Big Animals Make Small Animals More Abundant


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

Dr. M (1801 Posts)

Craig McClain is the Executive Director of the Lousiana University Marine Consortium. He has conducted deep-sea research for 20 years and published over 50 papers in the area. He has participated in and led dozens of oceanographic expeditions taken him to the Antarctic and the most remote regions of the Pacific and Atlantic. Craig’s research focuses on how energy drives the biology of marine invertebrates from individuals to ecosystems, specifically, seeking to uncover how organisms are adapted to different levels of carbon availability, i.e. food, and how this determines the kinds and number of species in different parts of the oceans. Additionally, Craig is obsessed with the size of things. Sometimes this translated into actually scientific research. Craig’s research has been featured on National Public Radio, Discovery Channel, Fox News, National Geographic and ABC News. In addition to his scientific research, Craig also advocates the need for scientists to connect with the public and is the founder and chief editor of the acclaimed Deep-Sea News (, a popular ocean-themed blog that has won numerous awards. His writing has been featured in Cosmos, Science Illustrated, American Scientist, Wired, Mental Floss, and the Open Lab: The Best Science Writing on the Web.