Scaphopod Diet

Most literature reports indicate that scaphopods are predatory on foraminiferans, and that appears to be generally the case (Bilyard, 1974, Poon, 1987, Shimek, 1988, Shimek 1989, Shimek, 1990, Shimek, 1997). However, a few species buck the trend and are definitely NOT specialist predators on forams; the best example of that is Rhabdus rectius (Carpenter, 1864) from the N. E. Pacific, (See Below). Although found in many habitats from Alaska through northern California, this species is typically most abundant in very silty sediments and is often present in quite high densities, sometimes exceeding 50 animals/m 2 (Shimek, 1990). In these areas, it appears to eat just about any food it can catch, and it may be a "keystone predator"  significantly influencing the abundances of the potential prey species in the sediments.

The figure below gives dietary information for several scaphopod species. Note that Rhabdus rectius has a distinctly different diet when compared to the other scaphopods.

The link above will take you to tabular data of Rhabdus rectius and Gadila aberrans , two scaphopod species found commonly in fjords of the Vancouver Island coast.   These data clearly show the diversity of items in the Rhabdus rectius generalized diet compared to Gadila aberrans , a specialist predator on foraminiferans.

Ron Shimek