An efficient method for collecting large samples of live copepods free from detritus
Carl J. Svensson A C , Glenn A. Hyndes B and Paul S. Lavery BA School of Biological, Earth and Environmental Sciences, and Centre for Marine Bio-Innovation, University of New South Wales, Sydney, NSW 2052, Australia.
B Centre for Marine Ecosystems Research, School of Natural Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027, Australia.
C Corresponding author. Email: carl-johan.svensson@marecol.gu.se
Marine and Freshwater Research 61(5) 621-624 https://doi.org/10.1071/MF09178
Submitted: 13 July 2009 Accepted: 20 September 2009 Published: 28 May 2010
Abstract
Meiofauna are often important in the transfer of organic material to higher trophic levels in aquatic environments. However, in food web analysis the group is frequently pooled or ignored owing to the difficulty in isolating individual components of the assemblage. In this study, we developed and tested a new method for extracting photopositive and detritus-free copepod samples from sediments, and compared this method to a previous technique (Couch 1989). In our initial trials, ∼400 copepods (all orders included) were collected in 15 min compared with 60 copepods using Couch’s method. In subsequent trials that focussed on specific orders of copepods, our method was at least 10 times more efficient than Couch’s method at collecting cyclopoid and harpacticoid copepods from sediments. The new method requires very little supervision and there is no requirement for a particular intensity of light. This method can increase the collection of large numbers of photopositive copepods in aquatic systems, and thereby facilitate the inclusion of this important component into future food web studies, particularly those using biomarkers such as stable isotopes or fatty acids.
Additional keywords: copepods, cyclopoids, extraction efficiency, harpacticoids, meiofauna, photopositive, sampling.
Acknowledgement
We thank Jo-Anne Blunn for her help in collecting sediment samples and carrying out the efficiency experiment. We also thank the two anonymous referees and the editor for constructive comments that helped improve this manuscript. This study was jointly funded by Edith Cowan University (ECU), the Swedish research council FORMAS, project No. 2007–449, and the Western Australian Department of Water. The research was conducted under the approval of the ECU animal ethics committee.
Aarseth, K. A. , and Schram, T. A. (1999). Wavelength specific behaviour in Lepeoptheirus salmonis and Calanus finmarchicus to ultraviolet and visible light in laboratory experiments (Crustacea : Copepoda). Marine Ecology Progress Series 186, 211–217.
| Crossref | GoogleScholarGoogle Scholar |
Pace, M. C. , and Carman, K. R. (1996). Interspecific differences among meiobenthic copepods in the use of microalgal food resources. Marine Ecology Progress Series 143, 77–86.
| Crossref | GoogleScholarGoogle Scholar |
Rzeznik-Orignac, J. , Fichet, D. , and Boucher, G. (2004). Extracting massive numbers of nematodes from muddy marine deposits: efficiency and selectivity. Nematology 6, 605–616.
| Crossref | GoogleScholarGoogle Scholar |
Rzeznik-Orignac, J. , Boucher, G. , Fichet, D. , and Richard, P. (2008). Stable isotope analysis of food source and trophic position of intertidal nematodes and copepods. Marine Ecology Progress Series 359, 145–150.
| Crossref | GoogleScholarGoogle Scholar |
Stearns, D. E. , and Forward, R. B. (1984). Copepod photobehaviour in a simulated natural light environment and its relation to nocturnal vertical migration. Marine Biology 82, 91–100.
| Crossref | GoogleScholarGoogle Scholar |
Svensson, C. J. , Hyndes, G. A. , and Lavery, P. S. (2007). Food web analyses in two permanently open temperate estuaries; consequences of saltmarsh loss. Marine Environmental Research 64, 286–304.
| Crossref | GoogleScholarGoogle Scholar | CAS | PubMed |
