None.
? unknown (unknown ≥ 1981)
I have no information on how many walruses this facility has housed; footage of a walrus taken in 1973 and 1981 have been shared by the park, although I am not certain at this time whether these two sources show the same individual or not.
This facility no longer houses walruses, although in 2010 they expressed interest in constructing an exhibit for their zoo in the future. A conceptual layout for the park displayed in 2015 included space for a walrus exhibit within an "Arctica" area.