BBC Earth: Earthflight

The bird's eye camera mainly shows North American species migrating, like geese from Mexico to Canada, whose routes are the basis for the program's itinerary. Also shown are seagulls leaving San Francisco's docks to eat specialized flies at a poisonous lake, eagles going for part of the grizzly bears' salmon catch, buzzards hunting in groups, parasite-pickers on buffaloes and waterfowl simpling joining in when dolphins drive fish onto the shore.

Africa and its waters are the scene of major migrations. Seagulls are among the birds who oversee and profit from the arrival of seals and other species on breeding grounds, as in the Cape province. Storks are among the European birds who find warmer refuge in winter. Vultures and many other species find most food along the great savanna trek of wildebeest and other mammals, hunted by the great cats, hyenas, crocodiles. Flamingos are an example of internal African migratory birds.

Every spring, various migratory bird species return to their breeding grounds all over Europe, as far as the wild geese in Scandinavia and northern Siberia or much closer to the Mediterranean. Even at the shortest passages, the Gibraltar Strait and the Marmara Sea, gliding many miles without soil is perilous, but so are predators all along each route, like the peregrine falcon. Some (stork) nests are family heritages for many generations. Human landscape changes, such as urbanization, significantly change conditions. Navigation is by astronomy, earth magnetism and landmarks.

In South America, bird species are adapted to the very different biotopes, from Terra del Fuego and Patagonia to Panama. The condor, a giant vulture, is king of the Andes skies. Parrots abound all over Amazonia. Gannets are prominent among aquatic birds. Some migrate all the way to North America, even Canada.

Bird life in Asia and Australia is as colorful as the human cultures, which tend to close in on their habitats. In Indian nature reserves, some vultures still specialize in air-tailing tigers until they make a kill. Impressive migrations include cranes passing the Himalayas. Australia has fascinating cockatoos.

The making of the previous five episodes. To film 100 bird species worldwide, many in flight, from their own, airy perspective, lots of equipment was used, including light aircraft and miniature cameras, even life-like bird dummies. The key factor however were birds hatched and trained with endless patience. Even then, filming them proved nerve-wracking and sometimes perilous.