The neritic mesopelagic zone biome comprises the marine column that occurs above a continental shelf and extends from approximately 200 to 1000 m depth - the maximal depth of light penetration in all but the clearest oligotrophic ocean regions. In comparison to the epipelagic zone, dominant forms of pelagic organisms do not change very much; however, there are marked changes in species composition and the proportion of smaller-sized individuals decreases.