Heuglin's Gull (L. heuglini / antelius)
Heuglini adult, January 12-16 2005, Oman: Barka.
Picture by Osao & Michiaki Ujihara: http://www23.tok2.com/home/jgull/OmanGulls/
You can also mail: ujihara"add"mpd.biglobe.ne.jp
In the Arabian Gulf, four species of large gulls can be found commonly. Heuglini, and fuscus are breeding species from the northern tundra. Cachinnans and barabensis are steppe breeders. The breeding location may give criteria for identification of single individuals. Breeding on either southern steppe or northern tundra has some major consequences:
a: the breeding season starts much earlier on the steppe, hence can be finished much earlier.
b: northern breedres must migrate over much longer distances and this has consequences for their moult strategy and timing.
c: steppe breeders spend much more time under tropical climate conditions, while feathers of the tundra breeders are less likely to be exposed to such conditions, and this may have effects on bleaching and wear of e.g. primaries.
The image below shows a preening adult heuglini.
- Upper parts dark grey; much darker than in cachinnans and barabensis; but slightly paler than fuscus.
- Late moult timing of the primaries. In this individual, all old outer primary have been shed, and P8 is full grown. P9 - P10 still growing.
- Visible inner primaries and the primary tips look brand new, recently moulted.
The mirror on P10 is obvious, covering both webs. P9 doesn't show a mirror. Heuglini showing a "merged tip" on P10 seem to be very rare. Merged: the mirror completely merges with the very white tip, so there is no sub-terminal black band. Such a pattern is rare in heuglini.