Just a quick field note on foot use. I wasn't aware on Long-tailed tit foot use before, so I was very pleased to watch this behaviour. Sun flower hearts had been placed atop posts on a nature reserve and a flock of Long tailed tits was feeding on them. Individuals will pick a sunflower seed and jump to a branch t
o hang from it with one foot while holding the seed on the other food to feed on it. Other tits hold seeds between their feet while they feed, perching on a branch. Is it that Long-tailed tits are not able to balance on a branch while bending down on their feet, maybe because of their long tail? I saw the behaviour repeatedly, and I should have taken a video, but I just got this shot from behind that shows the foot holding onto the branch and the other with the seed on it. What call my attention was the fact that they had to jump to a branch to hang from in a premeditated way so that they could feed. The
Two in the Bush blog also describes this behaviour, with much better photos. Hanging from one leg poses no issue for these tiny acrobatic birds!
Given that long-tailed tits are not true tits (nor particularly closely related to them), it's perhaps not unexpected that they would have divergent feeding strategies. Use of the foot in reaching for and grasping objects while foraging appears to be a widespread behavior in aegithalids (e.g.: some species grab clumps of leaves with one foot to expose whatever's behind them). It could certainly be true though that their proportions allow them to perform this more easily than other, similarly-sized songbirds; I'm not aware of any research that's been done on that front.
ReplyDeleteHI Albertonikus, thank you for your comment, I wasn't aware of foot use on other relatives. I'd be happy to hear about any research on this if you find one!
ReplyDeleteI don't know where the behavior was originally reported in scientific literature, but Handbook of the Birds of the World mentions, "[The Bushtit] frequently hangs upside-down and by one foot, and it will use a foot to bend back a leaf so as to expose the central area of a foliage clump."
DeleteI had a belated thought about this. True tits, when perched on a branch using their long middle (no.3) toe to grip, can raise their shorter inner (no.2) toe off the branch, which allows them to grip a seed in a convenient position for pecking. I was looking through pictures of perched Long-tailed Tits, and I can't find any that shows their inner toe in this position. Maybe they can't do it?
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