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Stepien EN, Galatius A, Hansen KA, Nabe-Nielsen J, Teilmann J, Wahlberg M. Response of Eurasian otters (Lutra lutra) to underwater acoustic harassment device sounds. Sci Rep 2024; 14:4988. [PMID: 38424202 PMCID: PMC10904746 DOI: 10.1038/s41598-024-55481-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 02/23/2024] [Indexed: 03/02/2024] Open
Abstract
Seal scarers (or acoustic harassment devices, AHDs) are designed to deter seals from fishing gear and aquaculture operations, as well as to prevent seals from entering rivers to avoid predation on valuable fish. Our study investigated the potential effects of AHDs on non-target species, specifically the Eurasian otters (Lutra lutra), by testing the reaction of two rehabilitated otters to simulated AHDs sounds at 1 and 14 kHz, with a received sound intensity of 105-145 dB re 1 µPa rms. The 1 kHz sounds were used to investigate alternative frequencies for scaring seals without scaring otters. The otters reacted to both 1 and 14 kHz tonal signals when retrieving fish from a feeding station 0.8 m below the surface. Their diving behaviour and time to extract food progressively increased as sound intensity increased for all tested sound levels. Notably, the sound levels used in our tests were significantly lower (40-80 dB) than the source levels from commercial AHDs. These findings highlight the importance of caution when using AHDs in river and sea habitats inhabited by otters, as AHDs can change their behaviour and potentially result in habitat exclusion.
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Affiliation(s)
| | - Anders Galatius
- Marine Mammal Research, Department of Ecoscience, Aarhus University, Aarhus, Denmark
| | - Kirstin Anderson Hansen
- Marine Biological Research Centre, Department of Biology, University of Southern Denmark, Odense, Denmark
| | - Jacob Nabe-Nielsen
- Marine Mammal Research, Department of Ecoscience, Aarhus University, Aarhus, Denmark
| | - Jonas Teilmann
- Marine Mammal Research, Department of Ecoscience, Aarhus University, Aarhus, Denmark
| | - Magnus Wahlberg
- Marine Biological Research Centre, Department of Biology, University of Southern Denmark, Odense, Denmark
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2
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McKeegan KA, Clayton K, Williams R, Ashe E, Reiss S, Mendez-Bye A, Janik VM, Goetz T, Zinkgraf M, Acevedo-Gutiérrez A. The effect of a startle-eliciting device on the foraging success of individual harbor seals (Phoca vitulina). Sci Rep 2024; 14:3719. [PMID: 38355948 PMCID: PMC10866881 DOI: 10.1038/s41598-024-54175-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 02/09/2024] [Indexed: 02/16/2024] Open
Abstract
Pinniped predation on commercially and ecologically important prey has been a source of conflict for centuries. In the Salish Sea, harbor seals (Phoca vitulina) are suspected of impeding the recovery of culturally and ecologically critical Pacific salmon (Oncorhynchus spp.). In Fall 2020, a novel deterrent called Targeted Acoustic Startle Technology (TAST) was deployed at Whatcom Creek to deter harbor seals from preying on fall runs of hatchery chum (O. keta) and Chinook (O. tshawytscha) salmon in Bellingham, Washington, USA. Field observations were conducted in 2020 to compare the presence and foraging success of individual harbor seals across sound exposure (TAST-on) and control (TAST-off) conditions. Observations conducted the previous (2019) and following (2021) years were used to compare the effects observed in 2020 to two control years. Using photo-identification, individual seals were associated with foraging successes across all 3 years of the study. Generalized linear mixed models showed a significant 45.6% reduction in the duration (min) individuals remained at the creek with TAST on, and a significant 43.8% reduction in the overall foraging success of individuals. However, the observed effect of TAST varied across individual seals. Seals that were observed regularly within one season were more likely to return the year after, regardless of TAST treatment. Generalized linear models showed interannual variation in the number of seals present and salmon consumed. However, the effect of TAST in 2020 was greater than the observed variation across years. Our analyses suggest TAST can be an effective tool for managing pinniped predation, although alternate strategies such as deploying TAST longer-term and using multi-unit setups to increase coverage could help strengthen its effects. Future studies should further examine the individual variability found in this study.
