The thing with gorillas is that the larger the troop the more engaging they are. Melbournes troop of 3 now 2, has lost most of the engagement a larger troop especially one with infants has. Even a bachelor troop with 5 or 6 males would be more eventful and engaging.
Hopefully we will see a new litter of snow leopards again sometime in the future. They are an importable species and there is a few holders still. So hopefully Melbourne will continue with this species.
Unfortunately there’s no demand in the region for Snow leopards at the moment; and due to the challenges in providing for their needs, new holders are unlikely to arise (with the alternative of Sri Lankan leopard proving more practical).
Billabong are reportedly hoping to continue with Snow leopard and planning to import. An alternative could be for them to receive Melbourne’s pair after they produce one more litter, with a cub staying on to breed with a new mate.