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Evaluating forest management intensity on an umbrella species:
Capercaillie persistence in central Europe
Martin Mikoláš
, Marek Svitok
, Martin Tejkal
, Pedro J. Leitão
, Robert C. Morrissey
Miroslav Svoboda
, Meelis Seedre
, Joseph B. Fontaine
Czech University of Life Sciences Prague, Faculty of Forestry and Wood Sciences, Kamy
´cká 129, Praha 6 – Suchdol 16521, Czech Republic
PRALES, Odtrnovie 563, 013 22 Rosina, Slovakia
Department of Biology and General Ecology, Faculty of Ecology and Environmental Sciences, Technical University in Zvolen, Masaryka 24, 96001 Zvolen, Slovakia
Eawag Swiss Federal Institute of Aquatic Science and Technology, Department of Aquatic Ecology, Centre of Ecology, Evolution and Biogeochemistry, Seestrasse 79,
CH-6047 Kastanienbaum, Switzerland
Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamy
´cká 129, Praha 6 – Suchdol 165 21, Czech Republic
Geography Department, Humboldt-Universität zu Berlin, Unter dem Linden 6, 10099 Berlin, Germany
School of Veterinary and Life Sciences, Murdoch University, Perth 6150, Australia
article info
Article history:
Received 4 January 2015
Received in revised form 1 July 2015
Accepted 3 July 2015
Available online 11 July 2015
Habitat requirements
Anthropogenic threat
Umbrella species
Ecological forestry
Forest management
Deforestation and fragmentation of forests worldwide are negatively impacting biodiversity. The caper-
caillie (Tetrao urogallus) is an endangered umbrella species of montane forests in central Europe. Despite
its status, it has largely been overlooked in forest management planning in the Carpathian Mountains, a
biodiversity hotspot within the European Union. Previous investigations of timber management effects
on capercaillie have shown contradictory results within Europe; habitat loss and fragmentation due to
intensive forest management have been implicated in population declines, while other studies have sug-
gested neutral or positive effects. In Romania, recent changes in forest management have shifted from
extensive, selective logging to intensive clearcutting; this change provides the opportunity to assess
the effects of harvesting on capercaillie numbers across a full range of forest management intensities,
thereby addressing discrepancies in the literature. Across the Southern and Eastern Carpathian moun-
tains from 2009–2011, we used spring counts of capercaillie males at leks to evaluate the impact of forest
management, other human activities, and habitat at two spatial scales – stand (2 ha) and landscape
(300 ha). At the landscape level, the proportion of forest clearcuts and intensity of tourism had signif-
icant negative effects on the number of capercaillie males in the lek. In contrast, low intensity selective
logging had a positive effect at the local stand (lek) level. Large scale (landscape level) forest clear-cutting
had a negative effect on the capercaillie population – areas comprised of clearcuts of 30% reduced male
lek counts by 76%. The protection of intact mature and old-growth forests, and forest management prac-
tices that emulate natural disturbance processes are recommended to support habitat of this critical
umbrella species and associated biodiversity.
Ó2015 Elsevier B.V. All rights reserved.
1. Introduction
Over the past century, global declines in mature forested area
(Hansen et al., 2013) and biodiversity related to habitat loss, frag-
mentation, and overexploitation are causing increased concern
among natural resource managers and conservationists (Wilcove
et al., 1998). Large-scale clear-cutting of forested landscapes has
driven the vast majority of forest species losses (Lamberson and
McKelvey, 1992; Wallenius et al., 2010) and much attention has
been devoted to alternative harvest strategies and associated man-
agement to retain forest species within landscapes (e.g. Franklin
and Johnson, 2012). In areas such as central Europe that histori-
cally have been heavily forested but now have limited and increas-
ingly fewer areas of old-growth forest cover (Mackey et al., 2014),
identifying management impacts and alternatives is a priority.
Here, we use the capercaillie, Tetrao urogallus, to evaluate the
effects of logging old forests on mating habitat selection. The
capercaille is considered an umbrella species within the region
and an indicator of structurally rich forest conditions (Suter
et al., 2002). Capercaillie populations in central Europe have
declined rapidly in recent decades (Storch, 2007a). Identifying
0378-1127/Ó2015 Elsevier B.V. All rights reserved.
Corresponding author.
E-mail address: (M. Mikoláš).
Forest Ecology and Management 354 (2015) 26–34
Contents lists available at ScienceDirect
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forestry practices that may aid in maintaining viable population
levels of this species within forested landscapes are vital to ensure
their persistence in the landscape alongside many other species
commonly represented in these habitat types.
Capercaillie inhabits forests of Eurasia, and they are associated
with extensive natural, old-growth or young open canopy forests,
characterized by high levels of structural heterogeneity, particu-
larly, multistoried tree layers and abundant cover of ericaceous
understory shrubs (Bollmann et al., 2005; Klaus et al., 1989;
Storch, 2002; Suter et al., 2002). Because capercaillie is strongly
associated with open canopy forest and has a relatively large home
range, it is considered an indicator species for high biodiversity and
protection of its habitat will benefit other old-growth forest spe-
cies as well (Pakkala et al., 2003; Suter et al., 2002).
Lek sites, where males display in spring, are particularly vulner-
able to disturbance by humans and may be readily abandoned, as is
common with many species of grouse with this mating system (e.g.
Hess and Beck, 2012; Klaus et al., 1989). Anthropogenic activities,
especially the intensification of forest management, have resulted
in the significant loss and fragmentation of suitable capercaillie
habitat in many parts of western and central Europe (Storch,
2007a). In many European countries, capercaillie populations are
now artificially maintained using release projects, specialized habi-
tat management measures, or predation control (Klaus, 1997;
Marshall and Edwards-Jones, 1998; Siano and Klaus, 2013;
Storch, 2000). Capercaillie is a red-listed species in Annex I of the
EU Birds Directive in most European countries, and it is a specific
designated feature of many of the Natura 2000 sites (Storch,
One of the remaining strongholds of capercaillie populations in
central Europe is the Carpathian Mountains that stretch from the
Czech Republic east to Ukraine and extend to southern Romania.
The Carpathian Mountains possess one of the largest areas of
old-growth and natural forests in Europe with thriving populations
of brown bears (Ursus arctos), lynx (Lynx lynx), grey wolves (Canis
lupus), european bison (Bison bonasus)(Veen et al., 2010), and, his-
torically, a stable and self-sustainig capercaillie population.
Historic land uses, such as grazing and selective logging, main-
tained habitat conditions suitable for capercaillie (Hancock et al.,
2011; Klaus et al., 1989). However, management practices have
changed in the last few decades, with more large scale clearcuts
and associated landscape fragmentation taking place, mainly due
to new post-communist forest restitution laws (privatization of
forest lands) and increasing accessibility by new forest roads
(Knorn et al., 2012a,b).
Habitat loss and fragmentation related to logging activities have
been shown to negatively impact the reproductive success of
capercaillie in boreal forests (Lakka and Kouki, 2009). Similarly,
in western and central Europe, a decline of capercaillie populations
also has been linked to habitat loss through fragmentation and log-
ging (Storch, 2007a). In contrast, recent evidence from boreal for-
ests indicates that the capercaillie is relatively tolerant to
changes in forest management regimes and populations will per-
sist in the long term, even in landscapes with large-scale clearcut-
ting (Miettinen, 2009; Wegge and Rolstad, 2011). However,
capercaillie distribution in boreal forests is continuous and not as
fragmented as in other areas of Europe (Storch, 2007a), and boreal
forest regeneration patterns and dynamics is different compared to
temperate regions of Europe.
