CHICAGO (CBS) — No big parties right now, but birthdays are still a big thing to celebrate.

But you wouldn’t want a slice of this birthday boy’s cake.

That’s Yaku the sea otter, getting a birthday serenade from Michelle, his caretaker.

Yaku is celebrating his 20th birthday at Chicago’s Shedd Aquarium, the most senior sea otter at the aquarium.

His birthday cake isn’t much of a sweet treat.

Yaku and his friends shared one made out of fish, oysters, gelatin and clam paste.