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Affiliation(s)
- Kathleen A McKeegan
- Biology Department, Western Washington University, Bellingham, WA, 98225, USA.
- Research and Recovery Program, Skagit River System Cooperative, P.O. Box 368, La Conner, WA, 98257-0368, USA.
| | - Kate Clayton
- Biology Department, Western Washington University, Bellingham, WA, 98225, USA
| | - Rob Williams
- Oceans Initiative, 117 E Louisa St. #135, Seattle, WA, 98102, USA
| | - Erin Ashe
- Oceans Initiative, 117 E Louisa St. #135, Seattle, WA, 98102, USA
| | - Stephanie Reiss
- Oceans Initiative, 117 E Louisa St. #135, Seattle, WA, 98102, USA
| | | | - Vincent M Janik
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, East Sands, St Andrews, Fife, KY16 8LB, UK
| | - Thomas Goetz
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, East Sands, St Andrews, Fife, KY16 8LB, UK
| | - Matthew Zinkgraf
- Biology Department, Western Washington University, Bellingham, WA, 98225, USA
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3
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Goller B, Baumhardt P, Dominguez-Villegas E, Katzner T, Fernández-Juricic E, Lucas JR. Selecting auditory alerting stimuli for eagles on the basis of auditory evoked potentials. CONSERVATION PHYSIOLOGY 2022; 10:coac059. [PMID: 36134144 PMCID: PMC9486983 DOI: 10.1093/conphys/coac059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 07/11/2022] [Accepted: 09/13/2022] [Indexed: 06/16/2023]
Abstract
Development of wind energy facilities results in interactions between wildlife and wind turbines. Raptors, including bald and golden eagles, are among the species known to incur mortality from these interactions. Several alerting technologies have been proposed to mitigate this mortality by increasing eagle avoidance of wind energy facilities. However, there has been little attempt to match signals used as alerting stimuli with the sensory capabilities of target species like eagles. One potential approach to tuning signals is to use sensory physiology to determine what stimuli the target eagle species are sensitive to even in the presence of background noise, thereby allowing the development of a maximally stimulating signal. To this end, we measured auditory evoked potentials of bald and golden eagles to determine what types of sounds eagles can process well, especially in noisy conditions. We found that golden eagles are significantly worse than bald eagles at processing rapid frequency changes in sounds, but also that noise effects on hearing in both species are minimal in response to rapidly changing sounds. Our findings therefore suggest that sounds of intermediate complexity may be ideal both for targeting bald and golden eagle hearing and for ensuring high stimulation in noisy field conditions. These results suggest that the sensory physiology of target species is likely an important consideration when selecting auditory alerting sounds and may provide important insight into what sounds have a reasonable probability of success in field applications under variable conditions and background noise.
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Affiliation(s)
- Benjamin Goller
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Patrice Baumhardt
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
| | | | - Todd Katzner
- U.S. Geological Survey, Forest & Rangeland Ecosystem Science Center, 230 N Collins Rd., Boise, ID 83702, USA
| | | | - Jeffrey R Lucas
- Corresponding author: Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA. Tel: 765-494-8112.
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4
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Todd VLG, Williamson LD, Jiang J, Cox SE, Todd IB, Ruffert M. Prediction of marine mammal auditory-impact risk from Acoustic Deterrent Devices used in Scottish aquaculture. MARINE POLLUTION BULLETIN 2021; 165:112171. [PMID: 33621906 DOI: 10.1016/j.marpolbul.2021.112171] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/08/2021] [Accepted: 02/10/2021] [Indexed: 06/12/2023]
Abstract
Acoustic Deterrent Devices (ADDs) are used worldwide to deter pinnipeds from predating fish-aquaculture facilities. Desk-based noise-propagation modelling of six commercial ADD models, and a 'fictional' ADD was performed, the latter involving alternating source level, frequency, duty cycle, noise-exposure duration, and number of ADDs active simultaneously. Potential auditory impacts on marine mammals were explored using the Southall et al. (2019) criteria. Depending on operational characteristics, real ADDs were predicted to cause Temporary Threshold Shift (TTS) to Very High Frequency (VHF) cetaceans at ranges of 4-31 km, and a single fictional device operating at the highest outputs tested was predicted to cause TTS to VHF cetaceans at up to 32 km. Cumulative effects of 23 real fish-farm ADDs produced noise across large swathes of the Inner-Hebrides. The single variable causing greatest reduction in potential impact to marine mammals from fictional ADDs was SL.
