Salmon return to heart of Vancouver after 50-year absence
Environmental improvements including cleaner water and a fish ladder prompt salmon to spawn
The salmon, scarred and exhausted, swim slowly around each other as they near the end of their final journey.
Hook-jawed males snap at each other as they joust for position alongside female fish, which thrash on their sides in the shallows to clear a spot in the gravel bed in which to deposit their precious eggs, before dying.
It's a poignant scene that has played out in countless wildlife documentaries. But the backdrop to this drama is not some remote Canadian wilderness. These chum salmon are spawning in the heart of metropolitan Vancouver, for only the second time in at least half a century.
A Skytrain rumbles past, carrying commuters oblivious to the life-and-death struggle playing out just metres away in tiny Still Creek. One block to the south is a huge Wal-Mart. One block north is Broadway, Vancouver's main east-west thoroughfare. These salmon have made their way under highways and past rail lines, warehouses and tracts of suburbia to end their lives and beget a new generation next to a hardware store's car park.
River restoration expert Dr Ken Ashley said the return of the chum salmon to Still Creek was a pivotal moment for urban streams, which are often overlooked.
"It makes me very happy. It's taken a lot of hard work to get here," said Ashley, director of the Rivers Institute at the British Columbia Institute of Technology.