MAYNARD ET AL.: HAWAIIAN MESOPELAGIC MICRONEKTON 



300 -I 1 1 1 ' L 



250 - 



u 



a. 



u. 

 (C 



z 

 <r 



(_) 

 o 



o 

 o 



z: 

 cr 



IT 



200 - 



150 - 



* 100 

 cr 



50 - 



TIME: 0600 



r 



HflUL: 187 



I 1 — 



0800 1000 1200 



T T t 

 188 189 190 



1 1 



1400 1600 1800 2000 2200 2400 0200 



t t T t t r t t 



191 192 193 194 195 196 197 198 



CEPHRLOPODfl 



-n \ K 



0400 0600 

 r t 



199 200 



Figure 5.— Shallow-tow (0-400 m) standing stock of micronekton biomass (wet weight) over 24 h. Time is plotted for midpoint of each 



tow. 



the numbers and especially biomass. In addition, 

 pooling species into the 16 groups of Table 3 

 sometimes lumps vertical migrators with non- 

 migrators, and primary carnivores with higher 

 predators, blurring a precise ecological definition 

 for a group. We feel, however, that our groups are 

 adequate for a first overview of the micronekton 

 fauna off Hawaii. 



Our data may not represent standing stocks 

 characteristic of the open ocean, and the pos- 

 sibility of an island effect should be considered. 

 Oahu affects surface circulation up to 1,500 km 

 downstream (Barkley 1971), but effects on plank- 

 ton and micronekton standing stocks are not clear. 

 An island mass effect has been observed off Oahu 

 for phytoplankton (Gilmartin and Revelante 

 1974). King and Hida (1954, 1957a, b) found little 



correlation between distance from Oahu and 

 zooplankton standing stock, whereas other 

 workers have found a decreasing standing stock 

 with increasing distance from the island (Sette 

 1955; McGary 1955; Doty and Oguri 1956). 

 Nakamura (1967) could detect no differences in 

 mean zooplankton standing stock between wind- 

 ward and leeward Oahu samples, but windward 

 samples consistently contained more decapods. 

 We are not certain what island effects, if any, 

 influence the leeward Oahu micronekton other 

 than the occasional occurrence of some larvae of 

 reef and benthic animals (e.g., stomatopods, crabs, 

 fishes) which fall into the size range of micronek- 

 ton as defined here. 



Temporal fluctuations in micronekton standing 

 stock pose an important caveat in evaluating our 



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