Sunday 22 April 2018

Pomarine Skuas

Dungeness - warm, dry, sunny, SW2 - 0830-1000hrs - A seawatch in the company of MH and CP this morning produced my first two Pomarine Skuas of spring, albeit distant views, in contrast to several Arctic Skuas (both light and dark phase) that came much closer in their pursuit of Sandwich Terns. Plenty of flocks of Common Scoter, Gannets, Whimbrels, a few Red-throated Divers, seven Little Gulls, a Little Tern, and a mixed flock of Brents and Whimbrels kept the interest going. Once again at least 20 Harbour Porpoises were noted just offshore.
  On the land a Wryneck seen earlier at Long Pits failed to reappear until the afternoon although plenty of warblers were in song, particularly Lesser Whitethroats and a Garden Warbler. Our first two Small Copper butterflies were also noted.
Lade  - Nothing new here from yesterday apart from more Whimbrels over calling and a Mediterranean Gull.




Pom Predictor
So its that time of year again when local birders turn their thoughts towards the spring passage of Pomarine Skuas. A question I am often asked by visitors is, "what is the best time to visit Dungeness to see `em"? There is, of course, no definitive answer to that question as this enigmatic seabird is prone to the vagaries of migration with all its twists and turns.
  Some years only small numbers are recorded passing Channel headlands, probably due to weather systems out in the Atlantic sending them up the western seaboard of the British Isles. However, while a specific date may be impossible to predict recent history has shown that the last week in April and first week in May to be the most reliable period. Occasionally it can be earlier or later by a few days, but almost always straddling the two months and sometimes trickling on until the end of May.
  Generally speaking early morning is best with a wind from a southerly vector and cloud cover, but often if there is a passage pulsing through Poms can turn up throughout the day in ones and twos and even in small flocks. They rarely interrupt their travels to chase terns for fish, just power steadily up-Channel at varying distances from shore, but sometimes inside the Dungeness cardinal buoy. Watchpoints such as Portland, Selsey Bill and Splash Point often get birds before us at Dunge, so it`s worthwhile checking social media for a heads up on what`s happening down-Channel, and the Dungeness Bird Observatory and local Twitter feeds.
  About the size of a Herring Gull, Pomarine Skuas at first glance appear all dark brown, but on closer inspection sport a pale belly, white wing flashes and a broad yellowish neck collar giving a capped appearance. Variable length, spoon-shaped central tail feather complete a distinctive ensemble affording a unique `heavy, rear end` jizz which separates them from the other two regular species (Great and Arctic) noted off Dungeness.
  Having spent the winter months at sea off the west coast of Africa Pomarine Skuas undertake a long migration northwards to breed on the Arctic tundra where they switch from a seafood diet to one of mainly lemmings and fledgling birds. Along with other members of the skua tribe they are fearsome in defence of their nest and young and will dive bomb and strike intruders, including humans.
  Last year the first Poms appeared on 23rd April, all 23 of them, with a peak of 129 on 30th and the final three on 14th May. In 2016 the first two were on 21st April with a peak of 121 on 6th May and the last one on 22nd May (stats from the Dungeness Bird Observatory website).
  And today the first spring Poms of 2018 passed Dungeness, opening another chapter on the fortunes of this enigmatic, migrant seabird.
  

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