A trip to move three elephants from the Toronto Zoo to a Performing Animal Welfare Society sanctuary in Northern California has been delayed because of extreme heat expected in Canada in early August.

PAWS co-founder Pat Derby says moving elephants is risky enough without adding unpredictable obstacles.

To protect the elephants, Derby says the society and the city of Toronto decided to postpone the trip.

When it occurs, the trip will start with a one-hour truck ride from the zoo to the airport, where the elephants will be put on a Russian cargo jet and flown to San Francisco. Trucks will then take the elephants to their retirement home in San Andreas.

Derby says they hope to make the move by the end of September.