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Affiliation(s)
- Victoria L G Todd
- Ocean Science Consulting Limited, Spott Road, Dunbar, East Lothian, Scotland, EH42 1RR, UK.
| | - Laura D Williamson
- Ocean Science Consulting Limited, Spott Road, Dunbar, East Lothian, Scotland, EH42 1RR, UK.
| | - Jian Jiang
- Ocean Science Consulting Limited, Spott Road, Dunbar, East Lothian, Scotland, EH42 1RR, UK.
| | - Sophie E Cox
- Ocean Science Consulting Limited, Spott Road, Dunbar, East Lothian, Scotland, EH42 1RR, UK.
| | - Ian B Todd
- Ocean Science Consulting Limited, Spott Road, Dunbar, East Lothian, Scotland, EH42 1RR, UK.
| | - Maximilian Ruffert
- School of Mathematics & Maxwell Institute, University of Edinburgh, Edinburgh EH9 3FD, Scotland, UK.
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5
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Allyn EM, Scordino JJ. Entanglement rates and haulout abundance trends of Steller (Eumetopias jubatus) and California (Zalophus californianus) sea lions on the north coast of Washington state. PLoS One 2020; 15:e0237178. [PMID: 32841298 PMCID: PMC7447031 DOI: 10.1371/journal.pone.0237178] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 07/21/2020] [Indexed: 11/20/2022] Open
Abstract
Entanglements affect marine mammal species around the globe, and for some, those impacts are great enough to cause population declines. This study aimed to document rates and causes of entanglement and trends in local haulout abundance for Steller and California sea lions on the north coast of Washington from 2010–2018. We conducted small boat surveys to count sea lions and document entangled individuals. Rates of entanglement and entangling material occurrence were compared with records of stranded individuals on the Washington and Oregon coast and with packing bands recorded during beach debris surveys. The rate of entanglement for California sea lions was 2.13%, almost entirely composed of adult males, with a peak rate during June and July potentially due to some entangled individuals not migrating to their breeding grounds. For Steller sea lions, the rate of entanglement was 0.41%, composed of 77% adults (32.4% male, 63.3% female), 17.1% juveniles, 5.9% unknown age, and no pups. Steller sea lions exhibited a 7.9% ± 3.2 rate of increase in abundance at the study haulouts, which was similar to that seen in California sea lions (7.8% ± 4.2); both increases were greater than the population growth rates observed range-wide despite high rates of entanglement. Most entanglements for both species were classified as packing bands, followed by entanglement scars. Salmon flashers were also prevalent and only occurred from June–September during the local ocean salmon troll fishery. Packing band occurrence in beach debris surveys correlated with packing band entanglements observed on haulouts. However, no packing band entanglements were observed in the stranding record and the rate of stranded animals exhibiting evidence of entanglement was lower than expected, indicating that entanglement survival is higher than previously assumed. Future studies tracking individual entanglement outcomes are needed to develop effective, targeted management strategies.