Given clear declines of capercaillie associated with intensifica-
tion of forest management over the last two decades, the main
objective of this study was to identify the most important predic-
tors influencing capercaillie male numbers in the leks in the
Southern and Eastern Carpathians. We focused on stand and land-
scape features surrounding lek centres where mating occurs
because they are critically important for sustaining local
populations (Miettinen et al., 2005; Picozzi et al., 1992; Saniga,
2003). Specifically, we were interested in how human land use,
intensity of forest management, habitat fragmentation, and loss
of suitable habitat affect capercaillie abundance at the display
grounds. Outcomes from this study highlight threats to capercaillie
and identify forest management practices compatible with conser-
vation goals.
2. Methods
2.1. Study area
Across the Southern and Eastern Carpathians within Romanaia,
we sampled forests of 11 separate mountains. The potential size of
suitable habitats (mountain forests with elevation >1000 m above
sea level) was estimated on 190,113 ha; total area of all studied lek
centres (1 km radius around the lek centres) was 6594 ha. The cli-
mate of Romania ranges from temperate to continental, and cold
winters and high precipitation are typical for mountainous areas.
The mean winter temperature is 5.2 °C with mean winter precip-
itation of 355 mm, while mean summer temperature is 13.9 °C and
summer precipitation of 1095 mm in the study area (Toader and
Dumitr, 2005).
2.2. Capercaillie population in the study area
Based on hunting surveys across Romania, the total population
of Capercaillie was estimated to be 10,000 birds as of 2007
(Storch, 2007b). During our the study period, hunting of capercail-
lie was legal in Romania; however, since 2012, hunting of caper-
caillie has been prohibited, although ongoing illegal hunting may
still have serious effects on capercaillie populations in some
regions. The lek centres studied were located at altitudes ranging
from 1320 to 1722 m above sea level. The prevalent vegetation
type was Norway spruce (Picea abies (L.) Karst.) forest (86%), mixed
European larch (Larix decidua Mill.)-Norway spruce forest (9.5%),
and mixed Norway spruce-Silver fir (Abies alba Mill.)-European
beech forest (Fagus sylvatica L.) (4.5%).
2.3. History of forest management in the study area
The capercaillie habitats in the Carpathians are mostly high ele-
vation natural forests with old-growth characteristics, such as
large amounts of dead wood, elevated root plates, and
multi-cohort open canopy stands (see the Appendix). Only 9% of
the lek centres occurred in areas of naturally regenerated open
canopy stands (60 years old) resulting from abandonment of
grazing of montane pastures. In the past, all stands were difficult
to access and forest management was predominantly selective
single-tree or group logging made by the shepherds who used
the surrounding mountain pastures during the summer (Huband
et al., 2010). Forest management practices changed considerably
in the studied area after the collapse of communism in 1989.
New forest roads were built into formerly inaccessible areas and
large areas of state forest were restituted to prior owners resulting
in increased forest harvesting at large spatial scales (Griffiths et al.,
2014; Knorn et al., 2012a,b). In addition, some forested areas were
officially categorized as pastures, thus enabling owners to make
large clearcuts without any control, and illegal logging has
occurred during the post-communist era. Extensive clearcutting
forestry has also occurred in protected areas, such as national
parks. Based on remote sensing data (Landsat imagery; Table 1,
Griffiths et al., 2014), in our study plots the mean percentage of
clearcuts after 1990s in protected areas is higher (24.6%), com-
pared to unprotected areas (16.4%). Based on the forest ownership
M. Mikoláš et al. / Forest Ecology and Management 354 (2015) 26–34 27
data (Abrudan, 2012) in our study plots, 43% were private and 57%
owned by state. For the whole of Romania (as of early 2013), over
4.4 million hectares of state, public, and private forest lands were
administered by state and experimental forest districts, with a fur-
ther 1.7 million hectares of forest land administered by private for-
est districts (Marinchescu et al., 2014). It is evident that changes in
ownership have resulted in changes in forest management and
structure across multiple scales (Griffiths et al., 2014; Knorn
et al., 2012a,b)
2.4. Data sampling
2.4.1. Study design
Clearcutting has been widely documented to lead to local extir-
pation of capercaillie (Storch, 2007b). Our objective was not to doc-
ument population declines, but rather to identify forest practices
that would permit persistence of capercaillie. Therefore, we sam-
pled forest conditions representing a range of no harvest to partial
harvest within the known range of capercaillie. Using capercaillie
distribution and density maps provided by the Forest Research
and Management Institute of Romania (ICAS), localities with the
highest capercaillie densities across 11 mountain ranges were
intensively surveyd in a 1 km radius area (314 ha), which was con-
sidered to be the average territorial area used by capercaillie males
during the lekking period (Storch, 1995). We identified 21 lek cen-
tres in Fa
(n= 4), Rodnei (n= 4), Harghita (n= 3), Maramuresß
(n= 3) Piatra Craiului (n= 1), Bucegi (n= 1), Diham (n= 1), Prisciu
(n= 1), H^
asßmasß(n= 1), Ca
˘limani (n= 1), and Piatra Mare (n=1)
(Fig. 1.).
2.4.2. Data collection
Capercaillie males gather in lek centres to display and compete
for females; within display grounds, males establish display terri-
tories spaced 50 m apart. Counting of males at lek centres is a
widely used technique across many species of grouse to monitor
population trends (Miettinen et al., 2005; Picozzi et al., 1992;
Saniga, 2003). During the daytime period, they remain within a
radius of approximately 1 km of the lek centre (Storch, 1995).
Plot locations, defined by lek centres, were determined by the posi-
tion of the alpha capercaillie male; GPS coordinates recorded after
birds finished displaying during each visit. These lek centres are
usually located in the same sites annually and may be used for sev-
eral decades (Klaus et al., 1989). Lek surveys were conducted from
March to May during 2009–2011 with two visits per season; the
maximum counts were used in the analyses. Surveys were per-
formed from 03:00 to 09:00, and all observed or heard capercaillie
males were recorded. During the day we returned to look for signs
and display stances, which helped to clarify the capercaillie male
numbers in the leks.
2.4.3. Environmental data and scale consideration
To understand drivers of capercaillie abundance we collected
data on three principal types of data: habitat, forest management,
and human activity, excluding forest management activities
(Table A1). Data were restricted to stand scale and landscape scale;
stand scale measurements were defined as an 80 m radius circular
plot (2.1 ha), and landscape scale as a 1 km radius area (314 ha) to
evaluate broader scales impacts, such as forest management and
intensity of tourism. Landscape scale considerations were also
defined by distance based variables for habitat or human activity
variables (e.g. distance to the closest building, water spring, etc.).
2.4.4. Habitat measurements
Habitat characteristics were measured in the lek centres during
the summer months. We used an extensive list of site characteris-
tics to evaluate possible lek centre preferences in the
under-researched part of the species distribution in Southern and
Eastern Carpathians. The variables recorded included topography,
surface type, main canopy characteristics, understorey, ground
vegetation, dead wood, soil, habitat use by large herbivores, human
land use, type of forest management, and the landscape; for a com-
plete listing, see Table A1.
