"Marwood Zoo" was so named because of the lead actor's middle name: John Marwood Cleese.

The actress Maria Aitken, who appears as Di Harding in Fierce Creatures, also appeared as Wendy Leach (the wife of John Cleese's character) in A Fish Called Wanda

Some quotes featured in the film have been lifted from the Monty Python repertoire, such as "Beautiful plumage" (from the famous dead parrot sketch, here referring to the keepers' new costumes) and "It's only a flesh wound" (as the Dark Knight's cry from The Holy Grail is given to Pip when she pretends to be wounded)

In the final scene of the film, Rollo accidentally calls Willa "Wanda", a reference to the name of Jamie Lee Curtis's character in the earlier film "A Fish Called Wanda"

Bugsy's pet tarantula, Terry, was in fact named in honour of Terry Jones, with whom Michael Palin once wrote a sketch entitled "The Fierce Creatures Policy", upon which this film was based.

John Cleese's character, Rollo Lee, shares his name with a lemur. Similarly, in A Fish Called Wanda, Jamie Lee Curtis's character has the same name as the eponymous fish: Wanda.