El Niño and its effect on marine animals is in how it changes surface water and pushes the mixed layer deeper. The warm phase of an ocean cycle (opposite of La Niña) that periodically sees warmer, nutrient-poor water flow west across the Pacific and reverses wind patterns leading to drought in Australasia. El Niño has a significant affect on marine animals and the way they feed.
Warmer surface water pushes the nutrient-filled mixed layer deeper, meaning sharks and their prey, swim closer to the coast, where upwellings physically push the nutrients to the surface. Predators do well and prey are concentrated in hotspots.
