A Contribution to the Study of the Productivity of the Urchins Tripneustes esculentus and Lytechinus variegatus
Moore H and Mcpherson BF. 1965. A Contribution to the Study of the Productivity of the Urchins Tripneustes esculentus and Lytechinus variegatus. Bulletin of Marine Science. 15(4):855 - 871
The rates of feeding, respiration, and excretion have been determined both summer and winter for the urchins Tripneustes esculentus and Lytechinus variegatus. Both show a complete seasonal adaptation of the feeding rate to a maximum at the ambient temperature. Young individuals feed relatively three times as fast as older ones. Assimilation efficiency was about 50-60 percent in both species and showed no seasonal change. Respiratory rate was higher in summer than winter and higher, relatively, in small individuals. Both summer feeding and respiratory rates were higher in 1964 than in 1963. There was a seasonal variation in rate of excretion in Lytechinus but not in Tripneustes. Sensitivity of feeding rate to small temperature fluctuations is greater than that of respiration and is considerably greater in summer than in winter. It is suggested that depression of feeding rate in summer, in response to fluctuating ambient temperature in the shallow water may account for the observed higher growth rate of both species in cold weather.
- Type
- Journal Article
- Authors
- Moore, Hilary; Mcpherson, B
- Units
- SFCN
- Keywords
- Algae, Conditions, Diet, Factors, Food