DOI: 10.5061/dryad.9ghx3ffz4
title: Reproductive success of three parid species in managed boreal forests

description: Anthropogenic impacts, such as forestry and land use practices, can
 deteriorate habitat quality, affecting reproductive success and leading to
 population decline. The boreal willow tit (Poecile montanus) population
 has dramatically declined in Finland. In contrast, great tits (Parus
 major) and blue tits (Cyanistes caeruleus), both of temperate origin, have
 expanded their ranges and increased in numbers in Northern Finland. It has
 been suggested that the decline in the willow tit population is mainly
 caused by the reduction of breeding sites and wintering areas resulting
 from habitat loss and degradation. We investigated whether forest
 management influences the reproductive success of willow tits, great tits,
 and blue tits, including recruitment across years, while considering other
 factors such as possible intra- and interspecific competition. We combined
 long-term breeding data (1990-2020) from Oulu, Finland, with spatial data
 on forest management activities and analysed the data using (generalized)
 linear mixed-effect models. Results varied depending on the breeding
 parameter, species, and forest management method. Forestry had no
 significant effect on clutch size. We found negative effects of thinnings
 on nestling survival and growth in great and blue tits, with
 clear-cuttings negatively affecting blue tit nestling growth. However,
 recent clear-cuttings had positive effects on willow tit nestling survival
 and growth. Despite these benefits, clear-cuttings near nesting sites were
 associated with reduced willow tit local recruitment probability, leading
 to an overall negative impact on the population. These findings may arise
 from forest management influences on food availability; certain stages
 following clear-cutting may improve the food availability for boreal
 willow tit nestlings, yet thinnings may reduce foraging opportunities for
 great tits and blue tits. While some positive effects of forestry on
 willow tits were recorded, they may not be enough to offset the
 well-established negative impacts of forestry on the loss of optimal
 wintering and breeding habitats.
description: # Reproductive success of three parid species in managed boreal forests
 Dataset DOI:
 [10.5061/dryad.9ghx3ffz4](https://doi.org/10.5061/dryad.9ghx3ffz4) ##
 Description of the data and file structure This repository includes the
 data and R scripts required for analysing and creating figures presented
 in the original research article, "Reproductive success of three
 parid species in managed boreal forests." All CSV files (=the data)
 were generated with similar column names in English (Table 1). They are
 the variables also used in the analysis. See the original research article
 for further explanation of the methods and more detailed variable
 descriptions. Table 1. Explanations of the data column names in
 files BT_data.csv, GT_data.csv, and WT_data.csv. | Column name |
 Explanation | Unit | |
 :--------------------------------------------------------------------------------------------------- | :---------------------------------------------------------------------- | :--------------------------------------------- | | row | row number | 
 
