IIOBSON: CLEANING SYMBIOSIS 



interspecific relations, by affecting not only the 

 relative availability of various prey organisms 

 and the incidence of various ectoparasites, but 

 also the species composition of the interacting 

 fishes themselves. 



In California the white seaperch likely is one 

 of those species that cleans only occasionally as 

 an incidental adjunct to regular foraging. Sever- 

 al other California species reported by Limbaugh 

 (1955) and Gotshall (1967) clean, including 

 black perch, pile perch, and rainbow seaperch, 

 but they have not been seen doing so by me. 

 The report of cleaning by the blacksmith (Tur- 

 ner et al. 1969) remains an anamoly. as this fish 

 does not fit the pattern of a bottom-picking pred- 

 ator described above. However, it may be sig- 

 nificant that many of those substrate-picking 

 predators which clean most frequently are spe- 

 cies that also feed on material adrift in mid- 

 water, as do the senorita, sharpnose seaperch, 

 and kelp perch. Thus this mode of feeding too, 

 including the taking of plankton, may, in some 

 species, favor adaptations that are suited to 

 cleaning. Fishes that are adapted to both sub- 

 strate-picking and plankton-picking may possess 

 adaptations especially well suited to cleaning. 



Probably many species of fishes clean inci- 

 dentally on isolated occasions, but relatively few 

 are habitual cleaners. And even the habitual 

 cleaners vary greatly in the degree to which they 

 are specialized for this habit. Species of the 

 Indo-Pacific labrid genus Labroides are highly 

 specialized cleaners that feed almost exclusively 

 on ectoparasitic crustaceans (Randall, 1958; 

 Youngbluth, 1968). These fishes possess many 

 specific morphological and behavioral specializa- 

 tions that are adapted to this way of life (Feder, 

 1966; Losey, 1971). However, only a small mi- 

 nority of cleaners are so highly specialized; most 

 are but part-time practitioners of the cleaning 

 habit, with much of their food being derived 

 from other sources. 



That some cleaners depend on ectoparasites 

 for prey, whereas others can subsist equally well 

 on food from other sources, has led to classifying 

 various species as either obligate or facultative 

 cleanei-s (e.g., Youngbluth, 1968) . The senorita, 

 sharpnose seaperch, and kelp perch may well 

 resist being so classified because their cleaning 



seems to be characteristic not so much of a spe- 

 cies as of just certain individuals. At least at 

 a given time, most senoritas do not clean, where- 

 as some seem to be facultative cleaners, and a 

 few might even be obligate cleaners. Juvenile 

 sharpnose seaperch follow a similar pattern, but 

 with a relatively higher incidence of individuals 

 that clean. Limited data can only suggest that 

 the status of the kelp perch may be similar. 



CLEANING INITIATED BY THE SENORITA 



Usually there seem to be fishes present that 

 need cleaning, as shown when a seiiorita identi- 

 fies itself as a cleaner by initiating action with, 

 say, a blacksmith or a topsmelt, and immediately 

 is converged upon by many other fish that crowd 

 in its way seeking attention. That such fishes 

 generally wait for a senorita to begin the clean- 

 ing, rather than attempting to initiate activity 

 themselves with one of the many senoritas 

 present, likely reflects a low probability of suc- 

 cess if they make the first move. If, as it seems, 

 the vast majority of sefioritas are not cleaners, 

 or at least not currently predisposed to clean, 

 then random efforts to solicit service would not 

 seem adaptive. 



This situation contrasts with that of the Ha- 

 waiian wrasse Labroides phthirophagus, of 

 which all individuals seem to be obligate cleaners 

 (Youngbluth, 1968), and which is not nearly 

 as abundant on Hawaiian reefs as the senorita 

 is in California. In centering their activity 

 around well-defined stations, the distinctive L. 

 phthirojihagus can be recognized readily by 

 others that need cleaning. Thus, not surpris- 

 ingly, cleaning encounters that involve L. phihi- 

 rophagns are regularly initi;>.ted by fishes seek- 

 ing cleaning (Losey, 1971). 



We have seen that under certain circumstances 

 various fishes initiate cleaning encounters 

 with sefioritas. Some fishes successfully do so 

 by hovering amid unusually dense concentra- 

 tions of senoritas, luit the overtures of such fish 

 are not directed at individuals ; rather, they are 

 broadcast to the assemblage at large. The suc- 

 cess of this tactic presumably follows the proba- 

 bility that an individual predisposed to clean oc- 

 curs among such a large number of sefioritas. 



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