Reliability of VHF telemetry data for measuring attendance patterns of marine predators : a comparison with time depth recorder data
Very high frequency (VHF) radiotelemetry data has been used for over 30 yr to monitor the behavior patterns of otariid seals. These data have been used in a wide variety of ways, from characterizing the reproductive and foraging ecology of these species to inferring ecosystem changes based on variat...
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Online Access: | http://hdl.handle.net/2263/51757 https://doi.org/10.3354/meps11504 |
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ftunivpretoria:oai:repository.up.ac.za:2263/51757 2023-05-15T14:05:19+02:00 Reliability of VHF telemetry data for measuring attendance patterns of marine predators : a comparison with time depth recorder data Lowther, Andrew D. Ahonen, Heidi Hofmeyr, Greg Oosthuizen, Wessel Christiaan De Bruyn, P.J. Nico Lydersen, Christian Kovacs, Kit M. Corkeron, Peter 2016-03-09T11:11:44Z http://hdl.handle.net/2263/51757 https://doi.org/10.3354/meps11504 en eng Inter-Research http://hdl.handle.net/2263/51757 Lowther, AD, Ahonen, H, Hofmeyr, G, Oosthuizen, WC, De Bruyn, PJN, Lydersen, C & Kovacs, KM 2015, 'Reliability of VHF telemetry data for measuring attendance patterns of marine predators : a comparison with time depth recorder data', Marine Ecology-Progress Series, vol. 238, pp. 249-256. 0173-9565 (print) 1439-0485 (online) doi:10.3354/meps11504 © Inter-Research 2015 Otariid Ecosystem monitoring CCAMLR Telemetry Diving Attendance patterns Very high frequency (VHF) Time depth recorder (TDR) Article 2016 ftunivpretoria https://doi.org/10.3354/meps11504 2022-05-31T13:36:41Z Very high frequency (VHF) radiotelemetry data has been used for over 30 yr to monitor the behavior patterns of otariid seals. These data have been used in a wide variety of ways, from characterizing the reproductive and foraging ecology of these species to inferring ecosystem changes based on variation in attendance patterns. Yet the accuracy of VHF data has never been appropriately evaluated. Our study compares VHF data collected on 16 lactating Antarctic fur seals to assess onshore attendance with concurrently collected time depth recorder (TDR) data used as the ‘true’ measurement of time spent onshore. Within the retrieved datasets, 25% of the VHF data could not be interpreted with any reliability. Additionally, there were significant differences in the number and duration of attendance bouts between the 2 instrument types, with VHF data overestimating attendance bout duration by approximately 8.9 h on average. Importantly, the magnitude and direction of errors between VHF and TDR measurements were not systematic, suggesting that VHF data is an inappropriate method for collecting attendance data. Modelling the raw VHF data in a state-space framework elicited mean attendance durations that were indistinguishable from TDR-derived measurements, suggesting this approach may provide a means to re-examine historic VHF data. Moreover, given the evolution of electronic tags in terms of sophistication, miniaturization, longevity and decreasing cost over the last 30 yr, TDRs are a more appropriate means of collecting attendance data on centrally foraging marine mammals such as otariids. http://www.int-res.com/journals/meps/meps-home 2020-10-30 am2015 Article in Journal/Newspaper Antarc* Antarctic Antarctic Fur Seals University of Pretoria: UPSpace Antarctic Marine Ecology Progress Series 538 249 256 |
institution |
Open Polar |
collection |
University of Pretoria: UPSpace |
op_collection_id |
ftunivpretoria |
language |
English |
topic |
Otariid Ecosystem monitoring CCAMLR Telemetry Diving Attendance patterns Very high frequency (VHF) Time depth recorder (TDR) |
spellingShingle |
Otariid Ecosystem monitoring CCAMLR Telemetry Diving Attendance patterns Very high frequency (VHF) Time depth recorder (TDR) Lowther, Andrew D. Ahonen, Heidi Hofmeyr, Greg Oosthuizen, Wessel Christiaan De Bruyn, P.J. Nico Lydersen, Christian Kovacs, Kit M. Reliability of VHF telemetry data for measuring attendance patterns of marine predators : a comparison with time depth recorder data |
