Predicting the population-level impact of mitigating harbor porpoise bycatch with pingers and time-area fishing closures
Unintentional mortality of higher trophic-level species in commercial fisheries (bycatch) represents a major conservation concern as it may influence the long-term persistence of populations. An increasingly common strategy to mitigate bycatch of harbor porpoises (Phocoena phocoena), a small and pro...
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ftuniaarhuspubl:oai:pure.atira.dk:publications/b35077ca-55ae-439a-8588-32ae4d8e52f1 2024-02-04T10:03:56+01:00 Predicting the population-level impact of mitigating harbor porpoise bycatch with pingers and time-area fishing closures van Beest, Floris Kindt-Larsen, Lotte Bastardie, Francois Bartolino, Valerio Nabe-Nielsen, Jacob 2017-05-01 https://pure.au.dk/portal/en/publications/b35077ca-55ae-439a-8588-32ae4d8e52f1 eng eng https://pure.au.dk/portal/en/publications/b35077ca-55ae-439a-8588-32ae4d8e52f1 info:eu-repo/semantics/restrictedAccess van Beest , F , Kindt-Larsen , L , Bastardie , F , Bartolino , V & Nabe-Nielsen , J 2017 , ' Predicting the population-level impact of mitigating harbor porpoise bycatch with pingers and time-area fishing closures ' , Annual Conference of the European Cetacean Society 2017 , Middelfart , Denmark , 29/04/2017 - 03/05/2017 . Acoustic alarms Agent-based model Bycatch Cetaceans Disturbance Gillnet fisheries Marine mammals Phocoena phocoena Population dynamics Time-area fishing closures Underwater noise conferenceObject 2017 ftuniaarhuspubl 2024-01-11T00:00:03Z Unintentional mortality of higher trophic-level species in commercial fisheries (bycatch) represents a major conservation concern as it may influence the long-term persistence of populations. An increasingly common strategy to mitigate bycatch of harbor porpoises (Phocoena phocoena), a small and protected marine top predator, involves the use of pingers (acoustic alarms that emit underwater noise) and time-area fishing closures. Although these mitigation measures can reduce harbor porpoise bycatch in gillnet fisheries considerably, inference about the long-term population-level consequences is currently lacking. We developed a spatially explicit individual-based simulation model (IBM) with the aim to evaluate the effectiveness of these two bycatch mitigation measures. We quantified both the direct positive effects (i.e., reduced bycatch) and any indirect negative effects (i.e., reduced foraging efficiency) on the population size using the inner Danish waters as a biological system. The model incorporated empirical data on gillnet fishing effort and noise avoidance behavior by free-ranging harbor porpoises exposed to randomized high-frequency (20- to 160-kHz) pinger signals. The IBM simulations revealed a synergistic relationship between the implementation of time-area fishing closures and pinger deployment. Time-area fishing closures reduced bycatch rates substantially but not completely. In contrast, widespread pinger deployment resulted in total mitigation of bycatch but frequent and recurrent noise avoidance behavior in high-quality foraging habitat negatively affected individual survival and the total population size. When both bycatch mitigation measures were implemented simultaneously, the negative impact of pinger noiseinduced sub-lethal behavioral effects on the population was largely eliminated with a positive effect on the population size that was larger than when the mitigation measures were used independently. Our study highlights that conservationists and policy makers need to consider and balance ... Conference Object Phocoena phocoena Aarhus University: Research |
institution |
Open Polar |
collection |
Aarhus University: Research |
op_collection_id |
ftuniaarhuspubl |
language |
English |
topic |
Acoustic alarms Agent-based model Bycatch Cetaceans Disturbance Gillnet fisheries Marine mammals Phocoena phocoena Population dynamics Time-area fishing closures Underwater noise |
spellingShingle |
Acoustic alarms Agent-based model Bycatch Cetaceans Disturbance Gillnet fisheries Marine mammals Phocoena phocoena Population dynamics Time-area fishing closures Underwater noise van Beest, Floris Kindt-Larsen, Lotte Bastardie, Francois Bartolino, Valerio Nabe-Nielsen, Jacob Predicting the population-level impact of mitigating harbor porpoise bycatch with pingers and time-area fishing closures |
