Juvenile Trawl Survey

In addition to the Ecological Monitoring Trawl Survey (EMTS), the Department also conducts a Juvenile Trawl Survey (JTS). This sampling effort, first conducted from 1977-1985 and re-initiated in 2006, is designed to characterize, quantify, and assess juvenile and sub-adult finfish and crustacean populations occurring in smaller rivers, creeks, and sounds. Utilizing an otter trawl configured with a naked (i.e. no BRD or TED) 20’ semi-balloon net, CRD personnel conduct sampling monthly in two of Georgia’s estuaries: Ossabaw and Altamaha. Six fixed stations located in the creeks/rivers sector are sampled in each estuary. Biological information, including total weights, lengths of up to 30 individuals per species, and total number of individuals observed are collected for each species. At each station, GPS coordinates, tow duration and speed, depth, and tide information are recorded, as are hydrological data (water temperature, salinity, and dissolved oxygen).  

Information gathered in this survey is used to further assess species composition and abundance in areas not sampled by the EMTS survey. Data collected can be used by researchers and resource managers to answer questions regarding juvenile/sub-adult abundance, community structure, and trophic (food-chain) interactions. This pro-active sampling also provides fishery managers another tool with which to better manage and regulate marine populations.