seen jelly fish & crab

this is what i saw at the ALBERT DOCK's river stream. u see that, don't u? upper 1 is a crab while the lower 1 is jelly fish, i am actually highlighted the obvious 1. the rest are jelly fish as well, just from top view. i saw millions of jeely fish. it got my nerve, as you can imagine, out of sudden, u drop into the river, do u think u gonna survive. on top of that, the meter shown the river has near to 6 metres high. dare u jump down & swim?