topic_facet |
Acoustic alarms Agent-based model Bycatch Cetaceans Disturbance Gillnet fisheries Marine mammals Phocoena phocoena Population dynamics Time-area fishing closures Underwater noise |
description |
Unintentional mortality of higher trophic-level species in commercial fisheries (bycatch) represents a major conservation concern as it may influence the long-term persistence of populations. An increasingly common strategy to mitigate bycatch of harbor porpoises (Phocoena phocoena), a small and protected marine top predator, involves the use of pingers (acoustic alarms that emit underwater noise) and time-area fishing closures. Although these mitigation measures can reduce harbor porpoise bycatch in gillnet fisheries considerably, inference about the long-term population-level consequences is currently lacking. We developed a spatially explicit individual-based simulation model (IBM) with the aim to evaluate the effectiveness of these two bycatch mitigation measures. We quantified both the direct positive effects (i.e., reduced bycatch) and any indirect negative effects (i.e., reduced foraging efficiency) on the population size using the inner Danish waters as a biological system. The model incorporated empirical data on gillnet fishing effort and noise avoidance behavior by free-ranging harbor porpoises exposed to randomized high-frequency (20- to 160-kHz) pinger signals. The IBM simulations revealed a synergistic relationship between the implementation of time-area fishing closures and pinger deployment. Time-area fishing closures reduced bycatch rates substantially but not completely. In contrast, widespread pinger deployment resulted in total mitigation of bycatch but frequent and recurrent noise avoidance behavior in high-quality foraging habitat negatively affected individual survival and the total population size. When both bycatch mitigation measures were implemented simultaneously, the negative impact of pinger noiseinduced sub-lethal behavioral effects on the population was largely eliminated with a positive effect on the population size that was larger than when the mitigation measures were used independently. Our study highlights that conservationists and policy makers need to consider and balance ... |
format |
Conference Object |
author |
van Beest, Floris Kindt-Larsen, Lotte Bastardie, Francois Bartolino, Valerio Nabe-Nielsen, Jacob |
author_facet |
van Beest, Floris Kindt-Larsen, Lotte Bastardie, Francois Bartolino, Valerio Nabe-Nielsen, Jacob |
author_sort |
van Beest, Floris |
title |
Predicting the population-level impact of mitigating harbor porpoise bycatch with pingers and time-area fishing closures |
title_short |
Predicting the population-level impact of mitigating harbor porpoise bycatch with pingers and time-area fishing closures |
title_full |
Predicting the population-level impact of mitigating harbor porpoise bycatch with pingers and time-area fishing closures |
title_fullStr |
Predicting the population-level impact of mitigating harbor porpoise bycatch with pingers and time-area fishing closures |
title_full_unstemmed |
Predicting the population-level impact of mitigating harbor porpoise bycatch with pingers and time-area fishing closures |
title_sort |
predicting the population-level impact of mitigating harbor porpoise bycatch with pingers and time-area fishing closures |
publishDate |
2017 |
url |
https://pure.au.dk/portal/en/publications/b35077ca-55ae-439a-8588-32ae4d8e52f1 |
genre |
Phocoena phocoena |
genre_facet |
Phocoena phocoena |
op_source |
van Beest , F , Kindt-Larsen , L , Bastardie , F , Bartolino , V & Nabe-Nielsen , J 2017 , ' Predicting the population-level impact of mitigating harbor porpoise bycatch with pingers and time-area fishing closures ' , Annual Conference of the European Cetacean Society 2017 , Middelfart , Denmark , 29/04/2017 - 03/05/2017 . |
op_relation |
https://pure.au.dk/portal/en/publications/b35077ca-55ae-439a-8588-32ae4d8e52f1 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
_version_ |
1789971780145774592 |