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Farmland birds are reported to decrease strongly in numbers throughout Europe over the last 30 years. Agricultural land abandonment is considered amongst the main drivers for the negative population trends. This process has been studied widely in Western Europe but the evidence for Central and Eastern Europe is limited. We examined the differences in the bird community structure among several secondary succession stages after land abandonment (since the 1940s) in central Bulgaria. Our results demonstrated that avian species richness and diversity decreased with the secondary succession, while no significant difference in the overall bird abundance was observed. The shifts in bird community pattern were mainly related to grassland specialists, which decreased in species richness, diversity and abundance along the succession gradient. Birds of European Conservation Concern were also negatively affected by the woody vegetation overgrowth. We think that in order to stop and reverse the loss of farmland bird diversity in the low-productive mountainous regions of Bulgaria, the rural sustainable development should be reinforced by implementation of agri-environmental and other policy measures that encourage effectively smallscale extensive farming.
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223
ACTA ZOOLOGICA BULGARICA
Acta zool. bulg., 67 (2), 2015: 223-234
*Corresponding author
Terrestrial Ecology and Behaviour
Research Article
Introduction
Over the last 30 years, most of the farmland birds
have declined in Europe (PECBMS 2013). Land
abandonment and agricultural intensication are
considered the main drivers for the negative trends
in the farmland bird populations (He n l e et al. 2008,
St o a t e et al. 2009, Bu t l e r et al. 2010). While ag-
ricultural intensication is considered a more seri-
ous problem in Western Europe (Do n a l D et al. 2001,
2006, Be n t o n et al. 2002, Bá l D i , Ba t á r y 2011a),
land abandonment is of main concern in Central
and Eastern Europe (re i f et al. 2008, ni k o l o v
2010, Sa n D e r S o n et al. 2013, Ra d o v i ć et al. 2013,
Za k k a k et al. 2014). After the fall of the communist
regimes in 1990, most of the countries in the region
passed through a period of major market reforms.
In Bulgaria, this process caused economic and ag-
ricultural crisis, which in turn led to high levels of
depopulation and agricultural land abandonment in
the regions, where agriculture was the main occu-
pation. Both livestock breeding and crop production
were affected, especially in the mountain regions,
where the abandonment process locally began even
earlier (in the 1970s). This affected farmland bird
populations, which were reported to decline, even
Farmland Birds and Agricultural Land Abandonment:
Evidences from Bulgaria
Sylvia Dyulgerova1, Mladen Gramatikov2, Hristo Pedashenko1, Kiril Vassilev1, Vassiliki Kati3,
Stoyan C. Nikolov4*
1 Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113 Soa, Bulgaria
2 GeoMarine Centre Ltd., 45 Solun Street, Soa 1680, Bulgaria
3 Department of Environmental and Natural Resources Management, University of Patras, Seferi 2, 30100 Agrinio, Greece
4Bulgarian Society for Protection of Birds / BirdLife Bulgaria, Yavorov Complex, Bl. 71, Ent. 4, P.O. Box 50, 1111 Soa,
Bulgaria; E-mail: stoyan.nikolov@bspb.org
Abstract: Farmland birds are reported to decrease strongly in numbers throughout Europe over the last 30 years.
Agricultural land abandonment is considered amongst the main drivers for the negative population trends.
This process has been studied widely in Western Europe but the evidence for Central and Eastern Europe
is limited. We examined the differences in the bird community structure among several secondary suc-
cession stages after land abandonment (since the 1940s) in central Bulgaria. Our results demonstrated
that avian species richness and diversity decreased with the secondary succession, while no signicant
difference in the overall bird abundance was observed. The shifts in bird community pattern were mainly
related to grassland specialists, which decreased in species richness, diversity and abundance along the
succession gradient. Birds of European Conservation Concern were also negatively affected by the woody
vegetation overgrowth. We think that in order to stop and reverse the loss of farmland bird diversity in the
low-productive mountainous regions of Bulgaria, the rural sustainable development should be reinforced
by implementation of agri-environmental and other policy measures that encourage effectively small-
scale extensive farming.
Keywords: Agricultural management, common agricultural policy, farmland biodiversity, secondary succession
224
Dyulgerova S., M. Gramatikov, H. Pedashenko, K. Vassilev, V. Kati, S. C. Nikolov
when some of the Eastern European countries joined
the European Union (EU) and implemented agricul-
tural eco-friendly reforms (re i f et al. 2008, Bá l D i ,
Ba t á r y 2011b, Sa n D e r S o n et al. 2013).
Land abandonment fosters secondary succes-
sion and allows regeneration of the native shrubland
and woodland vegetation, which results in loss and
fragmentation of the open habitats at the landscape
scale (fa r i n a 1997, Si r a m i et al. 2007, 2008). These
changes in vegetation structure lead to alterations
in the availability of breeding sites and food supply
for birds as well as in predation pressure (fu l l e r ,
Go u G H 1999). The mentioned changes are bene-
cial for shrubland and woodland birds but negative
for grassland specialists (Po n S et al. 2003, ve r H u l S t
et al. 2004, re i f et al. 2013). However, there is evi-
dence that the biogeographic origin of the avifauna
may determine whether land abandonment brings
conservation benets or detriments (Su á r e Z –Se o a n e
et al. 2002). Some studies in Central Europe dem-
onstrated higher bird species richness in abandoned
habitats compared to managed habitats (la i o l o et
al. 2004, ve r H u l S t et al. 2004, re i f et al. 2013). In
Eastern Europe the processes that occur in bird as-
semblages along the secondary succession gradient
can initially lead to an increase in the species rich-
ness, when shrubland and ecotone species are added
to the species composition of open habitats (ni k o l o v
et al. 2011, Za k k a k et al. 2013). The woody vegeta-
tion overgrowth at late-succession stages gradually
leads to long-term loss of avian diversity, particularly
affecting the grassland birds (Za k k a k et al. 2013,
Mi k u l i ć et al. 2014). In the Balkan region, many
farmland birds of conservation concern are associat-
ed with low intensity farming in mountainous or low
productivity areas (ka t i , Se k e r c i o G l u 2006, ni k o l o v
2010, ni k o l o v et al. 2011), which, in the last few
decades, have been prone to land abandonment due
to the economic depression and rural depopulation.
