Tarāpunga/The black-billed gull

On one hand, you have New Zealand’s most common coastal gull, the red-billed gull. On the other hand, you have this guy, the black-billed gull (Larus bulleri), which is not just New Zealand’s most threatened gull species, but the world’s most threatened. Their numbers are still okay, but the rate of decline is a serious worry: The black-billed gull’s stronghold is Southland, and there its population has declined by 80% in the last thirty years. This bird was photographed at Lake Rotoiti, in Nelson Lakes National Park. Gulls are often thought of as seabirds, but the black-billed gull is more likely to be found around freshwater: rivers, lakes, marshes, pastures. They breed on the gravel beds of braided rivers, which provide them with a clear space to nest on and easy access to a reliable food source. In 2016, a dairy farm in North Canterbury hosted a colony of 300 black-billed gull nests, which fledged 440 chicks. In the Tasman District, black-billed gulls occasionally breed at Farewell Spit and Rototai, but not in large numbers.