IIOBSON; CLEANING SYMBIOSIS 



2.4';. A number of items each made up less 

 than l''f of the sample, incUidinp: crab frag- 

 ments, gastropod moUusks, pycnogonids, and a 

 gnathiid isopod larva. Unidentified material 

 constituted le^r of the sample. The gnathiid 

 larva, a single individual from one seiiorita, was 

 the only evidence of ectroparasites among this 

 material. 



Limbaugh (195.^)) stated that senoritas are 

 omnivorous carnivores which feed on almost any 

 animal material. Quast (1968) concluded that 

 the principal foods of the seiiorita are small 

 gastropods and crustaceans associated with al- 

 gae. Because he found no crabs or pistal shrimps 

 in the diet, Quast suggested that bottom feeding 

 is infrequent; however, having seen senoritas 

 frequently picking on the bottom, I believe there 

 must be some other reason why these prey are 

 not taken more often. Size may be a factor, as 

 crabs and pistal shrimps generally are larger and 

 more heavily shelled than most prey of the 

 seiiorita. 



Movements. — Although individual seiioritas 

 may range widely over the bottom in a given 

 locality, they seem to operate within a restricted 

 range. Individual fish, when followed, always 

 criss-cross back and forth within a defined area. 

 Twelve individuals, selected randomly from the 

 population at large and kept under surveillance 

 for 11 to 15 min each, showed no evidence of 

 cleaning. 



Senoritas are most abundant at the 3- to 10-m 

 station and become progressively fewer with in- 

 creasing depth offshore. Nevertheless, even at 

 the 30- to 35-m station the species was among 

 the most numerous present. Fluctuations in 

 numbers wei'e often apparent with changes in 

 water temperature. Some of the movement is 

 vertical. When a layer of colder water moved 

 in over the bottom — a frequent phenomenon at 

 the 20- to 2.')-m station — seiioritas were especially 

 abundant up in the water column above the 

 thermal interface. Seasonal and other longer 

 term changes may induce inshore/offshore move- 

 ments in certain members of the popuk\tion. The 

 numbers present fall off noticeably when temper- 

 atures drop much below 13° C, but at least some 

 .senoritas were present no matter what the con- 



ditions. These comments on temperature effects 

 are based entirely on casual evaluations of rel- 

 ative abundance under varying conditions. 



Sharpnose Seaperch 



The sharpnose seaperch is not regarded as a 

 common species (e.g., Limbaugh, 1955), but was 

 relatively abundant during this study over rocky 

 substrates below 20 m in the La Jolla area. It 

 grows to over 200 mm long and is recorded from 

 Bodega Bay, central California (Miller, Gotshall, 

 and Nitsos, 1965), south to the San Benito 

 Islands, Mexico (Roedel, 1953). Most of those 

 observed during this study were juveniles less 

 than about 125 mm long that swam singly or, 

 more often, in small groups of less than 10 indi- 

 viduals. Adults were seen only occasionally but 

 sometimes swam in larger aggregations. All 

 activity observed in these fish occurred during 

 daylight. After dark they hover above the sub- 

 strate and are alert, but their activity at this 

 time, if any occurs, was not determined. 



Food habits. — This seaperch takes a variety 

 of benthic organisms from the surface of rocks, 

 algae, gorgonians, and other benthic substrates. 

 Prey are taken off the bottom in a characteristic 

 picking manner similar to that of the seiiorita. 

 However, the seaperch's dentition would seem 

 less specialized for picking than that of the 

 senorita; its conic teeth are relatively short and 

 straight, and those at the front of the jaws are 

 not notably longer than tho.se on the sides, nor 

 do they project forward. 



To investigate the food habits of this fish in 

 the study area, 13 individuals, 76 to 170 mm 

 long, were speared randomly from the popula- 

 tion at large. None of these were cleaning when 

 collected. Food items in their stomachs, ranked 

 as percentage of each item in the entire sample, 

 were as follows: caprellid amphipods, 56%; 

 chitons, 9%; planktonic copepods, 9/f ; isopods, 

 &',r ; limpets, 2%; pelycypodmollusks, 1%; and 

 sponges, l'''r. Unidentified material made up 

 14'^; of the sample. There was no evidence of 

 ectroparasites in this material. One individual 

 had fed heavily and exclusively on plankton- 

 ic copepods, showing that this fish is not 



495 



