Jackson Estuarine Laboratory

Ecological studies of the salt marsh ecad scorpioides (Hornemann) Hauck of Ascophyllum nodosum (L.) Le Jolis


The seasonal and spatial distribution of the free-living ecad scorpioides (Hornemann) Hauck of Ascophyllum nodosum (L.) Le Jolis are described from the Great Bay Estuary System of New Hampshire-Maine, U.S.A. The growth and distribution of ecad scorpioides show a variety of phenological and distributional relationships between A. nodosum and the marsh grass Spartina alterniflora Loiseleur-Deslongchamps. A biomass maximum of ecad scorpioides was found in the fall during two consecutive years; it may be attributable to an influx of source material (i.e., A. nodosum) after storms, as well as normal seasonal growth of the ecad. Spartina alterniflora provides initial stability for the progenitor fragments of ecad scorpioides and a protective canopy during the summer. Sexual reproduction of the ecad scorpioides was only recorded during one of the three years of study. The morphology and reproduction of ecad scorpioides is compared and contrasted with the attached A. nodosum, as well as with several detached ecads. A gradient of morphology is evident from typical A. nodosum to the extreme ‘marsh’ ecad scorpioides.

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Journal of Experimental Marine Biology and Ecology

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Copyright © 1976 Published by Elsevier B.V.