Different Day, Different Birds

Monday saw a catch of 33 birds up at Oakenclough. Domestic commitments meant I couldn't make it on the next suitable morning, Wednesday, even though I was raring to go. Andy went alone and caught 60 birds, including another 15 Redwings and 8 more Lesser Redpolls. 

With so many millions of birds on a migratory push through the UK and Europe at this time of year there is a guarantee that each visit brings new birds to our nets. 

So with yet another excellent forecast we arranged to meet up again at Oakenclough on Thursday. We were joined today by Bryan H. At 0700 there was a slight breeze from the east with nil cloud and a temperature hovering around 2°C. 

The lack of cloud meant that migration might at the least prove hard to pick up or even non-existent if birds had found their way through the clear starry night. We needn't have worried too much as although small passerines were scarce there was a huge rush of northern thrushes and we kept busy throughout. 

By 11 am we had counted a minimum of 900 Fieldfare and 400 Redwing passing overhead. The thrushes were arriving from east and south-easterly directions and not from the north as we perhaps thought they might. This is suggestive of east coast arrivals with subsequent travel over the Pennines on west and south-westerly headings. 

Although Fieldfares easily outnumbered Redwings in the overall count, we caught proportionally more Redwings. This is due to the larger size of the Fieldfare and its ability to escape from a mist net, but also to its overall wariness when man is around. We also think that Fieldfares have superior eyesight to Redwings and are less likely to find themselves in a mist net, even in the half light of morning. In many countries of Europe, Fieldfares are hunted mercilessly, as are Redwings.  

Totals today: Redwings made up 50% of the catch - 42 birds of 10 species: 22 Redwing, 3 Fieldfare, 1 Blackbird, 5 Goldfinch, 3 Great Tit, 2 Chaffinch, 2 Lesser Redpoll, 2 Coal Tit, 1 Blue Tit, 1 Wren, 

Field Sheet (Part)

The below Fieldfare is a first year male - amount of black in crown feathers, contrast in primary and secondary coverts. Tail feather shape. 

Fieldfare

Fieldfare 

Fieldfare

The Redwing below is a classic first year. Note the “pointy” tail feathers and the whitish notches on the tertial feathers. 

Redwing 

First year tail - Redwing 

Adult tail - Redwing 

Wing Tracts 

Unlike the last two visits here, Lesser Redpolls proved hard to come by. Their visible migration was zero, likewise Chaffinches, even though we caught two of each species. 

Lesser Redpoll 

Out of interest, and to remind ourselves that the Common Redpoll and the Lesser Redpoll are now lumped together (again). 

The taxonomy of redpolls remains unsettled, part of an ongoing debate that recognises several different but very closely related forms of redpolls, considered as anything from one to five species. After a number of attempts and changes of mind by “experts”, the UK/European Lesser Redpoll is now assigned as a geographic sub-species of Common Redpoll by recent genome wide analyses that found differences in gene expression but no genetic divergence. This gives credence to the idea that the essentially plumage forms (like our own rather brown Lesser Redpoll) originated quite recently within a single interbreeding lineage and do not represent species boundaries. 

Well, what do you know? The forecast is good again for Friday. Looks like we are in for more different birds.

Linking this post to Eileen's Nature Blogspot.