As regular readers will know, my garden is blessed with a large flock of tree sparrows. I’ve lived with tree sparrows now for over eighteen months, but I haven’t really got to the bottom of the question: what do they like to eat?
Tree sparrows dominate my garden: this week I’ve counted over forty, while the next most common bird this week is the dunnock at three. And they don’t just come for the food. My house backs onto a field and I have a long and very overgrown hedge, which they love. Throughout this winter the minimum tree sparrow number has been forty. The maximum number of the next most numerous bird was wood pigeon at a (very unusual) twelve.
The tree sparrows love the hanging feeders, but it hasn’t escaped my attention that a lot of the food gets chucked on the floor. Are they just messy, or are they chucking out the bits they don’t want to eat? I decided to find out by trying a food experiment.
I buy my bird food in bulk from Vine House Farm. They don’t do a sparrow mix and their standard mixed seed is relatively low in millet, which sparrows are supposed to love. So I buy red and white millet separately and mix it into the standard mix. If sparrows don’t eat sunflower or wheat, given that they outnumber my other visitors two to one, I’m probably buying the wrong feed.
My cunning plan was to place piles of seed on the patio where I can watch from my office window, while still feeding their regular mix from the feeders. They completely ignored the piles for nearly a week, by which time the blackbirds had scattered the piles all over the place.
I tried again. The piles were: black sunflower mix, white millet, red millet. The dunnocks were first to try, and showed no preference. The blackbirds were next and preferred the sunflower mix. The tree sparrows. Well, they ate from whatever pile of food their friends were feeding from. And they seemed really spooked by the food piles.
Could my sparrows really be scared of a change in seed mix? I scattered some mixed seed on the patio to find out. With this return to normal routine they flocked in.
I tried my experiment again, this time using the hanging feeders.
I filled one feeder with sunflower mix, one with white millet and one with red millet. It took about three days before the sparrows would go near any of them, and they went to the familiar mixed seed first. Once they’d got used to the feeders they showed a slight preference for the red millet. But only slight. However, there was much less wasted seed under the millet feeders.
So what have I learned? Have I answered the question: what do tree sparrows like to eat? I’m pretty sure they like red millet the best, but they didn’t show the strong preference I was expecting. What I did learn was that for a tree sparrow, other things are much more important than sampling their favourite food.
Tree sparrows don’t like change. They don’t like novelty. They like things today to be the same as they were yesterday. They like to do things together. None of them wants to be the first to try out something new. Only once the bravest birds have checked out the new food or feeder will they get properly stuck in…
…I think the tree sparrow motto is definitely “safety first”.