Length-mass relationships for aquatic insects of Navarino Island, extreme southern Chile

Biomass is a key parameter in ecology, as it provides insight into ecosystem functioning. Length-mass estimations are widely used for this purpose due to the relatively simple and straightforward procedures required. In this study, we conducted the first assessment of length-mass relationships for 25 aquatic insect species from the Magellanic sub-Antarctic ecoregion of Chile. There were strong linear correlations between the mass and size of the study species. We found a low proportion of change in mass associated with length increase, for most species, given the obtained b values, which could indicate recent molts, incomplete chitinization, and/or dominance of early developmental stages. While the estimated parameters from linear and non-linear regressions were similar to those reported in other studies, we emphasize that simple extrapolation from other areas should be avoided due to the inherent variability of each ecosytem. The collection of length-mass estimation data provides important information on biomass and secondary production, key parameters of functional diversity.