Table 1.

Average species richness per trawl (alpha diversity) in the first and last year of sampling predicted from a GAM with Year and Latitude as smooth predictors, and swept area as a logarithmic predictor (%DV = % Deviance explained)

Region	First year of data	Richness first year [lower, upper 95% CI]	Last year of data	Richness last year [lower, upper 95% CI]	% increase [lower, upper 95% CI]	No. of trawls	% DV
Norwegian & Barents Sea	1994	8.0 [7.8, 8.1]	2020	13.4 [13.1, 13.6]	66 [61, 75]	16,283	16
North Sea	1998	11.2 [10.6, 11.8]	2020	16.4 [15.6, 17.2]	46 [32, 6]	2,338	42
Svalbard	1996	6.9 [6.3, 7.5]	2020	12.8 [12.2, 13.5]	87 [63, 115]	2,065	12