Ecological Archives A018-040-A7

Arnaud Ghilain and Marc Bélisle. 2008. Breeding success of Tree Swallows along a gradient of agricultural intensification. Ecological Applications 18:1140–1154.

Appendix G. Parameters of the most parsimonious regression models fitted on breeding attempts for which >1 egg hatched or >1 hatchling fledged.

TABLE G1. Parameters of the most parsimonious model inferring within-clutch hatching probability of Tree Swallows (arcsine-transformed) along a gradient of agricultural intensification in southern Québec, 2004–2006. Estimates pertain to a linear mixed model with farm ID as random factor and relative amount of water and extensive culture cover measured within 20 km of the nestbox (n = 715). See Table 1 for variable definition and justification.

Parameter

Estimate

SE

CI (95%)

Intercept

1.703

0.224

1.263

>  β >

2.144

Year 2

-0.032

0.037

-0.104

>  β >

0.039

Year 3

-0.098

0.033

-0.164

>  β >

-0.033

Clutch initiation date

-0.003

0.002

-0.007

>  β >

0.000

Temperature

0.000

0.006

-0.012

>  β >

0.012

Precipitation

0.007

0.005

-0.003

>  β >

0.018

Water

0.025

0.006

0.013

>  β >

0.037

Extensive culture

0.002

0.005

-0.007

>  β >

0.011

Manure tanks

-0.224

0.069

-0.360

>  β >

-0.088

Cattle

-0.001

0.005

-0.012

>  β >

0.010

Extensive culture × manure tanks

0.009

0.003

0.003

>  β >

0.014

Extensive culture × cattle

0.000

0.000

-0.000

>  β >

0.000

 

TABLE G2. Parameters of the most parsimonious model inferring the within-brood number of Tree Swallow fledglings along a gradient of agricultural intensification in southern Québec, 2004–2006. Estimates pertain to a linear mixed model with farm ID as random factor and relative amount of water and extensive culture cover measured within 5 km of the nestbox (n = 597). See Table 1 for variable definition and justification.

Parameter

Estimate

SE

CI (95%)

Intercept

9.109

0.981

7.182

>  β >

11.035

Year 2

-0.047

0.142

-0.326

>  β >

0.232

Year 3

-0.277

0.147

-0.566

>  β >

0.012

Clutch initiation date

-0.043

0.006

-0.056

>  β >

-0.031

Water

0.001

0.044

-0.085

>  β >

0.086

Extensive culture

0.061

0.017

0.028

>  β >

0.094

Manure tanks

0.422

0.222

-0.015

>  β >

0.859

Cattle

-0.006

0.018

-0.041

>  β >

0.029

Extensive culture × manure tanks

-0.019

0.008

-0.035

>  β >

-0.004

Extensive culture × cattle

-0.000

0.001

-0.001

>  β >

0.001

 

TABLE G3: Parameters of the most parsimonious model inferring fledging probability of Tree Swallows (arcsine-transformed) along a gradient of agricultural intensification in southern Québec, 2004–2006. Estimates pertain to a linear mixed model with farm ID as random factor and relative amount of water and extensive culture cover measured within 5 km of the nestbox (n = 597). See Table 1 for variable definition and justification.

Parameter

Estimate

SE

CI (95%)

Intercept

1.599

0.264

1.079

>  β >

2.118

Year 2

-0.003

0.034

-0.069

>  β >

0.063

Year 3

-0.000

0.035

-0.068

>  β >

0.069

Clutch initiation date

-0.002

0.002

-0.005

>  β >

0.001

Chicks hatched

-0.052

0.012

-0.075

>  β >

-0.030

Water

0.005

0.010

-0.014

>  β >

0.024

Extensive culture

0.012

0.004

0.005

>  β >

0.019

Manure tanks

0.092

0.050

-0.006

>  β >

0.189

Cattle

0.002

0.004

-0.005

>  β >

0.010

Extensive culture × manure tanks

-0.004

0.002

-0.008

>  β >

-0.001

Extensive culture × cattle

-0.000

0.000

-0.000

>  β >

0.000


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