Breeding biology of Slender-billed Gull (Larus genei Breme 1839) in West Azerbaijan province, Iran

From April 2014 to March 2015, we investigated Slender-billed Gull breeding biology in multiple temporal islands located in the Shahid Kazemi dam, Bukan, West Azerbaijan province, Iran. During the study period, we monitored a single breeding colony of the Nazargah Island (0.026 sq km) of Shahid Kazemi dam. The breeding colony started nesting and laying in early April, and the first chicks were hatched on 18 May. On the same Island, Common black-headed Gulls also starts nesting much earlier on 21 March, and the first chicks hatch on 30 April. Armenian Gull and Common black-headed Gull also breed simultaneously. More than 400 breeding nests of Slender-billed Gull as well as 200 nests for black-headed Gull and 300 nests for Armenian Gull were recorded. Of about 400 breeding nests of Slender-billed Gull, 123 nests were numbered by flags, and measurements were carried out from nesting to fledging.