SMITH ET AL . TRANSPLANTED EELGRASS FOR BAY SCALLOPS 

 NATURAL SCALLOPS 



SURVEY I 



Block 1 



94.7% 



Natural Abundance 



^S- 



Unvegelaled Sand Lp/^ 



^^Q b[T] 



LPA 



hpaQ bQ 



Dredge Island 



Block 



 of Scallops 



125 

 50 

 32 



Figure 4.— Distribution of natural scallops as number per experimental unit survey (56.25 m^) on 30 March 1986 (survey I). Treatment 

 types: NI = Natural Interior: NE = Natural Edge, HPA = High Perimeter to Area, LPA = Low Perimeter to Area. B. = Bare. 



Due to enhanced seabird predation, restoring eel- 

 grass beds adjacent to these islands will likely not 

 provide a suitable area for bay scallop stocking until 

 the bed matures and coalesces. These results may 

 not be widely applicable because our study focused 

 on a single eelgrass-dredge island system over one 

 scallop settlement season. However, it is apparent 

 that the location and manner of dredge material 

 disposal should be examined closely. Although shore- 

 bird and seabird habitat was certainly enhanced by 

 the creation of the dredge material island, there may 

 be local environmental and economic impacts on the 

 scallop population and its fishery, as well as other 

 existing, soft bottom communities, even without 

 direct destruction of the adjoining seagrass bed itself 

 as evidenced by the gradient of scallop abundance 

 away from the island. 



There are two major conclusions to be drawn from 

 this study. First, if natural eelgrass meadows are 

 destroyed and transplants are used as replacements 

 for the lost habitat, it is essential to recognize that 

 the transplants will not immediately function as the 

 natural bed it replaced. The delay or lack of habitat 

 replacement could permanently reduce the produc- 

 tion of economically valuable fauna in the area if 

 proper measures are not taken to insure that any 

 removed or destroyed eelgrass is properly balanced 

 with a functionally equivalent habitat replacement. 

 Second, this study has shown that natural eelgrass 

 beds at this site provided a substantially more suit- 

 able habitat for scallops than the transplanted treat- 

 ments, within the first 5-6 months after planting. 



Stocking of recently transplanted eelgrass beds with 

 scallops as a means of restoring or enhancing that 

 fishery cannot be supported by these data. 



ACKNOWLEDGMENTS 



We would like to thank David Colby, Ford Cross, 

 David Meyer, Jud Kenworthy, Gordon Thayer, and 

 two anonymous reviewers for their helpful review 

 comments. Carolyn Currin, Deborah Shulman, and 

 Vicky Thayer assisted with field collections, while 

 Herb Gordy prepared the graphics and Jean Fulford 

 typed the manuscript and revisions. 



LITERATURE CITED 



FONSECA, M. S., W. J. Kenworthy, and G. W. Thayer. 



1988. Restoration and management of seagrass systems, a 

 review. In D. D. Hook et al. (editors). The ecology and 

 management of wetlands. Vol. II: Management, use and 

 value of wetlands, p. 353-368. Timber Press, Portland, 

 OR. 

 Fonseca, M. S., W. J. Kenworthy, G. W. Thayer, D. Y. 

 Heller, and K. M. Cheap. 

 1985. Transplanting of the seagrasses, Zostera marina and 

 Halodule wrightii, for sediment stabilization and habitat 

 development on the east coast of the United States. Army 

 Engineers Waterways Experiment Station, Vicksburg, MS, 

 Tech. Rep. EL-85-9, 49 p. 

 Fonseca, M. S., G. W. Thayer, and W. J. Kenworthy. 



1987. The use of ecological data in the implementation and 

 management of seagrass restorations. In M. Durako. R. C. 

 Phillips, and R. R. Lewis (editors). Proceedings of the 36th 

 Annual Conference of the American Institute of Biological 

 Sciences, p. 175-187. Fla. Mar. Res. Publ. No. 42. 



195 



