Hello Andrew,

I assume you are considering the impact of flash on nocturnal raptors, ie owls etc. My experience photographing nocturnal birds is mostly restricted to my garden where I have photographed Powerful Owls and Tawny Frogmouths. I use manual flash control and have used a Better Beamer when long-range shots are the only option otherwise I see no significant difference between using a standard flash at shorter range and a Better Beamer for long-range shots. Regarding the impact on the birds, I offer the following observations.

The accommodation response of the birds I have worked with is extraordinary. For example, Powerful Owls and Tawny Frogmouths have pupils that close and dilate in a matter of seconds. They can also control the pupil aperture independently so that if you shine a torch on one side of the bird's face, it will quickly close down the pupil aperture while leaving the opposite pupil (in shade) wide open. The birds seem to be quite unconcerned by the torch light and look around for prey as if in darkness. They fly from a perch that is in torchlight to seize prey with uncanny accuracy. I see no adverse impact on hunting and feeding behaviour.

A few years ago I decided to get a red LED torch believing this was 'safer' to use for spotting and photographing nocturnal birds. It works OK but there is a potential problem. When you illuminate a nocturnal bird with a red light it usually leaves its pupil wide open so when you fire the flash the bird's retina gets the full impact. I decided it was better to use a white light LED which caused the bird to close down the pupil to something like daylight adaptation. Then the flash pulse would be no different to using fill-flash on a bird in daylight.

Cheers,

Ian

Thanks Ian,
I was really hoping that you would add to the commentary with a fair slice of your expert knowledge.
Bruce

Thanks very much for your comments Ian. Sounds like you have an amazing backyard....something I miss as we now live in a townhouse with a small courtyard, but I've
re-planted it with bird attractive native plants and also some plants that will give the small birds protection from the noisy mynas and wattlebirds that currently visit.
Re the raptor photography with flash, I'll proceed on a trial and error basis, so if the flash affects the birds I'll just stop using it.
Thanks again Ian, Glenn & Bruce. Cheers Andrew

Hi Guys,
As stated, I did some research on the Web to see if there had been any work done in this area and i couldn't really find anything that was actually backed up by research or reports, however some of the written material was supplied by University grads who made mention of their 'studies' being involved in their conclusions.
I did find plenty of material that is personal opinion and indeed leading to personal hysteria, so it's certainly a decisive subject;
Please find the included sites for further reading:

https://www.audubon.org/news/is-flash-photography-safe-owls

https://www.naturescapes.net/articles/health/flash-photography-and-the-visual-system-of-birds-and-animals/?replytocom=257#respond

HTH,
Bruce

Useful discussion and links, thanks for raising it.

Thanks all for your comments on my query: esp Bruce for his research of the limited online data, Ian for his personal observations and Glenn for his rational advice.
Obviously no hard and fast rules but gleaned from the replies and their content three comments resonate with me:
1. “The subject is more important than the photo,”
2. "... the use of fill-flash on animals and birds is not likely to have any effect on their visual systems..."
3. ".....if the use of flash appears to be causing a reaction by the bird, it would be wise to discontinue...."
In the absence of other ethical guidelines, I'll be guided by the mantra above.
Thanks all and Cheers Andrew