Table 1
Forest extent and losses in each study plot (N= 21, plot size = 314 ha) with mean values (italicized) representing subregions of the Southern and Eastern Carpathians in Romania
2009–2011. For every study plot the maximum number of capercaillie males lekking in the display ground (centre of the study plot) and maximum number of females recorded
during the spring season are reported. The top portion of the table shows the values in study sites with no protection regulations while the bottom portion shows the protected
study sites.
1985–1990 1990–2010 1990–2010 1990–2010 Conservation status Male numbers Female numbers
Clearcut (ha) Forest (ha) Clearcut (ha) Forest (ha) Clearcut (%) Average forest loss
0 314.1 12.96 301.14 4.1 16.40% No protected 7 5
0 239.85 6.3 234.54 1.7 4 2
0 240.57 33.21 207.36 10.6 2 2
3.06 304.65 178.47 129.24 55.8 2 0
0 135.09 9.27 125.82 331
0 283.32 45.81 238.23 14.4 1 2
1.89 267.93 6.48 263.34 1.5 3 3
1.26 291.42 108.18 184.5 34 1 1
4.95 253.62 75.51 183.06 22.5 1 1
1.24 258.95 52.91 207.47 16.4
21.78 165.69 19.62 167.85 0.7 21.14% Protected 3 1
0 303.03 135.72 167.31 43.2 4 2
9 237.42 3.6 242.82 1.7 1 1
1.44 281.34 123.57 159.21 38.9 3 1
0 266.85 225.81 41.85 71.6 1 1
0 212.22 119.97 92.61 38.1 1 2
8.19 224.19 77.04 155.34 21.9 2 1
0 277.65 5.67 272.88 1.5 2 1
61.47 200.34 3.06 258.75 18.6 2 3
7.02 130.23 51.39 85.86 14.1 2 1
17.01 297.36 132.48 181.89 36.8 6 8
1.08 258.03 27.99 231.12 8.6 9 4
10.58 237.86 77.16 171.46 21.14
28 M. Mikoláš et al. / Forest Ecology and Management 354 (2015) 26–34
2.4.5. Forest management
Forest management activities were evaluated at the stand and
landscape levels. At the stand scale, selective logging intensity
was measured based on percent canopy removal and presence of
forest roads within 80 m plot radius (2.1 ha). At the landscape
scale, clearcut estimates were based on the proportion of the
1 km radius (314 ha) plot area that was clearcut within the previ-
ous five years (since 2005) and larger than one ha. A detailed list of
variables and an explanation of variable scales are provided in
Table A1 and Table 2, respectively.
2.4.6. Impact of (non-logging) human activity
To evaluate human land use intensity, activities were defined
based on maps and direct enquiries of local and regional experts
(administrators of national and natural parks, forestry administra-
tors, and local shepherds), similar to Rösner et al. (2013). Every
activity was classified on a scale from 0 to 5 to define intensity,
with ‘0’ being the least intensive and ‘5’ being the most intensive
(Table 2). The tourist activity was evaluated for the peak tourist
period that included weekends during the winter/spring period;
it was based on the number of tourists who visited the 314 ha plot.
Fig. 1. Locations of the studied lek centres.
Table 2
Detailed description of the scales of measured variables.
01 2 3 4 5
Intensity of tourism (314 ha
No tourism <10 person/day 10–50 people/day 50–100 people/day 100–150 people/day >150
Selective logging intensity
(2.1 ha plot)
Presence of a forest road,
no cuttings in the lek
Cuttings in the lek
centre <1%
Cuttings 1–15% Cuttings 15–30% Cuttings >30%
Intensity of grazing (314 ha
No grazing Grazing of <15 standard
livestock units irregularly
Grazing of 15–150
livestock units
Grazing <15
livestock units
Grazing of 15–150
livestock units regularly
More than
150 livestock
Intensity of hunting (314 ha
No hunting Legal hunting of 1
capercaillie per 15 years
Legal hunting of 1
capercaillie per
10 years
Legal hunting of 1
capercaillie per
5 years
Legal hunting of more
than 1 capercaillie per
5 years
Illegal hunting
Spatial distribution of
vegetation clustering (ID)
(2.1 ha plot)
Obscure clusters Small clear clusters Large clear clusters Small orientated clusters Large
M. Mikoláš et al. / Forest Ecology and Management 354 (2015) 26–34 29
The number of tourists was based on information from
administrators of national and natural parks and tourist centre
administrators (e.g. ski-lift companies, mountain cottages owners).
Distance-based variables, such as distance to the closest buildings,
and distance to closest road, were also used to evaluate human
activity and presence.
2.5. Statistical analyses
Because a large numbers of explanatory variables were mea-
sured for a relatively small sample size (n= 21), the number of
explanatory variables was reduced prior to analyses to avoid prob-
lems with collinearity (Dormann et al., 2013). Principal component
analysis (PCA) on correlation matrices of landscape characteristics
(12 variables), the cover of individual species in the tree layer (7
variables), the shrub layer (11 variables), and the herb layer (27
variables) was used to reduce the dimensionality. The broken stick
model was used to identify the number of non-trivial principal
components (Jackson, 1993). This selection process resulted in
one principal component (PC) for the landscape characteristics,
two PCs for the tree layer, two PCs for the shrub layer, and four
PCs for the herb layer (see Table A2).
The relationships between capercaillie numbers and environ-
mental characteristics were analysed using generalized linear
models (GLM; McCullagh and Nelder, 1989). In addition to the
latent variables described above, the remaining variables (see
Tables A1 and A2) were then combined to form a list of candidate
predictors. An exhaustive best-subset regression procedure was
employed in search of the most parsimonious model (McLeod
and Xu, 2009). Poisson distribution and logarithmic link-function
were used within GLMs to relate numbers of males in the lek cen-
tres with the predictors. The Bayesian information criterion (BIC)
was used for model selection. Due to the limiting number of
degrees of freedom, only those models with a maximum of 5
explanatory variables were considered in the analyses.
Parameters of the final model were tested using likelihood ratio
tests (Crawley, 2007), and the model fit was assessed using
McFadden’s (pseudo) determination coefficient (McFadden,
1973). Standardized regression coefficients were calculated to
facilitate direct comparisons across significant predictors, regard-
less of differences in the scale of the predictors. The relative impor-
tance of explanatory variables on capercaillie abundance was
assessed by variation partitioning (Borcard et al., 1992). The
deviance explained by each variable was expressed as a percentage
of the total variation, represented by the deviance of a null model.
Partial regression plots and effect plots were constructed to depict
partial relationships in the final model (Fox, 2001). Partial regres-
sion plots allowed us to visualize the effect of each predictor after
adjusting for all the other predictors in the final model. Effect plots
display fit for each partial relationship while the other predictors
are fixed at mean values. All analyses were performed in R (R
Development Core Team 2010) using the bestglm (McLeod and
Xu, 2011) and vegan (Oksanen et al., 2011) packages.
