due to thread drift, I offer this:
https://www.seattlemet.com/news-and-city-life/2017/05/the-secret-life-of-urban-crows
her doctoral advisor was a grad. student of Russ Balda (who got nabbed by FWS for lack of a federal permit to - guess what? - "take" jays during his studies)
Balda was at No. Az. univ. and his lab may still have a web page - he worked out all the spatial memory on jay's stuff (and yes they are exceptional at locating where they buried nuts/acorns; also at robbing squirrels which they watch bury them)