What can I do about this strawberry thief (detail inside)

My mom has a big garden in the balcony of our top floor. She plants various kinds of plants there, from flowers to edibles. Among them are two pots of strawberry trees, one on the ground and the other on a shelf.

So the strawberries became ripe recently. Yesterday afternoon my mom came upstairs to harvest the strawberries. That was when she realized some animal had eaten the riped strawberries. The strawberries were not eaten whole but were partly bitten. Another rather gross clue that the thief left behind was two big pieces of poop on the floor and on a leaf of another plant. Nothing else was disturbed. Last night when we were asleep the thief came back to finish the job and ate the last strawberry in the exact same manner. This time it didn’t leave any poop behind, and still nothing was disturbed.

I’m thinking it was a rat because of the way the strawberries were eaten. But then the poop was big and solid. It must have been a really giant rat to make that kind of poop. And why did nothing else apart from the strawberries was disturbed? One pot of strawberry tree was on a rather high self, and for a rat to get there it would have at least made some visible disturbance to other plants. And also there was a large cucumber next to the strawberries. It wasn’t touched one bit.

We aren’t sure what to do because we don’t even know what kind of animal we are dealing with in the first place. Right now the best thing we can do is to cover up the strawberries and put out mouse traps. But do you have any more suggestion?