fluke female

Female Fluke

fluke male

Male Fluke

Fluke Sex-Ratio Study

Cornell Cooperative Extension of Suffolk County (CCE) in conjunction with the Partnership for Mid-Atlantic Fisheries Science (PMAFS) is conducting Atlantic coast-wide research on summer flounder in support of stock assessment needs. PMAFS is a multi-state, multi-institutional partnership aimed at addressing the most urgent scientific problems in fisheries management and incorporating critical information into the management process through its partnerships with NMFS, MAFMC and ASMFC. Summer flounder is an important commercial and recreational fishery along the northeast coast of the United States from North Carolina to Massachusetts, and the stock is currently in need of a more detailed assessment.

Our project is aimed at providing sex-ratio data to include in current stock estimations of summer flounder. Presently, no such data exists. Male and female summer flounder develop differently and are therefore characterized by different natural mortality rates. CCE technicians conduct biological sampling of summer flounder in the recreational and commercial fishing industries in New York, Rhode Island, Connecticut and Massachusetts to obtain data relative to these differences.

Fieldwork involves recording the sex, length and weight frequencies of fish along with removing hard parts such as otoliths (fish ear bones) and scales for age determination. The otoliths can be extracted through the gills for commercially landed fish or by cutting into the skull in the case of recreationally landed fish. The collection of otoliths and the proportion at sex will help to provide a better indicator of stock productivity. Once hard parts and biological information is collected, age structures are further analyzed at the Northeast Fisheries Science Center in Woods Hole, Massachusetts.

Female Male

fluke female

fluke male

Continuous cooperation from both recreational and commercial fishermen, seafood dealers and industry members has enabled CCE technicians to gather raw data on over 9,250 fish to date. New York ports include; Captree, East Hampton, Freeport, Hampton Bays, Huntington, Mastic, Mattituck, Montauk, Moriches, Point Lookout, Sheepshead Bay and Port Jefferson. Ports sampled throughout Southern New England include; Niantic and Stonington in Connecticut, Point Judith and Snug Harbor in Rhode Island, and Westbrook, New Bedford, Hyannis in Massachusetts.

CCE is dedicated to addressing the needs of fishing communities and industries both locally on Long Island and in other states.

Thank you to all fishermen who participated in the 2010 sampling efforts!


Darci Bielenda
Marine Program Sr. Administrative Assistant SCMELC
631-852-8660 ext. 21

Last updated July 26, 2019