Rank 



FISHERY BULLETIN: VOL. 71, NO. 3 

 Table 1. — Gut contents of 64 silversides collected on 23 and 24 March 1972. 



Size (mm) 



Item 



Mean 



Range 



1 



2 



3 



4 



5 



6 



7 



8 



9 



10 



11 



12 



13 



14 



15 



16 



17 



Gut contents of 31 silversides 35 to 67 mm long, collected on 23 March 1972 



Hyperia bengalensis (hyperiid amphipod) 



Tretomphalus stage of foraminiferan(s) 



Caridean shrimp larvae 



Myodocopid ostracods 



Undimila vulj^aris (calanoid copepod) 



Crab megalops 



Lucifer (sergestid shrimp) 



Candacia discaudata (calanoid copepod) 



Insects 



Mysids 



Veliger larvoe (mollusks) 



Zoea larvae (crabs) 



"Other" calanoid copepods 



Polychaetes 



Saphirella sp. (cyclopoid copepod) 



Oncuea sp. (cyclopoid copepod) 



Larvaceans 



Also, unid. amorphous mroterial 



Gut contents of 33 silversides 35 to 69 mm long, collected on 24 March 1972 



1 Hyperici hennalensis ((hyperiid amphipod) 



2 Myodocopid ostracods 



3 Tretomphalus stage of foraminiferan(s) 



4 Candacia discaudata (calanoid copepod) 



5 Caridean shrimp larvae 



6 Undinula vulgaris (calanoid copepod) 



7 Mysids 



8 "Other" calanoid copepods 



9 Insects 



10 Veliger larvae (mollusks) 



1 1 Polychaetes 



12 Lahidocera acuta (calanoid copepod) 



13 Lucifer (sergestid shrimp) 



14 Crab megalops 



15 Oiuaea sp. (cyclopoid copepod) 



16 Saphirella sp. (cyclopoid copepod) 



17 Stomatopod larvae 



18 Alphaeid shrimp 



19 Zoea larvae (crabs) 



20 Gammarid amphipods 



21 Globigerina sp. (foraminiferan) 

 Also, unid. amorphous material 



unid. crustacean fragments 



>0.50 was considered to be 0.75, and <0.50 

 was considered to be 0.25. 



A few forms predominated in the silverside 

 diet when these observations were made. The 

 hyperiid amphipod Hyperia bengalensis was 

 especially important, with other major prey 

 including: the tretomphalus stage of a foram- 

 iniferan(s); myodocopid ostracods; caridean 

 shrimp larvae; and two calanoid copepods: 

 Candacia discaudata and Uitdiiiula nilgaris. 

 These forms constituted over 90% of the food in 

 the guts of the silverside that were sampled. 



PLANKTON AS PREY FOR 

 THE SILVERSIDE 



To determine whether these forms were 

 selected by the silverside or were taken only in 

 numbers relative to their abundance in the 

 plankton, net hauls were made concurrently 

 with the fish collections. The i)lankton sampled 

 were from the lagoon between 22 and 24 March 

 1972. Additional plankton collections were 

 made in the same location during daylight, thus 



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