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Table 2 Model results for home range area and centroid pairwise distance

From: Modeling the spatial and temporal dynamics of foraging movements of humpback whales (Megaptera novaeangliae) in the Western Antarctic Peninsula

Model Fixed effects Random effect Random slope Response SE AIC ΔAIC χ 2 DF p
Home range area (km 2 ) Month PTT Month|PTT −215.7 36.8 1092 2 7.68 1 0.006
Month PTT Month|PTT −214.9 38.3 1091 1 11.28 2 0.004
+ DTM    2.7 1.4      
DoY PTT DoY|PTT −5.8 1.3 1094 4 2.27 1 0.132
DoY PTT   −6.5 1.2      
+ DTM   DoY|PTT 3.4 1.3 1090 0 8.08 2 0.018
Centroid pairwise distance (km) Month PTT Month|PTT −21.3 4.7 719 2 5.39 1 0.020
Month PTT   −21.454 5.451      
+ DTM   Month|PTT 0.285 0.145 717 0 9.72 2 0.008
DoY PTT DoY|PTT −0.6 0.1352 722 5 5.00 1 0.025
  1. P-value and χ2 values were obtained by analysis of variance tests of each of the full models against a null model. Null models had Distance To Mainland (DTM) as the only fixed effect, to determine if month or Day of Year (DoY) was a significant predictor variable. DoY + DTM centroid pairwise distance model failed to converge and has been omitted. The Platform Transmitting Terminal (PTT) is unique to each whale, and was used as a random effect with by-whale random slope to capture the variation in movements between individual whales. Response is the unit change in the dependent variable (home range area in km2 or centroid pairwise distance in km) per unit increase in the fixed effect variable(s). For example, for each unit increase in month, the home range area decreased by 215.7 km2 with a standard error of ±36.8 km2. The selected model is bolded. The most parsimonious model within two Akaike information criterion (AIC) units of the lowest AIC was selected. SE = Standard Error; DF = Degrees of Freedom; p = p-value.