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Oceanic Zone

Oceanic Zone

The open ocean waters beyond the continental shelf - vast, low-productivity blue water hosting migratory pelagic species.

Depth: 0-200m Light: Sunlight Temp: 5-30

📖 Overview

The oceanic zone is what you see from a boat 100 miles offshore - blue water in every direction. Less productive than neritic waters (fewer nutrients), it hosts the migratory highway of the seas: tuna, billfish, sharks, whales, sea turtles. Fisheries here are concentrated at seamounts, thermal fronts, and floating debris that create localised productivity.

🌿 Ecology

Low but consistent primary productivity. Pelagic food web: phytoplankton to zooplankton to forage fish (flying fish, saury) to apex predators (tuna, marlin, sharks).

⚠️ Threats

Overfishing of migratory pelagics, plastic gyres, warming waters, deep-sea mining.