[Jed Eckert]

They're just returning home:

"The capybara that are being seen today are most likely the descendents of escaped captives, but people still find fossilized capybara teeth and bones from Florida’s original capybara in the Santa Fe, Suwannee, St Marks and St Mary’s Rivers in North Florida. You may also find capybara fossils in springs and spring runs like the Ichneetucknee River."
--Wild_Capybara_return_to_Florida-

Now, my questions are, what is a good caliber and load to use? What will be the bag limit? :)

[Afterguard]

“Now, my questions are, what is a good caliber and load to use? What will be the bag limit? :) “

FWC says .22 rimfire and single shot .410 only. Year round (no season). Bag limit not specified.

[NorthMountain]

Now, my questions are, what is a good caliber and load to use?

.223 Rem, 55gr V-Max?

[TxAg1981]

Non-game animal...therefore no bag limit, no possession limit. The only limits are dictated by the amount of ammo you have.
I'm not a Florida resident but that is how non-game species are handled in other areas.
I bed they would be fun to bust with 22hornet.
I bet they taste like chicken too!