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Affiliation(s)
- Elizabeth Marina Allyn
- Marine Mammal Program, Makah Fisheries Management, Makah Tribe, Neah Bay, Washington, United States of America
- * E-mail:
| | - Jonathan Joseph Scordino
- Marine Mammal Program, Makah Fisheries Management, Makah Tribe, Neah Bay, Washington, United States of America
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6
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Götz T, Pacini AF, Nachtigall PE, Janik VM. The startle reflex in echolocating odontocetes: basic physiology and practical implications. ACTA ACUST UNITED AC 2020; 223:223/5/jeb208470. [PMID: 32165452 PMCID: PMC7075047 DOI: 10.1242/jeb.208470] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 01/24/2020] [Indexed: 11/29/2022]
Abstract
The acoustic startle reflex is an oligo-synaptic reflex arc elicited by rapid-onset sounds. Odontocetes evolved a range of specific auditory adaptations to aquatic hearing and echolocation, e.g. the ability to downregulate their auditory sensitivity when emitting clicks. However, it remains unclear whether these adaptations also led to changes of the startle reflex. We investigated reactions to startling sounds in two bottlenose dolphins (Tursiops truncatus) and one false killer whale (Pseudorca crassidens). Animals were exposed to 50 ms, 1/3 octave band noise pulses of varying levels at frequencies of 1, 10, 25 and 32 kHz while positioned in a hoop station. Startle responses were quantified by measuring rapid muscle contractions using a three-dimensional accelerometer attached to the dolphin. Startle magnitude increased exponentially with increasing received levels. Startle thresholds were frequency dependent and ranged from 131 dB at 32 kHz to 153 dB at 1 kHz (re. 1 µPa). Startle thresholds only exceeded masked auditory AEP thresholds of the animals by 47 dB but were ∼82 dB above published behavioural audiograms for these species. We also tested the effect of stimulus rise time on startle magnitude using a broadband noise pulse. Startle responses decreased with increasing rise times from 2 to 100 ms. Models suggested that rise times of 141–220 ms were necessary to completely mitigate startle responses. Our data showed that the startle reflex is conserved in odontocetes and follows similar principles as in terrestrial mammals. These principles should be considered when assessing and mitigating the effects of anthropogenic noise on marine mammals. Summary: The acoustic startle reflex is conserved in echolocating toothed whales and should be considered when predicting marine mammal responses to human-generated underwater noise.
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Affiliation(s)
- Thomas Götz
- Sea Mammal Research Unit, Scottish Oceans Institute, School of Biology, University of St Andrews, Fife KY16 8LB, UK
| | - Aude F Pacini
- Hawaii Institute of Marine Biology, University of Hawaii at Manoa, P.O. Box 1346, Kaneohe, Hawaii 96744, USA
| | - Paul E Nachtigall
- Hawaii Institute of Marine Biology, University of Hawaii at Manoa, P.O. Box 1346, Kaneohe, Hawaii 96744, USA
| | - Vincent M Janik
- Sea Mammal Research Unit, Scottish Oceans Institute, School of Biology, University of St Andrews, Fife KY16 8LB, UK
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7
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The in-air auditory thresholds of the eurasian otter (Lutra lutra, L. 1758) as determined by auditory brainstem responses. Hear Res 2019; 381:107774. [PMID: 31408801 DOI: 10.1016/j.heares.2019.107774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 07/19/2019] [Accepted: 07/31/2019] [Indexed: 11/21/2022]
Abstract
As of yet there is no literature record of the hearing range of the Eurasian otter (Lutra lutra, L. 1758), a key species for natural conservation efforts in Europe. We recorded in-air pure tone hearing thresholds of anaesthetized otters using auditory brainstem responses (ABR) and report the results of the Eurasian otter. The recorded potentials showed the typical mammalian auditory brainstem response consisting of 5 distinct positive peaks during the first 10 ms after stimulus onset. At 80 dB SPL the hearing ranged from around 200 Hz to 32 kHz, with lowest thresholds around 4 kHz.
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8
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Bedoya-Pérez MA, Smith KL, Kevin RC, Luo JL, Crowther MS, McGregor IS. Parameters That Affect Fear Responses in Rodents and How to Use Them for Management. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00136] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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9
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Abstract
The effect of sound on the behaviour of sharks has not been investigated since the 1970s. Sound is, however, an important sensory stimulus underwater, as it can spread in all directions quickly and propagate further than any other sensory cue. We used a baited underwater camera rig to record the behavioural responses of eight species of sharks (seven reef and coastal shark species and the white shark, Carcharodon carcharias) to the playback of two distinct sound stimuli in the wild: an orca call sequence and an artificially generated sound. When sounds were playing, reef and coastal sharks were less numerous in the area, were responsible for fewer interactions with the baited test rigs, and displayed less ‘inquisitive’ behaviour, compared to during silent control trials. White sharks spent less time around the baited camera rig when the artificial sound was presented, but showed no significant difference in behaviour in response to orca calls. The use of the presented acoustic stimuli alone is not an effective deterrent for C. carcharias. The behavioural response of reef sharks to sound raises concern about the effects of anthropogenic noise on these taxa.
