Western scrub-jays hide food, such as acorns, to eat later – called ‘caching’. Previously scientists have thought that the jays did this only on instinct and that there wasn’t much planning involved.
Scientists had thought that only humans can plan for their future needs in a detailed way, but research seems to show that some birds can also think about storing food for the future.
In one experiment, each bird was kept in a cage which could be divided up. To start with, the birds were given only powdered food, which they couldn’t cache. Then in the morning, they were confined either to an area of the cage where they were not given breakfast – the ‘no breakfast’ area; or in an area where they were given something to eat – the ‘breakfast’ area.
Given the first chance to cache whole pine nuts in the ‘no breakfast’ and ‘breakfast’ areas of the cage, the jays cached three times more pine nuts in the ‘no breakfast’ area than in the ‘breakfast’ area.
Jays can make future plans
This seems to show that they understood there might be no food given to them the following morning and so they tried to ensure they’d have something to eat.
Jays choose a varied diet
In a second experiment, the birds were initially fed only powdered dog biscuits for breakfast in one area, and powdered peanuts in another. After a few days, the jays were given whole peanuts and whole dog biscuits in the evening, with the chance to cache them in the ‘breakfast’ areas.
The jays took this first chance to cache both types of food in each breakfast area, putting peanuts as well as dog biscuits in the area where they were usually only given dog biscuits, and vice versa. This may indicate that not only can the jays plan for the future, they also need variety.
Professor Nicky Clayton said, “The western scrub-jays demonstrate behaviour that shows they are concerned both about guarding against food shortages and maximising the variety of their diets in the future. It suggests they have advanced and complex thought processes as they have a sophisticated concept of past, present and future, and factor this into their planning.”
Earlier experiments had showed that scrub-jays could remember when and where they saved food, and which type of food they had saved. This is called ‘episodic-like’ memory, and was also previously thought to exist only in humans.
Jays are members of the crow family. People through history have considered that crows are intelligent, and these findings appear to back that up.
The Cornell Lab of Ornithology also tells us this interesting research snippet about jays’ abilities: “Jays that had stolen the caches of other jays noticed if other jays were watching them hide food. If they had been observed, they would dig up and hide their food again. Jays that had never stolen food did not pay any attention to whether other jays were watching them hide their food.”
The natural habitat of western scrub-jays is the west of the USA in areas of stunted trees – known as ’scrub’ – and they also now live near surburban areas.
