The effects of marine traffic on the behaviour of Black Sea harbour porpoises (Phocoena phocoena relicta) within the Istanbul Strait, Turkey
Marine traffic is threatening cetaceans on a local and global scale. The Istanbul Strait is one of the busiest waterways, with up to 2,500 vessels present daily. This is the first study to assess the magnitude of short- and long-term behavioural changes of the endangered Black Sea harbour porpoises...
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ftpubmed:oai:pubmedcentral.nih.gov:5351841 2023-05-15T17:59:10+02:00 The effects of marine traffic on the behaviour of Black Sea harbour porpoises (Phocoena phocoena relicta) within the Istanbul Strait, Turkey Akkaya Bas, Aylin Christiansen, Fredrik Amaha Öztürk, Ayaka Öztürk, Bayram McIntosh, Caley 2017-03-15 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5351841/ http://www.ncbi.nlm.nih.gov/pubmed/28296899 https://doi.org/10.1371/journal.pone.0172970 en eng Public Library of Science http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5351841/ http://www.ncbi.nlm.nih.gov/pubmed/28296899 http://dx.doi.org/10.1371/journal.pone.0172970 © 2017 Akkaya Bas et al http://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. CC-BY Research Article Text 2017 ftpubmed https://doi.org/10.1371/journal.pone.0172970 2017-04-09T00:02:05Z Marine traffic is threatening cetaceans on a local and global scale. The Istanbul Strait is one of the busiest waterways, with up to 2,500 vessels present daily. This is the first study to assess the magnitude of short- and long-term behavioural changes of the endangered Black Sea harbour porpoises (Phocoena phocoena relicta) in the presence of marine vessels within the Istanbul Strait. Markov chains were used to investigate the effect of vessel presence on the transition probability between behavioural states (diving, surface-feeding and travelling), and to quantify the effect on the behavioural budget and bout length (duration of time spent in a given state) of porpoises. Further, the changes on swimming directions of porpoises in relation to vessel speed and distance was investigated using generalized linear models. In vessel presence, porpoises were less likely to remain in a given behavioural state and instead more likely to switch to another state. Because of this, the bout length of all three behavioural states decreased significantly in the presence of vessels. The vessel effect was sufficiently large to alter the behavioural budget, with surface-feeding decreasing significantly in the presence of vessels. However, when taking into account the proportion of time that porpoises were exposed to vessels (i.e. 50%), the measured effect size was not large enough to significantly alter the animals’ cumulative (diurnal) behavioural budget. Additionally, vessel speed and distance had a significant effect on the probability of porpoises showing a response in their swimming directions. The southern and middle sections of the Istanbul Strait, which have the heaviest marine traffic pressure, had the lowest porpoise sightings throughout the year. Conversely, northern sections that were exposed to a lesser degree of marine traffic hold the highest porpoise sightings. The effect shown in this study in combination with increasing human impacts within the northern sections should be considered carefully and ... Text Phocoena phocoena PubMed Central (PMC) PLOS ONE 12 3 e0172970 |
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Research Article Akkaya Bas, Aylin Christiansen, Fredrik Amaha Öztürk, Ayaka Öztürk, Bayram McIntosh, Caley The effects of marine traffic on the behaviour of Black Sea harbour porpoises (Phocoena phocoena relicta) within the Istanbul Strait, Turkey |
topic_facet |
Research Article |
description |
Marine traffic is threatening cetaceans on a local and global scale. The Istanbul Strait is one of the busiest waterways, with up to 2,500 vessels present daily. This is the first study to assess the magnitude of short- and long-term behavioural changes of the endangered Black Sea harbour porpoises (Phocoena phocoena relicta) in the presence of marine vessels within the Istanbul Strait. Markov chains were used to investigate the effect of vessel presence on the transition probability between behavioural states (diving, surface-feeding and travelling), and to quantify the effect on the behavioural budget and bout length (duration of time spent in a given state) of porpoises. Further, the changes on swimming directions of porpoises in relation to vessel speed and distance was investigated using generalized linear models. In vessel presence, porpoises were less likely to remain in a given behavioural state and instead more likely to switch to another state. Because of this, the bout length of all three behavioural states decreased significantly in the presence of vessels. The vessel effect was sufficiently large to alter the behavioural budget, with surface-feeding decreasing significantly in the presence of vessels. However, when taking into account the proportion of time that porpoises were exposed to vessels (i.e. 50%), the measured effect size was not large enough to significantly alter the animals’ cumulative (diurnal) behavioural budget. Additionally, vessel speed and distance had a significant effect on the probability of porpoises showing a response in their swimming directions. The southern and middle sections of the Istanbul Strait, which have the heaviest marine traffic pressure, had the lowest porpoise sightings throughout the year. Conversely, northern sections that were exposed to a lesser degree of marine traffic hold the highest porpoise sightings. The effect shown in this study in combination with increasing human impacts within the northern sections should be considered carefully and ... |
format |
Text |
author |
Akkaya Bas, Aylin Christiansen, Fredrik Amaha Öztürk, Ayaka Öztürk, Bayram McIntosh, Caley |
author_facet |
Akkaya Bas, Aylin Christiansen, Fredrik Amaha Öztürk, Ayaka Öztürk, Bayram McIntosh, Caley |
author_sort |
Akkaya Bas, Aylin |
title |
The effects of marine traffic on the behaviour of Black Sea harbour porpoises (Phocoena phocoena relicta) within the Istanbul Strait, Turkey |
title_short |
The effects of marine traffic on the behaviour of Black Sea harbour porpoises (Phocoena phocoena relicta) within the Istanbul Strait, Turkey |
title_full |
The effects of marine traffic on the behaviour of Black Sea harbour porpoises (Phocoena phocoena relicta) within the Istanbul Strait, Turkey |
title_fullStr |
The effects of marine traffic on the behaviour of Black Sea harbour porpoises (Phocoena phocoena relicta) within the Istanbul Strait, Turkey |
title_full_unstemmed |
The effects of marine traffic on the behaviour of Black Sea harbour porpoises (Phocoena phocoena relicta) within the Istanbul Strait, Turkey |
title_sort |
effects of marine traffic on the behaviour of black sea harbour porpoises (phocoena phocoena relicta) within the istanbul strait, turkey |
publisher |
Public Library of Science |
publishDate |
2017 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5351841/ http://www.ncbi.nlm.nih.gov/pubmed/28296899 https://doi.org/10.1371/journal.pone.0172970 |
genre |
Phocoena phocoena |
genre_facet |
Phocoena phocoena |
op_relation |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5351841/ http://www.ncbi.nlm.nih.gov/pubmed/28296899 http://dx.doi.org/10.1371/journal.pone.0172970 |
op_rights |
© 2017 Akkaya Bas et al http://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. |
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CC-BY |
op_doi |
https://doi.org/10.1371/journal.pone.0172970 |
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PLOS ONE |
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12 |
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3 |
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e0172970 |
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