Data from: Weather extremes in the Mediterranean winter are associated with reduced apparent survival and delayed initiation of egg-laying in a migratory raptor
Data files
Dec 17, 2025 version files 1.96 MB
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Falco_tinnunculus_breeding_attempts.csv
221.79 KB
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Falco_tinnunculus_capture_histories.csv
1.52 MB
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Falco_tinnunculus_encounters.csv
204.68 KB
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README.md
14.42 KB
Abstract
Climate change increases the frequency of extreme weather events, to which migratory raptors are particularly vulnerable. We monitored a population of Eurasian Kestrels (Falco tinnunculus) breeding in nest boxes in western Finland (approx. 63°N, 23°E) and applied a capture–mark–recapture scheme to adults encountered at nests from 1985 to 2013 to examine how environmental conditions affect their apparent survival. We included density data of their primary prey (voles), collected during the early breeding season within the study area, as a predictor of annual survival. We also recorded the initiation dates of egg laying from 1985 to 2018 to test whether variables representing winter weather conditions predict laying phenology, with prey density included as a covariate. We found that both frequent and infrequent winter rain were associated with reduced apparent survival, and that vole abundance in the breeding area was negatively correlated with apparent survival. Additionally, we found that frequent precipitation in the wintering grounds led to delayed laying the following spring in years of low vole abundance.
Dataset DOI: 10.5061/dryad.gqnk98t2m
Description of the data and file structure
Data were collected to estimate apparent survival rate and timing of laying of Eurasian Kestrels in relation to the abundance of main prey (voles) and various weather indicators.
Files and variables
File: Falco_tinnunculus_breeding_attempts.csv
Description: Nesting attempts of Eurasian Kestrels recorded in 1985–2018 at Kauhava-Lapua study area located in Western Finland
Missing values are indicated by "NA"
Variables
- id: unique ID no. of the nesting attempt
- year: year during which the nesting attempt occurred
- box: unique ID of the nest-box or natural stick nest in which the nesting attempt occurred
- lon_j: longitudinal WGS 84 coordinates of the nesting attempt with 1e-6 degree jitter added to duplicate coordinates
- lat_j: latitudinal WGS 84 coordinates of the nesting attempt with 1e-6 degree jitter added to duplicate coordinates
- feband: individual band ID of the female parent
- feage: age of the female parent as calendar years (2 = second-year, >2 = older than second-year)
- feday: date of capture of the female parent (1 = April 1st)
- maband: individual band ID of the male parent
- maage: age of the male parent as calendar years (2 = second-year, >2 = older than second-year)
- maday: date of capture of the male parent (1 = April 1st)
- laydate: date of laying of the first egg (1 = April 1st)
- voles_unstandardised: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (unstandardised)
- voles: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised)
File: Falco_tinnunculus_encounters.csv
Description: Encounter events of breeding Eurasian Kestrels captured at their nests in 1985–2013 at Kauhava-Lapua study area located in Western Finland
Missing values are indicated by "NA"
Variables
- id: ID no. of the corresponding nesting attempt
- year: year during which the encounter occurred
- box: ID of the nest-box or natural stick nest in which the corresponding nesting attempt occurred
- band: band ID of the encountered individual
- sex: sex of the encountered individual (M = male, F = female)
- age: age of the encountered individual as calendar years (2 = second-year, >2 = older than second-year)
- capturedate: date of encounter (1 = April 1st)
- laydate: date of laying of the first egg (1 = April 1st) of the corresponding nesting attempt
- voles_unstandardised: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (unstandardised)
- voles: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised)
File: Falco_tinnunculus_capture_histories.csv
Description: Complete capture histories of breeding Eurasian Kestrels captured at their nests in 1985–2013 (one capture occasion per year) at Kauhava-Lapua study area located in Western Finland
Variables
- band: individual band ID
- ch: capture history; each digit represents one capture occasion (1 = encountered, 0 = not encountered)
- sex: sex of the individual (M = male, F = female)
- age.1985: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 1985
- age.1986: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 1986
- age.1987: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 1987
- age.1988: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 1988
- age.1989: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 1989
- age.1990: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 1990
- age.1991: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 1991
- age.1992: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 1992
- age.1993: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 1993
- age.1994: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 1994
- age.1995: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 1995
- age.1996: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 1996
- age.1997: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 1997
- age.1998: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 1998
- age.1999: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 1999
- age.2000: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 2000
- age.2001: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 2001
- age.2002: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 2002
- age.2003: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 2003
- age.2004: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 2004
