Effects of geolocators on hatching success, return rates, breeding movements, and change in body mass in 16 species of Arctic-breeding shorebirds.

Emily L. Weiser (1) , Richard B. Lanctot (2) , Stephen Brown (3) , José A. Alves (4, 5) , Phil F. Battley (6) , Rebecca Bentzen (7) , Joël Bêty (8, 9) , Mary Anne Bishop (10) , Megan Boldenow (11) , Loïc Bollache (12) , Bruce Casler , Chris Christie (13) , Jonathan T. Coleman (14) , Jesse R. Conklin (15) , Willow B. English (16) , H. River Gates (2, 3, 17) , Olivier Gilg (18) , Marie-Andrée Giroux (8, 19) , Ken Gosbell (13, 20) , Chris Hassell (20, 21) , Jim Helmericks (22) , Andrew Johnson (23) , Borgný Katrínardóttir (24) , Kari Koivula (25) , Eunbi Kwon (1) , Jean-Francois Lamarre (8) , Johannes Lang (26) , David Lank (27) , Nicolas Lecomte (19) , Joe Liebezeit (28) , Vanessa Loverti (29) , Laura Mckinnon (30, 31) , Clive Minton (13, 20) , David Mizrahi (32) , Erica Nol (30) , Veli-Matti Pakanen (25) , Johanna Perz (30) , Ron Porter (33) , Jennie Rausch (34) , Jeroen Reneerkens (15, 35) , Nelli Rönkä (25) , Sarah Saalfeld (2) , Nathan Senner (36) , Benoît Sittler (37) , Paul A. Smith (34) , Kristine Sowl (38) , Audrey Taylor (39) , David H. Ward (40) , Stephen Yezerinac , Brett K. Sandercock (1)

1 Division of Biology
2 US Fish & Wildlife Service
3 Manomet Center for Conservation Sciences
4 CESAM
5 South Iceland Research Centre
6 Ecology Group
7 Wildlife Conservation Society
8 Departement de Biologie, Chimie et Géographie
9 CEN - Centre d'Etudes Nordiques
10 Prince William Sound Science Center
11 Department of Biology and Wildlife
12 LCE - Laboratoire Chrono-environnement (UMR 6249)
13 Victorian Wader Study Group
14 Queensland Wader Study Group
15 Chair in Global Flyway Ecology - Conservation Ecology Group
16 Department of Biological Sciences [Burnaby]
17 ABR, Inc. - Environmental Research and Services
18 BGS - Biogéosciences [UMR 6282]
19 Canada Research Chair in Polar and Boreal Ecology
20 Australasian Wader Studies Group
21 Global Flyway Network
22 Helmericks Homestead
23 Cornell Laboratory of Ornithology
24 Ecology Department
25 Department of Ecology
26 Institute of Animal Ecology and Nature Education
27 Centre for Wildlife Ecology
28 Audubon Society of Portland
29 US Fish and Wildlife Service
30 Department of Biology
31 Department of Multidisciplinary Studies
32 New Jersey Audubon Society
33 Delaware Bay Shorebird Project
34 ECCC - Environment and Climate Change Canada
35 ARC - Arctic Research Centre [Aarhus]
36 University of Montana
37 Institut für Landespflege
38 Yukon Delta National Wildlife Refuge
39 Department of Geography and Environmental Studies
40 US Geological Survey [Anchorage]

Background Geolocators are useful for tracking movements of long-distance migrants, but potential negative effects on birds have not been well studied. We tested for effects of geolocators (0.8–2.0 g total, representing 0.1–3.9 % of mean body mass) on 16 species of migratory shorebirds, including five species with 2–4 subspecies each for a total of 23 study taxa. Study species spanned a range of body sizes (26–1091 g) and eight genera, and were tagged at 23 breeding and eight nonbreeding sites. We compared breeding performance and return rates of birds with geolocators to control groups while controlling for potential confounding variables. Results We detected negative effects of tags for three small-bodied species. Geolocators reduced annual return rates for two of 23 taxa: by 63 % for semipalmated sandpipers and by 43 % for the arcticola subspecies of dunlin. High resighting effort for geolocator birds could have masked additional negative effects. Geolocators were more likely to negatively affect return rates if the total mass of geolocators and color markers was 2.5–5.8 % of body mass than if tags were 0.3–2.3 % of body mass. Carrying a geolocator reduced nest success by 42 % for semipalmated sandpipers and tripled the probability of partial clutch failure in semipalmated and western sandpipers. Geolocators mounted perpendicular to the leg on a flag had stronger negative effects on nest success than geolocators mounted parallel to the leg on a band. However, parallel-band geolocators were more likely to reduce return rates and cause injuries to the leg. No effects of geolocators were found on breeding movements or changes in body mass. Among-site variation in geolocator effect size was high, suggesting that local factors were important. Conclusions Negative effects of geolocators occurred only for three of the smallest species in our dataset, but were substantial when present. Future studies could mitigate impacts of tags by reducing protruding parts and minimizing use of additional markers. Investigators could maximize recovery of tags by strategically deploying geolocators on males, previously marked individuals, and successful breeders, though targeting subsets of a population could bias the resulting migratory movement data in some species.

Mots clés: Breeding success; Geologger; Global location sensor (GLS); Research impacts; Return rates; Tracking methods; Waders

Domaines: Biodiversité et Ecologie; Ecologie, Environnement

Emily L. Weiser, Richard B. Lanctot, Stephen Brown, José A. Alves, Phil F. Battley, et al.. Effects of geolocators on hatching success, return rates, breeding movements, and change in body mass in 16 species of Arctic-breeding shorebirds.. Movement Ecology, 2016, 4 (1), pp.12. ⟨10.1186/s40462-016-0077-6⟩. ⟨hal-01403340⟩