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Fishery Bulletin 1 14(3) 
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Figure 3 
Representative examples of images from the database of photographs from the 2011 survey 
of sea scallops (Placopecten magellanicus) in the Long Island and New York Bight areas. 
The sea bottom was photographed with an underwater camera mounted inside the nose cone 
of an autonomous underwater vehicle. Images A, C, D, and E show sea scallops resting on 
the seafloor. Images B and F show other species incidentally photographed during the AUV 
surveys including crabs, fish, and skates. 
on-the-ground length represented by the pixels was 
then calculated from the metadata of each image 
(e.g., altitude, pitch, and camera FOV) with Equa- 
tion 1. 
4 Shell height was not recorded if more than half 
of the entire scallop was not contained within the 
frame. 
5 Scallops identified as disarticulated shells were nei- 
ther counted nor sized. 
6 The final count for a survey was the number of scal- 
lops that could be sized. 
Scallop densities were calculated for each survey 
site. The number of scallops that were identified and 
sized for each survey were summed and divided by the 
area of the seafloor that had been photographed. In or- 
der to limit the effect of image overlap (as much as 5% 
in the current surveys), the AUV transect length was 
calculated from the global positioning system (GPS) 
start and end point of each survey line. The transect 
length was then multiplied by the mean image width 
for that transect, and the vehicle control kept the AUV 
to v/ithin 16 cm standard deviation of the 2.2 m alti- 
