Table S2.

Simulated downwind voyages arriving at the Mariana Islands from distinct origin sites

Origin	January	February	March	April	May	June	July	August	September	October	November	December
Maluku	0%	0%	0%	0%	0%	0%	0%	0%	9% (56–137) [85]	2% (57–91) [74]	0%	0%
West New Guinea	0%	0%	0%	0%	0%	0%	3% (77–181) [114]	3% (56–184) [104]	7% (101–141) [122]	8% (65–178) [99]	0%	0%
Central New Guinea	0%	0%	0%	0%	0%	0%	0%	13% (60–175) [104]	25% (58–198) [104]	2% (63– 116) [90]	0%	0%
East New Guinea	0%	0%	0%	0%	0%	0%	0%	6% (84–192) [119]	6% (106–138) [118]	3% (166–175) [170]	0%	0%
Bismarck Archipelago	0%	0%	0%	0%	0%	0%	1% (90) [90]	4% (137–176) [152]	13% (54–158) [93]	9% (76–191) [79]	0%	0%
Palau	0%	0%	0%	0%	0%	0%	0%	2% (60–64) [62]	2% (48–56) [52]	1% (32) [32]

Month columns refer to start of simulated voyage. Percentage values refer to probability of crossing success. Numbers inside parenthesis provide the range, in days, of crossing duration, and number inside square bracket the average crossing duration, also in days. Simulated trips that resulted in no successful crossings are not shown.