Inclusion of jellyfish in 30+ years of Ecopath with Ecosim models

Abstract

Abstract A review of the functional role of jellyfish in Ecopath with Ecosim (EwE) models by Pauly et al. [Pauly, D., Graham, W., Libralato, S., Morissette, L., and Deng Palomares, M. L. 2009. Jellyfish in ecosystems, online databases, and ecosystem models. Hydrobiologia, 616: 67–85.] a decade ago concluded that recreation of jellyfish population dynamics in models required additional ecological research and the careful consideration of their unique biology during model construction. Here, amidst calls for ecosystem-based management and the growing recognition of jellyfishes' role in foodwebs, we investigate how jellyfish are implemented in EwE models and identify areas requiring improvement. Over time, an increasing percentage of models have included jellyfish. Jellyfish were often linked to the wider ecosystem, with many predators and prey included in models. However, ecotrophic efficiency, a measure of the extent to which they are used by higher trophic levels, was frequently set at low values, suggesting that jellyfish are still perceived as under-utilized components of the ecosystem. Moving forward, greater care should be taken to differentiate the functional roles played by ctenophores, cnidarians, and pelagic tunicates. Additionally, when feasible, early life stages should be incorporated as multi-stanza groups to more accurately depict jellyfishes' complex life cycle.