Data from: Severe recent decrease of adult body mass in a declining insectivorous bird population
| Main Authors: | Rioux Paquette, Sébastien, Pelletier, Fanie, Garant, Dany, Bélisle, Marc |
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| Format: | info dataset Journal |
| Terbitan: |
, 2014
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| Subjects: | |
| Online Access: |
https://zenodo.org/record/4956963 |
Daftar Isi:
- Migratory bird species that feed on air-borne insects are experiencing widespread regional declines, but these remain poorly understood. Agricultural intensification in the breeding range is often regarded as one of the main drivers of these declines. Here, we tested the hypothesis that body mass in breeding individuals should reflect habitat quality in an aerial insectivore, the tree swallow (Tachycineta bicolor), along a gradient of agricultural intensity. Our dataset was collected over 7 years (2005–2011) and included 2918 swallow captures and 1483 broods. Analyses revealed a substantial decline of the population over the course of the study (−19% occupancy rate), mirrored by decreasing body mass. This trend was especially severe in females, representing a total loss of 8% of their mass. Reproductive success was negatively influenced by intensive agriculture, but did not decrease over time. Interestingly, variation in body mass was independent of breeding habitat quality, leading us to suggest that this decline in body mass may result from carry-over effects from non-breeding areas and affect population dynamics through reduced survival. This work contributes to the growing body of evidence suggesting that declines in migratory aerial insectivores are driven by multiple, complex factors requiring better knowledge of year-round habitat use.
- Female dataDataset comprising all captures of female tree swallows used in the study between 2005-2011. This dataset was used for analyses of body mass in females and a subset (only females captured at least in two different years) was used for analyses of within- vs between-individual change in body mass across years.femaledata.xlsMale dataDataset comprising all captures of male tree swallows used in the study between 2005-2011. This dataset was used for analyses of body mass in males.maledata.xlsBreeding success dataThis dataset comprises data on all clutches monitored between 2005-2011 and was used for analyses of breeding success (number of hatchlings and fledglings).clutchdata.xls