The Blue Planet: Open Ocean

SYNOPSIS

Predators and prey in the open oceans come under the scrutiny of David Attenborough. Marlin track down a shoal of sardines as a sei whale scoops up the leftovers, dolphins herd mackerel and attract the attention of a glamorous sailfish with the resonance of their sonar, and giant sunfish queue up to allow other species, including seagulls, to feed on their parasites.