Was there a zoo in Hull?
Yes, that is the correct answer.
Hull Zoological Garden was the second zoo, in the UK, after London, to exhibit a hippopotamus. As previously mentioned, Hull's hippo is actually commemorated by a hippopotamus statue, situated near the site of the old zoo.
A little more information:-
In 1860 London Zoo acquired the hippotamus "Bucheet" which was shipped to London together with two shoebills; the shoebills were the first of their species at London Zoo and were, almost certainly, the first living shoebills ever to leave Africa.
London Zoo did not keep the hippo, presumably, because the collection already included a pair of hippos; the male "Obaysch" (received 1850) and the female "Adhela" (obtained 1854 ).
The hippo "Bucheet" was sold and then temporarily housed in Hull Zoo; the hippo was eventually shipped to North America.
I believe "Bucheet" was the first hippo to reach America; he subsequently died in a Canadian circus in 1867.