Tag Archives: trichomonosis

All the other garden birds…

In the last post I described the tits visiting my bird feeders. But of course they’re not the only species fattening up in the garden so this post is about the others. The berries and other food from the countryside are now becoming rather more scarce so greater numbers of more species are appearing.

One of the first to arrive, which has been around for a couple of months now, was my resident robin (Erithacus rubecula, Dansk: rødhals). Robins are fiercely territorial and this little guy being  no exception makes it clear that my garden is his manor, in fact it’s fair to say he’s a complete thug. He only picks on birds of a similar size or smaller and he won’t tolerate them for even a second. The two species he seems to dislike most are the dunnocks (Prunella modularis, Dansk jernspurv) and the coal tits (Periparus ater, Dansk: sortmejse) who have the temerity to enter his domain and he chases and beats them up remorselessly. Earlier this afternoon another robin turned up and I expected real fireworks as I’ve heard stories of rival robins fighting to the death and scalping each other! The fighting this time was restricted to a short chase and a bit of posturing and then it was all over, fortunately no injuries or fatalities were sustained.

A source of much concern this winter has been the absence of goldfinches (Carduelis carduelis, Dansk: stillits). I have a niger seed feeder for them which I keep full, but they ignored it until a few weeks ago, but even then there was only ever one or two making the occasional visit whereas previously they would be feeding there every day, often five or six at a time. And then a sparrowhawk (Accipiter nisus, Dansk: spurvehøg) attacked a goldfinch on the feeder and I didn’t see another one until a few days ago. I don’t know if the memory of the sparrowhawk was enough to keep them away but they have been conspicuous by their absence.

A lone goldfinch feeding on niger seed

There is a tall old tree 10 metres from my garden which I often see flocks of 20+ goldfinches in but they just don’t seem to want to drop down onto the feeder. Maybe if the weather turns icy they’ll alter their behaviour as food gets even more difficult to find.

Greenfinch (Carduelis chloris, Dansk:  grønirisk)

I’m always pleased to see greenfinches because they’re one of my favourite small birds and also because their numbers have been under threat from a nasty parasitic infection called ‘trichomonosis‘ which I posted about last year. So this little chap was very welcome. I was surprised to see him sitting on the niger seed feeder, but he wasn’t eating the seed, he was waiting for an opportunity to descend onto the seed tray which was already occupied.

The small birds usually have free access to the seed tray but occasionally it’s fully occupied by a pair of collared doves:

Collared dove (Streptopelia decaocto, Dansk: tyrkedue)

This was one of a pair and its partner was just out of shot further along the fence. A lot of folk seem to be very unimpressed by collared doves but I like having them around and I particularly like this guy with his feathers ruffled by the wind.

Previously I’ve been taking my close ups with a Nikon D40x and a Nikon 70-300mm zoom lens. This has been a really good combination, it’s small and light and therefore easily portable and has performed really well. But last year I bought a Canon 7D because I wanted to upgrade my camera body to one which is more robust and with more capability. I chose Canon rather than Nikon because the lens I thought most appropriate for what I needed was the 80-400mm telephoto zoom, but every review I read of it was that it was no good at all for wildlife photography because the autofocussing speed was much too slow. So I reckon Nikon missed a trick there because Canon have the 100-400mm L series telephoto zoom for around the same price as the Nikon lens which I decided to go for because it is supposed to be good for wildlife.


Wood pigeon (Columba palumbus, Dansk: ringdue) keeping the small songbirds away from the seed tray all by himself

All the photographs in this post except for the greenfinch were taken in murky conditions using my new Canon lens and I’m very pleased with the image quality. So now I’m looking forward to experimenting with it further afield. I’ll post the results as soon as I can.

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Carduelis (or Chloris) chloris

A sound I hear frequently at the moment when I open a door or a window which stands out from all other birdcalls is the call of the male greenfinch. It’s quite variable in tone from fairly high pitched, as in the recording here, to lower pitched where it almost sounds like a whirring mechanical toy.

The bird in these pictures has a reddish hue to it because it was being lit by the evening sun as it was getting lower in the sky, and also from the reflected light of the rusty ironwork and insulators of the electricity supply cables:


Greenfinch male calling from the top of a telegraph pole

The female greenfinch is similar to the male but her colours are much more drab, she is darker grey/brown without the vibrant green of the male.

The greenfinch is a resident breeder in the UK and can be found in gardens and parks at all times of the year feeding on bigger seeds and sometimes insects when rearing youngsters. It has a chunky beak which is typical of finches and is custom built for cracking open seeds.

The taxonomic name for the greenfinch is listed in some references as ‘Carduelis chloris‘, as in my RSPB ‘Complete Birds of Britain and Europe’ by Rob Hume published in 2002, (RSPB – Royal Society for the protection of Birds) ISBN 0751373540, and also in the RSPB Bird Identifier website. But in the BTO BirdFacts website (BTO – British Trust for Ornithology) and in my Collins Bird Guide 2nd edition from 2010, ISBN 978 0 00 726726 2, it is listed as ‘Chloris chloris‘ (Dansk: grønirisk). Somewhat confusingly the BTO entry goes on to explain that the name derives from ‘carduelis‘ meaning ‘goldfinch’ and the Greek ‘khloros‘ meaning ‘green’. So it appears that the two names may be interchangeable. Incidentally, the chemical element chlorine also derives its name from khloros as it exists as a green gas.

He’s turned round to keep on eye on me – his seed-cracking beak clearly visible

The poor old greenfinch has taken a bit of a battering in the last few years since 2005 from the trichomonad parasite which causes a disease called trichomonosis. This microscopic parasite lives in the upper digestive tracts of several birds species including other finches, house sparrows (Passer domesticus, Dansk:  gråspurv) and pigeons and doves. I’ve heard that feeders may become contaminated by pigeons from where it infects the smaller birds. It’s particularly unpleasant (as are most parasitic infestations!) because it causes the throat to swell to the point where the birds can’t swallow so they eventually die of starvation.

Fortunately I’ve never seen any evidence of infected birds but if you think you may have a problem you can click here for the RSPB advice sheet which has details on how to identify the problem and how best to deal with it.