Ecological Archives E096-149-A8

Joseph A. LaManna, Amy B. Hemenway, Vanna Boccadori, and Thomas E. Martin. 2015. Bird species turnover is related to changing predation risk along a vegetation gradient. Ecology 96:16701680. http://dx.doi.org/10.1890/14-1333.1

Appendix H. Conifer removal effects on densities of bird species and combined nest predators.

Table H1. Conifer removal effects on densities of bird species and combined nest predators in western Montana, USA. For each species, the χ² statistic and corresponding p value from likelihood ratio tests, which tested the significance of a treatment-by-time (before/after conifer removal) interaction compared with a null model, are presented. Also presented are the estimated densities in treatment stands before and after conifer removal after correcting for changes in densities on control plots. This difference was then transformed into a percent difference (% Change ±1 SE), and partial η² effect sizes are also presented. Significant effects (p < 0.05) are bolded and marginally significant effects (p < 0.10) are italicized. Bird species are ordered according to effect size of PC axes on density (see Appendix E).

Species

χ²

p value

Density Before

Density After

% Change

% Change SE

Partial η²

Western Wood-pewee

5.40

0.020

0.00

0.10

100.0%

44.1%

0.50

Mountain Bluebird

6.24

0.013

0.00

0.14

100.0%

40.6%

0.29

Northern Flicker

4.21

0.040

0.07

0.17

61.1%

30.7%

0.24

Red-naped Sapsucker

0.31

0.580

0.25

0.19

-22.4%

43.7%

-0.18

Mountain Chickadee

4.16

0.041

0.25

0.59

57.9%

29.4%

0.40

Red-breasted Nuthatch

1.00

0.319

0.17

0.29

41.8%

43.9%

0.23

Ruby-crowned Kinglet

4.53

0.033

0.45

0.03

-93.1%

44.8%

-0.33

Chipping Sparrow

6.60

0.010

0.68

0.08

-88.4%

35.1%

-0.75

Dark-eyed Junco

0.72

0.395

0.66

0.91

27.4%

34.2%

0.28

Yellow-rumped Warbler

0.39

0.531

0.28

0.38

26.2%

44.7%

0.04

Lincoln's Sparrow

4.33

0.037

0.06

0.26

78.7%

39.4%

0.53

Yellow Warbler

5.26

0.022

0.00

0.08

100.0%

35.4%

0.67

Dusky Flycatcher

3.41

0.065

0.45

1.04

56.6%

32.6%

0.62

Warbling Vireo

10.22

0.001

0.53

1.00

46.5%

14.4%

0.72

American Robin

11.62

0.001

0.33

0.65

48.9%

13.5%

0.77

Combined Nest Predators

8.06

0.005

1.16

0.15

-87.5%

30.9%

-0.83


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