It depends on which region you plan to travel to.
Antarctica
From the end of October to the beginning of December, the continent is completely covered with snow and this is the most active time for penguins - they trample paths to the water, build nests and lay eggs.
From December to February, the snow recedes, exposing the rocky headlands, and the penguins hatch their first chicks. At this time, the probability of sunny days is higher and the Drake Strait is calmer.
From mid-February to mid-March, whales return to feed, seals come ashore more often, and penguins begin to molt. Antarctica is preparing for long months of darkness.
The Arctic
June – mid-July is the best time to see bears and walruses on ice and snow, because the sun is not particularly active yet. During these months, migratory birds return.
From mid-July to mid-August, there is less ice in the north and many places will open up to you from a completely new side.
From mid-August to September, we recommend visiting the most inaccessible regions of the Arctic, when there is very little ice.