Bulgaria is a good example of the above sce-
nario. Since 1989, land abandonment has been ob-
served all over the country and according to the Rural
Development Programme of the country for 2007-
2013, the low productivity mountainous regions have
been mostly affected. This trend remained even after
the massive subsidization of agriculture due to the ac-
cession of Bulgaria to the EU in 2007 (via the Common
Agricultural Policy, CAP): only 58.4% of the arable
land in Bulgaria (concentrated in three main regions)
is cultivated (aG r o S t a t i S t i c S , 2011). The results from
the Common Bird Monitoring in the country showed
that the common bird index has a negative trend since
2005, with the most severe decline reported for farm-
land birds (Hr i S t o v , Pe t k o v 2013).
To improve knowledge about the effects of land
abandonment on farmland birds in Eastern Europe,
where deciency of evidence was reported (Bá l D i ,
Ba t á r y 2011a), we tested a hypothesis that the ag-
ricultural land abandonment in Bulgaria leads to
reduction of avian diversity. We also examined the
differences in bird community structure (species
richness, abundance and Shannon diversity) and
composition among gradient secondary successional
stages over a period of 50 years.
Material and Methods
Study area and sampling plots
The study area is part of the Fore-Balkan region
in Central Bulgaria (Fig. 1), where rural depopula-
tion and resulting land abandonment are widespread
(aG r o S t a t i S t i c S 2011). It is located in the Balkan
mixed forest ecoregion of the temperate deciduous
forest vegetation zone (ol S o n et al. 2001) and rang-
es within an altitude of up to 1000 m.
We used sampling plots of 1 x 1 km squares,
based on the European Environmental Agency
(EEA) grid (http://www.eea.europa.eu/data-and-
maps/data/ee a-reference- grids-2#tab-gis-dat a).
The sampling plots, which corresponded to the fol-
lowing criteria, were considered suitable for the
study (Zakkak et al. 2013): (i) 100% covered by
agricultural land used in the 1940s; (ii) currently
with less than 30% of urban area and/or water
bodies (to avoid potential bias due to bird species
tied to settlements or wetlands); (iii) the distance
between centres of two adjacent sampling plots
is more than 4 km (to avoid bird data spatial au-
tocorrelation). We compared the land cover from
orthophoto imagery from 2011 with the land cover
from aerial photographs of the same region from
the past (1945-1946). A total of 64 sampling plots
were found to meet the criteria. Out of those, we
randomly selected 18 sampling plots (Fig. 1) dis-
tributed equally in three vegetation structure (VS)
categories according to the degree of woody vege-
tation (both shrubs and forest) overgrowth, indicat-
ing succession rate (Sirami et al. 2007, vallecillo
et al. 2008, Zakkak et al. 2013): VS1: < 60%; VS2:
60-90%; VS3: >90%. There was no signicant dif-
ferences in the mean altitude among the studied
vegetation structure categories (Kruskal-Wallis
ANOVA, H2,15 = 0.42, p = 0.81).
Land cover mapping and interpretation
We used data from the orthophoto imagery
from 2011 (Ministry of Regional Development da-
Farmland Birds and Agricultural Land Abandonment: Evidences from Bulgaria
225
tabase unpublished), with a grain size of 1 m as
the spatio-thematic source for land cover mapping
and interpretation. Only aerial features limited to a
minimal mapping unit of 100 m² were digitalised as
discrete landscape elements and the maximum width
of linear elements, such as hedgerows, was set to 15
m. By applying a standard scale level of 1:1500 we
could clearly identify and delineate landscape ele-
ments from the image data, which we classied by
22 land cover types (i.e. habitats), displaying the
current state of land use, respectively, agricultural
abandonment (Appendix 1).
The habitat type cover changed signicantly
along the land abandonment gradient, with arable
land, grasslands (pastures and meadows), articial
land and orchards signicantly decreasing (down to
0%), while shrubland and woodland signicantly
increasing (up to 100%) across the vegetation suc-
cession classes. The orchards, which did not present
a signicant differentiation along the gradient, and
the wetlands and bare ground, which were present
in less than ve plots (overall cover < 5%), were not
considered in the analysis (Fig. 2).
Bird sampling
Birds were recorded using the point count meth-
od (Gi B B o n S , Gr e G o r y 2006). Initially, nine point
count stations (PCS) were located systematically
in each sampling plot, placed 300 m apart to avoid
double counting of birds. The following PCS were
excluded from the study: the PCS located closer than
150 meters from rivers, busy roads or settlements;
those that are inaccessible due to physical factors of
relief, fences or others; and those, in which activities
disturbing birds (such as logging, hunting or agricul-
tural activities) were present during the bird counts.
As a result, each sampling plot contained at least six
PCS suitable for the study and the total number of
PCS considered in the analysis was143 for 2011 and
145 for 2012.
The PCS were visited during the greatest bird
activity period: in the morning (05:00 – 11:00 a.m.),
during the height of breeding season (June) in 2011
and in 2012. At each PCS, birds were counted within
a radius of 100 m, based on visual and acoustic reg-
istrations of individuals during two consecutive 5
min sessions (ra l f et al. 1995, Bo n t H o u x , Ba l e n t
2012).
