PERCENT RETRAPPED (4-YEAR MEANS)~~ 
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4 6 8 io = 12 4¢ 6 8% 20 22 24 26 
YEARS AFTER ORIGINAL BANDING——#—— 

Figure 11.--A Survival Curve for Common Terns, Based on 
Percent Trapped (l-year means 1936-191) 
after Austin (1942). Solid line represents 
retrap data, broken line potential survival. 
