Differences in the use of surface water resources by desert birds are revealed using isotopic tracers
- Published
- Accepted
- Subject Areas
- Ecology, Zoology, Anatomy and Physiology, Biosphere Interactions
- Keywords
- water balance, evaporative water loss, stable isotopes, metabolic water, drinking behaviours, surface water, preformed water, drinking behaviors
- Copyright
- © 2018 Smit et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2018. Differences in the use of surface water resources by desert birds are revealed using isotopic tracers. PeerJ Preprints 6:e3167v3 https://doi.org/10.7287/peerj.preprints.3167v3
Abstract
The scarcity of free-standing water sources is a key determinant of animal and plant community structure in arid environments, and an understanding of the extent to which particular species use surface water is vital for modelling the effects of climate change on desert avifauna. We investigated interspecific variation in the use of artificial water sources among birds in the Kalahari Desert, South Africa, by 1) observations at waterholes and 2) tracing spatial water-use patterns during summer by isotopically-labelled water sources and blood sampling. More than 50% of the avian community (primarily insectivores and omnivores) were not observed to drink. The majority (53%) of species drinking at waterholes were granivorous, and their use of surface water was best predicted by their relative abundance in the community. Species representing the remaining dietary guilds drank significantly more on hot days. Blood samples revealed that only 11 of 42 species (mostly granivores and a few omnivores) showed evidence of drinking at a waterhole with enriched deuterium values; on average, in the latter birds, water from the enriched waterhole accounted for ~38% of their body water pool. These findings illustrate that two methods employed in this study provide different, but complementary data on the relative importance of a water source for an avian community. Although our results suggest that most avian species are independent of surface water, drinking patterns on the hottest days during our study period suggest that free-standing water might become more important for some of the non-drinking species under hotter climatic conditions.
Author Comment
The grammatical error in the previous title was corrected. The paper was also revised following peer review in The Auk (currently in press).
Supplemental Information
Supplementary Material
Supplementary Table S1 and Table S2