[Ollie]

I occasionally use flash for bird photography in daylight winter conditions when it is dull and overcast. I have never seen any reaction to the flash from any of the birds that I have photographed and as mentioned by Malcom earlier in the thread I generally have the flash exposure compensation set to at least - 2/3rds of a stop sometimes more.

Again Malcom is right in saying that too much flash will only give you a bad photo anyway. If you can tell the photo has been taken using flash without looking at the exif details then the flash in my opinion has been overdone.

I have photographed birds from my bedroom window in winter using flash and although I am pretty close to them they don't take flight or even flinch at the flash often staying perched to allow several shots as they do without using flash.

As for insects, most of you that are regular on here will know that I use flash for my macro insect photography even on bright days. I always use a diffuser and again the flash is set to - compensation and this coupled with the diffuser I think does no harm to the insect in any way. I certainly seem to be able to get several shots often from differing angles of the same insect before it decides to move off and if the flash was having any adverse effect on the insects I think they would take flight much sooner.

If I thought by using flash that I was compromising any bird or insects well being then I would certainly not use it.