role of chemical and visual cues by two Sargassum shrimps in locating and selecting habitats

The Sargassum community is comprised of a unique and diverse assemblage of organisms. Habitat detection by two of the most common invertebrates, Latreutes fucorum and Leander tenuicornis , was investigated. Results of this study do not support that either L. fucorum or L. tenuicornis respond to chemical cues released by the Sargassum habitat in the absence of other information. Habitat selection of both shrimp species was examined as well. Both L. fucorum and L. tenuicornis selected live Sargassum over artificial Sargassum . Moreover, L. fucorum selected Sargassum natans over Sargassum fluitans when only visual cues were available, whereas large-sized L. tenuicornis selected S. fluitans under the same conditions. Conversely, habitat selection trials combining both chemical and visual cues resulted in no preference between the two Sargassum species by either shrimp species. Additional ecological factors that possibly influence habitat location and selection are discussed as well as the importance of Sargassum in terms of pelagic fisheries management.