Bacterial growth rates and bacterivory around the Galápagos Islands

Abstract

The equatorial Pacific is an HNLC (high-nitrate, low chlorophyll) region, with the exception of the area around the Galápagos Islands, where there is commonly a relatively large standing stock of phytoplankton. In this experiment, the growth rates of bacteria and the grazing rates of the organisms that feed on bacteria were measured at two stations around the Galápagos, one thought to have higher iron concentrations than the other. It was predicted that when iron was added to water samples from east of Isabela island, a large increase in growth rate would be seen, because it usually has less phytoplankton, presumably due to having less iron.