Résumé
Swallows, along with other aerial insectivores, are experiencing steep population declines. Decreased insect abundance has been implicated as a potential cause of the decline. However, to determine if there is a guild-level effect of reduced insect abundance on swallows, research is needed to examine relationships between insect abundance and breeding success for multiple species. The goal of our study was two-fold. First, we determined if insect abundance during nestling rearing varied with breeding phenology for three species of swallows, Barn (Hirundo rustica), Cliff (Petrochelidon pyrrhonota), and Tree Swallows (Tachycineta bicolor), such that swallows breeding when insects are abundant have greater success. Then we determined if insect abundance was related to nestling survival and mass (as a proxy for postfledgling survival). We collected insects daily at each of three study sites during the breeding season, monitored swallow nests to determine breeding phenology and success, and weighed nestlings at or just prior to the peak of rapid nestling growth to determine mass. We found early hatching Cliff and Tree Swallow nests had higher insect abundance during nestling rearing. However, neither nestling survival nor mass were related to insect abundance. Our results suggest that breeding success in three species of swallows was not related to insect abundance in our study area. We suggest that the role of insect abundance on aerial insectivore declines may vary across their geographic range, and call for broad-scale, multispecies research on aerial insectivore declines.
| Titre traduit de la contribution | No effect of insect abundance on nestling survival or mass for three aerial insectivores |
|---|---|
| Langue d'origine | French |
| Numéro d'article | 19 |
| Journal | Avian Conservation and Ecology |
| Volume | 12 |
| Numéro de publication | 2 |
| DOI | |
| Statut de publication | Published - déc. 2017 |
Note bibliographique
Funding Information:We thank the field assistants and volunteers involved in data collection and insect identification, and D. Hussell for advice on insect sampling. We also thank the private landowners, Acadia University, Ducks Unlimited Canada, Environment and Climate Change Canada, and Parks Canada for permitting access to their properties for field research. We gratefully acknowledge the support of P. Thomas and B. Whittam at Environment and Climate Change Canada, and helpful comments on the manuscript and data analysis from A. Horn, A. MacNeil, and three anonymous reviewers. This research was funded by (in alphabetical order) the Canadian Wildlife Federation, Environment and Climate Change Canada, the Natural Sciences and Engineering Research Council of Canada, New Brunswick Wildlife Trust Fund, Nova Scotia Habitat Conservation Fund, and Wildlife Preservation Canada. Swallow nest monitoring, capture, and handling of nestling swallows, and the collection of insect samples was approved by the Dalhousie University Animal Ethics Committee (protocol nos. 14-007, 14-025).
Publisher Copyright:
© 2017 by the author(s).
ASJC Scopus Subject Areas
- Ecology, Evolution, Behavior and Systematics
- Ecology
- Animal Science and Zoology
- Nature and Landscape Conservation