A big thank you to Christchurch International Airport, who sponsored the helicopter flight along the Waimakariri River from the river mouth to the gorge. This helps complete the picture of the national survey of critically endangered black-billed gulls currently being undertaken.
See if you can spot the black-billed gulls in photos 6-8. It might look like there are plenty of these birds around because they nest in colonies, but this colony of around 300 birds was the only one spotted in the vast lower Waimakariri River.
Not so welcome was the large numbers of predatory southern black-backed gulls nesting all up and down the river (photos 4-5).