Confirmed that iNaturalist is totally fine with uploading older observations.
https://forum.inaturalist.org/t/can-i-upload-older-photos-as-observations/3259/3
Tried out the Flickr importer. It's a bit rough for selecting, but it imports the description, time & location along with the photo, and you can import batches at a time.
I don't want to totally flood my profile, but I've got a lot of timestamped photos of animals & plants since I bought my first digital camera...
Uploaded a handful of #bird #photos ranging 2004-2015.
I imagine this #seagull reading the "No fishing" sign and being very disappointed.
An #egret wading in a marsh.
And another egret (I thought it was a crane at the time, but 3 people have IDed it as an egret) that I caught walking by the side of the road.
Funny thing is: I didn't use the Flickr-to-#iNaturalist importer for these. On Flickr I posted the full, composed shots. For iNat, I wanted to crop them to show the birds more clearly.
@kelsonv first one is just fantastic
@maow Thanks!