"The Bear Whose Poo Turned Black" by Peter B. Smith
Life on a Quadra Island, BC vineyard was turned upside down one autumn almost at harvest time when a black bear broke into the property and feasted on the grapes on 19 consecutive nights despite all the efforts of staff, backed up by conservation officers, to keep him out or to capture him. That's the basis for this true-life children's book where the adventures of bear and staff are related, mostly from the perspective of the bear himself.
Of greatest interest to most children would be how the staff could study the contents of the piles of poo left in the vineyard to determine upon which grapes the bear was feasting, culminating in the day when everything changed colour!
The funnier moments sparked the ideas for the black-and-white cartoons which illustrate the book.
The author was as close as anyone to the action when, as one of the staff, he was tasked with repairing the damage caused by the bear's repeated nocturnal visits.