Technical Report No. 12

THE EFFECT OF ZOSTERA JAPONICA ON THE GROWTH OF ZOSTERA MARINA IN THEIR SHARED TRANSITIONAL BOUNDARY

Glenn G. Merrill

June 1995

Bibliographic Citation
Merrill, Glenn G. 1995. The effect of Zostera japonica on the growth of Zostera marina in their shared transitional boundary. Washington State Department of Ecology (Publication No. 95-68), Padilla Bay National Estuarine Research Reserve Technical Report No. 12, Mount Vernon, Washington. 16 pp.

Abstract
A field research project was initiated during the summer of 1994, in the intertidal flats at Padilla Bay, Washington to gain preliminary information on the effect of the non-indigenous seagrass Zostera japonica on the growth of the native seagrass Zostera marina in their shared transitional boundary. The study measured the leaf growth and new shoot recruitment of 28 individual Zostera marina plants in the presence and absence of Zostera japonica. Leaf growth and shoot recruitment were measured at two week intervals from 10 July 1994 to 24 August 1994. The results of this research show that Zostera japonica inhibited the leaf growth and shoot recruitment of Zostera marina during the latter half of the study. This research is important in that it suggests competitive interaction between the species, and it provides a basis for further investigation into the interaction of these two species.