DOI: 10.5061/dryad.k0p2ngfjw
title: Data from: Benefit or ecological trap? Monitoring the effects of small clear-cuts on capercaillie Tetrao urogallus and its mammalian predators

description: The shift to “close to nature forestry” as the dominating forestry regime
 in Western-European forests has resulted in increasing timber volume and
 denser forests with negative effects on photophilic species. Hence, there
 is an increasing focus on active habitat management measures to support
 these species. To guarantee that the measures prove beneficial to the
 target species, it is essential to evaluate both their benefits as well as
 possible negative effects. However, while species’ population trends are
 often well-studied, rigorous monitoring schemes for management
 interventions are often lacking. Here we applied a
 before-after-control-intervention (BACI) study design over multiple years
 to study the effects of actively creating small clear-cuts of up to 1
 hectare on the occurrence of western capercaillie (Tetrao urogallus) and
 its mammalian predators. While habitat management measures had immediate
 positive effects on the probability of capercaillie presence that remained
 constant during the 5 years after the intervention, predator presence did
 not increase in the years after clear-cutting. Assuming that predator
 activity density is related to predation risk, this would refute the
 hypothesis that the intervention created an ecological trap. Our study
 confirms correlative studies indicating that the creation of small
 clear-cuts in a closed forest matrix represents an effective measure for
 improving capercaillie habitats in Western-European lower mountain
 forests, and contributes to a solid basis for science-based, large-scale
 management strategies to comply with international species conservation
 legislation.
description: # Data from: Benefit or ecological trap? Monitoring the effects of small
 clear-cuts on capercaillie Tetrao urogallus and its mammalian predators
 Dataset DOI: [10.5061/dryad.k0p2ngfjw](10.5061/dryad.k0p2ngfjw) ##
 Description of the data and file structure Data was collected to study the
 effects of actively creating small clear-cuts of up to 1 ha on the
 occurrence of western capercaillie (*Tetrao urogallus*) and its mammalian
 predators. We collected data on capercaillie occurrence and habitat
 suitability on 30 paired study sites (15 pairs), distributed across the
 Black Forest. For each pair, a small clear-cut of 0.7–1.0 ha was
 experimentally created in the centre of one study site (intervention, I),
 while the other served as control (control, C). On each study site we
 systematically placed 13 sampling plots on which the terrestrial recording
 of capercaillie occurrence and habitat variables was carried out once per
 year from 2018 to 2023. Furthermore, on each study site we monitored
 potential capercaillie predators by camera trapping from 2018 to 2021 and
 calculated predator trapping rates for red fox (*Vulpes vulpes*), badger
 (*Meles meles*), marten (*Martes* sp.) and wild boar (*Sus scrofa*). ###
 Files and variables #### File: capercaillie\_clearcut\_data.CSV
 **Description:**  Data on capercaillie (*Tetrao urogallus*) occurrence at
 the plots between 2018-2023 and habitat suitability in 2018, before the
 intervention. **Variables:** * plot_id: Individual identifier for each
 sampling plot. This id consists of the number of the site pair (1-15), an
 I for intervention or a C for control and the number of the sampling plot
 (1-13). * site_pair: Number of the paired sites (1-15). * study_site:
 Individual identifier for each study site. This id consists of the number
 of the site pair and an I for intervention or a C for control. * year: The
 year of the sampling. * capercaillie_occurrence: 0 for no capercaillie
 signs (e.g. feathers, faeces, dust baths) were found and 1 for
 capercaillie signs were found. * period: B for before the intervention
 (2018) and A for after the intervention (2019-2023). * treatment: I for
 intervention (clear-cut) or C for control. * hab_suit_2018: Initial
 habitat suitability in 2018, before the creation of the clear-cuts in
 2018. We modelled habitat suitability as the probability of finding
 capercaillie signs at a plot as a function of the habitat variables using
 the model of Coppes et al. (2020), which had been calibrated with data
 collected with the same sampling method from different European
 capercaillie populations and therefore provides a robust estimate. ####
 File: predator\_clearcut\_data.CSV **Description:**  Data on predator
 trapping rates at the plots between 2018-2021. **Variables:** * site_pair:
 Number of the paired sites (1-15). * study_site: Individual identifier for
 each study site. This id consists of the number of the site pair and an I
 for intervention or a C for control. * year: The year of the sampling. *
 species: Name of the species for which the trapping rate was calculated. *
 trapping_rates: We calculated trapping rates per species, season and site
 as the number of trapping events (accounting for the number of
 individuals, e.g. counting a trapping event with two individuals twice)
 divided by the number of days the camera was active. * period: B for
 before the intervention (2018) and A for after the intervention
 (2019-2023). * treatment: I for intervention (clear-cut) or C for control.
 Reference: Coppes, J., Kämmerle, J.-L., Grünschachner-Berger, V.,
 Braunisch, V., Bollmann, K., Mollet, P., Suchant, R. and Nopp-Mayr, U.
 2020. Consistent effects of wind turbines on habitat selection of
 capercaillie across Europe. – Biol. Conserv. 244: 108529.