Limber up for Big Garden Birdwatch!

Here it comes, that annual gargantuan fixture on the calendar when we all can help chart the rise (hopefully) and fall (hopefully not) of garden birds across the country. It's Big Garden Birdwatch time!

You'll know this, but for one hour this Saturday, Sunday and Monday, we ask the nation to choose a comfy vantage point overlooking their garden, balcony, yard, or failing that a local park, and record the maximum count of each species that is seen perched. No flyovers; no composite counts over the course of the hour. Just peak counts.

I know you love to challenge yourself, so I thought today I'd give you this testing trio on the feeder outside my study window this week, just to get your identification skills finely honed ready for the weekend.

I realise it is made extra difficutl by being a photo on a dreary grey day taken through glass, but that could exactly your conditions this weekend! And you'll have noticedthat none of the birds are looking at you, just to make it even more difficult.

I'm going to offer 2 points for the bird bottom right, 3 points middle left and 5 points top back. So, out of 10, how do you think you are doing?

This is where I put some big gaps in so your eyes don't glance down the page to the answers!

But what I can tell you at this point is that all three birds have a big Big Garden Birdwatch story to tell.

So, bottom right, a bird that always comes top of the Big Garden Birdwatch charts each year, at least for the last decade or so, and yet is on the Red List because of how far its populations have fallen. It gives you a good sense of how abundant they must once have been, and even in the count last year, they were only seen in 61% of gardens.

So, two points for identifying the house sparrow, what many people think of as a 'little brown job' but actually that back is a rather attractive mix of chestnut and black streaks.

Middle left, this once common garden bird had fallen to number 19 in the national Big Garden Birdwatch list last year. And I'm rather fearful it will drop even further this year. The disease trichomonosis is devastating its populations, which is why it is so important to keep feeding stations and birdbaths clean.

The identification feature that stands out from behind on what is otherwise quite a drab bird is that moss-green rump, but note too the yellow-green flash along the wing edge.

Here it is in rather a more revealing view: the beak is chunky and pinkish, typical of a finch, but still it is that wing flash that is perhaps the defining feature. This is a female Greenfinch - the male would have a much stronger green wash across the whole plumage. Three points in the bag?

And so finally our 5-pointer. If you were struggling, then maybe this next photo will help.

Our only plain grey-brown bird with a ginger topknot is the female Blackcap. Males would look very similar but a couple of shades greyer and of course with a black cap.

They were at number 30 in the Big Garden Birdwatch list last year, but even that is amazing because when Big Garden Birdwatch started in 1979 this would have been a rare winter bird indeed. UK numbers in winter of this insect-eating warbler are on the rise, in particular because they have adapted to visit bird feeding stations and have adopted new migratory patterns. Indeed, it was shown only very recently that some French Blackcaps are now migrating NORTH to the UK for the winter, the opposite direction you'd expect of our migrants.

So what will Big Garden Birdwatch show this year? That's exactly what your data will tell us!