Sunday, 27 October 2013

27/10/13 - Calm before the storm

I have been a bit preoccupied in one way or another over the last couple of weeks and hence the lack of posts. However, I haven't been totally idle but most of my ringing has been focused on the Goldfinches in the garden; more of that later. Other birding has been very limited and has been largely confined to birds seen in the course of doing other things. You can take me out of good habitat but you can't take the habit out of me, I will watch birds anywhere I can.

Anyway, yesterday I went to Martin Mere for a change of scenery and while I didn't see anything unexpected it didn't disappoint. Ruff weaved their way through loafing Teal, Wigeon, Pintail, Shelduck and Mallard. A Marsh Harrier put in regular appearances as it quartered the area. Whooper Swans may have had a good breeding season given the number of juveniles in the family parties seen. Last but not least there were the Pink-feet, lots and lots of Pink-feet. There is something magical about large flocks of birds especially when they number in the thousands.

Ruff 26/10/13

Ruff 26/10/13

A record shot of Marsh Harrier 26/10/13

Pink-footed Geese

lots of Pink-footed Geese
This morning the change in the hour caught me out and I was up earlier than planned. The weather equally caught me out as there was no rain and very little wind in the shelter of the garden. I decided to take advantage of these unexpected conditions and put the usual 20ft net up. A couple of hours later I had caught 20 birds including 13 new Goldfinches. This brings the total number of Goldfinches ringed in the garden this autumn to 234.

While this is a good number it is the plumage variations of the sexes and ages that really interests me.  The more I look the more problematic this species seems to be especially in terms of sexing. Ageing is relatively easy at this time of year but gets more difficult towards the spring. I now make a point of taking photographs of many of the birds I catch including the face, back of head, wing coverts and tail. What this will lead to I am not sure yet but I confidently sex fewer birds than I used to.

D725947 Goldfinch. This bird was just completing its primary moult and in conjunction with the adult tail shape made ageing straightforward. As for its sex most of the characters lean towards female except for red extending well behind the eye. This is one of those ambiguous birds but on balance I would expect it to prove to be a female if retrapped during the breeding season. Trouble is most of us don't conveniently retrap such birds during the breeding season to be able to confirm their sex.

D725377 juvenile Goldfinch. A probable male even though the red feathers of the face are still growing. Black nasal hairs, neatly fringed black lesser coverts and broad, pure black stripe to rear of crown are generally male features. The 2 old greater coverts and pointed shape of the tail being obvious juvenile features. This bird has 3 white sub-terminal patches on the tail. This has been put forward as an adult feature in some published work and a feature of males in a more recent paper. I think it will prove to be a predominantly male feature but not exclusively so and have other photos that I think will prove that. I now don't think there is one plumage feature or a combination of features that will ever allow the sexing of all Goldfinches. Easy ones will always be easy but there will always be a significant proportion of ambiguous individuals that should be left unsexed.
The much forecast storm doesn't seem to be heading our way now with no rain and hardly a leaf moving on the trees as I type. It looks like it will track across the south of the country and it remains to be seen if it will live up to any of the hype it has been given over the past few days. If we don't get the wind and rain perhaps I will kick up a little storm of my own with my views on ageing and sexing Goldfinches.

I nearly forgot to mention that I nipped on to Orrell Water Park this afternoon to check through the Black-headed Gulls. The only ringed bird amongst the 75 or so present was the German ringed bird that I recorded 14 times last winter. Interestingly the first record last year was also on the 27th of October! The previously published recovery details can be found by clicking here.

IA141745 Black-headed Gull Orrell Water Park 27/10/13

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