Dataset: Field conditions during grazing experiments in Kaneohe Bay, HI during 2012-2013 (EAGER: Copepod nauplii project)

Five combined bottle incubation and seawater dilution experiments were performed over a two-week period where the in-situ 2-35 µm total cell biomass ranged from 37 – 158 µg C L-1. Both Parvocalanus crassirostris and Bestiolina similis grazed a range of prey types and sizes, and shifted their selectivity of prey groups over the two-week period. In general, P. crassirostris grazed on a wider spectrum of prey than B. similis, which avoided the smallest potential prey (2-5 µm) across all dates. Both species had similar overall grazing rates as well as high daily carbon rations (at times >100%), and selected for the largest cells when they were more abundant. The trophic impact of each species was driven largely by in situ nauplius abundance, which was higher for P. crassirostris, from 0.8 to 8.9 nauplii L-1, than for B. similis, which ranged from 0.2 to 0.8 nauplii L-1.  Our results suggest that the two species overlap in their potential prey, however, P. crassirostris appears to target a wider variety of prey, with B. similis preferring larger cells.