3. Results
Active capercaillie leks were not found within recent clearcuts
and they were not detected where clearcutting exceeded 62% of
the surrounding landscape (314 ha) (Fig. A1). Almost all lek centres
were situated in forests with old-growth characteristics and lim-
ited anthropogenic influence (see Table A1). Only two lek centres
were situated in younger forests, but these were in fact abandoned
pastures and not clearcut areas. The average forest cover in the
314 ha plot was 187 ha (60%), with a range between 79 ha (25%)
and 301 ha (96%); the remaining areas were covered by mountain
pastures or clearcuts. The average number of capercaillie males
counted in the lek centres was 2.9 (SD = 2.15), and the average
number of females was 2 (SD = 1.8) (see Table 1.)
The best model to explain the number of male capercaillie at lek
centres contained three variables: the proportion of clearcuts at
the landscape scale and intensity of tourism negatively influenced
male capercaillie numbers, but selective logging intensity at the
stand scale had a positive effect (Table 3). The overall model signif-
icantly explained 62.8% of the deviance (
= 17.27, p< 0.001), and
partial regression plots indicated the model provided a reasonable fit
to the data (Fig. 2a–c). Based on standardized regression coefficients,
the effect size of landscape scale clearcuts was largest. Variation par-
titioning indicated that >37% of the deviance in male numbers could
be explained by the proportion of clearcuts; holding the effect of
other variables constant, clearcuts of 30% reduced male lek counts
by more than four times (Fig. 2d). The deviance attributable to tour-
ism and selective logging intensity amounted to 31% and 20%,
respectively. Differences between no (0) and intensive (5) tourism
and selective logging indicated a 4.4-fold decrease and a 3.7-fold
increase in male lek counts, respectively, when other factors were
held constant (Fig. 2e–f).
4. Discussion
Of all the studied variables, three anthropogenic factors had the
highest influence on capercaillie numbers: the proportion of clear-
cuts, intensity of tourism, and selective logging. Romania has expe-
rienced massive socio-economic and institutional change over the
past 25 years (Knorn et al., 2012a,b) that has impacted ownership
and human land use, such as forestry and tourism. Negative effects
of emerging land use (increased forest exploitation and tourism)
were evident, while historic forest practices were positively related
to capercaillie numbers. The average capercaillie male numbers per
lek were similar to numbers detected in other regions, where long
term declining population trends were detected (e.g. Zawadzki and
Zawadzka, 2012; Saniga, 2012).
4.1. Capercaillie and forest harvesting
The effects of forest harvesting on capercaillies depend on the
intensity and extent of harvesting practices (Klaus, 1991). The
selective logging intensity in the lek centres had a positive effect
on capercaillie male numbers. In dense managed stands, selective
logging reduces canopy cover in a manner similar to small-scale
natural disturbance processes, which makes the forest canopy
more open and increases structural heterogeneity of the stand
(Broome et al., 2014; MacMillan and Marshall, 2004).
Multistoried tree layers with gaps and abundant cover of erica-
ceous understory shrubs may improve summer forage and cover
from predators for capercaillies. Although our results did not show
a significant relationship between number of capercaillie males
and bilberry cover, the capercaillie habitats typically contained
extensive patches of bilberry; based on other studies, we do know
Table 3
Parameters of the final GLM model showing relationships between the number of
capercaillie males in the lek centres and the proportion of clearcuts, intensity of
tourism, and intensity of forest management. Standardized regression coefficients (b),
regression coefficients (b), standard errors (se), test statistics (
) and probabilities (p)
are displayed.
Parameter bbSe
Intercept 2.036 0.187 44.54 <0.001
Proportion of clearcuts 0.41 0.048 0.009 14.32 <0.001
Intensity of tourism 0.22 0.296 0.071 9.86 0.002
Selective logging intensity 0.24 0.262 0.083 5.35 0.021
30 M. Mikoláš et al. / Forest Ecology and Management 354 (2015) 26–34
that bilberry is an important habitat component (eg. Wegge and
Rolstad, 2011; Hancock et al., 2011; Storch, 2002, 1993).
At the landscape scale, the proportion of clearcuts surrounding
the lek centres had an exponential negative effect on capercaillie
numbers (Fig. 2d), as suitable habitats are lost and fragmented
by clearcuts. The relationship between habitat fragmentation and
extinction has been demonstrated to be highly non-linear
(Fahrig, 2003), thus, the presence of clearcuts also has broader
implications to population and metapopulation dynamics through-
out the region.
Our results are in contrast with the findings of studies con-
ducted in the boreal zone (Miettinen, 2009; Wegge and Rolstad,
2011); they observed that capercaillie were tolerant to clearcutting
across the landscape because capercaillie were also able to use
open canopy middle-aged plantations (>30 years old) with bilberry
ground cover. The findings of these studies cannot necessarily be
applied to central Europe or the Southern and Eastern
Carpathians, which are all outside the boreal zone. Capercaillie dis-
tribution in central Europe is very fragmented compared to the
boreal zone; capercaillie persist here in patchy populations embed-
ded in a mountainous landscape (Storch, 2007a). In fragmented
conditions of central Europe it is very difficult to maintain viable
capercaillie populations, which require ca. 250 km
and an esti-
mated 470 interacting capercaillie individuals (Grimm and
Storch, 2000). Inter-patch dispersal is very important for the per-
sistence of capercaillie, thus, high habitat connectivity is important
for metapopulation dynamics. In the Carpathians, suitable caper-
caillie habitats are a mere small ’habitat band’ of coniferous dom-
inated forest situated between mountaintops and the deciduous
forests of lower altitudes. In case of intensive clearcutting, alterna-
tive forest nearby which represents suitable capercaillie habitat is
thereby naturally limited. When stepping stones are lost and habi-
tat connectivity is disrupted by clearcuts on large spatial scales, as
in this study, migration of individuals between populations could
be severely limited and population persistence may be threatened
because small isolated populations are unlikely to survive
(Segelbacher et al., 2003). These factors has lead to extinction debt
in other small and isolated metapopulations (Pullin, 2002). In addi-
tion, the typical management practices in central Europe do not
enable creation of open canopy forest structure suitable as caper-
caillie habitat (Bollmann et al., 2005). Plantation establishment
after clearcutting is mandatory in central Europe; the result is very
dense forest canopies with very little ground vegetation, particu-
larly critical bilberry cover (Vaccinium myrtillus L.), which provides
food for adults, invertebrates for chicks, and hiding and thermal
cover (Hancock et al., 2011; Storch, 1993).
The negative landscape level effect of large clearcuts on caper-
caillie numbers was significant and outweighed the positive effects
of selective logging intensity. These clearcuts cover large areas and
might almost completely remove the narrow spruce forest vegeta-
tion belt in some areas. Unlike smaller clearcut patch harvesting
that creates fine grain forest fragmentation that may be suitable
for capercaillie in the boreal forests (Sirkiä et al., 2011), large clear-
cuts cause long-term loss of habitat with no alternative options of
suitable habitats in the surrounding forests where the birds could
migrate. Increased harvesting using clearcuts practices are largely
related to restitution laws implemented after the collapse of com-
munism in 1989; forest harvesting increased sharply in two waves
around 1995 and 2005 (Knorn et al., 2012a). Clearcuts recorded in
our study (younger than 5 years) in the capercaillie habitats coin-
cide with the second wave of harvesting after 2005. The area of
suitable habitats is declining and becoming more fragmented as
a result of large-scale clearcuts in the Carpathians, with little dif-
ferentiation in forest management practices between protected
or non protected areas (Knorn et al., 2012a).
