Abstract
Transplants were established in February and December 1997 to supplement and provide feedback for a mechanical seagrass transplantation programme. A total of 580, 15 cm diameter plugs of Amphibolis griffithii were transplanted to depths of 5, 6, 8 and 10 m with similar energy conditions, and their survival monitored. There was a significant decline in plug survival over the subsequent 14 months. This appears to correlate with the onset of the winter storms in May 1997; the control plugs (seagrass excavated and replanted in the same location) also declined during this period. There was a seasonal decline in stem density in all plugs, with some recovery in the following spring and summer. The decline of plug survival corresponded to large-scale fluctuations in sediment levels across Success Bank. This suggests that, provided the transplants survive hydrodynamic disturbances resulting in sediment level fluctuations, the light climate (up to 10 m depth) does not prevent the survival and growth of seagrass transplants.