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10
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Mikkelsen L, Hermannsen L, Beedholm K, Madsen PT, Tougaard J. Simulated seal scarer sounds scare porpoises, but not seals: species-specific responses to 12 kHz deterrence sounds. ROYAL SOCIETY OPEN SCIENCE 2017; 4:170286. [PMID: 28791155 PMCID: PMC5541550 DOI: 10.1098/rsos.170286] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 06/19/2017] [Indexed: 06/07/2023]
Abstract
Acoustic harassment devices (AHD) or 'seal scarers' are used extensively, not only to deter seals from fisheries, but also as mitigation tools to deter marine mammals from potentially harmful sound sources, such as offshore pile driving. To test the effectiveness of AHDs, we conducted two studies with similar experimental set-ups on two key species: harbour porpoises and harbour seals. We exposed animals to 500 ms tone bursts at 12 kHz simulating that of an AHD (Lofitech), but with reduced output levels (source peak-to-peak level of 165 dB re 1 µPa). Animals were localized with a theodolite before, during and after sound exposures. In total, 12 sound exposures were conducted to porpoises and 13 exposures to seals. Porpoises were found to exhibit avoidance reactions out to ranges of 525 m from the sound source. Contrary to this, seal observations increased during sound exposure within 100 m of the loudspeaker. We thereby demonstrate that porpoises and seals respond very differently to AHD sounds. This has important implications for application of AHDs in multi-species habitats, as sound levels required to deter less sensitive species (seals) can lead to excessive and unwanted large deterrence ranges on more sensitive species (porpoises).
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Affiliation(s)
| | - Line Hermannsen
- Department of Bioscience, Aarhus University, Roskilde, Denmark
- Zoophysiology, Department of Bioscience, Aarhus University, Aarhus, Denmark
| | - Kristian Beedholm
- Zoophysiology, Department of Bioscience, Aarhus University, Aarhus, Denmark
| | | | - Jakob Tougaard
- Department of Bioscience, Aarhus University, Roskilde, Denmark
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11
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Parsons MH, Apfelbach R, Banks PB, Cameron EZ, Dickman CR, Frank ASK, Jones ME, McGregor IS, McLean S, Müller-Schwarze D, Sparrow EE, Blumstein DT. Biologically meaningful scents: a framework for understanding predator-prey research across disciplines. Biol Rev Camb Philos Soc 2017; 93:98-114. [DOI: 10.1111/brv.12334] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 03/17/2017] [Accepted: 03/21/2017] [Indexed: 12/17/2022]
Affiliation(s)
- Michael H. Parsons
- Department of Biology; Hofstra University; Hempstead NY 11549 U.S.A
- Department of Biological Sciences; Fordham University; Bronx NY 10458 U.S.A
| | - Raimund Apfelbach
- Institut für Neurobiologie; Universität Tübingen; Tübingen 72076 Germany
| | - Peter B. Banks
- School of Life and Environmental Sciences; The University of Sydney; Camperdown 2006 Australia
| | - Elissa Z. Cameron
- School of Biological Sciences; University of Tasmania; Hobart TAS 7001 Australia
| | - Chris R. Dickman
- Desert Ecology Research Group, School of Life and Environmental Sciences; The University of Sydney; Camperdown 2006 Australia
| | - Anke S. K. Frank
- School of Biological Sciences; University of Tasmania; Hobart TAS 7001 Australia
- Botanisches Institut, AG Linstädter; Universität zu Köln; D-50674 Köln Germany
| | - Menna E. Jones
- School of Biological Sciences; University of Tasmania; Hobart TAS 7001 Australia
| | - Ian S. McGregor
- School of Psychology, Brain and Mind Centre; University of Sydney; Camperdown 2050 Australia
| | - Stuart McLean
- School of Medicine; University of Tasmania; Hobart TAS 7001 Australia
| | - Dietland Müller-Schwarze
- College of Environmental Science and Forestry; State University of New York; Syracuse NY 13210 U.S.A
| | - Elisa E. Sparrow
- Department of Environment, Water and Natural Resources; Natural Resources Adelaide and Mt Lofty Ranges; Willunga 5172 Australia
| | - Daniel T. Blumstein
- Department of Ecology and Evolutionary Biology; University of California; Los Angeles CA 90095-1606 U.S.A
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12
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van den Hoff J, Kilpatrick R, Welsford D. Southern elephant seals (Mirounga leonina Linn.) depredate toothfish longlines in the midnight zone. PLoS One 2017; 12:e0172396. [PMID: 28234988 PMCID: PMC5325274 DOI: 10.1371/journal.pone.0172396] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 02/03/2017] [Indexed: 11/19/2022] Open
