PROTECTION 

 Sea Gull Deterrent 



When the tower was originally in- 

 stalled, sea gulls lined the rails and 

 littered the decks. To rid the installation 

 of these pests, a covey of imitation owls 

 was posted at strategic points around the 

 tower. Initially, the owls were success- 

 ful in scaring the birds away. Later they 

 became accustomed to the owls and re- 

 turned. Periodic broadcasts of tape- 

 recorded gull distress calls were then 

 introduced. The cries of anguish take 

 place every hour. As a result the tower 

 is now nearly free of sea gulls. 



Fouling and Metal Protection 



Corrosion protection below the 

 water level was originally provided by a 

 cathodic system consisting of four bat- 

 teries of zinc anodes charged with low 

 voltage. The voltage balances the elec- 

 trical potential created by the steel 

 framework in salt water. After 5 years, 

 the underwater portion of the tower shows 

 no appreciable damage due to corrosion. 

 A more permanent system consisting of 

 platinum anodes has now been installed 

 to replace the zinc. 



Mounted owl acts as a sea gull deterrent. Another 

 deterrent is 3-minute herring gull distress calls 

 broadcast from speakers mounted on upper deck rail. 



Meters and controls for cathodic protection are 

 mounted in the instrument house. 



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