Baby blackbird

I found a baby blackbird and my cats were just about to get it. It's in my greenhouse,  safe from the cats.

It's chirping but nothing is calling back. I assume the cats have had the parents.

What can I do for it. It has a few strawberries and nuts for it to eat. I don't know if that's any good.

We can't take it to a wildlife place until tomorrow. Will it be okay?