4.2. Capercaillie and tourism
The negative effect of intensive tourism (e.g. ski resorts) on
capercaillie and other bird populations has been reported in many
regions (e.g. Moss et al., 2014; Rösner et al., 2013; Thiel et al.,
2011). Human disturbance may influence metapopulation dynam-
ics and contribute to genetic impoverishment in small populations
(Moss et al., 2014). For example, collisions with ski-lift cables may
Number of males
10 20 30 40 50 60 0 1 2 3 4 5 0 1 2 3 4 5
Proportion of clearcuts (%) Intensity of tourism Selective logging intensity
e (Prop. of clearcuts | o.v.)
e (Number of males | o.v.)
e (Intensity of tourism | o.v.)
e (Sel. logging intensity | o.v.)
(b) (c)
(e) (f)
Fig. 2. Partial regression plots (a, b, c) and effect plots (d, e, f) demonstrating the multivariate relationship between number of males in the lek centres and the proportion of
clearcuts (a, d), intensity of tourism (b, e) and selective logging intensity (c, f). Lines represent partial regression slopes (a, b, c) and partial fitted relationships holding the
other variables (o.v.) constant at their means (d, e, f). Ninety-five percent confidence intervals are shown in grey.
M. Mikoláš et al. / Forest Ecology and Management 354 (2015) 26–34 31
increase capercaillie mortality. Intensive tourism can negatively
influence brood success because it increases levels of the stress
hormone corticosterone, which influences reproduction and sur-
vival (Thiel et al., 2011). Also, areas frequented by people have
increased carrying capacity for a family of avian predators – the
Corvidae; ravens, crows and jays favour human inhabited areas
(Storch and Leidenberger, 2003). Recent increased use of snowmo-
biles and off-road vehicles concentrated near tourist recreation
areas may have the most negative effects, as they may cause seri-
ous yearlong disturbances to the capercaillie in many regions. To
offset the effects of tourism on capercaillie populations, sufficiently
large habitat patches that provide good hiding cover and buffers
from touristic areas and roads should be established and main-
tained (Newsome and Moore, 2012). Increased use of selective har-
vesting can help to achieve this. Further, by planting dense
vegetation bordering frequented tourist paths, the probability of
people leaving marked trails and disturbing capercaillies would
be reduced (Coppes and Braunisch, 2013).
4.3. Old growth forests as refuge
Old-growth forests are the primary habitats for capercaillies
(Klaus et al., 1989) and it was shown already for the Carpathians
as the main capercaillie habitat type (Saniga, 2003). The habitat
characteristics of most of the studied lek centres were typical of
old-growth forests – large amounts of dead wood, elevated root
plates, multi-cohort open canopy stands, etc. (Table A1). The struc-
ture of these forests is a result of natural disturbance regimes char-
acterized by windthrows and bark beetle outbreaks, which are
usually infrequent, moderate- to high-severity disturbances that
influence forest structure across all spatial scales – tree, stand,
and landscape (Svoboda et al., 2014; Trotsiuk et al., 2014). These
disturbances create canopy gaps and forest edges of different sizes
(Fraver and White, 2005), which provides suitable habitats for
capercaillie. These types of stands are currently just a small frac-
tion of the landscape in central Europe (Wesolowski, 2005), thus,
they play a key role for the preservation of capercaillie populations
and many other species in the Carpathians. There has been a clear
trend in the large-scale destruction of mountain spruce forests,
including old-growth and natural forests across the whole
Carpathian region over the past few decades (Griffiths et al.,
2014; Knorn et al., 2012a,b; Kuemmerle et al., 2009, 2007), and
the natural mountain forest community is endangered. The
long-term survival of the species is therefore reliant on the viabil-
ity of core areas to serve as refuges.
5. Conclusions and implications for forest management
Our study indicates that extensive human land use, such as low
intensity selection harvesting, can have positive effects on caper-
caillie, but large-scale clearcutting and intensive tourism can also
have very negative effects. Measures to conserve the umbrella spe-
cies capercaillie will benefit a wide range of other forest species
and better preserve a wide range of ecosystem functions and ser-
vices (Balvanera et al., 2006; Suter et al., 2002). Our results indicate
that even protected areas do not ensure the protection of threat-
ened species and their habitats in the Carpathian region
(Table 1). This can only be changed if the priority in protected areas
is the conservation of biodiversity and prioritization of
non-extractive ecosystem services rather than timber production
as in typical commercial forests.
Conservation and forest management goals should be based on
a multi-scale approach. Commercial forest management in rele-
vant areas should be modified to emulate natural disturbance pro-
cesses across multiple scales. With single-tree selection, group
selection, conversion of spruce to mixed species, increasing large
snag densities, and creating a multi-layered canopy at the stand
level, foresters can accelerate the development of suitable natural
forest habitats (Franklin et al., 2002). Sufficient areas (cca
250 km
) of quality habitat are necessary foundations for viable
capercaillie populations (Grimm and Storch, 2000), thus, manage-
ment planning for viable populations should be in accordance with
broader relationships at the landscape scale to ensure a
sufficiently-sized mosaic of suitable habitats and connectivity
between habitat patches (Graf et al., 2009; Segelbacher et al.,
2003). To ensure the long-term survival of capercaillie populations
in the Carpathians, it is necessary to conduct further assessments
of the suitability of existing capercaillie habitats (e.g. create a habi-
tat suitability model) and identify the optimal extent of suitable
habitat and its connectivity (Braunisch and Suchant, 2008). The
habitat suitability model should be adapted regionally, because
species – habitat relationships may differ between regions, due
to different site conditions, vegetation types, and successional pro-
cesses (Graf et al., 2005), as exemplified by differences in capercail-
lie habitat use in Norway and central Europe. Management at the
landscape scale should include the protection of old-growth for-
ests, the restriction of fragmentation and large-scale deforestation,
to ensure a more ecologically sustainable forestry model in central
This study was supported by Czech Science Foundation Project
(GACR 15-14840S) and Czech University of Life Sciences, Prague
(CIGA No. 20154316) and also by German Aerospace Centre –
Project Management Agency (P. J. L., grant number 50EE0949).
We thank Ivana Kalafusová, Ovidiu Ionescu, Tudor Stancioiu, G.E.
Predoiou, the administrations of Natural Park Maramuresß,
National Park Rodnei, National Park Piatra Craiului, National Park
˘limani, Natural Park Bucegi, National Park Ha
and Forests
of Lunca Bradului for their information and help in collecting data.
We thank Ilse Storch and Mario Quevedo for revising an early ver-
sion of the manuscript.
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... Capercaillie extinctions and population declines are both associated with habitat loss and fragmentation, as well as intensified land-use by people (e.g. in sport, tourism and recreation, and forest management) (Storch 2007(Storch , 2013Thiel et al. 2011;Moss et al. 2014;Coppes et al. 2017Coppes et al. , 2018. The major reasons for changes in the habitat of the species are considered to relate to the development of commercial forestry, where large areas are clear-felled (Saniga, 2003;Wegge and Rolstad, 2011;Mikoláš et al., 2015;Kämmerlea et al. 2020). The remaining areas of old-growth forests are too small and isolated, and extensive areas of young and middle-aged stands are characterised by unsuitably high densities of trees (Sirkiä et al. 2011). ...
