Before the yolk sac completely disappears, the young fish must mature enough to be able to forage independently.Ichthyoplankton are planktonic, meaning they cannot swim effectively under their own power, but must drift with ocean currents.[10] Juvenile coastal fish are drawn to turbid shallow waters and to mangrove structures, where they have better protection from predators.[11][12] As the fish grow, their foraging ability increases and their vulnerability to predators decreases, and they tend to shift from mangroves to mudflats.[13] In the open sea juvenile species often aggregate around floating objects such as jellyfish and Sargassum seaweed.