An in-depth look at the wildlife and natural elements that are abundant during the springtime in Scotland. A female mountain hare tests the virility of male contenders by letting them chase her over the mountains. Spring is also the season when emperor moths emerge from their silk cocoons. The males immediately start trying to find a mate, picking up the females' scent. Back in Shetland, spring plankton blooms have drawn in humpback whales, overlooked by millions ofseabirds, including 25,000 puffins.

It's autumn in Scotland and the clock is ticking. As daylight diminishes and the weather cools, food resources dwindle. Animals must either migrate now or prepare to face the winter head on. Autumn sees the first sprinkling of snow on Scotland's highest peaks. Inland moorlands turn from pink to brown as heather flowers fade.