The Biological Bulletin, Vol 198, Issue 3 346-356, Copyright © 2000 by Marine Biological Laboratory

JOURNAL ARTICLE

Energetics of larval swimming and metamorphosis in four species of Bugula (Bryozoa)

DE Wendt
Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA. dewendt@uncg.edu

The amount of energy available to larvae during swimming, location of a suitable recruitment site, and metamorphosis influences the length of time they can spend in the plankton. Energetic parameters such as swimming speed, oxygen consumption during swimming and metamorphosis, and elemental carbon and nitrogen content were measured for larvae of four species of bryozoans, Bugula neritina, B. simplex, B. stolonifera, and B. turrita. The larvae of these species are aplanktotrophic with a short free-swimming phase ranging from less than one hour to a maximum of about 36 hours. There is about a fivefold difference in larval volume among the four species, which scales linearly with elemental carbon content and, presumably, with the amount of endogenous reserves available for swimming and metamorphosis. Mean larval swimming speeds (in centimeters per second) were similar among species. Specific metabolic rate and larval size were inversely related. For larvae of a given species, respiration rates remained similar for swimming and metamorphosis; however, because metamorphosis lasts about twice as long as a maximal larval swimming phase, it was more energetically demanding. Larger larvae expended more energy to complete metamorphosis than did smaller larvae, but in terms of the percentage of larval energy reserves consumed, swimming and metamorphosis were more "expensive" for smaller larvae. A comparison of the energy expended during larval swimming calculated on the basis of oxygen consumption and on the basis of elemental carbon decrease suggests that larvae of Bugula spp. may not use significant amounts of dissolved organic material (DOM) to supplement their endogenous energy reserves.

This article has been cited by other articles:

				E. T. Kosman and B. Pernet Diel Variation in the Sizes of Larvae of Bugula neritina in Field Populations Biol. Bull., February 1, 2009; 216(1): 85 - 93. [Abstract] [Full Text] [PDF]

				M. W. Jacobs, S. M. Degnan, R. Woods, E. Williams, K. E. Roper, K. Green, and B. M. Degnan The effect of larval age on morphology and gene expression during ascidian metamorphosis Integr. Comp. Biol., December 1, 2006; 46(6): 760 - 776. [Abstract] [Full Text] [PDF]

				D. J. Marshall and M. J. Keough Complex life cycles and offspring provisioning in marine invertebrates Integr. Comp. Biol., October 1, 2006; 46(5): 643 - 651. [Abstract] [Full Text] [PDF]

				D. E. Wendt and C. H. Johnson Using latent effects to determine the ecological importance of dissolved organic matter to marine invertebrates Integr. Comp. Biol., October 1, 2006; 46(5): 634 - 642. [Abstract] [Full Text] [PDF]

				A. L. Moran and D. T. Manahan Energy Metabolism During Larval Development of Green and White Abalone, Haliotis fulgens and H. sorenseni Biol. Bull., June 1, 2003; 204(3): 270 - 277. [Abstract] [Full Text] [PDF]