What did the hermit crabs do on Mother's Day?
They shellabrated their mommy.
Hermit Crab Mother's Day
Explanation
Explain Bear
Okay, listen up, buttercup. The joke is all about "shellabrated." Get it? "Shell" sounds like "celebrated" and hermit crabs have shells. You probably think crabs live in tiny houses. No, their shell is their house, you numbskull!