Quantification of iceberg impact and benthic recolonisation patterns in the Weddell Sea (Antarctica)

Abstract.

Video transects in the eastern Weddell Sea were used to classify the mega-epibenthos into stages of recolonisation after iceberg impact and unaffected fauna. Three site categories differing in bottom topography and concentration of grounded icebergs were analysed. At small iceberg banks and on a comparatively plain seabed, 52–60% of undisturbed seafloor was found, and below 20% at a large iceberg bank. The impact was calculated as a function of values for recently disturbed areas and an estimated recovery time. The results show that, statistically, the Antarctic benthos never reaches peak maturity and that iceberg scouring is among the five most significant disturbances that any large ecosystem on earth experiences.