... The remaining areas of old-growth forests are too small and isolated, and extensive areas of young and middle-aged stands are characterised by unsuitably high densities of trees (Sirkiä et al. 2011). In general, the negative influences of forestry manifest mostly in the destruction of lekking sites along with the surrounding territories occupied by males, as well as, partly, in overall habitat loss and forest fragmentation (Rolstad and Wegge 1987;Miettinen et al. 2010;Wegge and Rolstad 2011;Mikoláš et al. 2015). Changes in the structure of forest landscape, induced by forest management, affect the distribution of leks and the area occupied by the capercaillie (Angelstam 2004;Zizas et al. 2017). ...
... In the Carpathian Mountains, selective logging at low intensity was reported as affecting the population of the local capercaillies in a positive way. In contrast, the proportion of forest clear-cuts in an area as well as the intensity of tourism are both seen to exert a significant negative influence on the numbers of males present at leks (Mikoláš et al., 2015). ...
Full-text available
Background Forest management affects the habitat conditions for many forest-dwelling species. Among them, the capercaillie ( Tetrao urogallus ) is a rare forest grouse inhabiting old, mature forests. We compared the structure of forest habitat among 9 active and 9 abandoned leks in the Augustów Forest (North-Eastern Poland), within a radius of 1 km of the leks, defined as the Key Areas for the capercaillie in lowland temperate forest. Habitat measurements were conducted on 1779 circular plots. Assessments made on all plots related to 13 habitat variables measured or noted in the field, including stand structure, canopy closure, stand developmental stage, percentage of Scots pine ( Pinus sylvestris ), soil fertility and soil moisture, the share of undergrowth, the cover of shrubs, the cover of bilberry ( Vaccinium sp.), and the presence of certain habitat elements important to the capercaillie. Results To compare the still-occupied and the abandoned KAs for the capercaillie, a logistic regression model was developed. The variables best explaining differences between these two categories were: the occurrence of undergrowth layers, canopy closure in the second canopy layer, and stand age. According to the model, with the increase of the shrub-layer cover as well as the density of trees, the probability of the presence of the capercaillie decreased. The capercaillie in the area of the Augustów Forest occupy mainly dry and poor, middle-aged, pine-dominated forests, with a moderate extent of stand canopy closure and only weakly-developed layers of undergrowth. Conclusions The filling-in of mature stands with sub-canopy trees and shrubs (the process which is stimulated by climate change and site eutrophication) causes structural changes, which are unfavourable to the capercaillie. This might explain why in the course of the recent decades the capercaillie has abandoned the oldest stands, distinguished by the presence of bigger shares of undergrowth. The capercaillie has shifted to younger stands, which reveal a lesser extent of canopy closure and a more limited development of understorey vegetation.
... Specialization on food resources depends on local conditions, where only a few plants are important diet items throughout the capercaillies' range (Sedinger, 1997). Traditionally, capercaillie diet studies were based on direct observations during foraging events (Gustafsson, 2008), but capercaillies are highly susceptible to human disturbances making direct observations challenging and detrimental to their well-being (Duriez et al., 2007;Mikoláš et al., 2015). Another method commonly used is the microhistological identification of plants through analysis of crop contents (Borchtchevski, 2009;Wegge & Kastdalen, 2008). ...
... Alternatively, this plasticity in their diet could imply that good habitat quality with access to a diverse array of food resources might be an important factor in their survival. As an umbrella species, protection of the capercaillies' habitat would also indirectly benefit other taxa living in the same habitat such as wolves, lynxes, owls, and woodpeckers (Mikoláš et al., 2015;Suter et al., 2002). Hence, conservation strategies targeted at the protection of the capercaillies' habitat has a broader conservation implication on the diversity found within these habitats. ...
Full-text available
Conservation strategies centered around species habitat protection rely on species’ dietary information. One species at the focal point of conservation efforts is the herbivorous grouse, the western capercaillie (Tetrao urogallus), which is an indicator species for forest biodiversity conservation. Non-molecular means used to study their diet are time-consuming and at low taxonomic resolution. This delays the implementation of conservation strategies including resource protection due to uncertainty about its diet. Thus, limited knowledge on diet is hampering conservation efforts. Here, we use non-invasive environmental DNA (eDNA) metabarcoding on DNA extracted from faces to present the first large-scale molecular dietary analysis of capercaillies. Facal samples were collected from seven populations located in Norway (Finnmark, Troms, Trøndelag, Innlandet) and France (Vosges, Jura, Pyrenees) (n = 172). We detected 122 plant taxa belonging to 46 plant families of which 37.7% of the detected taxa could be identified at species level. The average dietary richness of each sample was 7 ± 5 SD taxa. The most frequently occurring plant groups with the highest relative read abundance (RRA) were trees and dwarf shrubs, in particular, Pinus and Vaccinium myrtillus, respectively. There was a difference in dietary composition (RRA) between samples collected from the different locations (adonis pseudo F5,86 = 11.01, r² = 0.17, p = 0.001) and seasons (adonis pseudo F2,03 = 0.64, r² = 0.01, p = 0.036). Dietary composition also differed between sexes at each location (adonis pseudo F1,47 = 2.77, r² = 0.04, p = 0.024), although not significant for all data combined. In total, 35 taxa (36.8% of taxa recorded) were new capercaillie food items compared with existing knowledge from non-molecular means. The non-invasive molecular dietary analysis applied in this study provides new ecological information of capercaillies’ diet, improving our understanding of adequate habitat required for their conservation.
... Specialisation on food resources depends on local conditions, where only a few plants are important diet items throughout the capercaillies' range . Traditionally, capercaillie diet studies were based on direct observations during foraging events (Gustafsson, 2008), but capercaillies are highly susceptible to human disturbances making direct observations challenging and detrimental to their well-being (Duriez et al., 2007;Mikoláš et al., 2015). Another method commonly used is the microhistological identification of plants through analysis of crop contents Wegge & Kastdalen, 2008). ...
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Diet information is key when implementing conservation strategies for species habitat protection. Non-molecular methods used to attain herbivore diet information are time-consuming and generally have low taxonomic resolutions. Hence, researchers are limited by the number of individuals that they can study within a short time frame. Advances in high-throughput sequencing technologies overcome these limitations as they allow rapid sequencing of multiple samples in parallel. The species of interest in my thesis is the herbivorous wood grouse, the western capercaillies (Tetrao urogallus). The western capercaillie is a targeted species when carrying out forest protection due to its unique habitat requirements. As this bird is particularly susceptible to anthropogenic disturbances, I used non-invasive environmental DNA analyses of its faeces to study its diet. The first three chapters in my thesis are educational book chapters describing the use of faecal samples in molecular diet studies (Chapter 1), and two high-throughput sequencing techniques used in plant identification; metabarcoding (Chapter 2) and metagenomics (Chapter 3). I explored the advantages and challenges of using these two techniques to reconstruct the western capercaillie’s diet in Chapters 4 and 5. In Chapter 4, I developed an in silico approach to validate metagenomics taxonomic assignment steps for the identification of plant taxa. In Chapter 5, I present the first large-scale capercaillie molecular diet study carried out using metabarcoding. A common issue of these two high-throughput sequencing techniques is the lack of a curated and comprehensive DNA reference database used in the taxonomic identification of sequenced data. As a small but important step forward to overcome this limitation for future plant biodiversity monitoring studies in Denmark, in Chapter 6, I generated plant DNA reference data using genome skimming. These reference data consist of the chloroplast and nuclear DNA sequences of 184 Danish plant species.
