simpfendorfer, and J. A. 
Musick (eds.). 
2005. Sharks, rays and chimaeras: the status of the chon- 
driehthyan fishes, 481 p. Status survey. IUCN/ SSC 
Shark Specialist Group. IUCN, Gland, Switzerland and 
Cambridge, UK. 
Francis, M. P. 
2016. Distribution, habitat and movement of juvenile 
smooth hammerhead sharks ( Sphyrna zygaena ) in north¬ 
ern New Zealand. N. Z. J. Mar. Freshw. Res. 50:506-525. 
Galvan-Magana, F., H. J. Nienhuis, and A. P. Klimley. 
1989. Seasonal abundance and feeding habits of sharks of 
the lower Gulf of California, Mexico. Calif. Fish Game 
75:74-84. 
Galvan-Magana, F., C. Polo-Silva, S. B. Heranandez-Agu- 
ilar, A. Sandoval-Londono, M. R. Ochoa-Diaz, N. Aguilar- 
Castro, D. Castaneda-Suarez, A. Cabrera Chavez-Costa, A. 
Baigorrf-Santacruz, Y. E. Torres-Rojas, et al. 
2013. Shark predation on cephalopods by sharks in the 
Mexican and Ecuadorian Pacific Ocean. Deep-Sea Res. 
II 95:52-62. 
Garcia-Godos Naveda, I. 
2001. Patrones Morfologicos del otolito sagitta de algu- 
nos peces oseos del mar Peruano. Bol. Inst. Mar Peru 
20(1—2): 1-61. 
