Evaluation of Summer Flounder Discard Mortality in the Bottom Trawl Fishery

Project Description

The present summer flounder (fluke) Fishery Management Plan assumes an 80 percent discard mortality.  Fishery managers and fishermen share a concern over the use of an arbitrary discard mortality rate.  Cornell Cooperative Extension's (CCE) Marine Program, with the involvement of local commercial fishermen, is currently conducting trawl surveys to determine actual fluke discard mortality. While determining fluke discard mortality is the primary purpose of this study, fishing and on-board practices are being identified which may enhance fluke discard survival.  


Participating commercial draggers conduct one-day fishing trips in the in-shore mixed trawl fishery.  Each trip consists of three tows; one, two and three hours each.  On-board CCE staff conducts immediate and delayed (30 minute) culls of legal and sub-legal sized fluke. Sampled fish are evaluated for condition, weighed, measured and tagged using different colors for different tows and cull times.  Selected fish are maintained in on-board live holding tanks.  The remainder of the catch is sorted by species and weighed.


These 120 fish, along with 20 trap-caught control fish are being held for 14 days in a specifically designed net pen located at Inlet Seafood dock in Montauk, NY. Fish are monitored during captivity for mortality every other day. Staff uses a hookah rig to dive and retrieve dead fish from the pen. Tag information is recorded from these dead fish and scale samples as well as otoliths are collected.


Staff also take blood samples of a  representative number of fish just prior to their release after 14 days in captivity.   The blood is then analyzed for cortisol levels as an additional indicator of fish health and condition. Blood is also drawn from non-sample fish onboard the boat.


At the end of 14 days the remaining fish are evaluated for physical condition and released. We are currently seeking information from these tagged fish that have been released. The releases will continue until November 2007. There is a $20 reward for each tag reported with tag number, color, location caught, size and weight of the fish and water depth. Please report all tags!



NMFS RSA Program


Cornell Cooperative Extension of Suffolk County—

Marine Program (CCE)


Rutgers University—Haskin Shellfish Research Laboratory


The Long Island Commercial Fishing Association (LICFA) 


Mid-Atlantic Fishery Management Council (MAFMC)


Montauk Inlet Seafood, Inc.—Montauk, NY