Birds, butterflies and moths

[ChrisC]

i'm pretty sure that in my 43 years that i have never seen a bird eat a butterfly in the UK. but moths, yes, plenty of times (i had the displeasure of watching a robin take an elephant hawkmoth in the garden) so i was wondering why don't more birds take butterflies, do they taste that much different to moths? i know some do taste quite bad for birds eg whites, but it's not like a small heath has bright warning colours, or speckled wood for that matter. has any research been done how birds see butterfly wings? is it a case similar to how bees see flowers in UV? Or is just that generation after generation of parent bird hasn't taught the youngsters to catch them.

Any thoughts?

Chris

[David M]

I too have never see a bird take a butterfly*, though I remember once seeing a sparrow flying after a Tortoiseshell without its desired end result. In fact, the only butterfly I've ever seen killed and eaten by a bird was when one of our bloody chickens* got a Speckled Wood in the garden a couple of years ago.

It's amazing when you consider just how many butterflies sport wings ragged as a result of bird strikes that such a sighting is so uncommon.

[Gibster]

Hiya Chris, presumably you're referring only to adult butterflies?

I've certainly seen Spotted Flycatchers take butterflies. Plus I quite commonly find butterfly wings (or parts of) on the ground. Usually Red Admirals, for some reason. Doubtless some will be spider/insectivorous mammal victims, but many must be bird kills? Last week I watched a Noctuid dragging a Carabid beetle in circles through the grass. Eventually it escaped leaving a somewhat baffled beetle at my feet!

Colour-definition is known to be particularly well developed in birds, much more so than in mammals. Birds see colours much more vividly and sharply than we do, for instance. Certain species are now known to also be able to see in the UV spectrum. Not sure what bearing that has on this subject though, lol.

Cheers,

Gibster.

[Dave McCormick]

I have never seen a bird take an adult butterfly either, I have seen common darter dragonflies chasing red admirals and small tortoiseshells about trying to catch and eat them and once saw a four-spotted chaser, chasing a dark green fritillary trying to grab it, was quite a sight, especially at the same time the fritillary was being chased by two male common blues!

I quite commonly find butterfly wings (or parts of) on the ground. Usually Red Admirals, for some reason.

For me its small tortoiseshell wing fragments I see, never really see other species in like that.

[Padfield]

I've frequently seen birds take butterflies - most commonly whites but also other species. Very often the butterfly gets away, after a brief mid-air skirmish that often involves quite spectacular displays of wings and tail as the bird attempts to spin to the jerky path of the butterfly (butterflies can change direction with a wing-beat, whereas birds, carrying more momentum, cannot)!

This autumn, several birds, including black redstarts and a regular robin, hung around my butterfly nectaring paddock, sitting in the low bushes beloved of green hairstreaks in the spring, occasionally zooming out after walls and small whites. By the end of the season, most remaining walls had bites taken out of their wings, often at the eyespots.

Guy

[Paul Wetton]

Whilst in Switzerland we found large numbers of Scarce Swallowtail wings on the ground at salt lick sites and I can only presume these were the victims of birds. We found one individual butterfly with a huge hole at the base of one wing making it impossible to fly.
I have seen wasps taking butterflies in the autumn and they do remove the wings.

[Gibster]

One other thing that springs to mind, butterflies are all active during the day whereas many moths are sleeping/sitting tight, hence will fall easily to a foraging bird.

Almost all insectivorous birds in Britain actively forage during the hours of daylight, Nightjars being the notable exception (although admittedly some other birds also catch insects at night, eg Little Owl). Only a relatively small proportion of British birds are capable of chasing down and successfully catching a jinking butterfly in mid-air, but a resting moth is a much easier target, plus they very often only flush a short distance. And a large moth species, such as a hawkmoth or Lasiocampid, may need to warm up the flight muscles before it is even capable of flying.

So maybe its simply a case of most moths are easier to catch? (Good luck to any bird chasing a male Eggar across the heathland though, I doubt even a Hobby would come close!!!) Plus I think there are a lot more moths (numerically) than butterflies in most habitats.

Cheers,

Gibster.

[Gibster]

I have seen wasps taking butterflies in the autumn and they do remove the wings.

In Nicaragua we watched huge orange wasps taking large tadpoles from evaporating pools, actually lifting them out of the mud and flying off with them!!! Yukk