Acoustic surveys of Antarctic krill have been conducted at South Georgia along standard transects within two 100 x 80 km survey boxes for four consecutive austral summers since 1995/96. Mean krill abundance varied substantially between boxes and years. Here we use analysis of variance of individual survey transect mean krill densities to investigate the relative importance and scale of temporal and spatial variability to observed changes in overall mean krill abundance. We did not detect any significant effect of spatial position between transect means averaged over the four years. However, all other sources of variation and interactions were significant. Estimated components of variance showed that the inter-annual variability was very similar in magnitude between boxes and between transects, indicating that krill distribution patterns are extremely patchy in both space and time across spatial scales between 5-10 km and 100-200 km. Separate analyses for each box revealed that there was no statistically significant inter-annual variation in the survey box to the north west of the island.
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