I was walking by a lake the other day...

...when I saw a heron. I was so busy watching him, I tripped over a rock, and I swore that the heron was laughing at me.

"Laugh all you want," I said, "I am part of a species that has the power to make you all extinct. What do you say to that?"

The heron replied, "Dijeron!"

In case you don't get it, it's a triple multilingual pun. See, dijeron is a past tense "we" or "they" form conjugation (although only the "we" form is considered in this joke) of the Spanish word "decir", meaning "to say". The "j" is pronounced like the English "h". So the heron says "dijeron", which sounds like "the heron", which is a pun in English because he's a heron. It's also a pun in Spanish because the heron's pretty much saying "We said!", which is kind of like "Say!", in reply to my "what do you say to that?", so it's also a pun in Spanish. Also, it's a pun in French since "to say" sounds a bit like "touche", a French word, which pretty much translates to "good comeback" or "good point". So the heron's acknowledging that my being able to exterminate his species was a pretty good point, and that it shouldn't be laughing at me. So in conclusion, it's a pun in:

English
Spanish
and French.

Yeah. I came up with this at two a.m. last night.