as a British-English speaking person, you would rhyme it with 'dark' and 'park', wouldn't you? (please say yes!)
to rhyme it with 'jerk' is the American way, isn't it?
Or has the pronunciation shifted? Just been watching 'The Promise' (Channel 4) where the British characters keep saying it the American way (and it is supposed to be in the 1940s as well!) and it is doing my head in!
DD's friend also recently told me her mother is a 'clerk' to rhyme with berk/jerk.