- age.2005: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 2005
- age.2006: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 2006
- age.2007: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 2007
- age.2008: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 2008
- age.2009: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 2009
- age.2010: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 2010
- age.2011: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 2011
- age.2012: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 2012
- age.2013: age as calendar years (0 = preceding first encounter, 2 = second-year, >2 = older than second-year) in 2013
- tsm.1985: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 1985
- tsm.1986: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 1986
- tsm.1987: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 1987
- tsm.1988: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 1988
- tsm.1989: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 1989
- tsm.1990: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 1990
- tsm.1991: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 1991
- tsm.1992: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 1992
- tsm.1993: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 1993
- tsm.1994: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 1994
- tsm.1995: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 1995
- tsm.1996: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 1996
- tsm.1997: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 1997
- tsm.1998: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 1998
- tsm.1999: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 1999
- tsm.2000: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 2000
- tsm.2001: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 2001
- tsm.2002: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 2002
- tsm.2003: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 2003
- tsm.2004: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 2004
- tsm.2005: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 2005
- tsm.2006: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 2006
- tsm.2007: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 2007
- tsm.2008: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 2008
- tsm.2009: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 2009
- tsm.2010: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 2010
- tsm.2011: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 2011
- tsm.2012: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 2012
- tsm.2013: time since marking (0 = first encounter or preceding first encounter, 1 = all subsequent capture occasions) in 2013
- voles.1985: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 1985
- voles.1986: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 1986
- voles.1987: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 1987
- voles.1988: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 1988
- voles.1989: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 1989
- voles.1990: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 1990
- voles.1991: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 1991
- voles.1992: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 1992
- voles.1993: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 1993
- voles.1994: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 1994
- voles.1995: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 1995
- voles.1996: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 1996
- voles.1997: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 1997
- voles.1998: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 1998
- voles.1999: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 1999
- voles.2000: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 2000
- voles.2001: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 2001
- voles.2002: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 2002
- voles.2003: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 2003
- voles.2004: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 2004
- voles.2005: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 2005
- voles.2006: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 2006
- voles.2007: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 2007
- voles.2008: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 2008
- voles.2009: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 2009
- voles.2010: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 2010
- voles.2011: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 2011
- voles.2012: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 2012
- voles.2013: abundance index of voles (Microtus and Myodes) during May in Kauhava-Lapua study area (standardised) in 2013
Code/software
All datasets are supplied as comma-delimited (.csv) files and can be viewed using any CSV-compatible software.
Access information
Breeding adult kestrels were captured at their nests using swing-door traps. Each individual, identified by a unique leg-ring number, was assigned a capture history by arranging successful capture events (denoted as “1”) and capture occasions during which the individual was not detected (denoted as “0”) into a timeline of 29 digits, with each digit representing a capture occasion (year). Captured individuals were sexed and aged into two classes: second-year (“2”) and after–second-year (“>2”).
Timing of egg laying was estimated either by revisiting nests with incomplete clutches or by back-dating from the hatching date, assuming a two-day laying interval and a 30-day incubation period.
Data on Eurasian Kestrels were accompanied by annual abundance indices of their primary prey (voles of the genera Microtus and Myodes), collected in mid-May within the study area. The number of voles trapped with snap traps during one sampling period was totaled and divided by the number of trap-nights to derive an index of prey abundance.