Aw c'mon. The babe poking a spear at the shark and the showdown of the tank and shark are pure homage to Harryhausen! (it sure reminded me of "Mysterious Island").
Of course the writer/director has some blockbusters under his belt... "Hollywood Chainsaw Hookers", "Evil Toons" (probably the real reason David Carradine hung himself) and "Attack of the 50-Foot Centerfolds", so how could anything go wrong? :lol