Work has started on an expansion of San Diego Zoo's "Journey into Africa" attraction, which is due to be completed in time for the summer season.

Located in the zoo's Wild Animal Park, the designs are still being finalised for the new areas, which the North County Times estimates could cost US$4m.

As it stands, the "Journey into Africa" tour already boasts rhinos, giraffes, Cape buffalo, ostriches, zebras, hornbills, wild swine and antelope.

The expansion comprises a lakefront flamingo habitat, marshland with a waterfall, wooded grassland, scrub for scavengers, a hillside for the park's Somali wild asses, a rock habitat for klipspringer antelope and a savanna for the zebras.

According to the newspaper, park officials hope the new exhibits will bring in more visitors and help it offset a combined loss of US$21.6 million in 2008 for the park and San Diego Zoo, both of which are operated by the Zoological Society of San Diego.