Spatial Dynamics of Harbour Porpoise Phocoena phocoena Relative to Local Hydrodynamics and Environmental Conditions

Runya  Robert; C McGonigle; Rory Quinn; Morgane Pommier; Christian Armstrong

doi:10.1002/ece3.71334

Spatial Dynamics of Harbour Porpoise Phocoena phocoena Relative to Local Hydrodynamics and Environmental Conditions

Runya Robert
, C McGonigle
, Rory Quinn
, Morgane Pommier
, Christian Armstrong

Research output: Contribution to journal › Article › peer-review

31 Downloads (Pure)

Abstract

Understanding the spatial dynamics of harbour porpoise (Phocoena phocoena) is crucial for effective conservation and management. The study presents a multidisciplinary approach to modelling and analysing the site occurrence and habitat use of Phocoena phocoena within the Skerries and Causeway Special Area of Conservation (SAC), identifying areas where they were seen surfacing and/or spending the most time. Using data derived from multibeam echosounders (MBES), particle size analysis of sediments, hydrodynamic modelling, and theodolite tracking observations, the study examines the influence of local hydrodynamics and environmental conditions on the spatial distribution of harbour porpoises. Kernel density analysis of 451 porpoise sightings over an 11-day survey demonstrated that dense clusters and higher aggregations occurred within ~500 m of the shoreline. Generalised Additive Models (GAMs) identified slope, aspect, backscatter intensity and sediment grain size as the most significant environmental predictors, accounting for 47.6% of the deviance in harbour porpoise distribution. Porpoises' occurrence was particularly spatially coincident with coarser sediments (4.25–5 mm), and their distribution was highly concentrated around headlands, shoreline and within a 3-h window before and after high water. Overall, these findings highlight the dynamic nature of harbour porpoises' use of habitat in space and time, with models predicting a high probability of porpoise encounters (> 0.6) nearshore, particularly in headland areas characterised by local flow acceleration and coarser seabeds. The study presents a robust workflow for developing a porpoise-specific monitoring program. By leveraging multidisciplinary methodological approaches, the study provides a scientific basis for refining marine conservation measures, delivering long-term protection for harbour porpoise habitats under existing legal and management frameworks both within and beyond the SAC boundaries.

Original language	English
Article number	e71334
Pages (from-to)	1-19
Number of pages	19
Journal	Ecology and Evolution
Volume	15
Issue number	5
Early online date	7 May 2025
DOIs	https://doi.org/10.1002/ece3.71334
Publication status	Published (in print/issue) - 31 May 2025

Bibliographical note

Publisher Copyright:
© 2025 The Author(s). Ecology and Evolution published by British Ecological Society and John Wiley & Sons Ltd.

Data Availability Statement

The multibeam data and particle size analysis sediment data used is pub-licly available on https://experience.arcgis.com/experience/3f2815e-c89e745d2b65630429d06385c and https://data.marine.ie/geonetwork/srv/eng/catalog.search#/metadata/ie.marine.data:dataset.5029, respec-tively. Meanwhile, the tidal data are available upon request at https://w w w.bodc.ac.uk/data/hosted_data_systems/sea_level/uk_tide_gauge_network/#time_series. Additionally, Data S1 has been provided comprising the field tracking observations of harbour porpoise's speciesPhocoena phocoena.

Funding

This research was funded by the Marine Institute (MI) under the Marine Research Programme by the Irish Government Cruises JIBS survey.Staffing was supported through the Marine Protected Area Monitoring and Management (MarPAMM) and SeaMonitor projects, which are supported by theEuropean Union's INTERREG VA Programme, managed by the Special EU Programmes Body (SEUPB) with matching funding from the Government ofIreland, the Northern Ireland Executive and the Scottish Government. This work was also carried out as part of Robert's PhD research funded through theVice Chancellor Research Scholarship of Ulster University (UK)

Funders
Scottish Government
Northern Ireland Executive
Agri-Food and Biosciences Institute
Government of Ireland
Marine Institute
Scottish Association for Marine Science
SEUPB

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

SDG 13 Climate Action
SDG 14 Life Below Water

Keywords

conservation
habitat use
harbour porpoises
hydrodynamic
remote sensing
species distribution models

Access to Document

10.1002/ece3.71334

Ecology and Evolution - 2025 - Runya - Spatial Dynamics of Harbour Porpoise Phocoena phocoena Relative to LocalFinal published version, 7.83 MBLicence: CC BY

Cite this

@article{858d240283024540a27f29d3b3bad83e,

title = "Spatial Dynamics of Harbour Porpoise Phocoena phocoena Relative to Local Hydrodynamics and Environmental Conditions",

abstract = "Understanding the spatial dynamics of harbour porpoise (Phocoena phocoena) is crucial for effective conservation and management. The study presents a multidisciplinary approach to modelling and analysing the site occurrence and habitat use of Phocoena phocoena within the Skerries and Causeway Special Area of Conservation (SAC), identifying areas where they were seen surfacing and/or spending the most time. Using data derived from multibeam echosounders (MBES), particle size analysis of sediments, hydrodynamic modelling, and theodolite tracking observations, the study examines the influence of local hydrodynamics and environmental conditions on the spatial distribution of harbour porpoises. Kernel density analysis of 451 porpoise sightings over an 11-day survey demonstrated that dense clusters and higher aggregations occurred within \textasciitilde{}500 m of the shoreline. Generalised Additive Models (GAMs) identified slope, aspect, backscatter intensity and sediment grain size as the most significant environmental predictors, accounting for 47.6\% of the deviance in harbour porpoise distribution. Porpoises' occurrence was particularly spatially coincident with coarser sediments (4.25–5 mm), and their distribution was highly concentrated around headlands, shoreline and within a 3-h window before and after high water. Overall, these findings highlight the dynamic nature of harbour porpoises' use of habitat in space and time, with models predicting a high probability of porpoise encounters (> 0.6) nearshore, particularly in headland areas characterised by local flow acceleration and coarser seabeds. The study presents a robust workflow for developing a porpoise-specific monitoring program. By leveraging multidisciplinary methodological approaches, the study provides a scientific basis for refining marine conservation measures, delivering long-term protection for harbour porpoise habitats under existing legal and management frameworks both within and beyond the SAC boundaries.",

