Besides our weekly “Ducks” and “Faux Ducks” features, I also have a backlog of bird photos by biologist John Avise. They are usually themed, and today’s theme is “Sky-gazing.” I’ve indented John’s notes and IDs.
First, the intro:
Sky-gazing
Have you ever wondered why birds so often appear to stare at the sky with one eye? What I’m talking about is illustrated in the photos below, which depict more than a dozen avian species caught in the act of what I’ll call “sky-gazing”. All of these pictures were taken near my home in Southern California, and the last one even shows a bird
sky-gazing while in flight.Why do birds so frequently sky-gaze?
Here are several (non-exclusive) possibilities. Birds might sky-gaze to:
(a) scan for aerial predators such as hawks;
(b) scan for edible prey such as flying insects;
(c) “check their watches” (i.e., monitor the time of day by noting the sun’s position in the sky, given their latitude);
(d) check for clouds or weather conditions;
(e) scan for conspecifics, or competitors;
(f) multiple or all of the above.Or maybe it’s none of the above. For example, perhaps these photos illustrate nothing more than happenstantial head movements caught on camera. Maybe some of the birds are just daydreaming. Or, perhaps some of these birds are actually staring at the ground or water from their other eye. Who knows? What do you think? [I suspect the correct answer is (f), but really my favorite hypothesis is (c)].
Whimbrel (Numerius phaeopus):
Hammonds Flycatcher (Empidonax hammondii):
Harlequin Duck (Histrionicus histrionicus):
Snowy Plover (Charadrius alexandrinus):
Least Sandpiper (Calidris minutilla):
Pied-billed Grebe (Podilymbus podiceps):
Cassin’s Kingbird (Tyrannus vociferans):
Mourning Dove (Zenaida macroura):
American Avocet (Recurvirostra americana):
Red-crowned Parrot (Amazona viridigenalis):
Willet (Catoptrophorus semipalmatus):
Ring-billed Gull (Larus delawarensis):
Pacific Slope Flycatcher (Empidonax difficilis):
Western Sandpiper (Calidris mauri):
White-throated Swift (Aeronautes saxatalis):
I have noticed birds at our feeders watching the sky while feeding. I’ve always assumed it was to keep watch for predators as our neighborhood is also home to many Cooper’s hawks (Accipiter cooperii). It is not unusual to find half eaten bird and small mammal carcasses around. Some are roadkill scavenged by black vultures (Coragyps atratus), which are also very common in my area.
I’ve noticed that too. In addition, our birds scan the ground for marauding neighbourhood cats!
I’ve noticed this behavior many times while filming birds. The life of a bird is pretty stressful.
Maybe they just think they look cool doing it. They do look pretty cool.
Maybe they are questioning why humans act so stupid.
Tell me some of those don’t say to you: “Trump? Really?”
You know crows are certainly saying it. Hahaha!
Nice!! They look so adorable!
Do birds in cages exhibit this behaviour?
I’m not sure that would be a good test of the ‘watching out for predator’ hypothesis, since the gesture may be instinctive.
What might be a better test is to see if apex birds of prey with hundreds of generations of evolution as apex predators still do it. If they do, then that might be evidence against ‘watching for predators’ being the main driving force behind the instinct.
I wasn’t thinking of any particular reason why they might do this, I just wondered if they lost the habit if they were in an enclosure.
Great photos – especially the last one.
It looks to me like it’s the -other- eye that is active, and they’re looking at something below them. Wouldn’t it be the same tilt of the head?
Exactly!
I love these fabulous photos! And I’ve always assumed it was to keep watch for predators, but now I really want to know 🙂
Nice photos.
I think I would assume mostly (a – predators) with an element of all of them.
I would suggest that (a) and (b) are partially testable, based on position in the food chain.
How do birds that are commonly preyed upon by other birds compare to birds that are not or to those that eat ground-level food?
Yes, and you might also note that three of the photos in my presentation are of flycatchers, who may well be scanning the sky for insects to eat.
…and, six of the photos are of shorebird species that are frequently preyed upon by Falcons.
Good pictures. I thought the link to Red-crowned parrot well worth reading.
Another possibility – again not mutually exclusive with the others on your list – is that birds in this posture may be turning their ear to the ground. For ground feeding birds such as some of the Turdidae, listening for movements of potential prey items either just beneath the soil surface or within the leaf litter may represent one way of detecting a meal.
That’s certainly another good hypothesis, especially germane for ground-feeding birds such as the American Robin (in the Turdidae)
Interesting ideas! And impressive photos.
Do birds with forward-placed eyes and binocular vision (owls, eagles, falcons) also do this? All of the example photos are of birds with laterally-placed eyes. Some of the hypotheses could apply to binocular vision, but not others.
That’s another very good point. I have no pictures of owls or diurnal raptors in this pose.
Loved the photos and the theme. It’s interesting that birds adapted to walking on the ground and those adapted to tree-perching display this trait. You’d think it would be more prevalent in birds that frequent the open ground, but apparently not. I like the comment above speculating about binocular vs. laterally placed eyes.
Thanks for these beautiful photos.
How do you know they’re looking up rather than looking down?
…wonderful!… in some way, one of my favourites of your submissions John!… kinda makes it ‘real’er in a wildlife sense…
…and heartily agree, f), then c)… you have a great sense of humour!…