The smaller sharks that were brought aboard live were tagged with a code number and contact number if they were ever caught, it went thru their dorsal fin and they were injected with a little tetracycline anti-biotic that has a weird side effect of staining a ring in their vertabrae (tetracyline will do this with teeth too if it is taken too long or given to kids, ewww) and if they are caught later the line of yellow in the carilage would show how much they have grown since the original time they were caught. Their gender, stage of sexual development and size were all documented before they were re released. The larger sharks recieved a satilite tag in addition to the injection to document their movements. The locations the boat fished at were computer generated at random to give a representation of what all resided in various parts of the gulf, not just known fishing spots. We also caught a good amount of grouper and snapper and a few other species of fish. If they were dead we would remove the gonads, otoliths (little bone in the skull that can be used to determine age) and skin samples for analysis. The dead sharks brought aboard had their gonads, livers, blood and skin were anaylzed and studied. The data collected is used for various studies, health of a specific species, to determine their life cycles, migration and population health. It was a NOAA research vessel but the information collected was shared with scientists and other departments. We also had a device that was set down at every station that took every possible environmental factor, salinity, temp, turbity etc etc… lots of environmental evaluations