Disturbance increases high tide travel distance of a roosting shorebird but only marginally affects daily energy expenditure

Linssen, Hans, van de Pol, Martijn, Allen, Andrew, Jans, Mitzi, Ens, Bruno J., Krijgsveld, Karen, Frauendorf, Magali, and Van Der Kolk, Henk-Jan (2019) Disturbance increases high tide travel distance of a roosting shorebird but only marginally affects daily energy expenditure. Avian Research, 10. 31.

[img]
Preview
PDF (Published Version) - Published Version
Available under License Creative Commons Attribution.

Download (1MB) | Preview
View at Publisher Website: https://doi.org/10.1186/s40657-019-0171-...
 
7
80


Abstract

Background: Anthropogenic disturbance can negatively affect an animal's energy budget by evoking movement responses. Existing research focuses mainly on immediate displacement as a disturbance effect, since this can be easily observed in the field. However, effects on movement over longer timescales are poorly examined and it is largely unknown if and to what extent they reflect immediate responses. Longer-term responses could for example be larger than immediate responses if birds, after disturbance, return to the original location and thereby travel twice the immediate disturbed distance.

Methods: We combined GPS tracking data with observational data to quantify the effects of anthropogenic (air force and walkers) and non-anthropogenic disturbances on distances travelled by roosting Eurasian Oystercatchers (Haematopus ostralegus) during the non-breeding season. We compared immediate displacement after a disturbance with distance travelled during the entire high tide period (longer-term response), while accounting for environmental factors. Additionally, we calculated energy expenditure due to disturbance based on observed disturbance frequencies.

Results: Disturbance resulted in an immediate displacement response of ~ 200 m (median). Air force disturbances tended to yield larger immediate responses than walker and, especially, than non-anthropogenic disturbances. Longer-term responses and immediate responses were approximately similar, suggesting that, over longer timescales, spatial disturbance effects in the study area remain confined to immediate effects. However, disturbances were infrequent (0.17 disturbances per bird per hour) and most disturbances were of natural origin (62%). Consequently, anthropogenic disturbance of roosting oystercatchers in the study area on average costs 0.08% of the daily energy expenditure.

Conclusions: Our results suggest that immediate spatial responses to disturbance can be a useful proxy for spatial responses over longer timescales. Over the non-exhaustive range of conditions investigated, energetic consequences of spatial disturbance responses for an oystercatcher in the study area are marginal due to low disturbance levels.

Item ID: 69629
Item Type: Article (Research - C1)
ISSN: 2053-7166
Keywords: Biologging, Disturbance, Haematopus ostralegus, High tide roost, Movement ecology, Shorebird
Copyright Information: © The Author(s) 2019. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
Date Deposited: 21 Oct 2021 03:23
FoR Codes: 31 BIOLOGICAL SCIENCES > 3103 Ecology > 310305 Marine and estuarine ecology (incl. marine ichthyology) @ 33%
31 BIOLOGICAL SCIENCES > 3103 Ecology > 310301 Behavioural ecology @ 33%
31 BIOLOGICAL SCIENCES > 3103 Ecology > 310307 Population ecology @ 34%
SEO Codes: 18 ENVIRONMENTAL MANAGEMENT > 1802 Coastal and estuarine systems and management > 180201 Assessment and management of coastal and estuarine ecosystems @ 100%
Downloads: Total: 80
Last 12 Months: 26
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page