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Assessing Breeding Populations of Ducks by Ground Counts

Table 14


Table 14. Analysis of variation of dabbler counts taken at three different time intervals, 0800, 1300, and 1800 hours, on 3 days. Data from Table 13
Source of variation Degrees of freedom Sum of squares Mean square F Value
Mallard
     Total 8 2485    
     Time 2 1064 532  
     Error 6 1421 236.8 2.25*
Pintail
     Total 8 744    
     Time 2 408 204  
     Error 6 336 56.0 3.64*
Widgeon
     Total 8 703    
     Time 2 412 206  
     Error 6 291 48.5 4.24*
Shoveler
     Total 8 290    
     Time 2 241 20.5  
     Error 6 49 8.2 14.75^
Gadwall
     Total 8 180    
     Time 2 144 72  
     Error 6 36 6.0 12.00^
Blue-winged teal
     Total 8 1080    
     Time 2 548 274  
     Error 6 532 88.7 3.09*
For 2 and 6 d.f. F05 = 5.14, F01 = 10.92.
*The null hypothesis that no significant difference exists between time means of different time periods is accepted at .05 level.
^The null hypothesis that no significant difference exists between time means of different time periods is rejected at .01 level.

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