Table 2. Total number of occupied fields, total number of occupied 50-m sampling stations, and abundance of birds within occupied 50-m sampling stations by male Savannah Sparrows (SAVS) and male Bobolinks (BOBO) on point counts conducted in the Champlain Valley, May 21 to July 2, 2002. The columns for Mean and SD refer to the number of birds per count within 50 m of the sampling station on counts that contained at least one Savannah Sparrow or Bobolink. Notice that the density of SAVS and BOBO in occupied sites increases on each successive visit.
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| |
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|
|
Number occupied |
|
Bird abundance |
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|
|
|
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|
|
|
|
|
|
Visit |
Field |
50 m |
|
50 m |
Mean |
SD |
| |
|
SAVS |
1 |
62 |
22 |
|
26 |
1.18 |
0.50 |
|
|
2 |
65 |
33 |
|
45 |
1.36 |
0.60 |
|
|
3 |
64 |
28 |
|
45 |
1.61 |
0.92 |
|
BOBO |
1 |
77 |
32 |
|
69 |
2.16 |
1.23 |
|
|
2 |
63 |
31 |
|
81 |
2.61 |
1.82 |
|
|
3 |
48 |
26 |
|
74 |
2.85 |
2.58 |
|
| |
|