Abstract
Humans have devised fishing technologies that compete with marine predators for fish resources world-wide. One such fishery for the Patagonian toothfish (Dissostichus eleginoides) has developed interactions with a range of predators, some of which are marine mammals capable of diving to extreme depths for extended periods. A deep-sea camera system deployed within a toothfish fishery operating in the Southern Ocean acquired the first-ever video footage of an extreme-diver, the southern elephant seal (Mirounga leonina), depredating catch from longlines set at depths in excess of 1000m. The interactions recorded were non-lethal, however independent fisheries observer reports confirm elephant seal-longline interactions can be lethal. The seals behaviour of depredating catch at depth during the line soak-period differs to other surface-breathing species and thus presents a unique challenge to mitigate their by-catch. Deployments of deep-sea cameras on exploratory fishing gear prior to licencing and permit approvals would gather valuable information regarding the nature of interactions between deep diving/dwelling marine species and longline fisheries operating at bathypelagic depths. Furthermore, the positive identification by sex and age class of species interacting with commercial fisheries would assist in formulating management plans and mitigation strategies founded on species-specific life-history strategies.
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Affiliation(s)
- John van den Hoff
- Australian Antarctic Division, Kingston, Tasmania, Australia
- * E-mail:
| | | | - Dirk Welsford
- Australian Antarctic Division, Kingston, Tasmania, Australia
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13
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Schakner ZA, Götz T, Janik VM, Blumstein DT. Can fear conditioning repel California sea lions from fishing activities? Anim Conserv 2017. [DOI: 10.1111/acv.12329] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Zachary A. Schakner
- Department of Ecology & Evolutionary Biology University of California Los Angeles Los Angeles CA 90095‐1606 USA
| | - Thomas Götz
- Sea Mammal Research Unit Scottish Oceans Institute University of St Andrews East Sands St Andrews Fife KY16 8LB UK
| | - Vincent M. Janik
- Sea Mammal Research Unit Scottish Oceans Institute University of St Andrews East Sands St Andrews Fife KY16 8LB UK
| | - Daniel T. Blumstein
- Department of Ecology & Evolutionary Biology University of California Los Angeles Los Angeles CA 90095‐1606 USA
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14
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Taxonomy of Means and Ends in Aquaculture Production—Part 1: The Functions. WATER 2016. [DOI: 10.3390/w8080319] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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15
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Götz T, Janik VM. The startle reflex in acoustic deterrence: an approach with universal applicability? Anim Conserv 2016. [DOI: 10.1111/acv.12295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- T. Götz
- Sea Mammal Research Unit; Scottish Oceans Institute; University of St Andrews; St Andrews UK
| | - V. M. Janik
- Sea Mammal Research Unit; Scottish Oceans Institute; University of St Andrews; St Andrews UK
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16
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Trites AW, Spitz J. One-two punches to eliminate depredation by marine mammals on fish caught or raised for human consumption. Anim Conserv 2016. [DOI: 10.1111/acv.12291] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- A. W. Trites
- Marine Mammal Research Unit; Institute for the Oceans and Fisheries; University of British Columbia; Vancouver BC Canada
| | - J. Spitz
- Observatoire PELAGIS, UMS 3462; Université de La Rochelle/CNRS; La Rochelle France
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17
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Götz T, Janik VM. Non-lethal management of carnivore predation: long-term tests with a startle reflex-based deterrence system on a fish farm. Anim Conserv 2016. [DOI: 10.1111/acv.12248] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- T. Götz
- Sea Mammal Research Unit; Scottish Oceans Institute; University of St Andrews; St Andrews Scotland UK
| | - V. M. Janik
- Sea Mammal Research Unit; Scottish Oceans Institute; University of St Andrews; St Andrews Scotland UK
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