We are pleased to announce a new publication online in Marine Mammal Science:
van der Hoop, J. M., Corkeron, P., Kenney, J., Landry, S., Morin, D., Smith, J.
and Moore, M. J. (2015), Drag from fishing gear entangling North Atlantic right
whales. Marine Mammal Science. doi: 10.1111/mms.12292
The paper is available online:
http://onlinelibrary.wiley.com/doi/10.1111/mms.12292/abstract
<http://onlinelibrary.wiley.com/doi/10.1111/mms.12292/abstract>A press release
can be found here
<http://www.whoi.edu/page/preview.do?pid=7545&tid=3622&cid=229369>.
Please contact me if you do not otherwise have access to the pdf:
[email protected] <mailto:[email protected]>
Abstract:
Lethal and sublethal fishing gear entanglement is pervasive in North Atlantic
right whales (Eubalaena glacialis). Entanglement can lead to direct injury and
is likely to incur substantial energetic costs. This study (1) evaluates drag
characteristics of entangled right whales, (2) contextualizes gear drag
measurements for individual whales, and (3) quantifies the benefits of partial
disentanglement. A load cell measured drag forces on 15 sets of fishing gear
removed from entangled right whales, a towed satellite telemetry buoy, and 200
m of polypropylene line as it was shortened to 25 m, as they were towed behind
a vessel at ~0.77, 1.3, and 2.1 m/s (~1.5, 2.5, and 4 knots) and ~0, 3, and 6 m
depth. Mean drag ranges from 8.5 N to 315 N, and can be predicted from the dry
weight or length of the gear. Combining gear drag measurements with theoretical
estimates of drag on whales’ bodies suggests that on average, entanglement
increases drag and propulsive power by 1.47 fold. Reducing trailing line length
by 75% can reduce parasitic gear drag by 85%, reinforcing current
disentanglement response practices. These drag measurement can be incorporated
into disentanglement response, serious injury determination, and evaluation of
sublethal effects on population dynamics.
Lethal and sublethal fishing gear entanglement is pervasive in North
Atlanticright whales (Eubalaena glacialis). Entanglement can lead to direct
injury and islikely to incur substantial energetic costs. This study (1)
evaluates drag characteris-tics of entangled right whales, (2) contextualizes
gear drag measurements for indi-vidual whales, and (3) quantifies the benefits of
partial disentanglement. A load cellmeasured drag forces on 15 sets of fishing
gear removed from entangled right whales,a towed satellite telemetry buoy, and
200 m of polypropylene line as it was short-ened to 25 m, as they were towed
behind a vessel at ~0.77, 1.3, and 2.1 m/s (~1.5,2.5,and4knots)and~0, 3, and 6
m depth. Mean drag ranges from 8.5 N to 315N, and can be predicted from the dry
weight or length of the gear. Combining geardrag measurements with theoretical
estimates of drag on whales’ bodies suggeststhat on average, entanglement
increases drag and propulsive power by 1.47 fold.Reducing trailing line length
by 75% can reduce parasitic gear drag by 85%, rein-forcing current
disentanglement response practices. These drag measurements can beincorporated
into disentanglement response, serious injury determination, and evalu-ation of
sublethal effects on population dynamics
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