E-Thesis 18 views 2 downloads
The demographic role and drivers of crash mortality in nesting seabirds / STEFAN BARNETT
Swansea University Author: STEFAN BARNETT
Abstract
Recent research suggests that animals adjust their space-use to minimise their chance of accidents, such as slips or collisions. The consequences of such accidents should be particularly severe in flying animals, but examples of collisions in natural scenarios remain rare. Regular crashes have been d...
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Swansea
2026
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| Institution: | Swansea University |
| Degree level: | Master of Research |
| Degree name: | MRes |
| Supervisor: | Bull, J., and Shepard, E. |
| URI: | https://cronfa.swan.ac.uk/Record/cronfa71897 |
| first_indexed |
2026-05-14T13:01:38Z |
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| last_indexed |
2026-05-15T05:41:59Z |
| id |
cronfa71897 |
| recordtype |
RisThesis |
| fullrecord |
<?xml version="1.0"?><rfc1807><datestamp>2026-05-14T14:01:36.4731449</datestamp><bib-version>v2</bib-version><id>71897</id><entry>2026-05-14</entry><title>The demographic role and drivers of crash mortality in nesting seabirds</title><swanseaauthors><author><sid>643ef2d570b52381c25f8a4f50147b30</sid><firstname>STEFAN</firstname><surname>BARNETT</surname><name>STEFAN BARNETT</name><active>true</active><ethesisStudent>false</ethesisStudent></author></swanseaauthors><date>2026-05-14</date><abstract>Recent research suggests that animals adjust their space-use to minimise their chance of accidents, such as slips or collisions. The consequences of such accidents should be particularly severe in flying animals, but examples of collisions in natural scenarios remain rare. Regular crashes have been documented in a population of northern gannets breeding on Ailsa Craig. In this study I use a dataset of crashes recorded each month over three consecutive years, along with reanalysis data, to investigate the environmental drivers of gannet crashes and assess their demographic consequences. I combined statistical and demographic approaches to address three questions: (1) can environmental factors predict crash events, (2) what are the consequences of crash mortality for population growth rates, and (3) how might shifting wind regimes influence long-term population trajectories? Quasibinomial generalized linear models were used to test environmental predictors of crash events, while matrix population models were used to project population dynamics. Outputs from statistical models were integrated into matrix population models by adjusting adult survival transitions. Wind direction emerged as the sole significant predictor of crashes, with the probability of crashes increasing in north-westerly winds and decreasing with south-easterlies. Crash mortality accounted for 5.4% of annual adult mortality. Removing this mortality led to increases in projected population sizes of 11.3% and 23.9% over 25 and 50 years, respectively.Incorporating wind-driven crash probabilities into demographic models revealed the full envelope of population responses that would be possible under changing wind regimes.These findings identify accident mortality as a novel, demographic, non-anthropogenic pressure in a long-lived seabird. Shifting wind regimes may influence seabird populations by altering habitat suitability and modifying the landscape of risk around colonies, thereby broadening our understanding of how environmental variability shapes avian population dynamics.</abstract><type>E-Thesis</type><journal/><volume/><journalNumber/><paginationStart/><paginationEnd/><publisher/><placeOfPublication>Swansea</placeOfPublication><isbnPrint/><isbnElectronic/><issnPrint/><issnElectronic/><keywords>Professor James Bull, Professor Emily Shepard</keywords><publishedDay>3</publishedDay><publishedMonth>3</publishedMonth><publishedYear>2026</publishedYear><publishedDate>2026-03-03</publishedDate><doi/><url/><notes/><college>COLLEGE NANME</college><CollegeCode>COLLEGE CODE</CollegeCode><institution>Swansea University</institution><supervisor>Bull, J., and Shepard, E.</supervisor><degreelevel>Master of Research</degreelevel><degreename>MRes</degreename><apcterm/><funders/><projectreference/><lastEdited>2026-05-14T14:01:36.4731449</lastEdited><Created>2026-05-14T13:50:31.2924384</Created><path><level id="1">Faculty of Science and Engineering</level><level id="2">School of Biosciences, Geography and Physics - Biosciences</level></path><authors><author><firstname>STEFAN</firstname><surname>BARNETT</surname><order>1</order></author></authors><documents><document><filename>71897__36729__077b6dd025d44fce91de5cd1e27a1ad0.pdf</filename><originalFilename>2026_Barnett_S.final.71897.pdf</originalFilename><uploaded>2026-05-14T14:01:00.7509921</uploaded><type>Output</type><contentLength>1387466</contentLength><contentType>application/pdf</contentType><version>E-Thesis – open access</version><cronfaStatus>true</cronfaStatus><documentNotes>Copyright: the author, Stefan Barnett, 2026</documentNotes><copyrightCorrect>true</copyrightCorrect><language>eng</language></document></documents><OutputDurs/></rfc1807> |
| spelling |
