Smith and his colleagues are still studying the biological effects of these extreme pulses of food. They have already seen changes in the numbers and types of deep-sea animals living at Station M that appear to result from the feasts of 2011 and 2012. They will be reporting these findings in a subsequent paper.
The researchers note that deep-sea feasts may be increasing in frequency off the Central California coast, as well as at some other deep-sea study sites around the world. Over the last decade, the waters off Central California have seen stronger winds, which bring more nutrients, such as nitrate, to the ocean surface. These nutrients act like fertilizer, triggering blooms of algae, which, in turn, sometimes feed blooms of salps. The fallout from all of this increased productivity eventually ends up on the seafloor.
The authors also note that the changes in ocean conditions that provided more food for deep-sea animals at Station M might be related to global warming. Alternatively, these changes could simply reflect naturally occurring long-term cycles in the ocean.
These findings remind us once again that the deep sea is directly affected by events at the ocean's surface, as well as human activities on land. In fact, information from deep-sea studies such as this will be essential to improving computer models of global carbon cycling and climate change.
|Contact: Kim Fulton-Bennett|
Monterey Bay Aquarium Research Institute