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Cover, not caging, influences chronic physiological stress in a ground-nesting bird

journal contribution
posted on 01.09.2015, 00:00 authored by Laura Xin Lu Tan, Kate BuchananKate Buchanan, G S Maguire, Mike WestonMike Weston
Predator exclosures ('nest cages') around nests are increasingly used to enhance hatching success of declining ground-nesting birds. However, such exclosures are contentious and have been suggested to have detrimental effects on the species which they aim to protect. This study examines whether exclosures increase physiological stress of incubating birds, a hitherto unrecognised and untested potential drawback of exclosures. Red-capped plover Charadrius ruficapillus hatching success was radically altered and significantly higher for nests with exclosures (96.2%) compared with those without (6.8%). Chronic physiological stress in parents (as measured by the heterophil/lymphocyte [H/L] ratio in blood) did not vary between nests with and without exclosures, or between the sexes. However the absence of vegetative cover at the nest site was associated with a 62.7% elevation in H/L ratio, indicating that incubating birds which place their nests in the open are subject to increased levels of chronic stress. The results from this study demonstrate the fundamental importance of predation for the nesting success of this species and confirm that chronic stress levels are not a detrimental side effect of exclosure use.

History

Journal

Journal of avian biology

Volume

46

Issue

5

Pagination

482 - 488

Publisher

Blackwell Publishing

Location

Chichester, Eng.

ISSN

0908-8857

eISSN

1600-048X

Language

eng

Publication classification

C Journal article; C1 Refereed article in a scholarly journal

Copyright notice

2015, Wiley