Graphics by Pieter Daniël van Denderen

Emergent fish food web biogeography

Tuesday 13 Jul 21



Ken Haste Andersen
Professor, Head of Section
DTU Aqua
+45 35 88 33 99

Fish are vertically structured in the water column and this affects what they eat and by whom they are eaten. A new Ocean Life paper has extended the recent FEISTY fish community model to resolve the vertical structure of a fish community. The new model was used to predict the biogeography of marine fish food webs across ocean biomes and to estimate fish ecosystem functions.

Fish live at different depths. Some species are pelagic and live in the upper sunlit ocean. Others are feeding on benthos and are abundant in areas where life at the seafloor is plentiful. In between these groups are the mesopelagic fish that live in the twilight zone during the day and migrate up in the water during the night. This vertical variation in fish has been recognized as important for predicting fisheries production under climate change and for quantifying the role of fish in carbon and nutrient cycling. In this study, we show how a trait-based approach can be used to obtain structurally different food web types that predictably vary with seafloor depth and ocean productivity across ocean biomes.

The trait-based configuration used diversified possible fish guilds, food web structures and energy flows compared to the more commonly used size-based models. This diversification enables practical applications that have hitherto been elusive. For example, fisheries assessments of mesopelagic fish in the open seas and the quantification of carbon export to depth by fish.

Read the paper here:

van Denderen PD, CM Petrik, CA Stock & KH Andersen (2021) Emergent global biogeography of marine fish food webs Global Ecology and Biogeography
8 AUGUST 2022