Linear relationship of acoustically detected migration passage day of year (DOY) by year and by melt-out and freeze-up DOY from 2008–2018.

a) bowhead whale migration DOY in spring; b) bowhead whale migration DOY in fall. DOY over 365 indicates passage date in January 2017; c) bowhead whale migration and spring melt-out DOY; d) bowhead whale migration and fall freeze up DOY; e) beluga whale migration DOY in spring; f) beluga whale migration DOY in fall; g) beluga whale migration and spring melt out DOY; h) beluga whale migration and fall freeze up DOY. Trend, fit (r²), and F-statistics of acoustic migration DOY by year and sea ice thaw/freeze up DOY over time are shown on each plot. Significant statistical relationships (p<0.05) are shown in bold type on the figures.