Construction workers laying the foundations for a new animal enclosures at the Portland Zoo (later Oregon Zoo) (negative 5 of 5).

A group of people stand in a pit at the construction site of the Oregon Zoo in Portland, Oregon. Some are first responders and others are construction workers. They all look to the left where rescue operations are underway. The caption on the negative sleeve reads, "Cave-in at new zoo site - rescue of two trapped workmen" (negative 2 of 12).

Two bear cubs at the Portland Zoo (later the Oregon Zoo). The cubs are seated by a door at the top of a concrete ramp (negative 5 of 5).

Jack Marks, Portland Zoo (later Oregon Zoo) director, with a six-month-old male ocelot cub that was recently added to the Portland Zoo (negative 8 of 11).

Construction workers laying the foundations for a new penguin house at the Portland Zoo (later Oregon Zoo). (negative 1 of 5).

Two men kneel in the penguin enclosure at the Oregon Zoo in Portland, Oregon. The man on the left holds his hand out to a group of approaching penguins. The man on the right smiles as a penguin stands in front of him. In the background, a small group of visitors watch the scene from above the enclosure. The caption on the negative sleeve reads, "Penguins checked by Alan Best, of the Vancouver B.C. zoo - and Jack Marks, Portland Zoo" (negative 1 of 8).

A group of penguins walk in an enclosure at the Oregon Zoo in Portland, Oregon. They walk away from a pool of water behind them. In the background, scattered visitors watch the scene from above the enclosure (negative 7 of 8).

A locomotive for the Zoo train being lifted by a crane onto tracks at the Portland Zoo (later Oregon Zoo). Four men are crouched at the base of the train guiding the locomotive into place.

A vulture is perched on a wooden beam in an enclosure at the Oregon Zoo in Portland, Oregon. The bird looks down at the camera below it (negative 1 of 2).

A polar bear stands up straight on its hind legs at the Oregon Zoo in Portland on January 2, 1959. The bear stands in an outdoor enclosure equipped with stairs and a pool. In 1959, this was the zoo's new location.

Rosie, an elephant at the Portland Zoo (later the Oregon Zoo) reaching her trunk through a fence to accept a treat being offered by a group of children from the Fruit and Flower Day Nursery (negative 4 of 6).