STEVENS, J. D, 



1974. The occurrence and significance of tooth cuts on the 

 blue shark tPrionace glauca L.) from British waters. J. 

 Mar. Biol. Assoc. U.K. 54:373-378. 



A. PETER KLIMLEY 



Graduate Department, A-008 

 Scripps Institution of Oceanography 

 La Jolla, CA 92093 



Department of Biology 

 California State University 

 Long Beach, C A 90840 



DONALD R. NELSON 



CLEANING SYMBIOSIS BETWEEN TOPSMELT, 

 ATHERINOPS AFFINIS, AND GRAY WHALE, 



ESCHRICHTIUS ROBUSTUS, IN LAGUNA SAN 

 IGNACIO, BAJA CALIFORNIA SUR, MEXICO 



sured and its gut contents examined. A second 

 series of topsmelt were collected during the same 

 winter in the absence of gray whales. 



The topsmelt ranged from 17 to 29 cm SL. All 38 

 specimens collected in association with gray 

 whales contained bits of sloughed gray whale 

 epidermis and whale lice appendages. No barnacle 

 appendages or other material was found in these 

 fish. None of 25 topsmelt collected in the absence of 

 whales contained any gray whale epidermis or 

 whale lice; rather they contained bits of filamen- 

 tous brown algae, Ectocarpus sp., and gammarid 

 amphipods. 



Topsmelt are described as opportunistic feeders 

 on marine plants, small crustaceans, bryozoans, 

 and hydroids (Frey 1971). During the breeding 

 season of the gray whale, topsmelt in Laguna San 

 Ignacio supplement their diets by cleaning slough- 

 ing epidermal tissue and external parasites from 

 gray whale hosts. 



Many species of marine fishes are known to en- 

 gage in various forms of cleaning symbiosis (Lim- 

 baugh 1961; Hobson 1969, 1971). The cleaners, 

 generally small or juvenile fish, remove ectopara- 

 sites and necrotic tissue from larger host fish. This 

 promotes the well-being of the host and provides 

 food for the cleaner. Cleaning symbiosis between 

 topsmelt, Atherinops affinis, cleaners and gray 

 whale, Eschrichtius robustus, hosts was observed 

 during the author's study of breeding gray whales 

 in Laguna San Ignacio, Baja California Sur, 

 Mexico, supported by the United States Marine 

 Mammal Commission, the National Geographic 

 Society, and the World Wildlife Fund-U.S. (Swartz 

 and JonesM. Topsmelt are perennial residents of 

 the lagoon and gray whales occupy the lagoon for 3 

 to 4 mo each winter. As we photographed gray 

 whales from our skiff, schools of topsmelt were 

 seen accompanying the whales and picking at 

 clusters of parasitic barnacles, Cryptolepas 

 rhachianecti, and whale lice, Cyamus sp., which 

 incrust these cetaceans (Rice and Wolman 1971). 

 Topsmelt in association with gray whales were 

 collected during the 1978-79 winter with a "mack- 

 erel rig" consisting of 1 m of monofilament line 

 with four No. 6 brass hooks spaced 10 cm apart. 

 The standard length (SL) of each fish was mea- 



'Swartz, S. L.. and M. L. Jones. 1978. Gray whales, Es- 

 chrichtius robustus, during the 1977-1978 and 1978-1979 winter 

 seasons in Laguna San Ignacio, Baja California Sur, 

 Mexico. Available Natl. Tech. Inf. Serv., Springfield, Va., as 

 PB-289 737, 35 p. 



Literature Cited 



FREY.H. W. (editor). 



1971. California's living marine resources and their utili- 

 zation. Calif Dep. Fish Game, 148 p. 

 HOBSON. E. S. 



1969. Comments on certain recent generalizations regard- 

 ing cleaning symbiosis in fishes. Pac. Sci. 23:35-39. 

 1971. Cleaning symbiosis among California inshore 

 fishes. Fish. Bull., U.S. 69:491-523. 

 LIMBAUGH.C. 



1961. Cleaning symbiosis. Sci. Am. 205(2):42-49. 

 RICE, D. W., AND A. A. WOLMAN. 



1971. The life history and ecology of the gray whale ^ Es- 

 chrichtius robustus). Am. Soc. Mammal. Spec. Publ. 3, 

 142 p. 



STEVEN L. SWARTZ 



Cetacean Research Associates 

 1592 Sunset Cliffs Boulevard 

 San Diego. CA 92107 



MORPHOLOGICAL FEATURES OF 



THE OTOLITHS OF THE SAILFISH, 



ISTIOPHORUS PLATYPTERUS, USEFUL 



IN AGE determination' 



Because of its spectacular runs and leaps, sailfish, 

 Istiophorus platypterus , is highly valued by sport 

 fishermen, and the fishery contributes substan- 

 tially to the economics of coastal regions (de Sylva 

 1969). However, information on the biology of sail- 



360 



FISHERY BULLETIN: VOL. 79, NO. 2, 1981. 



FISHERY BULLETIN: VOL. 79, NO. 2. I98L 



