19. Effluent reduced numbers of barnacles, bryozoans, and 

 sabellids settling on settlement panels in Safe Harbor. 



20. Asoidia nigra and most oysters were excluded from the 

 Safe Harbor canal during most of the study period. 



A, nigra returned when copper concentrations decreased. 



21. Quadrats showed a gradual biotic depletion. Annelid 

 worms, blue-green algae, and bryozoans comprised the 

 benthic flora and fauna in Safe Harbor during most of 

 the study period. 



22. Stone crabs and lobsters decreased in transect areas. 

 Lobsters were attracted to the desalination plant sea 

 wall during cooler winter months. Fish were more abun- 

 dant near the discharge than elsewhere in the study 

 area. Some of these were injured by copper toxicity. 



23. Transects showed a decrease in echinoid populations on 

 Thatassia flats to the west of the Safe Harbor turning 

 basin. High copper levels in sediments from this area 

 implicated the effluent in the echinoid mortality. 



24. ThaZassia grass beds surrounding the entrance to Safe 

 Harbor did not change their distribution appreciably 

 between 1968 and 19 71. 



25. Copper uptake and toxicity increased with increasing 

 illumination in phytoplankton samples and in the 

 ascidian, Asoidia nigra. 



10 



