Dogs and drones: how scientists are saving Washington’s endangered orcas

Experts are finding new and more humane ways to protect the last 74 southern resident killer whales

Nestled between the US state of Washington and Vancouver Island, the San Juan Islands are a vibrant haven for North American wildlife. Here, all of the world's remaining 74 southern resident sub-species of orcas find sanctuary, surfacing daily from the depths of the Salish Sea.

Out at sea watching the whales is Dr Deborah Giles, an orca scientist, with her colleague, Eba. Eba is a brown and white rescue dog with a remarkable nose. Found as a cold, wet, five-month-old puppy on the streets of Sacramento, she has been detecting whale scat - or faeces - since the age of four.