A study of the feeding biology of deep-sea echinoids from the North Atlantic

• Main Author: Campos-Creasey, Lúcia de Siqueira
• Format: Thesis
• Language: English
• Published: University of Southampton 1992
• Subjects: North Atlantic
• Online Access: https://eprints.soton.ac.uk/461725/; https://eprints.soton.ac.uk/461725/1/361359.pdf

The seasonal downward flux of phytodetrital material to the deep-sea floor is now becoming recognized as a significant pathway of nutrient energy to the bottom-dwelling biota. The diet of two deep-sea echinoids was investigated in order to evaluate the effect of this food input on their life history: Phormosoma placenta Wyville Thomson, a non-seasonal breeder; and Echinus affinis Mortensen, a seasonal breeder; both collected during two major deep-sea investigations including both temporal and depth related sampling programmes in the NE Atlantic. During a cruise to the Bahamas from May 25 to June 7, 1989 fresh samples of regular echinoids were also examined: Cidaris blakei , Stylocidaris lineata , Aspidodiadema jacobyi and P. placenta . Morphological observations, transmission electron microscopy and histological analysis of the gut wall, particle-size distribution and chemical analyses of the gut content were undertaken in the laboratory. The gut content of specimens of each species were identified in detail using a scanning electron microscope. Nonlinear regression and 'lack of fit' analysis have resulted in the identification of a number of seasonal fluctuations in the organ and gut content indices of both P. placenta and E. affinis (NE Atlantic).