Thanks @Abbey! I hoped people would find it useful.
Auckland Zoo is a great zoo and has such a rich and fascinating history.
The Cotton-top tamarins were on Season 2 of The Zoo, which was filmed over 1999-2000. It was a brief segment which featured a keeper rounding them up at the end of day, chasing them along wooden beams. It was mentioned they’d probably headed down to Reptile Row, which was nearby.
Thanks, that's really interesting! The free-ranging animals would have been something of a marvellous sight.