... The level 3 ecoregions (EPA, 2006) were used in this study because they appeared to be more appropriate than those at other levels for illustrating the spatialtemporal patterns of forest disturbance intensity mapped in this study. Since the proportion of clear-cut areas to all harvested areas is often used as an indicator of harvest intensity at the regional scale (Mikoláš et al., 2015;Schleeweis et al., 2020;Soutiere, 1979), we also examined the spatial variability of stand-clearing disturbances across states and ecoregions. Stand clearing is defined as no less than 80% basal area removal (Birdsey and Lewis, 2002). ...
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Forest disturbances can have broad impact on the climate, local environment, and the regeneration of the forest ecosystem. The nature and magnitude of such impact is largely driven by disturbance intensity. In this study, by integrating field plot measurements collected by the Forest Inventory and Analysis program with time series Landsat observations, we produced the first set of annual forest disturbance intensity map products quantifying the percentage of basal area removal (PBAR) at the 30-m resolution for the conterminous United States (CONUS) from 1986 to 2015. The derived map products revealed that during the 30-year study period, the annual average PBAR values of all disturbed pixels across CONUS ranged from 66% to 70%, and the proportion of those pixels having stand-clearing disturbances ranged from 40% to 58%. High disturbance intensities were concentrated in the Southeastern states from Texas to Virginia and along the Pacific coast and the Cascades in the West. At the national scale, the annual mean PBAR and proportion of stand clearing area (PSCA) values both appeared to follow second order trajectories, with increasing trends at the beginning, decreasing trends towards the end, and turning points around 2003. Overall, there is a net increase of 2% in PBAR and 3% in PSCA from 1986 to 2015. The temporal trends of PBAR and PSCA were also investigated at state and ecoregion levels, with substantial differences found among many states and ecoregions. While states and ecoregions generally follow second order trajectories, the majority had increasing trends throughout much of the study period, reflecting higher disturbance intensities during the later years compared to earlier years. Large increase (>10%) in PBAR was seen in several states (e.g., Virginia, Arkansas, and Minnesota) and ecoregions (e.g., Northern Minnesota Wetlands); however, large decreases (>10%) in PBAR were not observed in any states, and were seen in only one ecoregion, the Blue Mountains in the southeast. The disturbance intensity maps are available from a web portal of the Oak Ridge National Laboratory Distributed Active Archive Center (ORNL-DAAC) at
... The remnant autochthonous tree populations in the heavily modified Cabo Verde Islands must be no exception to this. Considering the ecological value of scattered trees (Prevedello et al., 2018), future studies should compare their patterns of occurrence with those of other species, taking into account their potential as umbrella-species in the protection of the whole biological community (Mikoláš et al., 2015;Roberge and Angelstam, 2004). In Cabo Verde, the endemic trees also have a huge potential for future reforestation or even afforestation initiatives within the context of the measures against drought, defined as one of the critical environmental issues of the archipelago Romeiras et al., 2016). ...
Climate change is one of the most significant challenges to biodiversity conservation, particularly in dry tropical islands, such as the Cabo Verde archipelago where only three endemic tree taxa occur – Dracaena draco subsp. caboverdeana, Phoenix atlantica and Sideroxylon marginatum – all classified as threatened. The main goal of this study was to predict the possible shifts in the climatically suitable habitat ranges for Cabo Verdean endemic tree species under different climate change scenarios. We applied species distribution models (SDMs) to the available occurrence data, and projected the distribution of the three taxa for 2050 and 2080, according to the expected climate change scenarios. The best models were obtained using the Random Forest algorithm; they showed that, by 2080, the suitable habitat for Dracaena draco subsp. caboverdeana and Sideroxylon marginatum will have decreased by 28% and 34%, respectively; conversely, the suitable habitat will have increased by 59% for Phoenix atlantica, the taxon best adapted to arid conditions. Additionally, Santo Antão is the island where endangered trees are more encompassed by protected areas. Overall, this study contributed with new integrated data to support the design and implementation of a strategic plan to promote the conservation and ecological value of Cabo Verde endemic trees in this climatically vulnerable country.
... However, the effects of clearcutting on Capercaillie can vary, depending on their scale and the indirect effects of other factors, and in some cases seem to be uncertain. For example, a study of the effects of increases in clearcutting in Romania on the Western Capercaillie, found that clearcutting had negative small-scale (lek level) and landscape-scale impacts, with forest areas where 30% was clear-cut showing a reduction in counts of males at leks of 76% (Mikoláš et al, 2015). In contrast low intensity selective logging had a small positive effect. ...
Technical Report
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Annex to Final report under EC Contract ENV.D.3/SER/2017/0002 Project: “Reviewing and mitigating the impacts of renewable energy developments on habitats and species protected under the Birds and Habitats Directives”, Institute for European Environmental Policy, Arcadis, BirdLife International, NIRAS, Stella Consulting, Ecosystems Ltd, Brussels. Download report here:
... Specialisation on food resources depends on local conditions, where only a few plants are important diet items throughout the capercaillies' range (Sedinger, 1997). Traditionally, capercaillie diet studies were based on direct observations during foraging events (Gustafsson, 2008), but capercaillies are highly susceptible to human disturbances making direct observations challenging and detrimental to their well-being (Duriez et al., 2007;Mikoláš et al., 2015). Another method commonly used is the microhistological identification of plants through analysis of crop contents (Borchtchevski, 2009;Wegge & Kastdalen, 2008). ...
Full-text available
Conservation strategies centred around species habitat protection rely on species dietary information. One species at the focal point of conservation efforts is the herbivorous grouse, the western capercaillie ( Tetrao urogallus ). Traditional microhistological analysis of crop contents or faeces and/or direct observations are time-consuming and at low taxonomic resolution. Thus, limited knowledge on diet is hampering conservation efforts. Here we use non-invasive environmental DNA (eDNA) metabarcoding on DNA extracted from faeces to present the first large-scale molecular dietary analysis of capercaillies. Faecal samples were collected from seven populations located in Norway (Finnmark, Troms, Trøndelag, Innlandet) and France (Vosges, Jura, Pyrenees) (n=172). We detected 122 plant taxa belonging to 46 plant families of which 37.7% of the detected taxa could be identified at species level. The average dietary richness of each sample was 7 ± 5 SD taxa. The most frequently occurring plant groups with the highest relative read abundance (RRA) were trees and dwarf shrubs, in particular, Pinus and Vaccinium myrtillus, respectively. There was a difference in dietary composition (RRA) between samples collected from the different locations (adonis F5,86= 11.01, p <0.05) and seasons (adonis F2,03= 0.64, p <0.05). Dietary composition also differed between sexes at each location (adonis F1,47 = 2.77, p <0.05), although not significant for all data combined. In total, 35 taxa (36.84% of taxa recorded) were new capercaillie food items compared to existing knowledge. The non-invasive molecular dietary analysis applied in this study provides new ecological understanding of capercaillies diet which can have real conservation implications. The broad variety of diet items indicates that vegetation does not limit food intake. This plasticity in diet suggests that other factors including disturbed mating grounds and not diet could be the main threat to their survival.
