Estimating biomass of benthic kelp forest invertebrates from body size and percent cover data
The inability to compare different measures of species abundance (such as density and percent cover) or different metrics of species biomass (such as wet mass and ash-free dry mass) hampers quantitative studies of community dynamics, trophic interactions, energy flow and biodiversity. This has been especially problematic for the dynamic and highly productive communities inhabiting shallow reefs in temperate seas where varied metrics are commonly used to characterize the abundance and biomass of different suites of species. To facilitate the conversion of abundance data into common metrics of biomass, we developed quantitative relationships between wet mass and length and wet mass and percent cover, and conversion factors for transforming wet mass into dry mass, shell-free and decalcified dry mass, and ash-free dry mass for 84 species of benthic macroinvertebrates common to giant kelp forests in southern California. Regressions for all 84 species were highly significant, and regression fits were very good for most species. Interspecific differences between regression slopes and in the ratios used to convert one metric of mass into another varied by as much as an order of magnitude among species within the same taxonomic group indicating that caution should be used when attempting to estimate biomass using generic relationships or ratios that were developed for other species, even if those species are closely related.
We thank the many students who assisted in the collection and processing of specimens, especially K. Stolzenbach. This material is based on the support by the U.S. National Science Foundation’s Long Term Ecological Research Program under Grant Numbers OCE 0620276 and OCE 1232779.
- DeMartini EE, Barnett AM, Johnson TD, Ambrose RF (1984) Growth and reproduction estimates for biomass-dominant fishes on a southern California artificial reef. Bull Mar Sci 55:484–500Google Scholar
- Holme NA, McIntyre AD (1984) Methods for the study of marine benthos. IBP handbook No. 16. Blackwell Scientific, OxfordGoogle Scholar
- Love MS (2011) Certainly more than you want to know about the fishes of the Pacific Coast. A postmodern experience. Really Big Press, Santa BarbaraGoogle Scholar
- Quast JC (1968a) Estimates of the population and standing crop of fishes. Calif Fish Game Fish Bull 139:57–79Google Scholar
- Quast JC (1968b) Fish fauna of the rocky inshore zone. Calif Fish Game Fish Bull 139:35–55Google Scholar
- Robinson L, Greenstreet S, Reiss H, Callaway R, Craeymeersch J, de Boois I, Degraer S, Ehrich S, Fraser H, Goffin A, Kroncke I, Jorgenson L, Robertson M, Lancaster J (2010) Length–weight relationships of 216 North Sea benthic invertebrates and fish. J Mar Biol Assoc UK 90:95–104CrossRefGoogle Scholar
- Underwood AJ, Denley EJ (1984) Paradigms, explanations and generalizations in models for the structure of intertidal communities on rocky shores. In: Strong DR, Simberloff D, Abele LG, Thistle A (eds) Ecological communities: conceptual issues and the evidence. Princeton University Press, Princeton, pp 151–180Google Scholar
- Wernberg TD, Smale A, Tuya F, Thomsen MS, Langlois TJ, De Bettignies T, Bennett S, Rousseaux CS (2013) An extreme climatic event alters marine ecosystem structure in a global biodiversity hotspot. Nat Clim Change 400:78–82Google Scholar