Transplantation of seagrasses, with special emphasis on eelgrass, <i>Zostera marina</i> L.

A background, listing the history of transplanting seagrasses is given. There is a need for seagrass field planting methods owing to the extremely high productivity of seagrasses and the perturbations they are subjected to. I have planted vegetative stocks and seeds of Zostera marina L. (eelgrass) across tidal zones, across latitudinal zones (from Alaska into Puget Sound), and into water deeper than indigenous growth. Data from these plantings indicate: (1) varietal distinctions based on leaf dimensions are invalid; (2) the possibility of local physiological race distinction in eelgrass; (3) the depth limit of eelgrass is due to a lack of suitable light deeper than a certain minimum depth; and (4) eelgrass seedlings require a higher light intensity than is present deeper than a certain minimum depth. Thus, transplanting experiments yield much more data concerning seagrass biology than just planting method information.