Wild Bird Seed Survey

17 January 2011 I'm sick of wasting money on birdseed that birds in my gaden don't eat!

This is a survey of what seeds birds do or do not eat in my garden in rural Somerset, UK. My objective is to learn what food best suits the birds in my garden - and my wallet.

There are 3 questions I want to answer.

  1. Which brand of mixed seed do the birds prefer?
  2. Would I be better off buying separate seeds?
  3. If so, which seeds are preferred?

In December 2010 we had unusually cold weather when the images above and below were taken. Birds were tempted to feed in my garden in large numbers. The bulk of the food is normally placed in feeders, but in the image above food was spread along the top of the low wall. No sooner was this done than it was covered by subsequent snow falls. To solve the problem I swept a bit of path clear, placed a glass topped table over it and scattered bird seed under. The food in question was Harrison's All Seasons Wild Bird Food. I was rather surprised to note at the end of the day that the bulk of the food remained uneaten in spite of the very harsh weather. There had been plenty of birds hopping around and pecking and scratching at it, so they were not deterred by the table looming overhead etc. Image 2 is of the uneaten food.

Among the uneaten seeds were wheat, oats, peas, maize, and various small round seeds resembling yellow and red millet and rape. Wheat predominated.

Below is a list, in no particular order, of birds that are commonly seen on or around seed feeders in my garden. The operative word is ‘commonly’; a week or so ago I saw a Great Spotted Woodpecker - Dendrocopos major - on a seed feeder, but I think it was just investigating. It normally confines its efforts to the peanuts which are not a part of this survey.

  • Blackbird - Turdus merula
  • Blue tit - Parus caeruleus
  • Coal tit - Parus ater
  • Great tit - Parus major
  • Chaffinch - Fringilla coelebs
  • Greenfinch - Carduelis chloris
  • Goldfinch - Carduelis carduelis
  • Dunnock - Prunella modularis
  • House sparrow - Passer domesticus
  • Robin - Erithacus rubecula
  • Starling - Sturnus vulgaris
  • Wood pigeon - Columba palumbus
  • Collared dove - Streptopelia decaocto
  • Pheasant - Phasianus colchicus

I use mainly two sorts of feed; peanuts and packaged mixed seeds. As I am only concerned with seed I have listed above only those birds that show an interest in seed as opposed to those which only show an interest in peanuts or other food. For example, although bullfinches - Pyrrhula pyrrhula - regularly visit my garden I have never seen them on the seed feeders, in spite of bullfinches featuring prominently on the packaging of Harrison's All Seasons Wild Bird Food. On 27 Jan 2011, on two separate occasions, I spent 5 minutes watching a female bullfinch gorging on Amaryllis shoots less than two feet from a seed feeder receiving heavy traffic from other birds. The bullfinch completely ignored the seed in the feeder and the spilled seed on the ground. Image 3 shows a random sample of 4 oz of Harrison's All Seasons Wild Bird Food.

I sorted the above sample into its various constituent grains. Image 4 is of the sample shown in Image 3 after sorting - testimony that I need to get out more. Starting from top left of Image 4 and going clockwise I identified the seeds as follows; black sunflower; unidentified ‘grasses’ and dross; split peas; mixed rape and red and yellow millet and possibly other small seeds; red dari; un-milled oats; and cut maize. In the centre is wheat.

The sample in Images 3 and 4 contained approximately the following weights and percentages of seeds. In case anyone is counting they were weighed in identical bags. 8 bags weigh slightly < ½ oz. [< = less than.]

  • 2½ oz wheat = 55%
  • < ½ oz rape, millet = < 11%
  • < ½ oz maize = < 11%
  • ¼ oz peas = 5.5%
  • ¼ oz black sunflower = 5.5%
  • ¼ oz oats = 5.5%
  • < ¼ oz red dari = < 5.5%
  • < ¼ oz dross = < 5.5%

At the time of writing 20 kg of Harrison's All Seasons Wild Bird Food costs £11.34 which is slightly under 57 pence per kg. My guess at this stage was that at least half the feed is uneaten. So the food the birds ate actually cost about £1 per kg. At time of writing I was quoted the following prices for unmixed grain bought by the sack from the same supplier of the bird seed;

  • wheat = 31 p per kg
  • maize = 38 p per kg
  • peas = 44 p per kg
  • black sunflower = £1.12 p per kg
  • oats = 34 p per kg

I was unable to get prices for the other seeds.

In effect, at the above prices and percentages each constituent seed in the All Seasons mix is priced up to approximately £2 per kg or 6 to 7 times their price if bought separately. Food for thought, but not necessarily for the birds.

I decided to conduct some seed trials but before that I needed to refine delivery.

See Pre-Trial 1 to 8 for a gripping account of how to make seed feeders - or not.