Audio-visual artist Kathy Hinde is entranced by "an apparition" of knot.
Audio-visual artist Kathy Hinde is inspired by the spectacle of migrating barnacle geese.
Audio-visual artist Kathy Hinde is captivated by a flock of pink-footed geese.
Audio-visual artist Kathy Hinde recalls being surrounded by dancing common cranes.
Professor Andy Radford recalls first hearing curlews as a child on the Yorkshire moors.
Professor Andy Radford describes a noisy encounter among green woodhoopoes.
Professor Andy Radford describes the role of the sentry amongst pied babblers.
Professor Andy Radford reveals the importance of alarm calls to the superb fairy-wren.
Professor Andy Radford is captivated by the vocal repertoire of the robin.
Wildlife cameraman Doug Allan recalls hearing an emperor penguin chick for the first time.