Do squirrels ever lose their nuts?

We put Vinnie's question to zoologist Max Gray... Max - Yes is the short answer, but not as much as people seem to think they do. It's quite a common mistruth that squirrels forget about 50 per cent of their nuts which is not quite how it works. Squirrels are actually very good at remembering where they've left their nuts.

Kat - How do they remember? Do they mark it out?

Max - They remember. Exactly the mechanisms involved in this has been studied in a lot more detail in birds, in a bird called the Florida scrub jay by somebody called Nicky Clayton here in Cambridge actually. They used a combination of both relative and non-relative directions and cues and landmarks, and that kind of thing. But we also believe that squirrels use their sense of smell to assist them. They may be able to smell because they don't bury their nuts very deep as they may still be able to smell the acorns. But they inevitably don't retrieve some of them. But the important point is that if they don't retrieve the nut, that's not necessarily because they've forgotten where it is.

Kat - They're saving it for later.

Max - Well, you would imagine a squirrel going about preparing for winter is frantically running around in oak forests, stealing all the acorns and burying them all over the place. But you're going to prepare as a squirrel, you're going to want to prepare for an unusually long winter or a winter that starts earlier or in case some of your acorns get dug up by other squirrels which happens.

Kat - They get nicked. Do they nick each other's acorns?

Max - Yes. Actually, there's some evidence that squirrels will fake-hide their acorns. They'll kind of scurry about in the Earth and not put an acorn there if there's other squirrels watching them.

Kat - They're like.ooh!

Max - Yeah. It's called tactical deception which is quite a fun term.