Data analyses
We examined the bird communities using the
following parameters (kr e B S 1999): (i) Species
richness calculated from the means of maximum
number of species recorded in all PCS in each sam-
Fig. 1. Distribution of the sampling plots (N = 18) in the studied area
226
Dyulgerova S., M. Gramatikov, H. Pedashenko, K. Vassilev, V. Kati, S. C. Nikolov
pling plot; (ii) Abundance – calculated from the
means of maximum number of individuals counted in
all PCS in each sampling plot; (iii) Shannon-Wiener
diversity index. For the species richness, data from
10-min count periods were used to avoid overlook-
ing of cryptic and rare species, while for the index
of abundance and Shannon-Wiener diversity index,
data from 5-min intervals were used to avoid double
counting of the same individuals (Gi B B o n S , Gr e G o r y
2006). Raptors, aerial feeders (swallows, swifts and
bee-eaters) and nocturnal species (e.g. Corncrake
Crex crex) were excluded from the analysis because
the point-count method is not appropriate to assess
their abundance (Si r a m i et al. 2007). Moreover,
records of y-overs, as well as data collected in bad
weather conditions (visibility < 200 m; rain; wind >
2 Beaufort) were not considered in the analysis. As
there were no signicant differences of studied bird
community parameters between years (Wilcoxon
Matched Pairs Test: T = 62.5, p = 0.32 and T = 63.0,
p = 0.33, respectively for the species richness and
abundance), data were pooled for the analyses.
Birds were classied in functional groups ac-
cording to their main habitat: grassland, shrubland,
woodland or other type of habitat (ia n k o v 2007),
as well as species from the European Conservation
Concern (SPEC) list (Bi r D li f e in t e r n a t i o n a l 2004;
see Appendix 2). Separately, we analysed the bird-
habitat associations of all the species (n = 21) re-
corded in both years of the study, in more than ve
sampling plots per year and with total abundance of
20 or more individuals.
Because data were not normally distributed
and did not approach the normal distribution even
after transformation, non-parametric tests (Kruskal-
Wallis ANOVA and Spearman-Rank Correlation test)
were used. The statistical analysis was conducted
by STATISTICA 7.0 (St a t So f t 2004). The ordina-
tion analysis was applied using CANOCO 4.5 (t e r -
Br a a k , Sm i l a u e r 2002). The length of gradient in a
dataset was checked by Detrended Correspondence
Analysis (DCA). The bird associations along the
studied landscape gradients were determined by
Canonical Correspondence Analysis (CCA). The
signicance of canonical axes was assessed by the
Monte Carlo Permutation test.
Results
Bird community structure along the secondary
succession gradient
We recorded 61 bird species (3587 individuals), of
which an important proportion of 30% was SPEC
(Appendix 2). The dominant group was woodland
Fig. 2. Habitat cover across the three vegetation succession classes (VS1 : <60%, VS2: 60-90%, VS3: >90% of woody
vegetation cover)
Farmland Birds and Agricultural Land Abandonment: Evidences from Bulgaria
227
birds (66%), including a small proportion of SPEC
species (23%). Grassland birds accounted for a small
proportion of species richness (11%), but included
the largest proportion of SPEC species (56%).
Shrubland (16%) and other birds (7%) included also
quite an important number of SPEC species (30%
and 50%, respectively).
Bird species richness and Shannon-Wiener di-
versity index signicantly decreased along the veg-
etation succession gradient (VS1 to VS3), when all
bird species were considered; however, the overall
abundance did not differ signicantly among the
vegetation succession classes (Table 1). The diversi-
ty of grassland and SPEC species (species richness,
Shannon-Wiener diversity index, and abundance)
also signicantly and strongly decreased along the
vegetation succession gradient. There were no sig-
nicant differences in the shrubland and woodland
bird diversity among the three vegetation succession
classes (Table 1).
Bird-habitat associations
The main gradients in the landscape, which in-
uenced the bird species composition, were related to
secondary succession (transition from semi-natural
grasslands and arable lands to woody vegetation) and
the structure of farmlands (from arable lands to rural
mosaics; Fig. 3). Accordingly, there were two main
bird assemblages: (i) related to open landscapes (ara-
ble lands and semi-natural grasslands) and (ii) woody
vegetation and rural mosaics. The early-successional
stages were dominated by grassland (Corn Bunting
Emberiza calandra and Skylark Alauda arvensis) and
shrubland specialists (Blackbird Turdus merula, Red-
backed Shrike Lanius collurio, Common Whitethroat
Sylvia communis; Fig. 4a,b), while the latest suc-
cessional stage was dominated by woodland birds
(Common Chafnch Fringilla coelebes, Common
Chiffchaff Phylloscopus collybita, Great tit Parus ma-
jor, Robin Erithacus rubecula, etc.; Fig.4c).
Discussion
Shifts in bird community structure
Our results demonstrated that the overall species rich-
ness and Shannon-Wiener diversity index decreased
along the succession gradient, while the overall bird
abundance remained stable. Similar results were re-
ported for the extensively grazed and abandoned up-
land pastures in Western Bulgaria (ni k o l o v 2010).
These results could be explained with the similarity
in the ecological capacity of the natural habitats to
host as much avian diversity as farmland environ-
ment (na v a r r o , Pe r e i r a 2012, Gu i l H e r m e , mi G u e l
Pe r e i r a 2013). Previous works (e.g. Sa n t o S 2000,
la i o l o et al. 2004, Si r a m i et al. 2008, ni k o l o v et al.,
2011, Za k k a k et al. 2013) reported an increase in spe-
cies richness and diversity in the successional stages
just after abandonment due to an inux of shrubland
and ecotone species to the community, while open
habitat species still persist there. A gradual decrease
in the species richness and Shannon-Wiener diver-
sity index with vegetation succession in this study
could be explained by the fact, that the study did not
include the intensively managed farmland as start-
ing point of the succession. Such intensive agricul-
tural land use (on one extreme end of the gradient) is
considered the main driver of the widespread farm-
land bird declines observed in Europe (Do n a l D et al.
2001, 2006). At the same time, the late-successional
habitats as scrubland and woodland (on the other
extremity of the gradient) were reported to support
high avian species richness in Central and Western
Europe (Gu i l H e r m e , mi G u e l Pe r e i r a 2013, re i f et
al. 2013).
