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Table 4 Summary of the best models explaining wolf pack density from spatially explicit capture-recapture data collected during sessions 2014 and 2015 (Arezzo province, Italy). a) parameters estimated by the Bayesian approach in SPACECAP; b) parameters estimated by the maximum likelihood approach in secr

From: Estimation of pack density in grey wolf (Canis lupus) by applying spatially explicit capture-recapture models to camera trap data supported by genetic monitoring

a)

Session

Model definition

Parameter

Posterior_Mean

Posterior_SD

95%_Lower_HPD_Level

95%_Upper_HPD_Level

z-score

Bayes p-value

2014

NE_NULL

 

0.714

σ

2871.93

170.52

2565.85

3226.57

0.0404

 

λο

0.9028

0.4192

0.3154

1.7200

0.2870

 

Ψ

0.2880

0.0844

0.1358

0.4552

0.2071

 

Nsuper

31.20

8.14

17

47

−0.0156

 

Density

1.31

0.34

0.71

1.97

  

2015

HN_NULL

 

0.609

σ

2424.42

137.63

2181.91

2715.64

−0.8695

 

λο

0.1220

0.0176

0.0882

0.1573

0.9000

 

Ψ

0.2238

0.0590

0.1142

0.3393

0.2409

 

Nsuper

28.94

6.37

17

41

0.6992

 

Density

1.21

0.27

0.71

1.72

  

b)

Session

Model definition

Parameter

Mean

SE

95%_Lower_HPD_Level

95%_Upper_HPD_Level

2014

NE_NULL

σ

1173.51

152.14

911.16

1511.4

go

0.6879

0.2985

0.13

0.97

Density

1.21

0.4

0.64

2.26

2015

HN_NULL

σ

2428.29

133.35

2180.665

2704.03

go

0.1162

0.0156

0.0898

0.15054

Density

1.15

0.34

0.65

2.04

  1. NE and HN indicate, respectively, the negative exponential and half normal detection function. TP and NULL indicate, respectively, model with or without a behavioural trap effect as covariate. Density is expressed as number of wolf packs/100 km2. In SPACECAP the parameter σ is a “range parameter” of the species, λο is the expected encounter frequency of an individual (i.e., focal animal) whose activity centre is exactly at trap location, Nsuper is the estimated number of individuals (i.e., focal animals) located in the state-space S, Ψ is the ratio between Nsuper and the maximum allowable number of individuals (i.e., focal animals) in S set by the user during data augmentation. Density is obtained dividing Nsuper by the surface of the state-space S. In secr, parameters σ and go are analogous to σ and λο in SPACECAP