Friday, 24 October 2014

Why do we feed garden birds?

ResearchBlogging.orgA couple of Goldfinches came to the nyger seed feeder. A Blackbird was sat on the rowan, which barely has any berries left, while a Dunnock and a Robin pecked at the bits of bread left by a Woodpigeon and a couple of Collared Doves visiting earlier. Yes, I do put food out for the birds. Bread crusts that the kids leave behind after breakfast, mixed seeds, peanuts. I stopped stocking the bird table with seeds though, as Woodpigeons and Collared doves wolf them down in a sitting.
 But I do feel conflicted putting food out for birds. It is good for us or is it good for the birds? Yes, I do enjoy watching the birds coming to food I put out, but I much rather watch the birds that come to the garden for its intrinsic value: long-tailed tits hunting aphids in the bushes, blue tits looking for spiders on the wall, or blackbirds feeding on the rowan and cotoneaster berries or the fallen apples, or swifts and house martins flying overhead hunting insects. I also worry that I don't clean the feeders as often as I should.
 A recent survey in New Zealand revealed that introduced species were more likely to benefit from supplementary feeding than native ones (House Sparrows and Blackbirds were the top species visiting gardens), questioning the conservation value of bird feeding. Here, we have proportionally fewer introduced species in gardens, but most of the birds which benefit from supplementary garden feeding have increasing of stable populations. Even if a few species in decline regularly come to gardens*, is this really the way we want to help them? providing a few scraps instead of good habitats?
 We spend a lot of money on feeding birds. According to the BBC, about £200 million is spent every year on bird food and bird feeding in Britain. About a third of us regularly top up our bird feeders. To give you an idea of how much money this is, compare to the 'meagre' about £25 million annual income of the Wildlife Trusts. Imagine how much real conservation could be done with this money. Wouldn't it be better if we spent our collective money converting the same surfaces of land that we use to grow bird seed into new meadows, woodland and wetlands bursting with wildlife?
  There are also costs to birds associated to giving the birds supplementary food, amongst them disease. Dirty bird baths and feeders can transmit disease. Trichomonosis and Salmonella outbreaks might have been responsible for the recent declines in Greenfinch, Chaffinch and House Sparrow populations.
 Supplementary feeding has some interesting consequences. We are basically generating a new, often reliable food source, often during winter, when birds may find it difficult to find food. Birds are adaptable, and have started using this resource. The Goldfinch has spectacularly increased in numbers as a garden visitor. In the 90s it was present in less than 15% of gardens, while now is reported in about 50% of them. Much of this increase appears to stem from provision of Nyger seed, which is also encouraging Redpolls and Siskins into gardens. Once individuals find, and learn to use a resource, the habit is transmitted to the next generation. Another unforeseeable consequence of supplementary garden feeding is the recent change in migratory habits of the Blackcap. Blackcaps have become a common winter visitor in gardens. These birds are migrants from Germany, which move to the UK instead of the Mediterranean (I've covered this before in The Ratting Crow). We are indeed changing birds in unexpected ways by feeding them.
 The same New Zealand study I mentioned before examined the motivation behind bird feeding and found that people feed the birds because birds give them happiness (50% of respondents). As feeding birds brings us joy, it is unlikely to stop. I do look forward to the visiting Goldfinches. This summer, they brought a new generation of fledged young to the feeders, which will likely carry on visiting for years to come.

*Common declining garden species as found in the BTO Garden Survey Results include House Sparrow, Starling, Greenfinch and Song Thrush.

More information
Galbraith, J., Beggs, J., Jones, D., McNaughton, E., Krull, C., & Stanley, M. (2014). Risks and drivers of wild bird feeding in urban areas of New Zealand Biological Conservation, 180, 64-74 DOI: 10.1016/j.biocon.2014.09.038


  1. This is a very thought provoking post Africa. I recall some time back, a report showing that we were killing our wild birds by giving them poor quality food that was somehow infected. It really is worrying, knowing if the food is good enough in quality. I no longer put food out unless the weather is severe in winter, but that is a financial constraint.

  2. Thank you Toffee Apple. The post has been in the works for quite a while. Somehow it is like we want to domesticate wildlife. Food quality is an issue I didn't touch on, it is really a big topic, probably deserving more posts.

  3. Very interesting article (and blog!) - thanks for all the info, really thought-provoking.
    Whilst I provide birdfood and water on a daily basis, at the same time I try to keep a wildlife friendly garden, small though it is, so there are plenty of berries, undergrowth, hedges, seed-producing plants and insects, slugs, etc. thriving in it naturally. I always find it interesting to watch how the birds vary their diets and don't just stick to the feeders even though that might be the easy option. Watching them is very much a pleasure for me but also I think the motivation is that I want to do 'my bit' as far as I can. As an individual I feel I can't change their loss of habitat to housing, or stop the destruction of hedgerows, the felling of trees, the intensity of farming methods, etc., etc. - so I try to address the things that concern me as far as I can with the little piece of outdoor space that I can share with them. Maybe that is motivation for a lot of people? We may donate money and join the right organisations individually but we still can't control how the funds are spent, whereas when we can do something directly it feels more positive, more instant. Then we can also enjoy the direct rewards of seeing well-fed birds and them rearing successful broods in our habitats. Ideally I would like to be able to do both and I do hope that perhaps fostering people's interest in birds by feeding them may lead to greater interest and awareness and thus to more contributions to campaigns and membership of conservation groups too. Just a thought!

  4. Perhaps the urban environment is so artificial that even the planting of native berry-bearing trees and the encouragement of weeds and wild places does little to restore the natural order. In such a setting, adding bird feeders can hardly be considered wrong, as long as they are carefully maintained to avoid spreading disease.

    The worst contagious condition that affects my local birds in Kensington Gardens is the Chaffinch foot fungus. Nearly all the Chaffinches have it to some degree. It is certainly exacerbated by the feeders occasionally filled and poorly maintained by the park staff -- the only person who knew what he was doing has retired. Some of these feeders have a floor inside the pigeon-proof mesh on which Chaffinches walk, and this must be a complete cesspit full of all kinds of spores and bacteria. I am glad to say that when Chaffinches come to feed from my hand, they always hover and grab seeds without putting their feet down, so at least I am not spreading the fungus.

    We have only seen the beginning of the sterilisation of what used to be the countryside. The EU has insanely licensed diclofenac, which will do for our carrion-eating birds what it has done for the vultures of India, with grave side effects that will radiate through the ecosystem. And it is only a matter of time before 'Roundup-ready' crops smash what remains of our native wild plants. I fear that many bird species will become confined to the relatively benign habitat of towns. We need to do what we can to keep them going.

  5. Thank you C. and Ralph for your thoughtful comments. I agree that everything we do changes the environment, but bird feeders is a massive evolutionary and ecological experiment and we should be aware of the pros and cons. I am perhaps more optimistic than Ralph about the EU. There is an ongoing campaign to ban diclofenac ( and although farmland birds are going to have a tough time as agriculture intensifies we must remember this is already an altered environment. It is true that we tend to feel like we are doing our 'bit' for the environment, but urban birds benefiting from feeding are a small proportion of our bird diversity.