Saint Louis Zoo
♂ Siegfried (death 1976-Dec-10)
♀ Florence (transfer 1975-Mar-04)
♀ Fattie (unknown ≥ 1971)
♀ Julie II (unknown ≥ 1971)
♀ Julie (death 1968-Dec-16)
♀ unknown (unknown ≥ 1968)
♂ unknown (unknown ≥ 1968)
﹖ unknown (unknown ≥ 1968)
♀ Anna (death 1967)
♂ Charlie (unknown ≥ 1966)
+ unknown individuals (see notes).
The Saint Louis Zoo no longer maintains a walrus exhibit, and to my knowledge there are no current plans to house them in the future.
Siegfried was initially imported from Zoo Hannover along with a female pup -- the female died in New York en route to the zoo.
Saint Louis imported "several" walruses to house with Siegfried, and all but one (Florence) had died by the early 1970s. I am not aware of how many animals were imported, although one source published in 1967 states that eight Pacific walruses had died at the facility, and an article published at the end of 1968 stated eleven had died in the last three years.