29 days had actually landed long before 

 their recovery. The small loss of drags 

 from bottles out more than 119 days (11.8 

 percent — table 1) can be explained in part 

 by the fact that many of these bottles were 

 recovered at unfrequented places aind may 

 have landed many days before they were 

 found. Duck hunters returned a number of 

 these bottles in the fall from marsh areas. 

 Even though the time out for the bottles 

 was around 4 months, total travel from 

 release point was less than 10 miles. 



Remarks made by persons returning cards 

 from bottles with lost drags indicate that 

 the second weakness of the unit is in the 

 attachment of the suspension wire to the 

 drag. The weight of the drag and the stress 

 imposed during the bottle's journey even- 

 tually cut through the wire. Because 

 bottles in this study moved relatively short 

 distances, the percentage of drags lost was 

 small. In an experiment where bottles might 



be expected to be out for an average of 

 over 30 days, the weakness in the suspen- 

 sion of the drag should be remedied. 



The question often arises whether or 

 not a reward should be paid for return of 

 Ccirds. A reward might increase the prob- 

 ability of the return of a reply card that 

 has been found, ajid might encourage active 

 searches for bottles. On the other hand, 

 in projects where a large number of bottles 

 are released the cost of rewards becomes 

 prohibitive. Although the data (table 2) 

 are far from conclusive, it appears that 

 where rewards have been offered, the re- 

 turns have not been consistently (12 to 57 

 percent recovery, average 29.0) greater 

 than in experiments where rewards were not 

 offered (3 to 67 percent, average 28.6). 

 This may not, however, be an entirely fair 

 comparison. Poor returns are to be expected 

 in some experiments and those on which 

 rewards were offered may have been this type. 



Table 2. --Comparison of numbers of "bottles' released and percentage 

 return for each of several areas 



1/ Reported by Sclunidt 1913; not seen by me 

 2/ Type of drift unit not specified 

 3/ Exact amount of reward not stated 



