BIOLOGICAL INVESTIGATIONS 



1. Analyses of Foramlnifera ; The f oraminifera, because they are 

 small, shelled protozoans, had several attributes which made them 

 one of the most profitable animal groups studied. They left 

 easily identifiable shells in the sediment when they died. These 

 shells provided a biological history of the benthos which could 

 be compared to the copper and nickel history of the sediments 



and yielded information on conditions in Safe Harbor dating back 

 to before the plant was built. 



In the collection of any biological field data, it is important 

 to obtain enough specimens to be statistically valid and to be 

 confident of obtaining the most representative species at any 

 particular station. Foramlnifera were easy to collect in large 

 numbers and were readily identified. Foramlnifera experts are 

 not uncommon and foramlnifera identification catalogues have 

 received considerable attention from geologist of oil companies. 



2. Settlement Panels ; The second most useful biological data came 

 from the wooden settlement panels. These collected organisms 

 over known exposure times and on substrates which were uniform 

 in size and material. Monthly collections showed availability 

 of larvae (reproduction and recruitment) , diversity, relative 

 abundance, growth, and mortality of a variety of common fouling 

 organisms. Because of the uniform exposure and substrate, 

 quantification of the data were simplified. 



3. Transects ; Transects proved valuable in assessing general trends 

 in macroinvertebrates . The transects were more useful than the 

 quadrats as larger sections of the benthos were examined. They 

 were oriented toward determining changes in particular organisms 

 rather than attempting to quantify the entire population structure. 



4. Laboratory Bloassays : Acute static bioassays determined the 

 relative toxicity of the effluent and identified the most toxic 

 element. The bioassays were not designed to be overly sophis- 

 ticated yet they yielded the desired information without elaborate 

 procedures . 



5. Quadrat Analyses : Although difficult and time consuming, the 

 quadrats provided useful information on diversity and population 

 structure. Similar conclusions were abailable from the foramlni- 

 fera and settlement panel experiments but quadrats included data 

 on a wider variety Q-f organisms. 



6. Transplants : Transplant experiments were relatively inexpensive 

 in terms of time and materials needed for assessment of the in 

 situ effects on the test animals. Critical examination of the 

 results, however, showed the only fact of major significance 



