When I arrive at Bedfont Lakes promptly after sunrise every Sunday morning one of the first birds I hear are Goldfinches. These are one of my favourite birds and regular visitors to my garden, my day is not complete without hearing their delightful melodic twittering! At this time of year you may also spot some courtship behaviour in which the males drop their wings and sway from side to side whilst singing – it’s enchanting! But I always think it kind of looks like they are wiggling their bums 😉 the only video I could find of this behaviour was of a caged bird – perhaps I will make my own! Still, you get the idea.
Anyway, I always hear them but we had yet to ring any this year until a couple of weeks a go one of the ringers decided to try a net in a new place and after a few Greenfinches and a gorgeous female Blackcap we caught a Goldfinch. Knowing my love for these guys I was given the honour of ringing this lovely bird which I was very excited about 🙂
These guys are notoriously difficult to sex. According to Svensson (the ringers bible -‘Identification Guide to European Passerines by Lars Svensson’) there are several things to look at; generally the males have a brighter red mask that extends behind the eye, they have a longer wing length, black as opposed to grey nasal hairs (the hairs just before the beak starts), and black/brown as opposed to brown lesser coverts. However these differences can be tiny and some times one characteristic will contradict another e.g. extensive red mask but short (below 78mm) wing. In this bird the red mask extends slightly behind the eye but after measuring the wing length at 78mm and looking closely at the other features (lesser coverts, nasal hairs) my trainer provisionally sexed it as female. Here is a fantastic photographic study showing all the details to look for and just how much variation there is. Hopefully I will be seeing more of these guys so I can make some of my own comparisons and get to grips with these differences!
Also, here is the female Blackcap….. How beautiful and sleek is she?
We also got a tad over excited about this dozy bee fly that spent a long time sitting on one of the ringers shoulder whilst she was going about ringing birds etc. We named him Brian – naturally 😉