Fish Distribution 



The tower environment attracts 

 and maintains certain varieties of fish. 



Studies of fish behavior under- 

 neath and adjacent to the structure are 

 facilitated by the remotely monitored and 

 controlled television system attached to 

 the south rail track. The cameras, with 

 their automated pan and tilt mounts, fol- 

 low both horizontal and vertical animal 

 movements. 



A technique and a graphic guide for 

 identification of the fourteen common 

 species of fish viewed on the television 

 monitor have been developed and used 

 successfully. The method utilizes a 

 series of binomial choices based on physi- 

 cal appearance and movement. For ex- 

 ample, a fish is initially classified by 

 body shape, then by fin location or swim 

 pattern, and finally by body markings. 



Television observations of fish 

 over several days at regular time and 

 depth intervals have revealed: 



The vertical layering of various 

 species during the day. 



Changes in vertical distribution 

 patterns at night. 



Avoidance and attraction of vari- 

 ous species by camera lights and 

 TV tilt- train noise. 



Changes in schooling and behavior 

 traits at various times of day. 



Schools of pelagic mackerel are common visitors 

 around the tower during the winter months but are 

 relatively rare at other times of the year. 



^vr'r 



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