Stay close, but not too close: aerial image analysis reveals patterns of social distancing in seal colonies
Many species aggregate in dense colonies. Species-specific spatial patterns provide clues about how colonies are shaped by various (a)biotic factors, including predation, temperature regulation or disease transmission. Using aerial imagery, we examined these patterns in colonies on land of two sympa...
Published in: | Royal Society Open Science |
---|---|
Main Authors: | , , , , , |
Format: | Text |
Language: | unknown |
Published: |
2023
|
Subjects: | |
Online Access: | http://infoscience.epfl.ch/record/304035 https://doi.org/10.1098/rsos.230269 https://infoscience.epfl.ch/record/304035/files/rsos.230269.pdf |
id |
ftinfoscience:oai:infoscience.epfl.ch:304035 |
---|---|
record_format |
openpolar |
spelling |
ftinfoscience:oai:infoscience.epfl.ch:304035 2023-09-05T13:20:01+02:00 Stay close, but not too close: aerial image analysis reveals patterns of social distancing in seal colonies Hoekendijk, J. P. A. Grundlehner, A. Brasseur, S. Kellenberger, B. Tuia, Devis Aarts, G. 2023-08-09T13:44:57Z http://infoscience.epfl.ch/record/304035 https://doi.org/10.1098/rsos.230269 https://infoscience.epfl.ch/record/304035/files/rsos.230269.pdf unknown http://infoscience.epfl.ch/record/304035 doi:10.1098/rsos.230269 https://infoscience.epfl.ch/record/304035/files/rsos.230269.pdf http://infoscience.epfl.ch/record/304035 Text 2023 ftinfoscience https://doi.org/10.1098/rsos.230269 2023-08-13T23:46:59Z Many species aggregate in dense colonies. Species-specific spatial patterns provide clues about how colonies are shaped by various (a)biotic factors, including predation, temperature regulation or disease transmission. Using aerial imagery, we examined these patterns in colonies on land of two sympatric seal species: the harbour seal and grey seal. Results show that the density of grey seals on land is twice as high as that of harbour seals. Furthermore, the nearest neighbour distance (NND) of harbour seals (median = 1.06 m) is significantly larger than that of grey seals (median = 0.53 m). Avoidance at small distances (i.e. social distancing) was supported by spatial simulation: when the observed seal locations were shuffled slightly, the frequency of the smallest NNDs (0–25 cm) increased, while the most frequently observed NNDs decreased. As harbour seals are more prone to infectious diseases, we hypothesize that the larger NNDs might be a behavioural response to reduce pathogen transmission. The approach presented here can potentially be used as a practical tool to differentiate between harbour and grey seals in remote sensing applications, particularly in low to medium resolution imagery (e.g. satellite imagery), where morphological characteristics alone are insufficient to differentiate between species. Text harbour seal EPFL Infoscience (Ecole Polytechnique Fédérale Lausanne) Royal Society Open Science 10 8 |
institution |
Open Polar |
collection |
EPFL Infoscience (Ecole Polytechnique Fédérale Lausanne) |
op_collection_id |
ftinfoscience |
language |
unknown |
description |
Many species aggregate in dense colonies. Species-specific spatial patterns provide clues about how colonies are shaped by various (a)biotic factors, including predation, temperature regulation or disease transmission. Using aerial imagery, we examined these patterns in colonies on land of two sympatric seal species: the harbour seal and grey seal. Results show that the density of grey seals on land is twice as high as that of harbour seals. Furthermore, the nearest neighbour distance (NND) of harbour seals (median = 1.06 m) is significantly larger than that of grey seals (median = 0.53 m). Avoidance at small distances (i.e. social distancing) was supported by spatial simulation: when the observed seal locations were shuffled slightly, the frequency of the smallest NNDs (0–25 cm) increased, while the most frequently observed NNDs decreased. As harbour seals are more prone to infectious diseases, we hypothesize that the larger NNDs might be a behavioural response to reduce pathogen transmission. The approach presented here can potentially be used as a practical tool to differentiate between harbour and grey seals in remote sensing applications, particularly in low to medium resolution imagery (e.g. satellite imagery), where morphological characteristics alone are insufficient to differentiate between species. |
format |
Text |
author |
Hoekendijk, J. P. A. Grundlehner, A. Brasseur, S. Kellenberger, B. Tuia, Devis Aarts, G. |
spellingShingle |
Hoekendijk, J. P. A. Grundlehner, A. Brasseur, S. Kellenberger, B. Tuia, Devis Aarts, G. Stay close, but not too close: aerial image analysis reveals patterns of social distancing in seal colonies |
author_facet |
Hoekendijk, J. P. A. Grundlehner, A. Brasseur, S. Kellenberger, B. Tuia, Devis Aarts, G. |
author_sort |
Hoekendijk, J. P. A. |
title |
Stay close, but not too close: aerial image analysis reveals patterns of social distancing in seal colonies |
title_short |
Stay close, but not too close: aerial image analysis reveals patterns of social distancing in seal colonies |
title_full |
Stay close, but not too close: aerial image analysis reveals patterns of social distancing in seal colonies |
title_fullStr |
Stay close, but not too close: aerial image analysis reveals patterns of social distancing in seal colonies |
title_full_unstemmed |
Stay close, but not too close: aerial image analysis reveals patterns of social distancing in seal colonies |
title_sort |
stay close, but not too close: aerial image analysis reveals patterns of social distancing in seal colonies |
publishDate |
2023 |
url |
http://infoscience.epfl.ch/record/304035 https://doi.org/10.1098/rsos.230269 https://infoscience.epfl.ch/record/304035/files/rsos.230269.pdf |
genre |
harbour seal |
genre_facet |
harbour seal |
op_source |
http://infoscience.epfl.ch/record/304035 |
op_relation |
http://infoscience.epfl.ch/record/304035 doi:10.1098/rsos.230269 https://infoscience.epfl.ch/record/304035/files/rsos.230269.pdf |
op_doi |
https://doi.org/10.1098/rsos.230269 |
container_title |
Royal Society Open Science |
container_volume |
10 |
container_issue |
8 |
_version_ |
1776200771186982912 |