... The present research contributes to the protection of endangered species by mapping the protected area and by identifying illegal logging. Another researcher stated that a dynamic landscape conservation plan and policy decisions are needed to protect biodiversity (Mikoláš et al., 2015). In this context, the present study directly contributed to secure the boundaries by defining the protected area in the landscape. ...
In developing countries like Bangladesh, rapid changes in forest area occurred due to illegal encroachment and it can be reduced with the help of local communities. Researchers have always considered urban expansion as a cause of deforestation, and that is not an exception for the Chunati beat forest. About 50 % of primary (natural) forests have been logged during last 20 years in the reserve. That’s why it becomes essential to assess forest cover to monitor and reduce forest degradation. This paper exhibits a research of forest cover and land use of the hilly area of the Chunati forest cover, Bangladesh by integrating participatory mapping, Geographic Information System (GIS) and remote sensing. The forest cover and land use map were produced by using a participatory mapping approach, where the several complex spatial features are marked and monitored with the help of spatial knowledge of local community and satellite images. The study also demonstrates the degradation of the Chunati forest and the conflicts between humans and nature. About 16 % of well stock forest of Chunati beat was degraded by illegal logging and encroachment inside the reserve forest which are the prime factors that need to be restricted. The Forest Department faced difficulties while carrying out restoration, as the forest area was not demarcated. The maps produced during this research estimate the total area encroached by anthropogenic activities. These maps can help policy makers to monitor the Chunati forest cover which will further help to implement land use policy and forest conservation.
... Capercaillie is a species which is spread across Europe, mainly in the northern countries and Russia (Regnaut 2004). The Carpathians are Europe's largest mountain range (Gurung et al. 2009), and most of the old-growth forests of Europe can be found there (Grodzińska et al. 2004, Mikolas et al. 2015. 52.9% of the total range of the Carpathians is located in Romania (Grodzińska et al. 2004). ...
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Romania holds the most extensive mountain range with old-growth forests, in which both habitat surface and capercaillie (Tetrao urogallus) numbers are ones of the highest in Central and Eastern Europe. While previous genetic studies have found that the individuals located in different European mountain ranges are isolated and have highlighted that the species is declining. Here, we are aiming to assess the genetic structure of capercaillie in Romania by genotyping 137 samples collected in the field with 9 STR markers. Expected heterozygosity was 0.586, whereas observed heterozygosity values were 0.859. Population structure analyses indicated weak population differentiation and suggested that sufficient gene flow exists among individuals sampled in different mountain regions. We did not find evidence for a past genetic bottleneck. Our findings contain important information to wildlife managers to focus conservation efforts in areas such as Curvature Carpathians, which serve as a connectivity corridor to avoid eroding the extent or quality of habitat and to prevent further fragmentation.
Capsule Open forest stands with high levels of sunlight and Bilberry Vaccinium myrtillus cover are important for Capercaillie Tetrao urogallus broods. Aims To study the habitat use by Capercaillie broods in the Black Forest, Germany. Methods Habitat characteristics were mapped at locations where indirect signs and observations of Capercaillie broods were recorded along transects. These were compared to habitat characteristics at random locations along the transects using generalized linear mixed models. Results Capercaillie broods in the Black Forest preferred open forest stands with canopy gaps, long daily sun exposure on the ground and an intermediate cover of Bilberry. Stands with high levels of ground vegetation cover and Mountain Pine Pinus mugo shrubs were preferred by Capercaillie broods, while stands with high levels of regeneration cover were avoided. No effect of the horizontal stand layers, number of basal-branched solitary trees or anthills was found. Conclusions To improve habitats for Capercaillie broods, we advise that there should be active creation of structured open stands and forest gaps in areas with high levels of sun exposure (south-west facing) and where Bilberry or heather dominates the ground vegetation.
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Since 1950, more than 4,800 Capercaillies have been released in the course of 11 release projects in different parts of Germany. Eight projects have been finished, only three are still in progress (Thuringia, Higher Sauerland and Lower Lusatia). In 2012 a new pilot study (translocation of wild birds) was started in Lower Lusatia, which is continued only after a critical assessment. Five out of ten release projects definitely failed (Harz, Ebbegebirge, Odenwald, Rhön, central Black Forest). In Thuringia and Higher Sauerland the currently very small populations are maintained because of continued releases. In northern Black Forest the presence of individuals of the autoch-thonous population masked any effect of the releases. A positve population trend was observed in the Bohemian/Bavarian Forest, but that increase can not without doubt be attributed to the release experiment. The release of birds reared in captivity failed to be a successful method. Those birds suffered from physiological and ethological deficiencies such as insufficient predator detection, insufficient development of organs and muscles, reduced digestive ability (non-typical characteristics of digestive tract and microbial composition within caecum) and abnormal behaviour (e.g. aggressive males and tame birds), leading to very high mortality. Despite enormous efforts the rearing of Capercaillies qualifying for living in the wild proved to be challenging. Unless succeeding in developing appropriate rearing and training methods, which enable to get viable birds regarding digestion and behaviour, further releases of captive-reared Capercaillies appear to be useless and should not be started. Translocation of capercaillie caught in the wild gave much better results. Nevertheless, success can be expected only in large areas of adequate habitat quality supporting a population of at least 100 individuals. Supporting a metapopulation system instead of a single isolated remnant population is recommended.
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The aim of this study is to describe the status and evolution of forest administration in Romania in terms of forest regime, as well as to highlight the most frequent problems and common expectations of forest district managers. Underlying the presented results are an analysis of the compiled statistical indicators used in Romanian forestry and the outcome of a sociological survey conducted on a sample of 345 forest district managers. In early 2013, over 4.4 million hectares of state, public and private forest land were administered by state and experimental forest districts, and over 1.7 million hectares of forest land, other than stare-owned, by private forest districts. Note that approximately 0.36 million hectares (over 5% of Romania's forest area) are not in the administration of specialized units, contrary to the legal provisions. The most frequent problems faced by forest district managers arise in relation to the owners of forests or are caused by illegal logging. This study is a contribution to making the concrete problems faced by foresters and especially the structure and ownership related characteristics of forestland the driving force of legislative changes in the forestry sector.
The aim of this study is to describe the status and evolution of forest management in Romania in terms of forest regime, as well as to highlight the most frequent problems and common expectations of forest district managers. Underlying the presented results are an analysis of the compiled statistical indicators used in Romanian forestry and the outcome of a sociological survey conducted on a sample of 345 forest district managers. In early 2013, over 4.4 million hectares of state, public and private forest land were administered by state and experimental forest districts, and over 1.7 million hectares of forest land, other than state-owned, by private forest districts. Note that approximately 0.36 million hectares (over 5% of Romania’s forest area) are not in the care of specialized units, contrary to the legal provisions. The most frequent problems faced by forest district managers arise in relation to the owners of forests or are caused by illegal logging. This study is a contribution to making the concrete problems faced by foresters and especially the structure and ownership related characteristics of forestland the driving force of legislative changes in the forestry sector.