I wasn't aware of that. Oo.

central park makes up about 0.44% of all of new york city. in the webshow battle for dream island, its canonical from season one, episode one, that dream island is around a square mile, or 2.59km^2. thats roughly 75% of central park
tl;dr: a fictional island takes up less than one third of 1% of earth's 28th largest city population-wise