Welcome to Quiz Night Tuesday
Tonight's question is all about sunflower hearts and Goldfinch. Last year I noticed a surge in the number of Goldfinch in the garden from the middle of Autumn. Much bigger numbers than in previous years, so I decided to track the Goldfinch a bit more closely by monitoring their numbers and the amount of food they were eating each day.
I learnt a lot from the study last year and am therefore going to repeat it more accurately this year in an attempt to calculate the amount of energy Goldfinch get from a garden feeder in the Autumn/Winter months.
So your question for tonight, and it is a very tricky one, is as follows:
How many individual sunflower hearts (individual kernels not kilos) did the Goldfinch eat in the 7 day period from 11th October - 17th October 2015. I will help you out with a couple more facts:
- we had approx a staggering 120 Goldfinch visiting the garden each day
- it was a dry, sunny week
- we were using one massive 12 port feeder for the sunflower hearts
- and finally, this is what a kilo of sunflower hearts looks like
The person with the closest answer will win...................a bag of sunflower hearts of course.
When you post your answer, it would also be great if you could mention what your thought process was in working it out. You have until Thursday evening to post your answers.
And the answer is:
First of all, for a full explanation on last year's Goldfinch survey, please click here.
So here is how I worked out the final answer.
From from 11th October - 17th October 2015 the Goldfinch ate 7.92kg of Sunflower hearts.
I weighed out 50g of sunflower hearts and counted 1120 kernels
So 22,400 in 1kg
7.92 kg x 22,400 kernels = 117,408 kernels
So the answer is 117,408 kernels.
And the answer is:
First of all, for a full explanation on last year's Goldfinch survey, please click here.
So here is how I worked out the final answer.
From from 11th October - 17th October 2015 the Goldfinch ate 7.92kg of Sunflower hearts.
I weighed out 50g of sunflower hearts and counted 1120 kernels
So 22,400 in 1kg
7.92 kg x 22,400 kernels = 117,408 kernels
So the answer is 117,408 kernels.
So the closest to this was Hugh with an answer of 174,804 kernels.
Thanks to everyone for having a go and well done Hugh, a bag of sunflower hearts will be on it's way soon.
7800 seeds. But double the amount dropped on the floor :-)
ReplyDeleteLOL!
Deletethere is a big tray under the feeder that catches all the dropped seeds and get eating by the goldfinch
DeleteSorry I did my sums wrong, my answer should 216,840
DeleteWell, it is a well-known fact that there are 27.8 sunflower kernels per gram, so that makes 27,800 per kilogram ... And I reckon you got through 17 kg in the week. So that's 17 x 27,800 = 472,600 seeds.
ReplyDeleteMy answer is 417.000 and that book is a great read
ReplyDeleteHi Fin
ReplyDeleteBritish Standard Sunflower Kernels weigh in at 28.8 per gram (not Hugh's 27.8, although he's not far out!). However, that fact is totally irrelevent to my calculations.
My Goldfinches each get through 57.8 kernels a day. However, 70% of these go on the floor as crumbs, so the actual daily consumption by the birds is 17.34 kernels per bird per day. My Goldfinches are Midlands Goldfinches, and are probably less needy (or should that be greedy?) than your Northern Goldfinches, so we'll allow another 20% for yours, making your consumption 20.81 kernels per bird per day. Multiply this by your 120 birds and that makes 2,496.96 kernels per day. Multiply this by 8 days in the week (according to the Beatles you get 8 days a week up north) and you get 19,975.68 kernels.
My answer is, therefore, 19,975.68 kernels - or somewhere between a ten thousand and forty thousand, but definitely not as high as the previous two suggestions, unless you are allowing the consumption by other birds in there too!
Thanks for a fun quiz - - - Richard
Are you sure you're not starving those goldfinches, Richard? 17.34 kernels PER HOUR is surely closer to the recommended standard intake. Also, you appear to be using seriously underweight sunflower seeds.
DeleteI'm the one that's starving, Hugh! - spent all day and night counting the seeds in a 25kg sack, and didn't have time to eat or drink - and I din't even use the result in calculating the answer to Fin's question. I must be mad!!
DeleteCan I have another go? Based on the Official Recommended Intake of 17.34 kernels per hour (Midlands) = 20.81 in Cheshire, and allowing 10 hours of feeding time per day in October, and assuming all 120 goldfinches are feeding only on the Wilde feeder, that's 20.81 x 10 x 120 kernels per day, which is 20.81 x 10 x 120 x 7 (no, not 8) = 174,804 kernels in the week. All assuming, of course, that they are proper full-size sunflower kernels suitable for Cheshire birds (27.8 per gram), not the substandard fare that is on offer in the Midlands. Maybe you only got through 6.288 kilograms, not 17 as previously estimated.
ReplyDeleteInteresting ... In truth, genuinely interesting. Your sunflower seeds seem to be heavier than mine, Fin. Only 22.4 per gram, compared with my 27.8. But you counted 50 grams, and I only counted 2 grams (!), so my figure is not very reliable. 117,408 seeds in a week = 16,773 per day. With 120 birds that's 140 seeds per bird per day, which is about 14 seeds per hour of daylight.
ReplyDeleteMaybe (to answer Richard) we're all mad.
Hugh
I have a bird brain when it come to math. And not a crow sized one either. So, I just enjoyed your post. And your blog visit!
ReplyDelete