Table 12.1
Summary of the results of generalized linear mixed models (GLMM) used to evaluate the impact of a railway on breeding and wintering
shorebirds in saltpans of Ria de Aveiro (Portugal)
GLMM
AIC
Model comparison
Interaction terms
Full model
Null model
Dev
df
p
Contrast
Coef
SE
p
Breeding shorebirds
Abundance
Black-winged Stilt
a
2290
2298
13.63
3
<0.010
2006 versus 2008
−0.24
0.25
0.325
2006 versus 2009
0.19
0.25
0.438
2006 versus 2011
−0.73
0.26
<0.05
Kentish plover
a
1887
1930
49.00
3
<0.001
2006 versus 2008
0.64
0.26
<0.05
2006 versus 2009
0.23
0.26
0.386
2006 versus 2011
−1.46
0.30
<0.001
Little tern
a
2040
2058
24.21
3
<0.001
2006 versus 2008
1.34
0.46
<0.01
2006 versus 2009
1.09
0.42
<0.01
2006 versus 2011
−0.63
0.48
0.189
Breeding parameters (Black-winged Stilt)
Nest distribution
b
455
447
7.38
8
0.50
Null model accepted
Nest success
a
154
154
6.45
3
0.09
Null model accepted
Fledging success
a
90
86
1.87
3
0.60
Null model accepted
Wintering shorebirds
Abundance
a
1293
1299
12.49
3
<0.01
2006 versus 2008
−2.91
1.59
0.067
2006 versus 2009
1.52
1.48
0.304
2006 versus 2011
−3.01
1.52
<0.05
(continued)
206
T. Múrias et al.