362 OCEANOGRAPHIC INVESTIGATIONS 



Attraction of Marine Animals to Objects Placed on the Sea Floor 



It is known that objects placed on the sea floor attract various forms of marine life. For 

 example, the writers have observed that fish are attracted to mine cases within minutes after 

 plant, and the population becomes more concentrated during the first month of exposure. It 

 was planned to place several mine cases at varying distances from Sealab, inspecting these 

 periodically and recording the types, number, and behavior of the various organisms attracted 

 to these objects. The writers were unable to plant these objects as planned (during Team 1 

 occupancy of Sealab), since the bottom had not been adequately surveyed; hence it was ques- 

 tionable if the mines could be relocated for observational purposes. During Team 2's occupancy 

 of Sealab, the writers surveyed the bottom and inspected several possible sites for this exper- 

 iment. It was decided, however, that it would be impractical to attempt this study as planned, 

 since Sealab had affected the ecology of a much greater area than had been expected. Hence 

 the mine cases would have had to be placed several hundred feet away, requiring at least 30 

 minutes bottom time of two divers to make these observations. 



Study of the Animal Shadow Zone in the Lee of Sealab 



It has been noted that various forms of marine life, fish in particular, are attracted to the 

 upcurrent side of large objects placed on the sea floor. It was planned to study this phenomena 

 during Team 2's occupancy, making population counts on both sides of Sealab, the power hive, 

 PTC, and the benthic lab. The low- current regime which prevailed throughout Team 2's oc- 

 cupancy made this study impractical. 



Study of the Reaction of Bottom Fish to a Low Barrier. 



It has been noted that certain bottom fish will swim around a barrier that happens to be 

 in their path rather than swim over it. This appears to be true even if the barrier is only 

 one to two feet high, but many feet in length. It was planned to construct a small fence outside 

 Sealab and make observations of the reaction of the fish to this barrier through a porthole win- 

 dow. The low light level and visibility conditions which prevailed near the bottom during Team 

 2's occupancy of Sealab made this experiment impractical. 



CONCLUSIONS AND RECOMMENDATIONS 



In this section are presented those conclusions and recommendations regarding ocean- 

 ographic research from Sealab- type habitats which appear valid and useful at this time. Also 

 included are some discussions of subjects which, while not directly concerned with oceanogra- 

 phy, definitely limit the amount and quality of work attainable; these items are discussed from 

 the point of view of providing more diving time per day per oceanographer. It is felt that, as 

 far as doing oceanographic research is concerned, diving time should be at least four hours 

 per day. In Sealab 11 it was difficult to attain even two hours per day, and much of this time 

 was devoted to logistics and housekeeping. We will not discuss in detail the most critical sin- 

 gle "bottleneck" of Sealab II, the entry way and staging area; it is notoriously obvious by this 

 time that these areas need to be several times as large as in Sealab II, that divers need to be 

 able to work all around the entry well, and that the entry ladder needs to be of a type suitable 

 for divers to climb. Several recommendations concerning philosophy and design of Sealab will 

 now be discussed. 



The established and recognized policy of Sealab II was that team members be primarily 

 divers; assignments associated with specialization and/or skills were of secondary importance 

 relative to being a diver. ='= Now that this approach has been tried, it is recommended that the 

 established crew operating policy of the rest of the Navy be utilized in the future, namely, that 



*Project Manager's Note: A number of recommendations on team make-up and Sea Habitat or- 

 ganization have been made by the various aquanauts , this being one rationale. Sealab II was 

 conducted as the first multidiscipline saturated diving experiment, and there were even great 

 differences of opinion between divers concerned with the same ocean-floor problem, i.e., sal- 

 vage divers, as well as differences between Teams 1, 2, and 3. 



