Recent content by FeatherGlow

I've got the lights, but haven't found a cooperative heron yet! I'll eventually get a light on one. I see herons out there all the time, but they are wary. But it could have been any bird. I estimated it was larger than a turkey vulture. In case anyone is exploring this someday. My sighting...

I apologize for getting too speculative and argumentative. I don't have the answers and am trying to determine if it is even possible and explore conditions under which it might be. I hypothesize that a blue light fluorescent effect might occasionally happen in the twilight. But it would...

Thanks, berkeman. I am relinking the Nature article on light wavelengths in twilight to get this back on track. My reading of this article suggests that early astronomical twilight in a rural area during the dark moon does have wavelengths dominated by the 470-ish nanometer range. Am I...

True. But I've reviewed many alleged observations of this stuff from the 19th and early 20th centuries.

I don't have a heron to test it, but yes it should be easy. I also think that time-lapse cameras taking pictures of various fluorescent pigments at twilight would be interesting.

Herons are well known for spreading this powder down all over themselves. It is said that they do this to keep from getting fish slime on them. I suspect that they do it because they have been fishing with lights and bait for millions of years.

My hunch is that the powder down on herons has undocumented fluorescence. My hunch is that people can see this under certain twilight conditions. But it is rarer today because of light pollution.

Regarding that night heron... This is from "Birds of Massachusetts" by E. H. Forbush in 1925.

I wasn't clear in the previous post. Barn owls are known to intentionally reflect moonlight as part of their hunting strategy. When I read old legends of barn owls occasionally glowing red while hunting in twilight, I suspect it could be fluorescence rather than secondary bioluminescence...

Owls definitely glow under black lights I have carefully reviewed all the old reports on glowing owls, which are often said to be glowing "red" while hunting during twilight on dark moons. I am not persuaded by the hypothesis that they glow as a result of nesting in bioluminscent wood...

Please read this detailed description of a luminous bird encounter carefully. It shows ornithologist assumptions to explain the phenomenon. But it also gives a detailed account of the twilight conditions that I believe might be a "natural blue light" event in which both fluorescent and...

Earlier this year I saw what appeared to be a large glowing bird at twilight. The normal explanation for this is bioluminescent fungus contaminating a bird. I’m wondering if the effect might actually be a blue light effect where a fluorescent bird only appeared to glow because of the lighting...