 | | location | location in the study area | character | | year | study
 year | 
 
 | | fring | female ring number (ID) | character | | 0-30v.cc57m | 0-30
 years from clear-cutting (57 m) | % of coverage | | 0-30v.cc113m | 0-30
 years from clear-cutting (113 m) | % of coverage | | 0-30v.cc329m | 0-30
 years from clear-cutting (329 m) | % of coverage | | 0-30v.cc500m | 0-30
 years from clear-cutting (500 m) | % of coverage | | 0-30v.thin57m | 0-30
 years from thinning (57 m) | % of coverage | | 0-30v.thin113m | 0-30 years
 from thinning (113 m) | % of coverage | | 0-30v.thin329m | 0-30 years from
 thinning (329 m) | % of coverage | | 0-30v.thin500m | 0-30 years from
 thinning (500 m) | % of coverage | | 0-10v.cc57m | 0-10 years from
 clear-cutting (57 m) | % of coverage | | 0-10v.cc113m | 0-10 years from
 clear-cutting (113 m) | % of coverage | | 0-10v.cc329m | 0-10 years from
 clear-cutting (329 m) | % of coverage | | 0-10v.cc500m | 0-10 years from
 clear-cutting (500 m) | % of coverage | | 11-30v.cc57m | 11-30 years from
 clear-cutting (57 m) | % of coverage | | 11-30v.cc113m | 11-30 years from
 clear-cutting (113 m) | % of coverage | | 11-30v.cc329m | 11-30 years from
 clear-cutting (329 m) | % of coverage | | 11-30v.cc500m | 11-30 years from
 clear-cutting (500 m) | % of coverage | | 0-10v.thin57m | 0-10 years from
 thinning (57 m) | % of coverage | | 0-10v.thin113m | 0-10 years from
 thinning (113 m) | % of coverage | | 0-10v.thin329m | 0-10 years from
 thinning (329 m) | % of coverage | | 0-10v.thin500m | 0-10 years from
 thinning (500 m) | % of coverage | | 11-30v.thin57m | 11-30  years from
 thinning (57 m) | % of coverage | | 11-30v.thin113m | 11-30 years from
 thinning (113 m) | % of coverage | | 11-30v.thin329m | 11-30  years from
 thinning (329 m) | % of coverage | | 11-30v.thin500m | 11-30  years from
 thinning (500 m) | % of coverage | | 0-4v.cc57m | 0-4 years from
 clear-cutting (57 m) | % of coverage | | 5-10v.cc57m | 5-10 years from
 clear-cutting (57 m) | % of coverage | | 11-20v.cc57m | 11-20 years from
 clear-cutting (57 m) | % of coverage | | 21-30v.cc57m | 21-30 years from
 clear-cutting (57 m) | % of coverage | | 0-4v.cc113m | 0-4 years from
 clear-cutting (113 m) | % of coverage | | 5-10v.cc113m | 5-10 years from
 clear-cutting (113 m) | % of coverage | | 11-20v.cc113m | 11-20 years from
 clear-cutting (113 m) | % of coverage | | 21-30v.cc113m | 21-30 years from
 clear-cutting (113 m) | % of coverage | | 0-4v.cc329m | 0-4 years from
 clear-cutting (329 m) | % of coverage | | 5-10v.cc329m | 5-10 years from
 clear-cutting (329 m) | % of coverage | | 11-20v.cc329m | 11-20 years from
 clear-cutting (329 m) | % of coverage | | 21-30v.cc329m | 21-30 years from
 clear-cutting (329 m) | % of coverage | | 0-4v.cc500m | 0-4 years from
 clear-cutting (500 m) | % of coverage | | 5-10v.cc500m | 5-10 years from
 clear-cutting (500 m) | % of coverage | | 11-20v.cc500m | 11-20 years from
 clear-cutting (500 m) | % of coverage | | 21-30v.cc500m | 21-30 years from
 clear-cutting (500 m) | % of coverage | | 0-4v.thin57m | 0-4 years from
 thinning (57 m) | % of coverage | | 5-10v.thin57m | 5-10 years from
 thinning (57 m) | % of coverage | | 11-20v.thin57m | 11-20 years from
 thinning (57 m) | % of coverage | | 21-30v.thin57m | 21-30 years from
 thinning (57 m) | % of coverage | | 0-4v.thin113m | 0-4 years from
 thinning (113 m) | % of coverage | | 5-10v.thin113m | 5-10 years from
 thinning (113 m) | % of coverage | | 11-20v.thin113m | 11-20 years from
 thinning (113 m) | % of coverage | | 21-30v.thin113m | 21-30 years from
 thinning (113 m) | % of coverage | | 0-4v.thin329m | 0-4 years from
 thinning (329 m) | % of coverage | | 5-10v.thin329m | 5-10 years from
 thinning (329 m) | % of coverage | | 11-20v.thin329m | 11-20 years from
 thinning (329 m) | % of coverage | | 21-30v.thin329m | 21-30 years from
 thinning (329 m) | % of coverage | | 0-4v.thin500m | 0-4 years from
 thinning (500 m) | % of coverage | | 5-10v.thin500m | 5-10 years from
 thinning (500 m) | % of coverage | | 11-20v.thin500m | 11-20 years from
 thinning (500 m) | % of coverage | | 21-30v.thin500m | 21-30 years from
 thinning (500 m) | % of coverage | | richness57m | forest type gradient
 (57 m) | relative gradient value from 1 to 6 | | richness113m | forest
 type gradient (113 m) | relative gradient value from 1 to 6 | |
 richness329m | forest type gradient (329 m) | relative gradient value from
 1 to 6 | | richness500m | forest type gradient (500 m) | relative gradient
 value from 1 to 6 | | clutch | clutch size | number of eggs in a nest | |
 timing | date of the first laid egg | a continuos number of "May
 days", 1=1st of May | | nndist | distance to the nearest
 intraspecific neighbour (either GT, WT or BT) | meters | | gt\_vs\_wt |
 great tit distance to nearest willow tit neighbour | meters | | wt\_vs\_gt
 | willow tit distance to nearest great tit neighbour | meters | |
 bt\_vs\_gt | distance to nearest great tit neighbour | meters | |
 gt\_vs\_bt | distance to nearest blue tit neighbour | meters | | fage |
 female age | binomial (0=juvenile, 1=older, unknown) | | dcentre |
 distance to study area centre | meters | | hatched | number of hatched
 nestlings | 
 