We found that the diversity of grassland birds
and SPEC birds was affected negatively by the post-
abandonment vegetation succession. This result sup-
ports the view that the secondary succession through
the agricultural land abandonment is the reason for
the grassland bird diversity loss, as it is already
Table 1.Differences in bird community structure among three-scale vegetation succession gradient (VS1 : <60%, VS2:
60-90%, VS3: >90% of woody vegetation cover), based on Kruskal-Wallis ANOVA test (K-W), and relation between
studied bird community parameters and woody vegetation cover, based on Spearman correlation coefcient (rho).*:
p<0.05, **:p<0.01, ***:p<0.001, ns: p>0.05.
Bird group Species richness Shannon index Abundance
K-W rho K-W rho K-W rho
All species 6.25* - 0.36* 13.34** - 0.54* 5.71 ns -
SPEC species 18.77*** - 0.77* 16.74*** -0.75* 16.74*** -0.73*
Grassland birds 20.87*** - 0.81* 9.98** - 0.59* 17.87*** - 0.77*
Shrubland birds 3.36 ns - 4.27 ns - 0.36 ns -
Woodland birds 3.38 ns - 1.96 ns - 0.83 ns -
228
Dyulgerova S., M. Gramatikov, H. Pedashenko, K. Vassilev, V. Kati, S. C. Nikolov
known for the Mediterranean region (Pr e i S S et al.
1997, fa r i n a 1997, Sa n t o S 2000) and recently de-
scribed for the Balkans (ni k o l o v 2010, Za k k a k et
al. 2013, Mi k u l i ć et al. 2014). Actually, the early-
successional stages in the present study, with which
these groups of birds were associated, were similar
to the heterogeneous agricultural landscape under
traditional extensive farming, known to be benecial
for farmland biodiversity (ka t i , Se k e r c i o G l u 2006,
ka t i et al. 2009, ni k o l o v et al. 2011).
Effects of secondary succession at species level
The common bird species composition along
the succession gradient showed the expected initial
prevailing of open habitat species (e.g. Corn Bunting,
Red-backed Shrike and Skylark), displaced at late-
successional stages by shrubland (e.g. Blackbird
and Common Whitethroat) and ecotone species
(e.g. Common Chiffchaff and Robin), and nally,
predominated by woodland species (e.g. Common
Chafnch, Great Tit and Song Thrush).
Species respond in an idiosyncratic way to the
habitat types analysed, given their different degree of
specialisation (fu l l e r et al. 2004). Some open habi-
tat species (e.g. Skylark, Corn and Ortolan Buntings)
respond negatively to land abandonment due to
habitat loss through the turnover in late-successional
stages (va l l e c i l l o et al. 2008), and negative for-
est edge effects (fo n D e r f l i c k et al. 2013). Others
(e.g. Woodlark, Red-backed Shrike and Common
Whitethroat) are more tolerant to secondary suc-
cession due to ‘complementation’ type response,
being favored by the coexistence of both farmland
and shrubland landscapes (ka t i , Se k e r c i o G l u 2006,
tS i a k i r i S et al. 2009, Za k k a k et al. 2013) and should
be expected to persist longer in the changing habitat.
In the present study, most of the predominant
species at late-successional stages (e.g. Blackbird,
Common Chafnch, Great Tit, and Robin) were
generalists (ka t i , Se k e r c i o G l u 2006, ia n k o v 2007),
while relatively more SPEC species were tied to
early-successional stages and responded negatively
to agricultural land abandonment. The results are in
agreement with the work of re i f et al. (2013) and
Za k k a k et al. (2013), showing that early-successional
stages host bird communities with the highest habitat
specialisation and threat level (but see Ra d o v i ć et al.
2013, Mi k u l i ć et al. 2014). Therefore, the popula-
tion declines of the common bird species in Bulgaria
(Hr i S t o v , Pe t k o v 2013) tied to open habitats (arable
lands and grasslands) and found to respond nega-
tively to secondary succession (e.g. Skylark, Red-
backed Shrike, Ortolan and Corn Buntings), should
be further investigated in relation to the nationwide
abandonment of arable lands in the low-productivity
mountainous regions, besides the other operating
factors.
Conservation implications
Conservation implications for biodiversity vary
since the arable land abandonment results from mul-
tiple drivers and is not per se a positive or negative
process (Be i l i n et al. 2014). Extensive grazing in the
former hilly and mountainous cultivations has been
proposed by some authors (ni k o l o v 2010, ni k o l o v
et al. 2011, Za k k a k et al. 2013) as an alternative
solution to maintain open landscape structure and
open-land farmland birds. Under appropriate zona-
tion regime, this type of management has been sug-
gested as an efcient measure also for sustaining
vegetation diversity in open-grassland and mid-suc-
cessional grassland communities in the Balkan up-
lands (va S S i l e v et al. 2012). Nevertheless, grazing is
not an adequate solution in all cases, as many of the
farmland bird species are tied to arable land rather
Fig. 3. CCA biplot graph of bird species and main habi-
tat types. Canonical axes were statistically signicant
(Monte Carlo permutation test, F = 1.48, p = 0.03) and the
model explained 89.6% of data variability. Bird species
are indicated as triangles (see Appendix 2 for acronyms).
