how to stop dog catching butterflies and bees?

[ender]

He did it last summer so was mostly on lead in the garden. I thought he might have grown out of it now he's 14 months old but has just killed a lovely Red Admiral, first we've seen this year. He caught it and played with it till it was dead . Any ideas how to train him out of this?

My dog chases anything that flies to the point of obsession. He rarely catches anything though.

We asked our dog trainer what to do and she said:
distract the dog each time
reward the dog if it sees something to chase but doesn't
teach a leave it command

None of this works for our dog because chasing flies is more rewarding than anything else. We make sure to use a fly curtain in summer so the house is safe (he will run into things) and try interrupt him when outside.

I wouldn't mind flies and spiders but butterflies is a bit of a shame. However he might think twice once he's snapped at a bee or a wasp and it's stung him in the mouth. They do like to learn by experience. Bit like children in that respect.

Ilove I don't agree about the spiders, there is nothing worse than seeing housespider legs hanging out of your dogs mouth!

My dog loves chasing bees. Every summer she gets stung on the tongue/nose. She will not listen to anything we say/do to her & will continue to try and catch another even though she's just been stung. She's 13yrs so it's definitely not to change anytime soon :)

Thanks for replies. Definitely need to sort it out so will try distraction and rewarding.
We had a bumble bee nest in the house eaves last summer and I loved watching them bumbling about until we got dog in August. He caught every one he saw and was was never stung, I kept hoping he would be so it'd put him off, had Piriton standing by. He has has to work a bit harder to catch butterflies but enjoys the chase and leaping about.