Comparing model predictions for ecosystem-based management

Nis Sand Jacobsen, Timothy E. Essington, Ken Haste Andersen

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Ecosystem modeling is becoming an integral part of fisheries management, but there is a need to identify differences between predictions derived from models employed for scientific and management purposes. Here, we compared two models: a biomass-based food-web model (Ecopath with Ecosim (EwE)) and a size-structured fish community model. The models were compared with respect to predicted ecological consequences of fishing to identify commonalities and differences in model predictions for the California Current fish community. We compared the models regarding direct and indirect responses to fishing on one or more species. The size-based model predicted a higher fishing mortality needed to reach maximum sustainable yield than EwE for most species. The size-based model also predicted stronger top-down effects of predator removals than EwE.
In contrast, EwE predicted stronger bottom-up effects of forage fisheries removal. In both cases, the differences are due to the
presumed degree of trophic overlap between juveniles of large-bodied fish and adult stages of forage fish. These differences
highlight how each model’s emphasis on distinct details of ecological processes affects its predictions, underscoring the
importance of incorporating knowledge of model assumptions and limitation, possibly through using model ensembles, when
providing model-based scientific advice to policy makers.
Original languageEnglish
JournalCanadian Journal of Fisheries and Aquatic Sciences
Volume73
Issue number4
Pages (from-to)666-676
ISSN0706-652X
DOIs
Publication statusPublished - 2016

Cite this

Jacobsen, Nis Sand ; Essington, Timothy E. ; Andersen, Ken Haste. / Comparing model predictions for ecosystem-based management. In: Canadian Journal of Fisheries and Aquatic Sciences. 2016 ; Vol. 73, No. 4. pp. 666-676.
@article{9e4439a11b36401fad6653e1bcbb29a5,
title = "Comparing model predictions for ecosystem-based management",
abstract = "Ecosystem modeling is becoming an integral part of fisheries management, but there is a need to identify differences between predictions derived from models employed for scientific and management purposes. Here, we compared two models: a biomass-based food-web model (Ecopath with Ecosim (EwE)) and a size-structured fish community model. The models were compared with respect to predicted ecological consequences of fishing to identify commonalities and differences in model predictions for the California Current fish community. We compared the models regarding direct and indirect responses to fishing on one or more species. The size-based model predicted a higher fishing mortality needed to reach maximum sustainable yield than EwE for most species. The size-based model also predicted stronger top-down effects of predator removals than EwE.In contrast, EwE predicted stronger bottom-up effects of forage fisheries removal. In both cases, the differences are due to thepresumed degree of trophic overlap between juveniles of large-bodied fish and adult stages of forage fish. These differenceshighlight how each model’s emphasis on distinct details of ecological processes affects its predictions, underscoring theimportance of incorporating knowledge of model assumptions and limitation, possibly through using model ensembles, whenproviding model-based scientific advice to policy makers.",
author = "Jacobsen, {Nis Sand} and Essington, {Timothy E.} and Andersen, {Ken Haste}",
year = "2016",
doi = "10.1139/cjfas-2014-0561",
language = "English",
volume = "73",
pages = "666--676",
journal = "Canadian Journal of Fisheries and Aquatic Sciences",
issn = "0706-652X",
publisher = "N R C Research Press",
number = "4",

}

Comparing model predictions for ecosystem-based management. / Jacobsen, Nis Sand; Essington, Timothy E.; Andersen, Ken Haste.

In: Canadian Journal of Fisheries and Aquatic Sciences, Vol. 73, No. 4, 2016, p. 666-676.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Comparing model predictions for ecosystem-based management

AU - Jacobsen, Nis Sand

AU - Essington, Timothy E.

AU - Andersen, Ken Haste

PY - 2016

Y1 - 2016

N2 - Ecosystem modeling is becoming an integral part of fisheries management, but there is a need to identify differences between predictions derived from models employed for scientific and management purposes. Here, we compared two models: a biomass-based food-web model (Ecopath with Ecosim (EwE)) and a size-structured fish community model. The models were compared with respect to predicted ecological consequences of fishing to identify commonalities and differences in model predictions for the California Current fish community. We compared the models regarding direct and indirect responses to fishing on one or more species. The size-based model predicted a higher fishing mortality needed to reach maximum sustainable yield than EwE for most species. The size-based model also predicted stronger top-down effects of predator removals than EwE.In contrast, EwE predicted stronger bottom-up effects of forage fisheries removal. In both cases, the differences are due to thepresumed degree of trophic overlap between juveniles of large-bodied fish and adult stages of forage fish. These differenceshighlight how each model’s emphasis on distinct details of ecological processes affects its predictions, underscoring theimportance of incorporating knowledge of model assumptions and limitation, possibly through using model ensembles, whenproviding model-based scientific advice to policy makers.

AB - Ecosystem modeling is becoming an integral part of fisheries management, but there is a need to identify differences between predictions derived from models employed for scientific and management purposes. Here, we compared two models: a biomass-based food-web model (Ecopath with Ecosim (EwE)) and a size-structured fish community model. The models were compared with respect to predicted ecological consequences of fishing to identify commonalities and differences in model predictions for the California Current fish community. We compared the models regarding direct and indirect responses to fishing on one or more species. The size-based model predicted a higher fishing mortality needed to reach maximum sustainable yield than EwE for most species. The size-based model also predicted stronger top-down effects of predator removals than EwE.In contrast, EwE predicted stronger bottom-up effects of forage fisheries removal. In both cases, the differences are due to thepresumed degree of trophic overlap between juveniles of large-bodied fish and adult stages of forage fish. These differenceshighlight how each model’s emphasis on distinct details of ecological processes affects its predictions, underscoring theimportance of incorporating knowledge of model assumptions and limitation, possibly through using model ensembles, whenproviding model-based scientific advice to policy makers.

U2 - 10.1139/cjfas-2014-0561

DO - 10.1139/cjfas-2014-0561

M3 - Journal article

VL - 73

SP - 666

EP - 676

JO - Canadian Journal of Fisheries and Aquatic Sciences

JF - Canadian Journal of Fisheries and Aquatic Sciences

SN - 0706-652X

IS - 4

ER -