The origins of the zoo lie with the story of Franz and Louise Zinner who moved to Lebanon, PA from Weisenberg, Germany in 1899.  The Zinners had owned twelve prairie dogs and a bear cub, however they were unable to keep them in their yard in Lebanon.  They also knew that Milton Hershey was in the early stages of building a park and in 1905 they went to see Hershey to speak to him about keeping the animals as a park attraction.  Hershey agreed and after a lengthy discussion the two men decided to build a zoo.  Franz Zinner served as the zookeeper until his death during the 1918 Flu Epidemic.

During Milton Hershey’s lifetime Hershey Zoo was a local attraction.  In the era before television, zoos played an important role educating the public about animals and environments different than central Pennsylvania.

The earliest animals acquired for the Hershey Zoo came through donations and personal relationships.  William “Lebbie” Lebkicher seemed to have been particularly interested in the zoo and was often mentioned in conjunction with acquiring new animals for the zoo.  The animals ranged from the mundane to the exotic. In 1910 the zoo acquired two black bears, a pair of Zebus, a family of ‘possums, deer, angora goats, pheasants, three peacocks, and fox squirrels.

From the beginning of the zoo, monkeys were a popular attraction.  There were a wide variety of primates, including rhesus monkeys, wooly monkeys, spider monkeys, and golden baboons.  Also, The zoo was fairly successful in breeding animals and there were frequent mentions of births of birds, goats, and deer.  When the animals died they were often stuffed and mounted for display.

In 1914, with the addition of the first lion, the Hershey Zoo had grown so much that it was being described as the Hershey Zoological Garden.  In 1915, Hershey proclaimed itself the “largest free private zoo in Pennsylvania” and in 1916, the zoo was entirely remodeled and a large central building was added.  The next major change to the zoo did not take place until the 1930s.  The 1930s were a period of growth and expansion for the Hershey Zoo.  By the end of the decade the zoo covered forty acres and contained individual houses for primates, carnivores, small mammals, antelopes, tropical birds, pheasants, and fish as well as outdoor cages and enclosures.

In 1934 the zoo added a Bird House, a Reptile House, and a pair of baby elephants.  However, Milton Hershey felt people were more interested in monkeys than the elephants, and as a result the elephants were sold.  However, the zoo's orangutans, Jiggs and Maggie, were a particularly popular attraction.

By the 1940s, more than 300,000 people visited the zoo each year.  In 1941 the zoo set single day attendance records with 13,289 visitors.  An earlier record of 12,004 people had stood since 1936.  At some times during its history the zoo charged an admission fee, approximately ten cents.

With the advent of World War II, Hershey Zoo closed on December 20, 1942 for the duration of the war.  Several factors contributed to the decision to close the zoo, mainly because the zoo staff of 30 keepers had shrunk to only 2 employees with the rest either entering military service or transferring to production employment.  Without proper staffing the zoo was unable to properly care for all the animals.  The zoo remained closed until May 7, 1950, when zoo director, Clarence Moose celebrated its grand reopening with a new monkey exhibit, which was installed in the old bird hall.

The zoo remained open for 20 years until a decision was made to close it due to plans for the new HERSHEYPARK.  The zoo closed in 1971 when HERSHEYPARK moved to a one-price admission format as part of its restructuring into a themed amusement park.   Plans for the new park included the development of an Animal Garden.  The old zoo was used to house the animals when they were not on exhibit in the Animal Garden.

In 1975 John Strawbridge was serving as a director for the Hershey Museum, and convinced Hershey Estates to invest in redeveloping the old zoo as a themed zoological park: ZOOAMERICA.  By building a bridge across Park Boulevard, HERSHEYPARK was able to directly link the zoo to the park.  Opening in 1978, ZOOAMERICA featured exhibits of animals native to North America, with naturalized animal habitats.  In 1982 ZOOAMERICA became one of only 50 zoos in the United States (and only two in Pennsylvania - Philadelphia and Hershey) to receive accreditation by the American Zoo and Aquarium Association.

The educational focus of ZOOAMERICA is an important asset for HERSHEYPARK.  The zoo provides the park with opportunities to tap into school groups and field trips.  These marketing efforts are often coordinated with HERSHEY'S CHOCOLATE WORLD and Hershey Museum to create a daylong experience for students.  A visit to HERSHEYPARK is included as a fun activity after the educational activities are completed.

Over the years ZOOAMERICA has often featured special temporary animal exhibits to attract new and returning audiences. In 2000 ZOOAMERICA opened a major new exhibit for bears.  The bear habitat was moved and completely revamped, giving the animals a natural environment in which to roam.  In addition, the "Black Bear Encounter" features a 13,000-gallon swimming pond for the bears.  In 2001 the Zoo brought in a temporary exhibit of two albino alligators.

Throughout its history, the zoo staff has a history of being involved with wildlife conservation projects, including the breeding of a variety of endangered species (birds of prey, reptiles).  ZOOAMERICA continues to succeed in honoring its obligation to protect its occupants while educating the public about them.