Habitat variables are indicated as arrows: Woody – forests
and shrubs; Arable – arable lands; HedgeORrural mo-
saics (hedges and orchards); Urban – roads and articial
structures; Grassland – meadows and pastures
Farmland Birds and Agricultural Land Abandonment: Evidences from Bulgaria
229
than to pastures only (ni k o l o v et al. 2011, Za k k a k
et al. 2013). Shrub-clearing (Bo c c a c c i o et al. 2009)
and logging in former agricultural land (Za k k a k
et al. 2013) have been also promoted to maintain
open spaces in the Balkan context. Based on the as-
sumption that bird communities can adapt to land-
use changes derived from farmland abandonment,
Gu i l H e r m e , mi G u e l Pe r e i r a (2013) argued that rewil-
ding may be a suitable management option for many
European mountain areas. Indeed, at metapopulation
level, an animal species can temporarily persist (i.e.
can have a low local extinction rate) even after se-
vere habitat fragmentation or after a sharp decrease
in habitat quality (Si r a m i et al. 2008). However,
the results from the present study clearly indicated
a decrease in the species richness, abundance and
diversity of grassland birds, while a simultaneous
opposite trend in the shrubland and woodland birds
was not observed. Therefore, at least for the studied
region, rewilding cannot be considered an appropri-
ate compensation method for the farmland bird di-
versity loss. Most of the conservation implications
Fig. 4. Dominant structure of bird communities in the studied successional stages (a) VS1: <60%, (b) VS2: 60-90%,
and (c) VS3: >90% of woody vegetation cover (see Appendix 2 for bird species acronyms)
230
Dyulgerova S., M. Gramatikov, H. Pedashenko, K. Vassilev, V. Kati, S. C. Nikolov
for reversing the negative effects of agricultural land
abandonment on birds are related to maintenance of
extensive traditional farming and livestock rearing
within rural mosaics (ka t i et al. 2009, ni k o l o v et
al. 2011, Za k k a k et al. 2013, He r Z o n et al. 2014),
which fully corresponds to the agricultural manage-
ment and habitat conguration of the studied area
in the past (unpublished data from questionnaires of
old people and aerial photographs from 1945-1946,
collected during the present study).
Land abandonment is more strongly inuenced
by socio-economic factors, such as farming subsi-
dies and land reforms, than the characteristics of
the land itself (al c a n t a r a et al. 2013). Therefore,
the low productive mountainous regions in Bulgaria
need appropriate management, not only for the ben-
et of biological diversity, but also for the sake of
quality of life of the rural communities. The latter
is particularly important, as the rural poverty and
low standard of living tied to small scale extensive
farming cannot be promoted only on the grounds of
their association with high nature conservation-val-
ue farmland (mccr a c k e n et al. 1997). An integrated
approach to agricultural, environmental and social
policies for such areas is, therefore, highly recom-
mended (la i o l o et al. 2004). Similarly to the results
from Greece (Za k k a k et al. 2013) and from Croatia
(Mi k u l i ć et al. 2014), this study suggests that these
policies could be developed and implemented at
the Balkan rather than national level, at least for
the EU member states or candidate member states.
They may include promotion of extensive farming,
establishment of an adequate market system for lo-
cal products, and subsidies for both extensive culti-
vation and grazing in order to enhance the income
of agricultural activities in remote mountain areas
(Za k k a k et al. 2013).
Acknowledgements: This study was conducted under the
AGRALE project (Sub-project ERA 164/04) funded by SEE-
ERA.NET PLUS scheme. We would like to thank Thomas Wrb-
ka, Andreja Radović, Spase Shumka, Michael Kuttner, Stefan
Schindler, and Mirjan Topi, for their expertise and fruitful dis-
cussions, as well as Dimitar Zarev and Vladimir Petrov for their
assistance in bird data collection. Irina Herzon, Riho Marja and
Pavel Zehtindzhiev provided valuable comments on an earlier
draft of the manuscript. Penka Tzekova proofread the paper and
improved the English.
References
aG r o S t a t i S t i c S 2011. BANAEC: Final results on the oc-
cupancy and land use for the territory of Bulgaria in
2011. – Bulletin of the Ministry of agriculture and
food, 182: 1-20. (in Bulgarian)
Bá l D i a., P. Batáry 2011a. Spatial heterogeneity and
farmland birds: different perspectives in Western and
Eastern Europe. – Ibis, 153: 875–876.
Bá l D i a., P. Ba t á r y 2011b. The past and future of farmland
birds in Hungary. – Bird Study, 58: 365-377.
Be i l i n r, r. li n D B o r G , m. St e n S e k e , H. mi G u e l Pe r e i r a , a.
ll a u S a S f , e. Sl a t m o , y. ce r q u e i r a , l. na v a r r o , P.
ro D r i G u e S , n. re i c H e l t , n. mu n r o , and c. qu e i r o Z
2014. Analysing how drivers of agricultural land
abandonment affect biodiversity and cultural land-
scapes using case studies from Scandinavia, Iberia
and Oceania. – Land Use Policy, 36: 60-72.
Be n t o n T. G., D. M. Br y a n t , l. co l e and H. Q. P. cr i c k
2002. Linking agricultural practice to insect and bird
populations: a historical study over three decades. –
Journal of Applied Ecology, 39: 673-687.
Bi r D li f e in t e r n a t i o n a l 2004. Birds in Europe: population
estimates, trends and conservation status. BirdLife
International Conservation Series No. 12. Cambridge,
UK (BirdLife International). 374 p.
Bo c c a c c i o l., J. He G a r t y and a. Br u n n e r 2009.Through
the green smokescreen. How is CAP cross compli-
ance delivering for biodiversity? UK (BirdLife
International). 44 p.
BontHoux S., G. Balent 2012. Point count duration:
five minutes are usually sufficient to model the
distribution of bird species and to study structure of
communities for a French landscape. – Journal of
Ornithology, 153: 491-504.
Bu t l e r S. J., l. Bo c c a c c i o , r. D. Gr e G o r y , P. vo r i S e k ,
and k. norriS 2010. Quantifying the impact of
land-use change to European farmland bird popula-
tions. Agriculture, Ecosystems and Environment,
137: 348-357.
Do n a l D P. f., r. e. Gr e e n and M. F. He a t H 2001. Agri-
cultural intensication and the collapse of Europe’s
farmland bird populations. Proceedings of the.
Royal Society B, 268 (1462): 25-29.
Do n a l D P. f., f. J. Sa n D e r S o n , i. J. Bu r f i e l D and F. P. J.va n
Bo m m e l 2006. Further evidence of continent-wide
impacts of agricultural intensication of European
farmland birds, 1990–2000. – Agriculture, Ecosys-
tems and Environment, 116: 189-196.
farina, a 1997. Landscape structure and breeding bird
distribution in a sub-Mediterranean agro-ecosystem.
