Andre Boustany, Carol Reeb, Michael Castleton, Robert Schallert,

Michael Stokesbury, and Barbara Block

Session 1, Talk 1, 18/1/16 @ 1030 hrs

Recent advances in electronic tagging and molecular genetic technologies have shed light on the population structure and movements of bluefin tuna globally.  In the Atlantic Ocean and adjacent seas, bluefin tuna (Thunnus thynnus) spawn in the Mediterranean Sea in the east and the Gulf of Mexico/Caribbean Sea/Straits of Florida in the west.  Genetic differentiation and repeat migrations to specific spawning grounds observed in electronic tracked fish support the theory of natal homing among isolated spawning populations.  Young of the year western spawned fish travel north through the Straits of Florida where they feed for up to a decade or more along the East Coast of North America and throughout the North Atlantic Ocean, with movements varying with season and ontogeny.  At ages 10-16, these fish begin to return to the western spawning grounds during the winter and spring months.   In the Mediterranean Sea, bluefin depart though the Strait of Gibraltar during the first year of life, although a sizable portion of fish remain within the Mediterranean where they may form resident populations.  Eastern fish range throughout the North Atlantic, with major feeding grounds being found in the Bay of Biscay, along the northern edge of the Gulf Stream and off the East Coast of North America.  It is in this latter foraging area where bluefin of eastern and western origin mix most extensively, with some size classes being equal parts eastern and western in origin.

Contact:  A. Boustany, Duke University, Nicholas School of the Environment, Durham, NC, USA, This email address is being protected from spambots. You need JavaScript enabled to view it.