Lutcavage et al.: Aerial survey of Thunnus thynnus in the Straits of Florida 
301 
Figure 1 
View of the study region showing the location of “Tuna Alley” along the western margin of the 
Great Bahama Bank, Straits of Florida. 
wind direction, lunar phase, and tide. He tentatively 
concluded that the difference in magnitude of the an- 
nual population estimates might be attributed to dif- 
ferences in wind speed across Tuna Alley and, conse- 
quently, to changes in the visibility of bluefin tuna 
to aircraft and fishing vessels. 
The decline of North Atlantic bluefin tuna stocks 
since the 1970’s has heightened efforts to obtain more 
accurate indices of abundance, particularly for 
spawning biomass. Despite documented changes in 
bluefin tuna stocks and commercial fishing practices, 
there have been no aerial surveys or direct assess- 
ments of giant bluefin tuna transiting the Great 
Bahama Bank for over 20 years. From 19 May to 9 
June 1995, we conducted an aerial survey of giant 
bluefin tuna transiting the Great Bahama Bank re- 
gion in the general vicinity of the Bimini islands and 
sand cays. Our objectives were to document their 
apparent abundance and behavior and to compare 
the results of the present study with those obtained 
