Photosensitivity of the calanoid copepod Acartia tonsa


Journal Article

The light intensity and spectral sensitivities of the calanoid copepod Acartia tonsa Dana were determined by measuring phototactic responses. Adult females displayed only positive phototaxis. The dark-adapted copepod, which possesses a single naupliar eye, perceived light at intensities as low as 2.8x1011 photons m-2 s-1. The action spectrum for positive phototaxis had no clear maxima but rather showed a broad range of greatest sensitivity from 453 to 620 nm. This sensitivity encompassed those wavelengths that are maximally available at the depth where the copepod is found during the day. This spectral overlap, coupled with the finding that the copepod requires light cues for nocturnal vertical miration, suggests that broad spectral sensitivity is an adaptive mechanism to maximize light intensity sensitivity during migration. © 1984 Springer-Verlag.

Full Text

Duke Authors

Cited Authors

  • Stearns, DE; Forward, RB

Published Date

  • August 1, 1984

Published In

Volume / Issue

  • 82 / 1

Start / End Page

  • 85 - 89

Electronic International Standard Serial Number (EISSN)

  • 1432-1793

International Standard Serial Number (ISSN)

  • 0025-3162

Digital Object Identifier (DOI)

  • 10.1007/BF00392766

Citation Source

  • Scopus