Stable isotope ratios of model meso- and bathypelagic micronekton species of the Gulf of Mexico, cruises DP01, DP02, LF2015A and LF2015B from May 2015 - August 2015

Stable isotope analyses will be collected from model species in order to provide information on the trophic connectivity of the ecosystem. During epi-, meso- and bathypelagic sampling (both primary cruise and Texas A&M University [TAMU] ichthyoplankton surveys), specimens of target organisms, ranging from plankton to fishes and invertebrates will be frozen at sea and analyzed to characterize and quantify food web dynamics in the Gulf of Mexico. Key model species will include both vertically migratory and non-migratory fish and invertebrate species with multiple feeding strategies including planktivores, zooplanktivores, gelativores, and piscivores. Target species displaying strong diel vertical migration include Sigmops elongatus and Ceratoscopelus warmingii, versus species showing no or asynchronous vertical migration, such as Argyropelecus hemigymnus and Cyclothone obscurai. Data will be used to evaluate food web structure, examine flow of organic matter and determine trophic relationships by analyzing the tissues of target organisms.