Chaser (April 28, 2004 – July 23, 2019) was a Border Collie with the largest tested memory of any non-human animal.

[5] She was taught by her owner, Wofford College Professor Emeritus of Psychology John W. Pilley, with the formal research published in Elsevier's journals Behavioural Processes and Learning and Motivation.

[4][5] Chaser could identify and retrieve 1,022 toys by name,[5] which was the result of a years-long research effort initiated by Pilley on June 28, 2004.

At this point, she became able to pair a novel object with a novel name in one trial, although rehearsal was necessary to log it into her long term memory.

[5][10] Chaser and Professor Pilley were featured in the documentary film, Seniors: A Dogumentary, from director Gorman Bechard.

Sharon Knolle in MoviePaws called it "a heartwarming celebration of these sweet animals and the people who make sure their last years are spent with a lot of love and comfort.