9 May 2022

Leucorhoa, leucorhoa!

 One of the features of late spring migration on Hilbre is the passage of Greenland Wheatears (Oeananthe oenanthe leucorhoa) These aren't a separate species but a race of our commoner Northern Wheatears (Oeananthe oenanthe). They're bigger and bulkier and tend to migrate later than Northern Wheatears. They use Hilbre as a stop off point and replenish their fat reserves before continuing their migration across the Atlantic to either Iceland, Arctic Canada or Greenland to breed. 

Because of covid  I'd not been able to get to Hilbre for almost two years but finally with the removal of restrictions I've been managing to get across a bit this year. I was lucky enough to retrap a female Greenland Wheatear on several occasions over the last week since she was ringed.

She was ringed on 27th April and weighed 31.7 g, on 29th she weighed 32.8 g and on the 4th may she weighed 35.7 g! Fat deposits are the birds equivalent of rocket fuel! 

By contrast this beautiful male was ringed yesterday and weighed a whoppping 40.2 g! He'll be on his way very soon.
This bird was aged as a second calendar year male (Euring 5) becuase of the contrast between the browner coverts and dark loral mask. In a full adult these would be the same colour. 

Whinchat are another migratory species that sometimes end up on Hilbre in spring with the occasional one caught and ringed. There was a single male on the morning I arrived and this promptly disappeared but then a pair appeared after the hight tide. 

As well as reacquainting my self with the Wheatears I also got to ring whats probably my first Sedge Warbler since 2019! Great little birds and one I used t o be very familiar with when I first started ringing at Wicken Fen.

Most of the waders are now migrating north to breed but there are still a few hanging around the island including a fine summer plumaged Purple Sandpipier. Not a plumage we get to see very often as most of the Purple Sandpipers don't linger into May.

Likewise with the Dunlin. A flock roosted art the north end and there were a variety of plumages on show - ranging from almost full summer to still in their drabber winter colours.

Maintenance is an ongoing past time on Hilbre. The winter storm take their toll on the infrastructure and our heligoland traps. The SK heligoland had suffered some damage to the cliff top east side entrance baffle so work started to replace this as it'll help funnel birds flying down the bushes on the east side into the entrance of the trap.

All in all it was a fairly good day. A few nice birds ringed to keep the annual totals ticking over and some essential maintenance started!

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