Fecal pellets, sinking rate

In addition to undigested organic matter, fecal pellets also contain fragments of calcareous and siliceous hard parts and clay-sized grains of clay minerals. Fecal pellets can harbor viable bacterial and phytoplankton cells. Because of their fast sinking rates, fecal pellets reach the seafloor relatively intact. Their organic matter represents the major source of food for the benthos. 

Smayda, T.J., 1969. Some measurements of the sinking rate of fecal pellets. Limnol. Oceanogr., 14 621—625. 

Though quantitatively of less importance than fecal pellets, the exuviae (cast exoskeletons) of crustaceans represent another form of particle production (60) these have sinking rates on the same order of magnitude as fecal pellets, and transport radioisotopes as well (46, 47, 61). The abandoned houses of larvaceans (62) and gelatinous pseudo-conchs of pteropods (4), together with entrapped particles, form mucoid aggregates that develop microbial microcosms of their own. 

Fowler, S. W. Small, L. F. Sinking Rates of Euphausiid Fecal Pellets, ... 

Turner, J. T. Sinking Rates of Fecal Pellets from the Marine Copepod... 

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