topic_facet |
Otariid Ecosystem monitoring CCAMLR Telemetry Diving Attendance patterns Very high frequency (VHF) Time depth recorder (TDR) |
description |
Very high frequency (VHF) radiotelemetry data has been used for over 30 yr to monitor the behavior patterns of otariid seals. These data have been used in a wide variety of ways, from characterizing the reproductive and foraging ecology of these species to inferring ecosystem changes based on variation in attendance patterns. Yet the accuracy of VHF data has never been appropriately evaluated. Our study compares VHF data collected on 16 lactating Antarctic fur seals to assess onshore attendance with concurrently collected time depth recorder (TDR) data used as the ‘true’ measurement of time spent onshore. Within the retrieved datasets, 25% of the VHF data could not be interpreted with any reliability. Additionally, there were significant differences in the number and duration of attendance bouts between the 2 instrument types, with VHF data overestimating attendance bout duration by approximately 8.9 h on average. Importantly, the magnitude and direction of errors between VHF and TDR measurements were not systematic, suggesting that VHF data is an inappropriate method for collecting attendance data. Modelling the raw VHF data in a state-space framework elicited mean attendance durations that were indistinguishable from TDR-derived measurements, suggesting this approach may provide a means to re-examine historic VHF data. Moreover, given the evolution of electronic tags in terms of sophistication, miniaturization, longevity and decreasing cost over the last 30 yr, TDRs are a more appropriate means of collecting attendance data on centrally foraging marine mammals such as otariids. http://www.int-res.com/journals/meps/meps-home 2020-10-30 am2015 |
author2 |
Corkeron, Peter |
format |
Article in Journal/Newspaper |
author |
Lowther, Andrew D. Ahonen, Heidi Hofmeyr, Greg Oosthuizen, Wessel Christiaan De Bruyn, P.J. Nico Lydersen, Christian Kovacs, Kit M. |
author_facet |
Lowther, Andrew D. Ahonen, Heidi Hofmeyr, Greg Oosthuizen, Wessel Christiaan De Bruyn, P.J. Nico Lydersen, Christian Kovacs, Kit M. |
author_sort |
Lowther, Andrew D. |
title |
Reliability of VHF telemetry data for measuring attendance patterns of marine predators : a comparison with time depth recorder data |
title_short |
Reliability of VHF telemetry data for measuring attendance patterns of marine predators : a comparison with time depth recorder data |
title_full |
Reliability of VHF telemetry data for measuring attendance patterns of marine predators : a comparison with time depth recorder data |
title_fullStr |
Reliability of VHF telemetry data for measuring attendance patterns of marine predators : a comparison with time depth recorder data |
title_full_unstemmed |
Reliability of VHF telemetry data for measuring attendance patterns of marine predators : a comparison with time depth recorder data |
title_sort |
reliability of vhf telemetry data for measuring attendance patterns of marine predators : a comparison with time depth recorder data |
publisher |
Inter-Research |
publishDate |
2016 |
url |
http://hdl.handle.net/2263/51757 https://doi.org/10.3354/meps11504 |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic Antarctic Fur Seals |
genre_facet |
Antarc* Antarctic Antarctic Fur Seals |
op_relation |
http://hdl.handle.net/2263/51757 Lowther, AD, Ahonen, H, Hofmeyr, G, Oosthuizen, WC, De Bruyn, PJN, Lydersen, C & Kovacs, KM 2015, 'Reliability of VHF telemetry data for measuring attendance patterns of marine predators : a comparison with time depth recorder data', Marine Ecology-Progress Series, vol. 238, pp. 249-256. 0173-9565 (print) 1439-0485 (online) doi:10.3354/meps11504 |
op_rights |
© Inter-Research 2015 |
op_doi |
https://doi.org/10.3354/meps11504 |
container_title |
Marine Ecology Progress Series |
container_volume |
538 |
container_start_page |
249 |
op_container_end_page |
256 |
_version_ |
1766277123118465024 |