A quantitative technique for sampling motile macroinvertebrates in beds of the seagrass Posidonia oceanica (L.) Delile

• Main Authors: Joseph A. Borg, Martin J. Attrill, Ashley A. Rowden, Patrick J. Schembri, Malcolm B. Jones
• Format: Article
• Language: English
• Published: Consejo Superior de Investigaciones Científicas 2002-03-01
• Series: Scientia Marina
• Subjects: sampling; seagrass; macroinvertebrates; posidonia oceanica; corer; mediterranean sea; malta
• Online Access: http://scientiamarina.revistas.csic.es/index.php/scientiamarina/article/view/563

Techniques for sampling motile macroinvertebrates associated with Posidonia oceanica seagrass meadows have mainly involved the use of hand-nets and suction samplers or collection by hand. These techniques give unreliable quantitative estimates or have practical difficulties. A large cylindrical saw-rimmed corer was designed and used successfully to obtain quantitative samples of macroinvertebrates from both foliage and root-rhizome matrix of a Posidonia oceanica meadow in Malta (central Mediterranean). Choice of the appropriate sample unit size was assessed by comparing the relative accuracy, precision and efficiency of three different core diameters: 25 cm, 35 cm and 45 cm. The results suggest that for comparison of macrofaunal species richness and abundance between different meadows/sites the 25 cm diameter corer is recommended. For surveys aimed at estimating total diversity within a particular site, the 35 cm diameter corer is more appropriate.