 | | recruit | number of recruits (per nest) | 
 
 | | meanweight | mean nestling body mass | grams | | meanwing | mean
 nestling wing length | millimeters | | fledged | number of fledged
 nestlings | 
 
 | | measurer | name of the measurer | character | ### Files and variables
 #### File: BT_data.csv **Description:** A CSV file containing the original
 data and variables used for blue tit analysis in the research article.
 Empty cells in the data represent genuine missing information, which can
 occur when collecting data from live birds. The missing data is typically
 caused by a lost or predated nest after nesting has begun. Other possible
 reasons include a bird caught for ringing that accidentally escapes before
 measurements are taken, or a parent bird that cannot be caught for ringing
 and measurements before the nestlings fledge.  ##### Variables * Please
 see Table 1 (above) for variable names and descriptions.  #### File:
 BT_R-script.R **Description:** An R script for analysing (LMM and GLMM,
 depending on the response variable) and creating figures of the blue tit
 data provided in file BT_data.csv. The analyses should preferably be
 conducted in RStudio. #### File: GT_R-script.R **Description:** An R
 script for analysing (LMM and GLMM, depending on the response variable)
 and creating figures of the great tit data provided in file GT_data.csv.
 The analyses should preferably be conducted in RStudio. #### File:
 GT_data.csv **Description:** A CSV file containing the original data and
 variables used for great tit analysis in the research article. Empty cells
 in the data represent genuine missing information, which can occur when
 collecting data from live birds. The missing data is typically caused by a
 lost or predated nest after nesting has begun. Other possible reasons
 include a bird caught for ringing that accidentally escapes before
 measurements are taken, or a parent bird that cannot be caught for ringing
 and measurements before the nestlings fledge.  ##### Variables * Please
 see Table 1 (above) for variable names and descriptions.  #### File:
 WT_R-script.R **Description:** An R script for analysing (LMM and GLMM,
 depending on the response variable) and creating figures of the willow tit
 data provided in file WT_data.csv. The analyses should preferably be
 conducted in RStudio. #### File: WT_data.csv **Description:** A CSV file
 containing the original data and variables used for willow tit analysis in
 the research article. Empty cells in the data represent genuine missing
 information, which can occur when collecting data from live birds. The
 missing data is typically caused by a lost or predated nest after nesting
 has begun. Other possible reasons include a bird caught for ringing that
 accidentally escapes before measurements are taken, or a parent bird that
 cannot be caught for ringing and measurements before the nestlings
 fledge.  ##### Variables * Please see Table 1 (above) for variable names
 and descriptions.  ## Code/software * Microsoft Excel was needed to
 inspect and modify the Excel files. * R 4.1.2 and RStudio were used to
 analyse the data and draw figures. The latest versions of the following
 packages were used: * MuMIn * car * effects * lme4 * lmerTest * DHARMa *
 weights ## Access information Other publicly accessible locations of the
 data: * The data is otherwise accessible by personal request. Data was
 derived from the following sources: * A long-term research on breeding
 passerines was conducted by professor Markku Orell and his research group
 from Ecology and Genetics Reseach Unit, University of Oulu, Finland.