HOBSON: CLEANING SYMBIOSIS 



come especially intolerant of the presence of 

 other fish species. Clarke (1970) recorded the 

 number of times garibaldis, in defence of their 

 territory, attacked fish of various other species 

 at different times of the year. He found that 

 when males were guarding eggs their attacks on 

 senoritas increased elevenfold. Not surpris- 

 ingly, I saw no cleaning of garibaldis that were 

 guarding eggs. At other times of the year male 

 garibaldis do not guard their territory as vigor- 

 ously against members of other species and are 

 frequently seen being cleaned. A series of these 

 males were collected both in and out of the re- 

 productive season, and the numbers of ectopar- 

 asites they carried were assessed. Seven indi- 

 viduals (mean length 228 mm) sampled as they 

 guarded their eggs carried a mean of 67 Caligus 

 hobsoni (range 20-144), 2.5 Lepeophtheinis sp., 

 1.4 gnathiid isopod larvae, and 0.2 monogenetic 

 trematodes. These counts contrast strikingly 

 with those from six males (mean length 219 mn\) 

 sampled outside the reproductive season, which 

 carried a mean of only 4.8 C. hobsoiii (range 

 0-13), 1 Lepeophtheinis sp., 0.8 gnathiid larvae, 

 and no monogenetic trematodes. These findings 

 suggest that males which are guarding eggs be- 

 come heavily infested with C. hobsoni when they 

 do not allow cleaners to approach them, a con- 

 clusion strengthened by the fact that over this 

 same period the relative numbers of this same 

 ]"iarasite were not noted to change on other in- 



fested fishes. The samples included too few of 

 the other parasites to make a meaningful com- 

 parison. It remains a question why Lepeoph- 

 theinis sp. and the gnathiid larvae did not show 

 a pattern of occurrence similar to that of C. 

 hobsoni, as both of these parasites are known 

 to be prey of the cleaners. In any event, these 

 data add to the evidence which indicates that 

 C. hobsoni is the primary prey of cleaning sen- 

 oritas in the study areas. 



Ectoparasites on Senoritas 



Senoritas that were closely observed as they 

 cleaned other fishes often were noted to have 

 caligid copepods on their bodies. One seiiorita, 

 about 120 mm long, was host to an estimated 

 100 of these parasites concentrated especially 

 along the dorsal-fin base. These observations 

 were significant because during the survey for 

 ectoparasites, most seiioritas taken from the pop- 

 ulation at large were free of external forms, 

 although many carried a chondracanthid cope- 

 pod on their gills. 



Twenty seiioritas, 102 to 190 mm long, were 

 sampled from among those giving no indication 

 of being cleaners. Eight of these carried 1 or 

 more of the chondracanthids on their gills, but 

 only 2, or 10''r, had parasites on their external 

 body surfaces: one of these carried 10 speci- 

 mens of Caligus hobsoni and 1 specimen of 



Table 3. — Hosts of Caligus hobsoni. 



Species 



Specimens 

 examined 



Specimens 



hosting 

 C. hobsoni 



Number of 



C. hobsoni 



on eoch 



infested fish 



mean (range) 



Percent 

 occur- 

 renca 



Blacksmith, Chromis punctipinni! 

 Topsmelt, Jthfrinops affinis 

 Gofiboldi, Hypsypops rubicunda 

 Halfmoon, Mediatuna calijorniensis 

 Opaleye, Girella nigricans 

 Olive rockfish, Sfbastes serranoides 

 Blue rockfish, Sebastes mystinus 

 Sharpnose seaperch, Phanerodon atripf: 

 Senorita, Oxyiulis catiiornica 

 Sheephead, Pimetometopon pulchrum 

 Rubberlip perch, Rhacotkilus toxoids 

 Cobezon, Scorpaenichthys marmoratus 

 Gopher rockfish, Sfbaslc-s carnalus 

 Pile perch, Rhacochiius vacca 

 Kelp rockfish, Sehastfs atroi'irfns 



* .Ith^rinops affinii does not carry C. hobsoni. 

 text) of the very similar C. serratus. 



but rather is the sole host (with one exception, see 



509 



