I personally would prefer Platypus Day. There’s an animal that deserves to be celebrated. It’s a furry, poisonous rat‐duck. A platypus is practically a living Pokémon.
But somehow the groundhogs won out. I suspect bribery.
For the record, today I will honor platypi in my heart. Although Wikipedia tells me that platypi is incorrect and I should say platypuses or platypodes. Also, they are venomous and not poisonous (venom is injected, poison is consumed).
To which I say: poisonous rat‐duck sounds better than venomous rat‐duck, and platypi has a satisfying faux‐intellectual ring to it. Let rhetoric prevail, and let the poisonous rat‐ducks have their day on the calendar!