Adults have black legs from July to February, then become brown on March, chestnut-red on April to May, then brown on June, then black on July.
1-year-old, after completion of moult of flight feathers, have chestnut orange legs on January to July, then brown on August and black on September, to February.
Juveniles, once fledged, have pink legs on January to February, then pinkish orange on March, then orange On April to August, then brown on September, then black on October to November, then brown on December.
Remember hybrid Red-billed X Black-billed gulls are very rare.
andrewcrossland wrote:Hi team, like Lloyd Ive found red-bills nesting within Black-billed Gull colonies at places like the Ashburton Rivermouthy. Nests are indeed very different and I've looked for mixed pairs, but not seen any.
Are people fully aware that adult Back-bills ofcourse have that period post-breeding when legs turn red and bills can change from black to orange?
BBG 2.jpg
The bands on this bird identify it as at least 10 years old when it was photographed.
BBG 1.jpg