keywords = "conservation, habitat use, harbour porpoises, hydrodynamic, remote sensing, species distribution models",

author = "Runya Robert and C McGonigle and Rory Quinn and Morgane Pommier and Christian Armstrong",

note = "Publisher Copyright: {\textcopyright} 2025 The Author(s). Ecology and Evolution published by British Ecological Society and John Wiley \& Sons Ltd.",

year = "2025",

month = may,

day = "31",

doi = "10.1002/ece3.71334",

language = "English",

volume = "15",

pages = "1--19",

journal = "Ecology and Evolution",

issn = "2045-7758",

publisher = "John Wiley \& Sons, Inc.",

number = "5",

}

TY - JOUR

T1 - Spatial Dynamics of Harbour Porpoise Phocoena phocoena Relative to Local Hydrodynamics and Environmental Conditions

AU - Robert, Runya

AU - McGonigle, C

AU - Quinn, Rory

AU - Pommier, Morgane

AU - Armstrong, Christian

PY - 2025/5/31

Y1 - 2025/5/31

N2 - Understanding the spatial dynamics of harbour porpoise (Phocoena phocoena) is crucial for effective conservation and management. The study presents a multidisciplinary approach to modelling and analysing the site occurrence and habitat use of Phocoena phocoena within the Skerries and Causeway Special Area of Conservation (SAC), identifying areas where they were seen surfacing and/or spending the most time. Using data derived from multibeam echosounders (MBES), particle size analysis of sediments, hydrodynamic modelling, and theodolite tracking observations, the study examines the influence of local hydrodynamics and environmental conditions on the spatial distribution of harbour porpoises. Kernel density analysis of 451 porpoise sightings over an 11-day survey demonstrated that dense clusters and higher aggregations occurred within ~500 m of the shoreline. Generalised Additive Models (GAMs) identified slope, aspect, backscatter intensity and sediment grain size as the most significant environmental predictors, accounting for 47.6% of the deviance in harbour porpoise distribution. Porpoises' occurrence was particularly spatially coincident with coarser sediments (4.25–5 mm), and their distribution was highly concentrated around headlands, shoreline and within a 3-h window before and after high water. Overall, these findings highlight the dynamic nature of harbour porpoises' use of habitat in space and time, with models predicting a high probability of porpoise encounters (> 0.6) nearshore, particularly in headland areas characterised by local flow acceleration and coarser seabeds. The study presents a robust workflow for developing a porpoise-specific monitoring program. By leveraging multidisciplinary methodological approaches, the study provides a scientific basis for refining marine conservation measures, delivering long-term protection for harbour porpoise habitats under existing legal and management frameworks both within and beyond the SAC boundaries.

AB - Understanding the spatial dynamics of harbour porpoise (Phocoena phocoena) is crucial for effective conservation and management. The study presents a multidisciplinary approach to modelling and analysing the site occurrence and habitat use of Phocoena phocoena within the Skerries and Causeway Special Area of Conservation (SAC), identifying areas where they were seen surfacing and/or spending the most time. Using data derived from multibeam echosounders (MBES), particle size analysis of sediments, hydrodynamic modelling, and theodolite tracking observations, the study examines the influence of local hydrodynamics and environmental conditions on the spatial distribution of harbour porpoises. Kernel density analysis of 451 porpoise sightings over an 11-day survey demonstrated that dense clusters and higher aggregations occurred within ~500 m of the shoreline. Generalised Additive Models (GAMs) identified slope, aspect, backscatter intensity and sediment grain size as the most significant environmental predictors, accounting for 47.6% of the deviance in harbour porpoise distribution. Porpoises' occurrence was particularly spatially coincident with coarser sediments (4.25–5 mm), and their distribution was highly concentrated around headlands, shoreline and within a 3-h window before and after high water. Overall, these findings highlight the dynamic nature of harbour porpoises' use of habitat in space and time, with models predicting a high probability of porpoise encounters (> 0.6) nearshore, particularly in headland areas characterised by local flow acceleration and coarser seabeds. The study presents a robust workflow for developing a porpoise-specific monitoring program. By leveraging multidisciplinary methodological approaches, the study provides a scientific basis for refining marine conservation measures, delivering long-term protection for harbour porpoise habitats under existing legal and management frameworks both within and beyond the SAC boundaries.

KW - conservation

KW - habitat use

KW - harbour porpoises

KW - hydrodynamic

KW - remote sensing

KW - species distribution models

UR - https://www.scopus.com/pages/publications/105004689227

U2 - 10.1002/ece3.71334

DO - 10.1002/ece3.71334

M3 - Article

C2 - 40342696

SN - 2045-7758

VL - 15

SP - 1

EP - 19

JO - Ecology and Evolution

JF - Ecology and Evolution

IS - 5

M1 - e71334

ER -

Spatial Dynamics of Harbour Porpoise Phocoena phocoena Relative to Local Hydrodynamics and Environmental Conditions

Abstract

Bibliographical note

Data Availability Statement

Funding

UN SDGs

Keywords

Access to Document

Other files and links

Fingerprint

Cite this