University of Tasmania
Browse

File(s) under permanent embargo

The paradox of inverted biomass pyramids in kelp forest fish communities

journal contribution
posted on 2023-05-18, 20:19 authored by Rowan TrebilcoRowan Trebilco, Dulvy, NK, Anderson, SC, Salomon, AK
Theory predicts that bottom-heavy biomass pyramids or ‘stacks’ should predominate in real-world communities if trophic-level increases with body size (mean predator-to-prey mass ratio (PPMR) more than 1). However, recent research suggests that inverted biomass pyramids (IBPs) characterize relatively pristine reef fish communities. Here, we estimated the slope of a kelp forest fish community biomass spectrum from underwater visual surveys. The observed biomass spectrum slope is strongly positive, reflecting an IBP. This is incongruous with theory because this steep positive slope would only be expected if trophic position decreased with increasing body size (consumer-to-resource mass ratio, less than 1). We then used δ15N signatures of fish muscle tissue to quantify the relationship between trophic position and body size and instead detected strong evidence for the opposite, with PPMR ≈ 1650 (50% credible interval 280–12 000). The natural history of kelp forest reef fishes suggests that this paradox could arise from energetic subsidies in the form of movement of mobile consumers across habitats, and from seasonally pulsed production inputs at small body sizes. There were four to five times more biomass at large body sizes (1–2 kg) than would be expected in a closed steady-state community providing a measure of the magnitude of subsidies.

History

Publication title

Proceedings of the Royal Society of London: Biological Sciences

Volume

283

Issue

1833

Article number

20160816

Number

20160816

Pagination

1-9

ISSN

0962-8436

Department/School

Institute for Marine and Antarctic Studies

Publisher

Royal Soc London

Place of publication

6 Carlton House Terrace, London, England, Sw1Y 5Ag

Rights statement

Copyright 2016 The Author(s)

Repository Status

  • Restricted

Socio-economic Objectives

Assessment and management of terrestrial ecosystems

Usage metrics

    University Of Tasmania

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC