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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