Substantial Variation in Prospecting Behaviour of Young Golden Eagles <i>Aquila chrysaetos</i> Defies Expectations from Potential Predictors
Natal dispersal of large raptors is poorly understood, despite being a crucial transitional life-cycle phase affecting gene flow and population dynamics. A research-gap rarely examined concerns how young dispersing raptors strategize movements towards first settlement on a prospective breeding terri...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-04-01
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| Series: | Diversity |
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| Online Access: | https://www.mdpi.com/1424-2818/15/4/506 |
| _version_ | 1797605759255576576 |
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| author | Alan H. Fielding David Anderson Stuart Benn Robin Reid Ruth Tingay Ewan D. Weston D. Philip Whitfield |
| author_facet | Alan H. Fielding David Anderson Stuart Benn Robin Reid Ruth Tingay Ewan D. Weston D. Philip Whitfield |
| author_sort | Alan H. Fielding |
| collection | DOAJ |
| description | Natal dispersal of large raptors is poorly understood, despite being a crucial transitional life-cycle phase affecting gene flow and population dynamics. A research-gap rarely examined concerns how young dispersing raptors strategize movements towards first settlement on a prospective breeding territory. First territory settlement is a critical decision for a lifetime and can take several years. With such importance, large raptors should theoretically devote considerable effort to acquire accurate information during prospection. Nevertheless, when discovery of territorial opportunities may be difficult, but easier in vacant territories, we posit two extremes in strategizing prospection behaviours: (1) “Quick, grab it when available with limited reconnaissance,” as opposed to (2) “Slow, waiting game with frequent reconnaissance”. We analysed pre-settlement data from 37 GPS-tagged nestling golden eagles, later recorded as having settled on their first territory. The number of eagles’ unique daily visits to their later settled territories was a measure of prospection intensity. We documented substantial variation in prior visits, between less than 10 to several hundred. Analyses considered several potential predictors. We expected a positive association between number of prospecting visits and natal dispersal duration, since with more time to gather information there should be more visits. We also expected fewer prospecting visits in prior vacant territories. Neither of these expectations were supported. There was a non-significant tendency for more prospection visits by males. Our study provides novel information on a seldom-studied behaviour in a large raptor. It illustrates substantial variation in prospecting behaviour, but expectations of potential drivers behind this variation were not confirmed, urging further study. |
| first_indexed | 2024-03-11T05:05:37Z |
| format | Article |
| id | doaj.art-064021fda72649e1b2fdbe9ee231c17e |
| institution | Directory Open Access Journal |
| issn | 1424-2818 |
| language | English |
| last_indexed | 2024-03-11T05:05:37Z |
| publishDate | 2023-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Diversity |
| spelling | doaj.art-064021fda72649e1b2fdbe9ee231c17e2023-11-17T18:56:36ZengMDPI AGDiversity1424-28182023-04-0115450610.3390/d15040506Substantial Variation in Prospecting Behaviour of Young Golden Eagles <i>Aquila chrysaetos</i> Defies Expectations from Potential PredictorsAlan H. Fielding0David Anderson1Stuart Benn2Robin Reid3Ruth Tingay4Ewan D. Weston5D. Philip Whitfield6Natural Research Ltd., Brathens, Aberdeenshire AB31 4BY, UKDave Anderson Ecology Ltd., Callander FK17 8EU, UKRSPB Scotland, Inverness IV2 3BW, UKIndependent Researcher, Isle of Harris HS3 3EZ, UKWild Justice, 9 Lawson Street, Raunds, Northants NN9 6NG, UKNatural Research Ltd., Brathens, Aberdeenshire AB31 4BY, UKNatural Research Ltd., Brathens, Aberdeenshire AB31 4BY, UKNatal dispersal of large raptors is poorly understood, despite being a crucial transitional life-cycle phase affecting gene flow and population dynamics. A research-gap rarely examined concerns how young dispersing raptors strategize movements towards first settlement on a prospective breeding territory. First territory settlement is a critical decision for a lifetime and can take several years. With such importance, large raptors should theoretically devote considerable effort to acquire accurate information during prospection. Nevertheless, when discovery of territorial opportunities may be difficult, but easier in vacant territories, we posit two extremes in strategizing prospection behaviours: (1) “Quick, grab it when available with limited reconnaissance,” as opposed to (2) “Slow, waiting game with frequent reconnaissance”. We analysed pre-settlement data from 37 GPS-tagged nestling golden eagles, later recorded as having settled on their first territory. The number of eagles’ unique daily visits to their later settled territories was a measure of prospection intensity. We documented substantial variation in prior visits, between less than 10 to several hundred. Analyses considered several potential predictors. We expected a positive association between number of prospecting visits and natal dispersal duration, since with more time to gather information there should be more visits. We also expected fewer prospecting visits in prior vacant territories. Neither of these expectations were supported. There was a non-significant tendency for more prospection visits by males. Our study provides novel information on a seldom-studied behaviour in a large raptor. It illustrates substantial variation in prospecting behaviour, but expectations of potential drivers behind this variation were not confirmed, urging further study.https://www.mdpi.com/1424-2818/15/4/506reconnaissance behaviournatal dispersaljuvenile dispersaltransience phaseraptorpopulation ecology |
| spellingShingle | Alan H. Fielding David Anderson Stuart Benn Robin Reid Ruth Tingay Ewan D. Weston D. Philip Whitfield Substantial Variation in Prospecting Behaviour of Young Golden Eagles <i>Aquila chrysaetos</i> Defies Expectations from Potential Predictors Diversity reconnaissance behaviour natal dispersal juvenile dispersal transience phase raptor population ecology |
| title | Substantial Variation in Prospecting Behaviour of Young Golden Eagles <i>Aquila chrysaetos</i> Defies Expectations from Potential Predictors |
| title_full | Substantial Variation in Prospecting Behaviour of Young Golden Eagles <i>Aquila chrysaetos</i> Defies Expectations from Potential Predictors |
| title_fullStr | Substantial Variation in Prospecting Behaviour of Young Golden Eagles <i>Aquila chrysaetos</i> Defies Expectations from Potential Predictors |
| title_full_unstemmed | Substantial Variation in Prospecting Behaviour of Young Golden Eagles <i>Aquila chrysaetos</i> Defies Expectations from Potential Predictors |
| title_short | Substantial Variation in Prospecting Behaviour of Young Golden Eagles <i>Aquila chrysaetos</i> Defies Expectations from Potential Predictors |
| title_sort | substantial variation in prospecting behaviour of young golden eagles i aquila chrysaetos i defies expectations from potential predictors |
| topic | reconnaissance behaviour natal dispersal juvenile dispersal transience phase raptor population ecology |
| url | https://www.mdpi.com/1424-2818/15/4/506 |
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