Landscape Ecology, 12: 365-378.
fo n D e r f l i c k J., a. Be S n a r D and J. l. ma r t i n 2013. Species
traits and the response of open-habitat species to for-
est edge in landscape mosaics. – Oikos, 122: 42-51.
fu l l e r r. J., S. J. Go u G H 1999.Changes in sheep numbers in
Britain: implicationsfor bird populations. Biological
Conservation, 91: 73-89.
Farmland Birds and Agricultural Land Abandonment: Evidences from Bulgaria
231
fu l l e r r. J., S. a. Hi n S l e y and r. D. Sw e t n a m 2004. The
relevance of non-farmland habitats, uncropped areas
and habitat diversity to the conservation of farmland
birds. –Ibis, 146 (2): 22-31.
Gi B B o n S D. W., R. D. Gr e G o r y 2006. Point counts or point
transects. In: Su t H e r l a n D W. J. (Ed.): Ecological
census techniques. UK (Cambridge Univ. Press),
324-332.
Gu i l H e r m e J. l., H. mi G u e l Pe r e i r a 2013. Adaptation of
Bird Communities to Farmland Abandonment in
a Mountain Landscape. PLoS ONE 8(9): e73619.
doi:10.1371/journal.pone.0073619
He n l e k., D. al a r D , J. cl i t H e r o w , P. co B B , l. fi r B a n k , t.
ku f f , D. mccr a c k e n , r. f. a. mo r i t Z , J. ni e m e l ä ,
m. re B a n e , D. wa S c H e r , a. wa t t and J. yo u n G 2008.
Identifying andmanaging the conictsbetween agri-
culture and biodiversity conservation in Europe – A
review. – Agriculture, Ecosystems and Environment,
124: 60-71.
He R z o n i., a. au n i n љ , J. el t s , and Z . Pr i e k S a 2006. Habitat
associations of farmland birdsacross the East Baltic
region. – Acta Zoologica Lituanica., 16: 249-260.
He r Z o n , i., r. ma r J a , S. me n S H i k o v a and a. ko n D r a t y e v
2014. Farmland bird communities in an agricultural
landscape in Northwest Russia: seasonal and spatial
patterns. Agriculture, Ecosystems and Environment,
183: 78-85.
HriStov i., n. Petkov 2013. State of Common Birds
in Bulgaria 2005-2011. Bulgarian Society for the
Protection of Birds Conservation series, Book 26.
Soa, Bulgaria (Bulgarian Society for the Protection
of Birds). 25 p.
ia n k o v P. (Ed.) 2007. Atlas of breeding birds inBulgaria.
Soa, Bulgaria (Bulgarian Society for the Protection
of Birds). 679 p.
kati v., c. H. SekercioGlu 2006. Diversity, ecological
structure, and conservation of the land bird com-
munity of Dadia reserve, Greece. Diversity and
Distributions, 12: 620-629.
ka t i v., P. Di m o P o u l o S , H. Pa P a i o a n n o u and k. Po i r a Z i D i S
2009. Ecological management of a Mediterranean
mountainous reserve (Pindos National Park, Greece)
using the bird community as an indicator. – Journal
for NatureConservation, 17 (1): 47-59.
kr e B S c. 1999. Ecological methodology. 2nd Edn. Men-
loPark, California (Benjamin/Cummings). 624 p.
la i o l o P., f. Do n D e r o , e. ci l i e n t o , and a. ro l a n D o 2004.
Consequences of pastoral abandonment for the struc-
ture and diversity of the alpine avifauna. – Journal
of Applied Ecology, 41: 294-304.
ma c DonalD D., J. r. craBtree, G. wieSinGer, t. Da x ,
n. St a m o u , P. fl e u r y , J. G. la Z P i t a and a. Gi B o n
2000. Agricultural abandonment in mountain areas of
Europe: envi-ronmental consequences and policyre-
sponse. Journal of Environmental Management,
59: 47-69.
mccr a c k e n D. i., m. Pi e n k o w S k i , e. Bi G n a l , D. Ba l D o c k ,
c. tu B B S , n. ye l l a c H i c H , H. co r r i e and G. v a n Di J k
1997. The importance of livestock farming for nature
conservation. Mountain Livestock Farming and EU
Policy Development. – In: Po o l e a., m. Pi e n k o w S k i ,
D. i. mccracken, f. Petretti, c. Br é D y and c.
De f f e y e S (Eds.): Proceedings of the Fifth European
Forum on Nature Conservation and Pastoralism
(Cogne, Italy), 19-28.
Mi k u l i ć k., a. Ra d o v i ć , v. ka t i , s. d. Je l a n s k a and n.
tepić 2014. Effects of land abandonment on bird
communities of small holder farming landscapes in
post-war Croatia: implications for conservation poli-
cies. – Community Ecology, in press.
na v a r r o l. m., H. m. Pe r e i r a 2012. Rewilding abandoned
landscapes in Europe. – Ecosystems, 15: 900-912.
nikolov S. C. 2010. Effects of land abandonment and
changing habitat structure on avian assemblages in
upland pastures of Bulgaria. Bird Conservation
International, 20: 200-213.
ni k o l o v S. c., D. a. De m e r D Z H i e v, G. S. Po P G e o r G i e v and
D.G. Pl a c H i y S k i 2011. Bird community patterns in
sub-Mediterranean pastures: the effect of shrub cover
and grazing intensity. – Animal Biodiversity and
Conservation, 34: 11-21.
ol S o n D.m., e. Di n e r S t e i n , e. D. wi k r a m a n a y a k e , n. D.
Bu r G e S S , G. v. n. Po w e l l , e. c. un D e r w o o D , J. a.
D’am i c o , i. it o u a , H. e. St r a n D , J. c. mo r r i S o n , c.
