LAUSR

Abstract There are several emergent properties useful as indicators of marine ecosystem status. Some of these are based on the cumulative trophic theory, which posits that biomass and production accumulate in repeatable and predictable patterns across trophic levels. These patterns result in a suite of curve parameters that can delineate when a marine ecosystem is undergoing perturbation or recovery. When looking at this suite of curve parameters, and their trajectories over time, a clear sense of perturbation, recovery, or transition can be delineated. From a set of over 3700 observations we established empirical threshold levels for the curve parameters, i.e., Trophic Level inflection point, Biomass inflection point and Steepness at 3.38 ± 0.05, 0.33 ± 0.01 and 0.50 ± 0.56, respectively. When the three parameters are examined collectively to determine whether a particular ecosystem datum was below or above each of these three thresholds, clear three-dimensional patterns emerged. First, some volumes in this 3-D space of parameters simply did not have data, and many volumes had very little. The majority of data (approximately 40%) occurred in situations with Steepness and Biomass inflection point higher than thresholds. Almost none of the ecosystems (