OAKLAND -- After years of quarrels with neighbors, red tape and legal struggles, the Oakland Zoo is set to get bigger and better, zoo officials say, with the addition of California native animals and even an aerial gondola.

A judge in Alameda County Superior Court last week ruled against environmental groups seeking to stop the zoo's plans to expand about 54 acres into undeveloped Knowland Park to build a veterinary hospital, gondola, new animal exhibit, camping area and an educational-interpretive center.

"(It's) a good day for hundreds of thousands of zoo visitors, school children and our animals,'' said Nik Dehejia, zoo project director. "We are thrilled that the court has acknowledged the zoo's project as environmentally sound, upholding the unanimous approval of the plan by the Oakland City Council last June."

The Friends of Knowland Park and the East Bay Chapter of the California Native Plant Society filed suit last year following the City Council's approval of the project. They argued plans had changed dramatically and there would be increased impacts on rare plants and threatened species, such as mountain lions, bobcats, foxes, coyotes, deer, hawks, owls and the threatened Alameda whipsnake.

They also argued the approval violated state law and several Oakland general plan policies. They wanted the zoo to complete a full environmental impact report to document what, if any, impacts there would be on Knowland Park's wildlife habitat and rare native plants. An attorney for the environmental groups said they are considering an appeal.

Zoo officials say they completed the required environmental review process and the Oakland Parks and Recreation Advisory Commission, Planning Commission and City Council approved the project after lengthy open discussions and community meetings.

"We are very disappointed in this decision," said Ruth Malone of Friends of Knowland Park. "In making this decision to vastly expand its development, the zoo, unfortunately, is not prepared to walk its own conservation talk here at home."

Zoo officials see it differently.

"The zoo's expansion plans represent our commitment to improving and protecting the unique biodiversity of the 490-acre site through a comprehensive habitat enhancement plan,'' Dehejia said, adding that plans call for the control and eradication of invasive plant species and the revegetation of native grassland and other native plants.

Opponents said if the decision stands, it sends a message to developers that they can propose a modest project and gain approval under a lower level of environmental review then make changes in subsequent versions while still claiming it does not require a full environmental review.

"We obviously disagree with the court's findings. The real pity here is that the public will be stuck with an environmentally damaging project because the decision prevents an analysis of alternatives," said Laura Baker of the Native Plant Society.

Construction is already under way for a new 17,000-square-foot veterinary hospital that will allow veterinarians to better care for sick and aging animals, who live significantly longer in the zoo than they might in the wild.

Follow Kristin J. Bender on Twitter at Twitter.com/kjbender.