J. lo u c k S , t. f. al l n u t t , t. H. ri c k e t t S , y. ku r a ,
J. f. lamoreux, w. w. wettenGel, P. HeDao and
k. r. ka S S e m 2001. Terrestrial ecoregions of the
world: New map of life on earth. –Bioscience, 51
(11):933-938.
PECBMS 2013. Population Trends of Common European
Breeding Birds 2013. Prague (PECBMS, CSO).
Available at: http://www.ebcc.info/wpimages/video/
Leaet2013.pdf
PonS P., B. lamBert, e. riGolot and r. ProDon 2003.
The effects of grassland management using re on
habitat occupancy and conservation of birds in a
mosaic landscape. – Biodiversity and Conservation,
12: 1843-1860.
PreiSS e., J. l. martin and m. DeBuSScHe 1997. Rural
depopulation and recent landscape changes in a
Mediterranean region: consequences to the breeding
avifauna. – Landscape Ecology, 12: 51-61.
Ra d o v i ć a., s. C. ni k o l o v , n. te p i ć , k. Mi k u l i ć , s. d.
Je l a S k a and i. Bu D i n S k i 2013. The inuence of land
abandonment on farmland bird communities: a case
study from a oodplain landscape in Continental
Croatia. – Folia Zoologica, 62 (4): 269-281.
ra l P H c. J., S. Dr o e G e and J. R. Sa u e r 1995.Managing and
Monitoring Birds Using Point Counts: Standards and
Applications. – In: ra l P H c. J., J. R. Sa u e r and S.
Dr o e G e (Eds.): Monitoring BirdPopulations by Point
Counts (Albany, CA), 161-169.
232
Dyulgerova S., M. Gramatikov, H. Pedashenko, K. Vassilev, V. Kati, S. C. Nikolov
re i f J., P. ma r H o u l and J. ko P t í k 2013. Bird communities
in habitats along a successional gradient: Divergent
patterns of species richness, specialization and threat.
– Basic and Applied Ecology, 14: 423-431.
Re i f J., p. vo ř í š e k , k. šť a s t n ý , v. Be J č e k and J. Pe t r 2008.
Agricultural intensication and farmland birds: new
insight from a central European country. – Ibis, 150:
596-605.
Sa n D e r S o n f. J., m. ku c H a r Z , m. Jo B D a and P. f. Do n a l D
2013. Impacts of agricultural intensication and
abandonment on farmland birds in Poland follow-
ing EU accession. Agriculture, Ecosystems and
Environment, 168: 16-24.
Sa n t o S C. 2000. Succession of breeding bird communities
after the abandonment of agricultural elds in south-
east. Portugal. – Ardeola, 47 (2): 171-181.
Si r a m i c., l. Br o t o n S and J. l. ma r t i n 2007. Vegetation
and songbird response to land abandonment: from
landscape to census plot. – Diversity and Distribu-
tions, 13: 42-52.
Si r a m i c., l. Br o t o n S , i. Bu r f i e l D , J. fo n D e r f l i c k and J. l.
ma r t i n 2008. Is land abandonment having an impact
on biodiversity? A meta-analytical approach to bird
distribution changes in the north-western Mediter-
ranean. – Biological Conservation, 141: 450-459.
St a t So f t 2004. STATISTICA 7.0. Data analysis software.
Tulsa, USA (StatSoft Inc). Available at: http://www.
statsoft.com/
St o a t e c., a. Bá l D i , P. Be J a , n. D. Bo a t m a n , i. He r Z o n , a.
va n Do o r n , G. r. D e Sn o o , l. ra k o S y and c. ra m -
w e l l 2009. Ecological impacts of early 21st century
agricultural change in Europe- a review. Journal of
Environmental Management, 91: 22-46.
SuáreZ–Seoane S., P. e. oSBorne and J. BauDry 2002.
Responses of birds of different biogeographic origins
and habitat requirements to agricultural land aban-
donment in northern Spain. – Biological Conserva-
tion, 105: 333-344.
t e r Br a a k c. J. f., P. Sm i l a u e r 2002. Canoco for Windows,
Version 4.5. Wageningen (Biometris Plant Research
International).
tSi a k i r i S r., k. St a r a , J. Pa n t i S and S. SG a r D e l i S 2009.
Microhabitat selection by three common bird species
of montane farmlands in northern Greece. Environ-
mental Management, 44: 874-887.
vallecillo S., L. Br o t o n S and S. He r r a n D o 2008. As-
sessing the response of open-habitat bird species to
landscape changes in Mediterranean mosaics. Bio-
diversity and Conservation, 17: 103-119.
va S S i l e v k., H. Pe D a S H e n k o , S. c. ni k o l o v , i. aP o S t o l o v a
and J. De n G l e r 2011. Effect of land abandonment on
the vegetation of upland semi-natural grasslands in
the Western Stara Planina, Bulgaria. – Plant Biosys-
tems, 145 (3): 654-665.
ve l e v S. 2002. Climatic zoning. – In: ko P r a l e v I. (Ed.):
Geography of Bulgaria. Physical and socio-economic
geography. Soa, Bulgaria (ForKom Publisher), 155-
156. (in Bulgarian)
verHulSt J., a.Bá l D i and D. kleiJn 2004. Relationship
between land-use intensity and species richness and
abundance of birds in Hungary. – Agriculture, Eco-
systems and Environment, 104: 465-473.
za k k a k s., e. ka k a l i s , a. Ra d o v i ć , J. M. Ha l l e y and v.
ka t i 2013. The impact of forest encroachment after
agricultural land abandonment on passerine bird com-
munities: The case of Greece. – Journal for Nature
Conservation, in press, http://dx.doi.org/10.1016/j.
