While I was photographing the eclipse here in California (we only got a partial), a Cooper’s hawk landed on a tree branch above my head and stayed there the entire time, despite all the moving around I was doing. Usually they spook so easily, but this one just sat there, watching me as I went about my business for 2 hours. I’m not sure if this was eclipse related behavior or not.
Many have said that birdsong lessened during totality. Did you see/hear any changes?
I’m not sure if it’s related to the eclipse, but during the morning, there were plenty of songbirds flying around and being very active. At around 3:09, when the eclipse was by us, there were no songbirds at all. I only saw a vulture circling around in the distance. Later in the day, there were plenty of birds in another location. So maybe they were confused when the sky darkened.
I came out to Arkansas to visit family and right before totality the crows were chasing each other around and after totality all the song birds went off like it was morning all over again. Was pretty neat.
I saw a bat swoop down during the peak totality! It was freaky. It was squeaking and just kind of swooped down really quick. Other than that, nothing seemed that off. The birds were all quiet while it was dark but seemed to be totally normal once it was bright out again. Same with the squirrels.
While I was observing the Sun, it was really quiet. No songbirds chirping, unlike earlier. I also saw a vulture, which was pretty neat. Something I noticed was that no the squirrels in the area moved at all during the eclipse. They were all frozen for a few minutes, barely even moving an inch. After it was bright again, they just continued on with what they were doing. I found that interesting.
I tried to do a video to record the change in behavior of animals. I even rented a nice microphone for my camera. My camera stopped recording for some unknown reason. Didn’t get a record of all the birds stopping singing and then an owl hooting. It was wonderful to see and experience though. Took lots of photos of birds, butterflies, and flowers while we were there. We went to Richland Creek WMA near Corsicana, TX. Three hour drive to get there from my house. All on the back roads so no traffic. It was overcast with a sheet of clouds from the time we left until right before we got there, then it turned to partially cloudy. And luckily no clouds passed in front of the sun while it was in totality.
We also had a vulture come overhead, which is unusual, during eclipse though we only had about 90%. But I wonder if more vultures were just spotted because more folks were looking up and paying attention to the sky then?
I wish it were easier to make sense of all these anecdotes. IIRC, there HAVE been attempts to collect observations of animal behaviour during eclipses in the past. The problem, of course, being that strange behaviour will be massively over-reported.
Here’s a followup question I have – all these behaviours, are they typical stress responses, typical dawn/dusk activities, or maybe a truly unique behaviour? I can’t help but wonder if it’s not special to the eclipse per se.
I was next to a purple martin house while watching the eclipse. They all returned to roost and stopped singing during totality, and seemed to start their morning songs after it passed.
We also heard the crickets start up during totality. The whole experience was amazing.
During the totality I was in Watertown, NY which was on the path of complete totality. About half an hour before totality I noticed the birds calls starting to change and I noticed a spike in mosquito activity. During totality I noticed some different calls from the birds and a dog started loudly barking. After totality the birds were very loud and vocal, I also noticed the mosquito numbers went down to normal levels shortly after totality. I made four recordings of the birds and other animals before during and after totality posted here (excuse my aunts talking, she was in awe):
https://www.inaturalist.org/observations/206120732
https://www.inaturalist.org/observations/206122893
https://www.inaturalist.org/observations/206123722
https://www.inaturalist.org/observations/206125161
I went to a marsh in the Cuyahoga Valley National Park in Northeast Ohio.
I can understand being skeptical with anecdotal evidence from non-birders, but I would put more weight on those from birders, who are used to the patterns of nature and are more apt to pick up on abnormalities. It’s too bad these events don’t happen more often so that more data could be collected.
oh, simple! Let’s strap a rocket to the moon and alter its trajectory so we have a total eclipse a couple times per year! 
I can’t imagine any downsides or consequences!
We watched the eclipse on some bluffs in southern Illinois. There were a lot of turkey vultures and black vultures circling normally, following their own individual flight patterns, but as the light dimmed they definitely started flying as a flock, synchronized. These vultures roost communally, so I imagine they were exhibiting evening roosting behavior, but I didn’t see them land anywhere as totality approached - I was too busy staring at the sun.
PS the owl was a Barred Owl, which you can hear during the day time sometimes. So maybe it was calling all the while but I couldn’t hear it over the much closer/louder titmouses and gnatcatchers.
My behavior certainly changed! But yes the robins started acting very strangely in the area of totality and the crows were loudly cawing especially when totally started and ended. I was too enthralled with everything else happening in those 1.5 minutes to take iNat observations, but it was notable in many ways. Apparently mosquitos even came out in some areas, but in my location they haven’t come out yet. Others heard spring peepers singing where those are in the vernal pools.
Odd that so many people observed vultures. I wonder if there was a meteorological reason, for instance the eclipse probably strongly decreases thermals due to lack of solar heating, so maybe vultures that are usually higher up or elsewhere came down to roost due to lack of thermals. Or maybe it’s just a coincidence!
None whatsoever! When can we start? 
I’m unsure about whether this is a behavior change, but during totality, I saw a Canada goose fly in one direction, without honking. A minute after, when it was light again, I noticed two geese flying from the direction the original goose I saw flew. I have no idea if that was the same goose, or just a coincidence, but I thought it was interesting.
I noticed that the birds seem to be singing louder then usual.
These two statements are actually in agreement, though – if someone sees animals or birds continuing to behave normally, they are more apt not to bother mentioning it.