IIOBSON: CLEANING SYMBIOSIS 



Material Removed from Other Fish by the 

 Sharpnose Seaperch 



To determine the food of cleaning' seaperch, 

 I examined the gut contents of 16 specimens, 

 74 to 122 mm long, that were speared as they 

 cleaned blacksmiths. Food items in their guts, 

 ranked as percentage of each item in the entire 

 sample, were as follows: caligid copepods, 68'^; ; 

 caprellid amphipods, IG^r; gnathiid isopod lar- 

 vae, 9%; algae, I'/r ; and unidentified items, 

 6'"r. Thus ectoparasitic caligids and gnathiids 

 made up 77^; of the material. All 16 specimens 

 contained ectoparasites; in fact, ectoparasites 

 constituted the vast bulk of the material in all 

 but one individual, which had fed more heavily 

 on caprellids. As with senoritas, when an apiire- 

 ciable amount of free-living material was pres- 

 ent, it was usually sharply divided from the ecto- 

 parasites and more digested to the rear in the 

 digestive tract. All the identifiable caligid cope- 

 13ods among this material were Califius hohsoni, 

 which is consistent with what is known of ecto- 

 parasites on blacksmiths, the sjiecies cleaned by 

 these seaperch, and indicates feeding habits si- 

 milar to those of the cleaning senorita, presented 

 above. 



Incidental Cleaning by a Close Relative 



Although sharpnose seaperch were not seen 

 in water less than 20 m deep, the white seaperch, 

 a very similar species, is frequently abundant 

 there. Tlie white seaperch was probably the 

 most numerous of the embiotocids during most 

 of the observations made at the 3- to 10-m lo- 

 cation off La Jolla. Underwater the white sea- 

 perch and the sharpnose seaperch are nearly 

 identical, but can be distinguished by the dusky 

 bordered caudal fin of the former and the black- 

 tipped pelvics and more pointed snout of the 

 latter. 



White seaperch are especially abundant in 

 groups of 10 or more close to surfgrass in 3 or 

 4 m of water off La Jolla. Typically they hover 

 head-down; in this attitude they are not solic- 

 iting cleaning but rather are intently regarding 

 the surface of the vegetation, at which they pick 

 occasionally. Tiny organisms that live on the 

 surfgrass are prey of these fish: five white sea- 



perch, 80 or 81 mm long, speared in this habitat, 

 were filled with (showing percent of total vol- 

 ume) caprellid amphipods (80%), gammarid 

 amphipods (5'"f), isopods (2%), fragments of 

 algae with encrusting bryozoans (lO^r ) , and un- 

 identified crustacean parts (3'r ). Quast (1968) 

 found that specimens from a kelp bed had fed 

 mostly on small bottom-dwelling crustaceans, 

 polychaetes and bivalves, as well as kelp frag- 

 ments, some of which were heavily encrusted 

 with bryozoans. Thus the bottom-picking feed- 

 ing habits of the white seaperch are very similar 

 to the noncleaning habits of the sharpnose sea- 

 perch. 



On one occasion, I saw a white seaperch swim 

 1 or 2 m above the surfgrass in company with 

 a lone blacksmith, which hovered head-down in 

 the manner tyincal of one that desired to be 

 cleaned. The white perch picked at the black- 

 smith's body several times, but the bout was 

 brief, and the perch soon joined a group of 8 

 to 10 others of its own kind near the surfgrass 

 below. This seaperch, which proved to be 79 mm 

 long, was speared, and its gut contents included 

 58 caprellid amphipods, a single gammarid am- 

 phipod, one small isopod, plant fragments with 

 encrusted bryozoans, and some unidentified non- 

 parasitic crustacean remains. No ectoparasites 

 were found; its food was similar to that of the 

 other white seaperch reported above. On an- 

 other occasion I saw a white seaperch cleaning 

 several blacksmiths over a sandy bottom in 12 m 

 of water, but this individual was not collected. 

 Probably the observed cleaning was no more 

 than a brief incidental activity for these fish. 

 At no other time did I see any indication of clean- 

 ing by this species, but perhaps the activity is 

 more frequent under appropriate conditions. 



CLEANING ACTIVITY OF 

 THE KELP PERCH 



Because the kelp perch is not abundant in the 

 La Jolla study area, where larger kelps are 

 sparse, most observations of cleaning by this 

 fish were made incidentally during other projects 

 in areas heavily forested with kelp. However, 

 these other projects generally were centered on 

 the sea floor, whereas kelp perch concentrate 



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