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Adult Red Drum and Shark Longline Survey
Adult Red Drum Longline SurveyThe adult red drum survey began in 2006. The main purpose of the study is to determine annual abundance estimates for the offshore component of red drum. The survey has been a pilot survey to date and has examined the effects of bait type and hook size on species selectivity as well as examining spatial and temporal effects on catch rates. The survey also produces abundance estimates for sharks species found offshore. Sampling occurs from April through the end of December in coastal waters out to 12 n.mi., extending from the mouth of Doboy Sound, GA to the mouth of St. Johns River, FL. A bottom-set, hydraulically retrieved longline is deployed from the R/VMarguerite, a 47’ offshore vessel. The mainline is made of 600 lb. monofilament and is approx. ½ mile in length. A total of 60 droplines comprised of a longline snap, 0.5 m of 200 lb. monofilament and either a 12/0 or 16/0 circle hook on the terminal end. Hooks are not offset and have barbs depressed. The total soak time is 30 minutes and squid is used for bait. Monthly sampling includes a maximum of 35 random stations; 25 in waters off Georgia, 10 in waters off Florida. The survey has been successful at capturing red drum and has caught 14 shark species, four of which are common (Atlantic sharpnose shark, blacknose shark, bonnethead, blacktip shark).
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