Sponge Morphology and Filter Feeding Efficiency in Haliclona ecbasis, Ophlitaspongia pennata, and Mycale hispida.

Abstract

Filter feeding of microalgae is known to be a source of nutrients in sponges, but the relationship between sponge morphology and filter feeding rates have not been investigated. The demosponges Haliclona ecbasis, Ophlitaspongia pennata, and Mycale hispida of class Demospongiae are commonly found in the San Juan Islands, and were used in a comparison study of sponge morphology and filter feeding rates. Sponge samples were collected from two sites, one intertidal and one subtidal, and were treated with a microalgae monoculture of Nannochloropsis. Water samples were taken at regular intervals and measured by spectrophotometer at λ 440nm for absorbance. Post ANOVA statistical analysis samples from the intertidal site were found to not show any variance within species at any collection point. Specimens from the subtidal site failed to produce conclusive data possibly due to contamination of sponges by other organisms inhabiting the sponges or weakness in the methodology. Therefore, the results of this study conclude that the three species Haliclona ecbasis, Ophlitaspongia pennata, and Mycale hispida of class Demospongiae may not have significantly different filter feeding efficiencies even though each species exhibit different morphotypes.