Why do earlier‐arriving migratory birds have better breeding success?
Abstract In migratory birds, early arrival on breeding sites is typically associated with greater breeding success, but the mechanisms driving these benefits are rarely known. One mechanism through which greater breeding success among early arrivers can potentially be achieved is the increased time...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2019-08-01
|
| Series: | Ecology and Evolution |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/ece3.5441 |
| _version_ | 1818939901341597696 |
|---|---|
| author | Catriona A. Morrison José A. Alves Tómas G. Gunnarsson Böðvar Þórisson Jennifer A. Gill |
| author_facet | Catriona A. Morrison José A. Alves Tómas G. Gunnarsson Böðvar Þórisson Jennifer A. Gill |
| author_sort | Catriona A. Morrison |
| collection | DOAJ |
| description | Abstract In migratory birds, early arrival on breeding sites is typically associated with greater breeding success, but the mechanisms driving these benefits are rarely known. One mechanism through which greater breeding success among early arrivers can potentially be achieved is the increased time available for replacement clutches following nest loss. However, the contribution of replacement clutches to breeding success will depend on seasonal variation in nest survival rates, and the consequences for juvenile recruitment of hatching at different times in the season. In particular, lower recruitment rates of late‐hatched chicks could offset the benefits to early arrivers of being able to lay replacement clutches, which would reduce the likelihood of replacement clutch opportunities influencing selection on migratory timings. Using a simulation model of time‐constrained capacity for replacement clutches, paramaterized with empirically‐derived estimates from avian migratory systems, we show that greater reproductive success among early‐arriving individuals can arise solely through the greater time capacity for replacement clutches among early arrivers, even when later renesting attempts contribute fewer recruits to the population. However, these relationships vary depending on the seasonal pattern of nest survival. The benefits of early arrival are greatest when nest survival rates are constant or decline seasonally, and early arrival is least beneficial when nest success rates increase over the breeding season, although replacement clutches can mitigate this effect. The time benefits of early arrival facilitating replacement clutches following nest loss may therefore be an important but overlooked source of selection on migratory timings. Empirical measures of seasonal variation in nest survival, renesting, and juvenile recruitment rates are therefore needed in order to identify the costs and benefits associated with individual migration phenology, the selection pressures influencing migratory timings, and the implications for ongoing shifts in migration and breeding phenology. |
| first_indexed | 2024-12-20T06:31:06Z |
| format | Article |
| id | doaj.art-f2db21c70fc54e17b1a506fc852afa1d |
| institution | Directory Open Access Journal |
| issn | 2045-7758 |
| language | English |
| last_indexed | 2024-12-20T06:31:06Z |
| publishDate | 2019-08-01 |
| publisher | Wiley |
| record_format | Article |
| series | Ecology and Evolution |
| spelling | doaj.art-f2db21c70fc54e17b1a506fc852afa1d2022-12-21T19:50:08ZengWileyEcology and Evolution2045-77582019-08-019158856886410.1002/ece3.5441Why do earlier‐arriving migratory birds have better breeding success?Catriona A. Morrison0José A. Alves1Tómas G. Gunnarsson2Böðvar Þórisson3Jennifer A. Gill4School of Biological Sciences University of East Anglia Norwich UKDepartment of Biologia & CESAM – Centre for Environmental and Marine Studies University of Aveiro Aveiro PortugalSouth Iceland Research Centre University of Iceland Laugarvatn IcelandSouth Iceland Research Centre University of Iceland Laugarvatn IcelandSchool of Biological Sciences University of East Anglia Norwich UKAbstract In migratory birds, early arrival on breeding sites is typically associated with greater breeding success, but the mechanisms driving these benefits are rarely known. One mechanism through which greater breeding success among early arrivers can potentially be achieved is the increased time available for replacement clutches following nest loss. However, the contribution of replacement clutches to breeding success will depend on seasonal variation in nest survival rates, and the consequences for juvenile recruitment of hatching at different times in the season. In particular, lower recruitment rates of late‐hatched chicks could offset the benefits to early arrivers of being able to lay replacement clutches, which would reduce the likelihood of replacement clutch opportunities influencing selection on migratory timings. Using a simulation model of time‐constrained capacity for replacement clutches, paramaterized with empirically‐derived estimates from avian migratory systems, we show that greater reproductive success among early‐arriving individuals can arise solely through the greater time capacity for replacement clutches among early arrivers, even when later renesting attempts contribute fewer recruits to the population. However, these relationships vary depending on the seasonal pattern of nest survival. The benefits of early arrival are greatest when nest survival rates are constant or decline seasonally, and early arrival is least beneficial when nest success rates increase over the breeding season, although replacement clutches can mitigate this effect. The time benefits of early arrival facilitating replacement clutches following nest loss may therefore be an important but overlooked source of selection on migratory timings. Empirical measures of seasonal variation in nest survival, renesting, and juvenile recruitment rates are therefore needed in order to identify the costs and benefits associated with individual migration phenology, the selection pressures influencing migratory timings, and the implications for ongoing shifts in migration and breeding phenology.https://doi.org/10.1002/ece3.5441arrival datesdemographylaying datesmigrationphenologyproductivity |
| spellingShingle | Catriona A. Morrison José A. Alves Tómas G. Gunnarsson Böðvar Þórisson Jennifer A. Gill Why do earlier‐arriving migratory birds have better breeding success? Ecology and Evolution arrival dates demography laying dates migration phenology productivity |
| title | Why do earlier‐arriving migratory birds have better breeding success? |
| title_full | Why do earlier‐arriving migratory birds have better breeding success? |
| title_fullStr | Why do earlier‐arriving migratory birds have better breeding success? |
| title_full_unstemmed | Why do earlier‐arriving migratory birds have better breeding success? |
| title_short | Why do earlier‐arriving migratory birds have better breeding success? |
| title_sort | why do earlier arriving migratory birds have better breeding success |
| topic | arrival dates demography laying dates migration phenology productivity |
| url | https://doi.org/10.1002/ece3.5441 |
| work_keys_str_mv | AT catrionaamorrison whydoearlierarrivingmigratorybirdshavebetterbreedingsuccess AT joseaalves whydoearlierarrivingmigratorybirdshavebetterbreedingsuccess AT tomasggunnarsson whydoearlierarrivingmigratorybirdshavebetterbreedingsuccess AT boðvarþorisson whydoearlierarrivingmigratorybirdshavebetterbreedingsuccess AT jenniferagill whydoearlierarrivingmigratorybirdshavebetterbreedingsuccess |