According to Robert Hrouda, ArenaNet’s Content Designer, the Meta Event Karka Queen is not yet active on the island, until next week:
Yes. The Meta event and Karka Queen world boss will be a permanent event added to Southsun, and it’s drop will be permanent as well.
One of the core problems of the island was the lack of events. I’;d hoped to solve that by adding an island wide Meta event and a world boss.
However it is NOT out until next week. We’re actively working on modifying our patch notes.
We’re having a small issue with our patch notes we are attempting to resolve currently. The Meta Event is not yet active on the island.
Spotted on GW2 forums