Visual predation during springtime foraging of the North Atlantic right whale (Eubalaena glacialis)

• Published in: Marine Mammal Science
• Main Authors: Fasick, Jeffry I., Baumgartner, Mark F., Cronin, Thomas W., Nickle, Benjamin, Kezmoh, Lorren J.
• Format: Report
• Language: English
• Published: 2017
• Subjects: Eubalaena glacialis; Vision; Foraging ecology; Calinus finmarchicus; Downwelling irradiance spectrum; Horizontal radiance spectrum; Wilkinson; Calanus finmarchicus; North Atlantic; North Atlantic right whale
• Online Access: https://hdl.handle.net/1912/9365

Author Posting. © The Author(s), 2017. This is the author's version of the work. It is posted here under a nonexclusive, irrevocable, paid-up, worldwide license granted to WHOI. It is made available for personal use, not for redistribution. The definitive version was published in Marine Mammal Science 33 (2017): 991–1013, doi:10.1111/mms.12417. To assess the role that vision plays in the ability of the North Atlantic right whale (Eubalaena glacialis) to detect its primary prey species, the calanoid copepod Calanus finmarchicus, we have compared the absorbance spectrum of the E. glacialis rod visual pigment, the transmittance spectra of C. finmarchicus carotenoid pigments, as well as the downwelling irradiance and horizontal radiance spectra collected during springtime at three locations in the western Gulf of Maine. The E. glacialis rod visual pigment absorbs light maximally at 493 nm, while microspectrophotometric measurements of the C. finmarchicus carotenoid pigments reveal transmission spectra with minima matching very well with the E. glacialis rod visual pigment absorbance spectra maximum. Springtime spectral downwelling irradiance and horizontal radiance values from the surface waters of Cape Cod Bay and at all depths in Great South Channel overlap the E. glacialis rod absorbance spectrum, allowing C. finmarchicus to appear as a high-contrast dark silhouette against a bright background space-light, thus facilitating visually-guided contrast foraging. In contrast, spectral downwelling irradiance and horizontal radiance at depth in Cape Cod Bay, and all depths in Wilkinson Basin, do not overlap the E. glacialis rod absorbance spectrum, providing little if any useful light for contrast vision. This work was supported by Wildlife Bycatch Reduction at the New England Aquarium under U.S. Department of Commerce NOAA Award #NA09NMF4520413 (J.I.F.). T.W.C. was supported by the National Science Foundation (IOS0721608) and the Air Force Office of Scientific Research (FA9550-09-1-0149). Additional support comes ...