Visual predation during springtime foraging of the North Atlantic right whale (Eubalaena glacialis)
Abstract
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 highâcontrast dark silhouette against a bright background spacelight, 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.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- May 17, 2017
- Source ID
- 10.1111/mms.12417
Entities
People
- Benjamin Nickle
- Jeffry I. Fasick
- Lorren J. Kezmoh
- Mark F. Baumgartner
- Thomas W Cronin
Organizations
- Air Force Office of Scientific Research
- Brandeis University
- National Institutes of Health
- National Science Foundation
- United States Department of Commerce
- University of Maryland, Baltimore County
- University of Tampa
- Woods Hole Oceanographic Institution