Dallying with the Divines

So, this was a long time back - I've written far too much and filmed far too much, so basically here's some out of date images and videos and at the end some out of date thoughts subsequent to the out of date media. OK? [Not really... - Ed.]

I am assuming this is Divo rather than Diva, but whichever, I love how the feathers cover the feet like a cozy duvet. I like to imagine having UV vision... what would the crow look like if I could see the colours that I am sure are there, invisible to me, in the plumage? Some birds which look sexually monomorphic to our eyes are completely different for UVS creatures. So, is that the case with crows?

Seems not, thanks to the Corvid Research blog for this:

While it’s true that most passerines are what we call UVS birds, corvids, like flycatchers and most raptors, are VS birds, meaning their visual system is biased toward the violet-spectrum and they are not considered especially sensitive to UV light.3,5 The low UV-detection abilities of corvids and many raptors, appears to offer a lifeline to smaller passerines, which exploit these visual differences in their plumage, allowing them to remain conspicuous to potential mates, while staying inconspicuous to their potential predators.6 Given this finding, we would expect crows not to, for example, show a great deal of UV detail in their feathers, and the research seems to bear this out. A study of large-billed crows found them to be so weakly iridescent, that the authors proposed their violet-blues hues may simply be an artifact of chance, and play no functional role.   Likewise, unlike many other passerines, crows don’t seem to communicate aspects of their identify via secret codes in their feathers. A 2007 study, for example, confirmed that American crows, fish crows, and Chihuahuan ravens are sexually monochromatic from an avian visual perspective, meaning there’s no UV signaling of “male” or “female” hidden from us in their feathers.8 These birds were among only 14, of the 166 North American passerines sampled, for which this was true.

Despite these findings though, the role of UV in the lives of crows and other corvids hasn’t been rendered completely immaterial. When presented against high contrast backdrops (green foliage), fish crows are more adept at picking out UV reflecting berries than matte black Vaccinum berries. On the other hand, when both are presented in front of a backdrop that offers no contrasting advantage to the UV reflecting fruit (sandy backdrops) they pick out both berries equally.9 And while the UV spectrum may not be super useful to crows for coding information, that doesn’t mean the feathers of corvids don’t carry any weight. Common magpies, for example, convey all sorts of information from sex to age to territory status in their iridescent tail feathers.10 Taken together, these findings seems to suggest that there is a lot more to unpack with respect to the role of UV in the lives of corvids than, well, meets the eye, and species-specific studies may be necessary to fully parse the potential nuance.

Anyway, he's still handsome. Or she.

This is Divo again, having a scratch. The picture isn't great because of the light [Not the camera operator? - Ed.], but I like how he seems to use his wings as supports to help him balance while his right foot is at his head.

When I was on the way out of the part, the Driveways had gone, but this little person was there.

I wondered if this was the same lactating female I'd seen in my garden?

Finally, the video of the park visit.