Shifting marine animals: Depth vs. latitude
By Rachel Berman
A diver experiences a unique vertical habitat in the Pacific. Credit: Twilight Zone Expedition Team 2007, NOAA-OE
How about depth/elevation? Climb up a mountain and you might find yourself more exposed to the rays from the sun, surrounded by thinner, colder air, and it might be a little breezier the higher you go. In the ocean, the changes that occur with depth are related, but a bit different. There are about 5000 meters (16,400 feet) between the “sunlight zone” and the “abyss.”
The layers of the ocean have different properties, and they each host a different set of characteristic inhabitants. The photic (epipelagic) zone is the top layer of the ocean where light from the sun supports the growth of phytoplankton and algae. These phytoplankton then support a wide range of fish and invertebrates, especially on the relatively shallow continental shelves that surround each continent. Overall, species tracked on the OceanAdapt size have moved an average of almost 10 meters deeper over the last three decades. While not dramatically deeper, it suggests that many species are moving offshore in search of cooler waters.
Read about shifting marine species: