Behavioral impacts of disentanglement of a right whale under sedation and the energetic cost of entanglement
Protracted entanglement in fishing gear often leads to emaciation through reduced mobility and foraging ability, and energy budget depletion from the added drag of towing gear for months or years. We examined changes in kinematics of a tagged entangled North Atlantic right whale (Eg 3911), before, during, and after disentanglement on 15 January 2011. To calculate the additional drag forces and energetic demand associated with various gear configurations, we towed three sets of gear attached to a load-cell tensiometer at multiple speeds. Tag analyses revealed significant increases in dive depth and duration; ascent, descent and fluke stroke rates; and decreases in root mean square fluke amplitude (a proxy for thrust) following disentanglement. Conservative drag coefficients while entangled in all gear configurations (mean ± SD Cd,e,go = 3.4 × 10-3 ± 0.0003, Cd,e,gb = 3.7 × 10-3 ± 0.0003, Cd,e,sl = 3.8 × 10-3 ± 0.0004) were significantly greater than in the nonentangled case (Cd,n = 3.2 × 10-3 ± 0.0003; P = 0.0156, 0.0312, 0.0078, respectively). Increases in total power input (including standard metabolism) over the nonentangled condition ranged from 1.6% to 120.9% for all gear configurations tested; locomotory power requirements increased 60.0%-164.6%. These results highlight significant alteration to swimming patterns, and the magnitude of energy depletion in a chronically entangled whale. © 2013 Society for Marine Mammalogy.
Duke Scholars
Altmetric Attention Stats
Dimensions Citation Stats
Published In
DOI
EISSN
ISSN
Publication Date
Volume
Issue
Start / End Page
Related Subject Headings
- Marine Biology & Hydrobiology
- 4102 Ecological applications
- 3109 Zoology
- 3103 Ecology
- 0608 Zoology
- 0603 Evolutionary Biology
- 0602 Ecology
Citation
Published In
DOI
EISSN
ISSN
Publication Date
Volume
Issue
Start / End Page
Related Subject Headings
- Marine Biology & Hydrobiology
- 4102 Ecological applications
- 3109 Zoology
- 3103 Ecology
- 0608 Zoology
- 0603 Evolutionary Biology
- 0602 Ecology