Big Animals Make Small Animals More Abundant

cage.jpg

ResearchBlogging.orgI’ve already addressed the difficulty of doing experiments in the deep sea which ultimately leads to their rarity. I also mentioned given the costs and risks of doing something so crazy like an experiment in the deep sea makes funding scarce for such projects. I’m not bitter at all that NSF reviewers chose not to fund me twice….no not at all…I won’t even mention it. Moving on!

Luckily scientists like David Thistle value such an approach and find creative ways to fund and carry out such a project. Thistle et al. report on a similar study to the Gallucci et al. study we reported on recently. Gallucci et al. focus on the impacts of megafauna (those large organisms easily seen in video and collected in trawls) on nematodes. Thistle et al. focus on large, mobile epifaunal (LME, e.g. sea cucumbers, seastars, and demersal fish) effects on polychaetes, kinorhynchs, nematodes, and copepods. Five cages were deployed in the San Diego Trough to exclude LME from certain areas. In general, the abundances of the groups were lower in the cages than in the background.

This implies that LME actually increases abundance in those tiny, little, organisms that live in the beautiful soft mud.

THISTLE, D., ECKMAN, J., PATERSON, G. (2008). Large, motile epifauna interact strongly with harpacticoid copepods and polychaetes at a bathyal site. Deep Sea Research Part I: Oceanographic Research Papers, 55(3), 324-331. DOI: 10.1016/j.dsr.2007.11.008