Table 1 Results of the Poisson Generalized Linear Model (GLM) testing whether the occurrence of North Atlantic right whales in the regions differed over two time periods (2004–2010; 2011–2014).

From: Long-term passive acoustic recordings track the changing distribution of North Atlantic right whales (Eubalaena glacialis) from 2004 to 2014

Response: # days with NARW presence

Chi-Square

Degrees of Freedom

P-value

timePeriod

21.57

1

3.41e-06***

Region

542.81

5

<2.2e-16***

timePeriod:Region

489.70

5

<2.2e-16***

  1. The number of days in which whale calls were detected is the dependent variable, and the time periods and regions are independent variables, with their interaction effects included in the model. Davis Strait, Iceland and Greenland, Georges Bank, Cape Hatteras, and Bermuda and the Caribbean (regions 1, 2, 6, 9 and 11) are excluded from the model due to insufficient data in some time*region cells. For all other regions, both factors and their interactions were significant. Table 1 shows the overall GLM results between the two time periods (timePeriod) and region (Region). (***) indicates significance of P < 0.001.
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