May Provide a Negative Climate Feedback Recent reports from marine biologists discussed in Scientific American , December 1995, pp. 28-29, suggest that tiny, gelatinous, tubelike animals called salps may be responsible for a portion of the missing carbon sink . The Southern Ocean's temperature has increased an average of 2 to 2.5 degrees C during the last 40 years, and salps, which thrive in warmer waters, have blossomed, replacing krill as the dominant form of zooplankton in the area. There was a fourfold increase in salp biomass between 1980 and 1990, according to data from Soviet researchers, and the salps have continued to spread much further south than before.
Salps are important for what they eat and excrete.
At night, salps return to the depths as much as a kilometer below and there they dump carbon-rich fecal pellets that sink as fast as 2.7 kilometers per day. Once buried in sea sediments, the carbon is out of the system for thousands of years. Reality may be a good deal more complicated than this, however, the researchers say. For one thing, there may not be enough salps to make much of difference in terms of large scale climatic effects. For another, too much of a good thing can be lethal to salps.