FISHERY BULLETIN: VOL. 70, NO. 4 



episode involving a member of this family. 

 Breder (1962) noted a single juvenile Lagodon 

 rhomboides picking at the pelvic axils of three 

 successive Mugil cephalus in Lemon Bay, Fla, 

 Breder commented that this was the only time 

 he had observed this interaction although he was 

 thoroughly familiar with both species. 



Our analyses of stomach contents of juvenile 

 D. holbrooki (11 to 80 mm, see Figure 2) show 

 clearly that this species, like 0. sauriis, goes 

 through a stage in the initial year of its devel- 

 opment in which cleaning behavior is implicated. 

 Concurrent analyses of more than 3,000 stom- 

 achs of juveniles of another sparid, Lagodon 

 rhomboides (10 to 130 mm), collected from the 

 same area failed to yield a single ectoparasite 

 or other evidence of cleaning activity in this re- 

 lated species. Data on food habits of L. rhom- 

 boides and juveniles of other species in our study 

 area will be published at a later date. 



It is noteworthy that, in juveniles of both D. 

 holbrooki and 0. saurus, fishes in the size range 

 of 26 to 40 mm are the ones in which ectopara- 

 sites make their maximum contribution to the 

 diet. Likewise, ectoparasites become markedly 

 less important in the diets of slightly larger in- 

 dividuals thereby strongly implying that the 

 cleaning habit is confined to only a portion of 

 the total juvenile, phase of development in both 

 species. Although our data show that the diet 

 of juvenile 0. saurus includes proportionately 

 greater amounts of material obtained from 

 cleaning activities than the diet of juvenile D. 

 holbrooki, it is clear that neither species depends 

 exclusively on this activity. Limbaugh (1961) 

 has previously reported that some species are 

 cleaners only as juveniles and that few cleaners 

 depend exclusively on this habit as a source of 

 food. 



Our analyses of stomach contents of D. hoU 

 hrooki show that after reaching a length of 26 

 to 30 mm, this species becomes very dependent 

 on plant material in the form of epiphytic algae. 

 Reid (1954) found algae as well as other items 

 in the stomachs of D. holbrooki from Cedar Key, 

 Fla.; however, neither the size of the individuals 

 analyzed nor any sort of quantitative informa- 

 tion was reported. The study of Caldwell (1955) 

 on this species from the same area included no 



information on stomach contents. Randall 

 (1967) has reported that the diet of the closely 

 related species, D. caudiviacula, from the West 

 Indies is approximately 80% algae, thereby 

 making it quite similar in this regard to our 

 findings with D. holbrooki. 



Although our studies on fishes, collected in the 

 field and obtained from museum collections, 

 show clearly that juveniles of both 0. saurus and 

 D. holbrooki are cleaners, attempts to observe 

 cleaning behavior in the field have been unsuc- 

 cessful. The estuarine water in our study area 

 is too turbid to permit underwater observations 

 of the behavior of small fish at a distance. Aside 

 from the excellent studies of Limbaugh (1964) 

 and Hobson (1971) on cleaning symbiosis 

 among inshore fishes of southern California, 

 there have been few reports on visual observa- 

 tions of cleaning behavior by fishes in waters 

 of the Temperate Zone. McCutcheon and Mc- 

 Cutcheon (1964) alluded to the fact that water 

 conditions in the Temperate Zone are frequently 

 less favorable than those in the tropics where 

 many detailed descriptions of cleaning symbiosis 

 have been made. On two occasions, we observed 

 groups of pinfish (Lagodon rhomboides) in our 

 study area behaving in a manner suggestive of 

 that described for groups of blacksmith {Chrom- 

 is punctipinnis) when presenting themselves to 

 a cleaner (Limbaugh, 1964; Feder, 1966; and 

 Hobson, 1971). On both occasions, a group of 

 several dozen subadult pinfish were seen milling 

 about in a tight circle just beneath the surface 

 in water approximately 6 ft deep. Pinfish are 

 normally bottom dwellers, and the sight of a 

 large group near the surface behaving as de- 

 scribed above was extremely unusual. Although 

 sizable numbers of juvenile D. holbrooki were 

 seen swimming back and forth in the vicinity 

 of the pinfish, poor visibility made it impossible 

 to determine whether the pinfish were being 

 cleaned. Juvenile Diplodus collected from this 

 same area at this time were found to have ecto- 

 parasites (primsLri]y Argulus) in their stomachs. 

 In addition, it may be noteworthy that juveniles 

 of D. holbrooki and of L. rhomboides, both spar- 

 ids, are frequently seen swimming together in 

 small mixed schools. 



Although no observations have been made of 



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