PLANET EARTH Seasonal Forests

The cicadas here, will not be heard again for another seventeen years. Having fed the predators, the cicadas leave one final gift for the seasonal forest itself. The nutrients in a generation of cicadas are returned to the soil, all at once and the trees enjoy a marked spurt in growth. This may be the single largest dose of fertilizer in the natural world.



In the great broad leaf seasonal forests of Eastern Europe, the days are beginning to shorten, and a primeval sound heralds the onset of autumn. Male red deer are starting their rut. The air is heavy with the scent of females. The rules are simple. Winner takes all. Across the northern hemisphere the deciduous seasonal forests are changing. Leaves that have provided food and shelter since the spring, are now shed.



In the broad leaf seasonal forests of Russia, winter is particularly severe but there will always be some who benefit from hardship. Black vultures scavenge from the carcass of a seeker deer that has died of cold or starvation. These endangered birds are visitors. They've come down from the north to escape the even colder conditions in Siberia.



An Amur leopard. The rarest cat on Earth. Winter is a difficult time for this hunter. There are no leaves for cover and no young prey animals. This female has the added pressure, of having to provide for her one year old cub. It'll be another twelve months, before he'll be able to fend for himself. The bickering vultures have abandoned the carcass. It's a valuable discovery for the leopards. But the cub doesn't share it's mother's sense of urgency.