Importance of zooplankton to platform productivity

Abstract

The source of productivity that sustains the high numbers of fishes associated with petroleum
platforms remains a poorly understood question. Recent studies on the feeding ecology of blue
runner Caranx crysos suggest that zooplankton form a substantial portion of the diet during earlymid
summer. The dominant zooplarikton in the diets of these highly abundant fishes are
predominantly pelagic marine taxa. We suggest that the combination of artificial illumination and
modification of the hydro dynamic flow field by the platform structure favor the accumulation of
large numbers of oceanic zooplankton. The artificial illumination also allows nocturnal feeding by
visual predators such as blue runner. This subsidy of zooplankton may provide an important link in
the food web at offshore platforms.