2026-05-14T14:01:36.4731449 v2 71897 2026-05-14 The demographic role and drivers of crash mortality in nesting seabirds 643ef2d570b52381c25f8a4f50147b30 STEFAN BARNETT STEFAN BARNETT true false 2026-05-14 Recent research suggests that animals adjust their space-use to minimise their chance of accidents, such as slips or collisions. The consequences of such accidents should be particularly severe in flying animals, but examples of collisions in natural scenarios remain rare. Regular crashes have been documented in a population of northern gannets breeding on Ailsa Craig. In this study I use a dataset of crashes recorded each month over three consecutive years, along with reanalysis data, to investigate the environmental drivers of gannet crashes and assess their demographic consequences. I combined statistical and demographic approaches to address three questions: (1) can environmental factors predict crash events, (2) what are the consequences of crash mortality for population growth rates, and (3) how might shifting wind regimes influence long-term population trajectories? Quasibinomial generalized linear models were used to test environmental predictors of crash events, while matrix population models were used to project population dynamics. Outputs from statistical models were integrated into matrix population models by adjusting adult survival transitions. Wind direction emerged as the sole significant predictor of crashes, with the probability of crashes increasing in north-westerly winds and decreasing with south-easterlies. Crash mortality accounted for 5.4% of annual adult mortality. Removing this mortality led to increases in projected population sizes of 11.3% and 23.9% over 25 and 50 years, respectively.Incorporating wind-driven crash probabilities into demographic models revealed the full envelope of population responses that would be possible under changing wind regimes.These findings identify accident mortality as a novel, demographic, non-anthropogenic pressure in a long-lived seabird. Shifting wind regimes may influence seabird populations by altering habitat suitability and modifying the landscape of risk around colonies, thereby broadening our understanding of how environmental variability shapes avian population dynamics. E-Thesis Swansea Professor James Bull, Professor Emily Shepard 3 3 2026 2026-03-03 COLLEGE NANME COLLEGE CODE Swansea University Bull, J., and Shepard, E. Master of Research MRes 2026-05-14T14:01:36.4731449 2026-05-14T13:50:31.2924384 Faculty of Science and Engineering School of Biosciences, Geography and Physics - Biosciences STEFAN BARNETT 1 71897__36729__077b6dd025d44fce91de5cd1e27a1ad0.pdf 2026_Barnett_S.final.71897.pdf 2026-05-14T14:01:00.7509921 Output 1387466 application/pdf E-Thesis – open access true Copyright: the author, Stefan Barnett, 2026 true eng |
| title |
The demographic role and drivers of crash mortality in nesting seabirds |
| spellingShingle |
The demographic role and drivers of crash mortality in nesting seabirds STEFAN BARNETT |
| title_short |
The demographic role and drivers of crash mortality in nesting seabirds |
| title_full |
The demographic role and drivers of crash mortality in nesting seabirds |
| title_fullStr |
The demographic role and drivers of crash mortality in nesting seabirds |
| title_full_unstemmed |
The demographic role and drivers of crash mortality in nesting seabirds |
| title_sort |
The demographic role and drivers of crash mortality in nesting seabirds |
| author_id_str_mv |
643ef2d570b52381c25f8a4f50147b30 |
| author_id_fullname_str_mv |
643ef2d570b52381c25f8a4f50147b30_***_STEFAN BARNETT |
| author |
STEFAN BARNETT |
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STEFAN BARNETT |
| format |
E-Thesis |
| publishDate |
2026 |
| institution |
Swansea University |
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Faculty of Science and Engineering |
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|
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facultyofscienceandengineering |
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Faculty of Science and Engineering |
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facultyofscienceandengineering |
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Faculty of Science and Engineering |
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School of Biosciences, Geography and Physics - Biosciences{{{_:::_}}}Faculty of Science and Engineering{{{_:::_}}}School of Biosciences, Geography and Physics - Biosciences |
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| description |
Recent research suggests that animals adjust their space-use to minimise their chance of accidents, such as slips or collisions. The consequences of such accidents should be particularly severe in flying animals, but examples of collisions in natural scenarios remain rare. Regular crashes have been documented in a population of northern gannets breeding on Ailsa Craig. In this study I use a dataset of crashes recorded each month over three consecutive years, along with reanalysis data, to investigate the environmental drivers of gannet crashes and assess their demographic consequences. I combined statistical and demographic approaches to address three questions: (1) can environmental factors predict crash events, (2) what are the consequences of crash mortality for population growth rates, and (3) how might shifting wind regimes influence long-term population trajectories? Quasibinomial generalized linear models were used to test environmental predictors of crash events, while matrix population models were used to project population dynamics. Outputs from statistical models were integrated into matrix population models by adjusting adult survival transitions. Wind direction emerged as the sole significant predictor of crashes, with the probability of crashes increasing in north-westerly winds and decreasing with south-easterlies. Crash mortality accounted for 5.4% of annual adult mortality. Removing this mortality led to increases in projected population sizes of 11.3% and 23.9% over 25 and 50 years, respectively.Incorporating wind-driven crash probabilities into demographic models revealed the full envelope of population responses that would be possible under changing wind regimes.These findings identify accident mortality as a novel, demographic, non-anthropogenic pressure in a long-lived seabird. Shifting wind regimes may influence seabird populations by altering habitat suitability and modifying the landscape of risk around colonies, thereby broadening our understanding of how environmental variability shapes avian population dynamics. |
| published_date |
2026-03-03T06:41:59Z |
| _version_ |
1865231860029718528 |
| score |
11.106 |