If you've seen this photo before, be warned: You may have been told a lie.
The photo shows a scene on the ocean where the waters of the Mississippi River meet the waters of the Gulf of Mexico. It is frequently shared with a caption like, "The two bodies of water never mix with each other, allowing the Gulf of Mexico to retain its clear, blue color. Simply amazing!"
However, that's simply not true.
The photo actually depicts a dead zone, a phenomenon that is not some miracle of nature, but, in fact, quite the opposite — it's manmade.
The dead zone is created by the Mississippi River, but not simply from the river's water. Instead, the dead zone is caused agricultural runoff and treated sewage from cities along the river, which pour into the river's waters and choke it with nitrogen and phosphorus. The nitrogen and phosphorus cause enormous phytoplankton blooms, which result in larger zooplankton populations that feed on the phytoplankton.
Then, according to Snopes, "Large amounts of dead phytoplankton and zooplankton waste then accumulate on the bottom of the seabed. The decomposition of this matter depletes the oxygen in the area faster than it can be replaced." That makes it nearly impossible for life to survive in the water.
Unfortunately, despite what it looks like in the image above, the waters actually do mix with those of the Gulf of Mexico, and, as a result, many fish there are killed. Worse yet, human activity causes similar occurrences in bodies of water around the world.
The image is a striking one, but not because it's a powerful example of nature's beauty. Instead, it's a strong reminder of what a toll pollution can have on the natural world.
Learn about how you can help vulnerable marine animals by signing up with Oceana.