Sunday, 15 April 2018

Brackenhurst, Sunday 15 April

Jim, Duncan, Vicki and I made our way to Brack on Sunday for what was planned to be the last ringing session of the 'winter'. Having had a decent session last week, we were wondering what the day would bring. It seems the Yellowhammers are still reliant on the feeding station, perhaps due to the late spring. We were catching them steadily at the feeders all morning, but otherwise, diversity was quite low, except for a few more Reed Buntings to add to the decent winter totals.

Having had some success with the warblers last week, we put two lines of nets in Orwin's, and had a decent first round, but catching quickly dropped off after that. It was interesting to get some chunky Blackcaps, carrying good amounts of fat, with a bias towards female birds.

Other highlights included the first Sparrowhawk since 2012, a young male bird, and overhead were a few Fieldfare. A Tawny Owl was also calling nearby from beyond Orwin's.

Species totals were (new/retrap) 39/38, total 77: Sparrowhawk 1/0, Goldcrest 1/0, Blue Tit 0/1, Great Tit 2/5, Chiffchaff 3/0, Blackcap 6/0, Wren 0/1, Dunnock 1/0, Chaffinch 1/2, Yellowhammer 20/28, Reed Bunting 4/1.

The oldest retrap was a Great Tit from 2014. More than half the Yellowhammers were already ringed. Of the 28 Yellowhammer retraps, the oldest were: 2014 x1, 2015 x3, 2016 x2 and 2017 x4. This perhaps suggests we are now sampling a much more localised population a we approach ‘yammer breeding season, and also underlines importance of supplementary feeding during the ‘hunger gap’. Worryingly, another Yellowhammer was caught with similar symptoms to the Chaffinch papillomavirus disease. Only small numbers of birds have been encountered with such symptoms so far and hopefully it won't become quite so prevalent as it is in the Chaffinches. The bird in question was released unringed, and measures taken to avoid the spread of infection.

Jim and Tom

 Yellowhammer showing symptoms of presumed papillomavirus (T. Shields)

1 comment: