Pamela Forum Role: ParticipantActive Since: October 19, 2020Topics Started: 0Replies Created: 1 Profile Topics Started Replies Created Forum Replies Created Viewing 1 post (of 1 total) PamelaParticipant The length of time that the researchers studied the individual birds and got to know them, even without their tags. in reply to: Crow Research Techniques #937638 Viewing 1 post (of 1 total)