 In 1987, a new master plan was formulated to dramatically expand the zoo.Over time, many new exhibits were built, including a new sea lion exhibit (1987), a humboldt penguin exhibit (1988), "Plains of Africa" (1991–93), "Madagascar" (1995), and "Marco Polo Trail" (1996).In 1989, the old Menagerie building was once again renovated, this time into a new gift shop.