2012 COURSE DATES: AUGUST 4 – 17, 2012 - Sirenian International

798 Fish Sci (2011) 77:795–798
nets, the animals often explore the ‘‘weak areas’’ of the net
via tactile contact in order to escape (Olivera-Gomez LD,
2011, pers. comm.). They tend to descend to the bottom of
the net and pull it up with its snout. There are many reports
of these escape behaviors by local fishermen. Wild Antillean
manatees can escape from the net in this way, and this
more often occurs at deeper depths, where the net is more
vertical (Olivera-Gomez LD, 2011, pers. comm.). In shallow
depths, where the net forms a bag, manatees enter the
fold of the net and are more easily caught on it (Olivera-
Gomez LD, 2011, pers. comm.). In addition, entanglement
often occurs with larger mesh size nets, which are used to
catch large fishes (Olivera-Gomez LD, 2011, pers. comm.).
Therefore, we further recommend examining the position
of the net relative to the depth and the effect of the mesh
size in order to clarify the causes of manatee entanglement.
Acknowledgments We would like to thank all of the staff at the
Okinawa Churaumi Aquarium for their assistance in conducting these
experiments. We would like to thank K. Asahina at Nihon University,
H. Kato at Tokyo University of Marine Science and Technology, L.
D. Olivera-Gomez at the Autonomous University Juarez of Tabasco,
and D. Gonzalez-Socoloske at Duke University for their discussions
and insightful comments on previous drafts. We also thank J.
A. Mobley and D. Gonzalez-Socoloske for correcting the English
manuscript. The present study was supported by the Fisheries
Research Agency, National Research Institute of Far Seas Fisheries.
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