“…During this season, the water column stratification results in a two-layered euphotic zone (Coale and Bruland, 1987), with the upper layer being nutrient limited and the lower layer being light limited (Mignot et al, 2014). Regardless of the general oligotrophic condition in this region, many studies have described a surprising diversity and biomass of higher trophic level communities (Alemany et al, 2006; Rodriguez et al, 2013; Fernández de Puelles et al, 2014; Hidalgo et al, 2014; Laiz-Carrión et al, 2015; Reglero et al, 2017), often utilizing chlorophyll- a (Chl- a ) or fluorescence estimates as a proxy for primary production biomass to assess food web linkages of many marine species. However, the relation between carbon biomass (C) and Chl- a concentration (C:Chl- a ) in phytoplankton cells is largely variable and is influenced by light, nutrients and temperature (Jakobsen and Markager, 2016).…”