I argue the Sacramento Zoo recently began it's golden age. Many species have left the zoo (hippos, tigers, lots of birds) but we've also been seeing lost of new species joining (aardvarks, meerkats, alligators, okapis, squirrel monkeys, and a lot of additions to the reptile house). Many animals are getting larger and improved exhibits (lions, otters, and giraffes). This golden age would of turned into a grand one if the zoo moving had been realized but I doubt that'll happen now. Still I'm sure the zoo will continue to improve on the land it's on. Don't get me wrong, I'm not arguing that the Sac Zoo's golden age is big as other, larger zoos', but for it's size, I think it's on the up-and-up.
Additionally, Sequoia Park, another small zoo appears to be soon entering a golden age with the realization of its master plan.