HOBSON: CLEANING SYMBIOSIS 



taken, especially as Limbaugh (1955, 1961) re- 

 ported senoritas entering the mouth of the kelp 

 bass and cleaning beneath the gill covers of the 

 garibaldi. Furthermore, such behavior has been 

 widely reported for some other cleaners, such as 

 species of Labroides (Eibl-Eibesfeldt, 1955; 

 Randall, 1958; and others), and some echeneids 

 are known to habitually feed on copepods from 

 the branchial cavities of sharks (Cressey and 

 Lachner, 1970) . Nevertheless, any such activity 

 by seiioritas must be relatively rare. In discuss- 

 ing this situation I limit my remarks to the 

 senorita, because data are jiresently insufficient 

 to determine whether the same may apply to 

 the sharpnose seaperch and kelp perch. 



Senoritas would not be expected to take par- 

 asites from the oral or branchial cavities as often 

 as species of Labroides or echeneids if for no 

 other reason than they simply are too large rel- 

 ative to most of the fishes they clean. Whereas 

 species of Labroides or the echeneids are small 

 enough to enter the oral and branchial cavities 

 of most of the fishes they service, the seiiorita 

 is nearly as large, and sometimes even larger, 

 than most of its clients. Significantly, Limbaugh 

 observed seiioritas cleaning within the oral and 

 branchial cavities of kelp bass and garibaldis, 

 both of which are relatively large species. Most 

 of the senorita's cleaning is directed toward 

 smaller species, like the blacksmith and the 

 topsmelt. 



The specialized techniques that would be re- 

 quired to prey on the parasites of the oral and 

 branchial cavities would probably pose another 

 problem to the senorita. In its regular habit 

 of taking parasites from the external surfaces 

 of fishes, the cleaning senorita concentrates on 

 just a few forms that not only are numerous 

 on many of the most abundant fishes, but also 

 are not too dissimilar from free-living prey of 

 the species. Sometimes these external forms 

 also occur in the branchial cavity, and some 

 similar forms, e.g., bomolochids (Figure 7), ha- 

 bitually occur there and in the oral cavity. But 

 the majority of parasites characteristic of the 

 branchial and oral cavities are aberrant forms, 

 e.g., dichelesthiids, chondracanthids, and lerne- 

 opodids (Figure 7), and these are unlike anj-- 

 thing else encountered bv the seiiorita. No one 



type predominates; rather, they occur in a wide 

 variety of forms, none widespread among the dif- 

 ferent species of fishes, and none especially 

 abundant (except on an occasional individual 

 fish) . Thus a cleaner probably could not subsist 

 on one type alone but would have to master a 

 repertoire of specialized techniques in order to 

 exploit enough of these varied forms to make 

 it worthwhile. And before access is gained to 

 the site of infestation, a much more refined clean- 

 er-host interaction must have evolved than is 

 necessary when parasites are simply cleaned 

 from the external body surface. No such re- 

 lation would evolve unless the cleaner acquired 

 the precise manipulations necessary to pick at- 

 tached pai-asites ofl" the gills without damaging 

 the delicate gill membranes. Obviously the 

 cleaning relation would not be adaptive if such 

 damage occurred. In short, to feed habitually 

 on parasites from the oral and branchial cavities 

 would seem to require a higher degree of spe- 

 cialization than has been demonstrated by the 

 seiiorita. It seems unlikely that such special- 

 ization would develop as long as the more abun- 

 dant and readily available forms on the body 

 surfaces continue to satisfy the cleaning needs 

 of the species. Certainly judging from the way 

 blacksmiths, topsmelt, and other fishes vigor- 

 ously compete to have their external parasites 

 removed, it would seem that there is little imme- 

 diate chance of these parasites falling into short 

 supply. 



CLEANING SYMBIOSIS AND THE 

 DISTRIBUTION OF SHORE FISHES 



In his often-cited report on cleaning symbiosis, 

 Limbaugh (1961: 48) stated: 



In my opinion it is the presence of the senorita and 

 kelp perch that brings the deep-water coastal and 

 pelagic fishes in.shore to the e<ige of the kelp beds 

 on the California coast. Most concentrations of reef 

 fishes may similarly be understood to be cleaning 

 stations. Cleaning stations would therefore account 

 for the existence of such well-known California sport- 

 fishing grounds as the rocky points of Santa Catalina 

 Island, the area around the sunken ship Valiant off 

 the shore of Catalina, the La Jolla kelp beds and sub- 

 marine canyon and the Coronado Islands. 



Presumably this conclusion was intuitive, as no 



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