jnc.2013.11.001
Received: 19.02.2014
Accepted: 30.10.2014
Appendix 1. Land cover types (i.e. habitats) description
Land Cover Type Description
Arable Land (AL) Grain, forage crops, root crops
Meadow (ME) No bare soil, uniform texture, traces of mowing
Pasture (PA) Obvious signs of pastoral use like trampling
Orchard (OR) Fruit tree plantation
Vineyard (VY) Vineyards
Coarse grassland (CGR) Extensively used grasslands (including fallow lands), showing a coarse texture
Heterogeneous grassland (HGR) Extensively used grasslands (including fallow lands), showing a heterogeneous structure
Shrublands (SHR) Shrubby vegetation (> 75 % shrub cover)
Broad-leaved forest (BLFO) Forest with < 20 % coniferous trees
Coniferous forest (CFO) Forest with < 20 % broad-leaved trees
Mixed forest (MFO) Forest with > 20 % broad-leaved and coniferous trees
Open forest (OFO) 30 - 50 % tree cover
Farmland Birds and Agricultural Land Abandonment: Evidences from Bulgaria
233
Land Cover Type Description
Small woodlot (WL) All forest types < 1,500 m²
Articial surface (AS) Built up areas, incl. settlements, parking spaces, extraction sites, etc.
Bare surface (BAR) Bare rock or soil, eroded areas
Baulk (BA) Field margins, ridges, embankments
Burnt surface (BUR) Burnt areas, especially forests and shrublands
Hedge (HD) Hedgerows of shrubs and/or trees
Road (RO) Sealed, gravel or dirt roads
Sparsely vegetated areas (SVA) < 50 % vegetation cover (all types)
Standing waterbody (WBSN) Lakes, ponds, water reservoirs
Streaming waterbody (WBSR) Rivers, streams, channels
Appendix 2. Bird species, overall abundance, habitat preference, and conservation status.
G: Grassland birds, S: Shrubland birds, W: Woodland birds, O: Other birds (ia n k o v 2007). SPEC 1: Species in Europe
of global conservation concern, SPEC2: Species, whose global population is concentrated in Europe, with unfavour-
able conservation status in Europe, SPEC3: Species, whose population is not concentrated in Europe, with unfavour-
able conservation status in Europe (Bi r D l i f e in t e r n a t i o n a l 2004)
Bird species Code Abundance Habitat Conservation status
Aegithalos caudatus Aegcau 7 W -
Alauda arvensis Alaarv 134 G SPEC 3
Anthus trivialis Anttri 19 W -
Carduelis cannabina Carcan 3 G SPEC 2
Carduelis carduelis Carcar 4 W -
Carduelis chloris Carchl 10 W -
Certhia brachydactyla Cerbra 8 W -
Coccothraustes coccothraustes Coccoc 40 W -
Columba palumbus Colpal 17 W -
Corvus corone Corcor 2 W -
Coturnix coturnix Cotcot 13 G -
Crex crex Crecre 5 G SPEC 1
Cuculus canorus Cuccan 59 W -
Cyanistes caeruleus Cyacae 40 W -
Dendrocopos major Denmaj 28 W -
Dendrocopos minor Denmin 5 W -
Dendrocopos syriacus Densyr 1 W -
Dryocopus martius Drymar 7 W -
Emberiza calandra Embcal 376 G -
Emberiza citrinella Embcit 125 W -
Emberiza hortulana Embhor 115 S -
Emberiza melanocephala Embmel 2 S -
Erithacus rubecula Erirub 173 W -
Ficedula semitorquata Ficsem 1 W SPEC 2
Fringilla coelebs Fricoe 293 W -
Garrulus glandarius Gargla 78 W -
Hippolais pallida Hippal 4 S SPEC 3
Jynx torquilla Jyntor 10 W SPEC 3
Appendix 1. Continued
234
Dyulgerova S., M. Gramatikov, H. Pedashenko, K. Vassilev, V. Kati, S. C. Nikolov
Bird species Code Abundance Habitat Conservation status
Lanius collurio Lancol 209 S SPEC 3
Lanius senator Lansen 1 S SPEC 2
Lullula arborea Lularb 24 G SPEC 2
Luscinia megarhynchos Lusmeg 117 W -
Motacilla ava Mota 9 G -
Muscicapa striata Musstr 3 W SPEC 3
Oriolus oriolus Oriori 28 W -
Parus lugubris Parlug 4 W -
Parus major Parmaj 187 W -
Parus montanus Parmon 3 O -
Passer domesticus Pasdom 42 O SPEC 3
Passer montanus Pasmon 2 O SPEC 3
Phasianus colchicus Phacol 5 O -
Phoenicurus ochruros Phooch 1 S -
Phylloscopus collybita Phycol 283 W -
Phylloscopus sibilatrix Physib 12 W SPEC 2
Phylloscopus trochilus Phytro 5 W -
Picus canus Piccan 3 W SPEC 3
Picus viridis Picvir 18 W SPEC 2
Poecile palustris Poepal 9 W -
Sitta europaea Siteur 30 W -
Streptopelia turtur Strtur 21 W SPEC 3
Sturnus vulgaris Stuvul 18 W SPEC 3
Sylvia atricapilla Sylatr 124 W -
Sylvia borin Sylbor 2 W -
Sylvia communis Sylcom 140 S -
Sylvia curruca Sylcur 3 S -
Sylvia nisoria Sylnis 16 S -
Troglodytes troglodytes Trotro 9 W -
Tudus merula Turmer 498 S -
Turdus philomelos Turphi 158 W -
Turdus viscivorus Turvis 12 W -
Upupa epops Upuepo 12 W SPEC 3
Total 61 3587
Appendix 2. Continued
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... Likewise, Cluster 7, exhibits special interest in the relation between land abandonment and some bird communities in Eastern Europe. Some conclusions indicated that new land use management and conservation policies needed to be developed which focused on land abandonment areas (Mikulić et al., 2014) and rural sustainable development should be supported to encourage effective small scale extensive farming (Dyulgerova et al., 2015). ...
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The scientific production on rural depopulation has grown in recent years. However, a global picture of the research carried out on this topic does not exist. The aim of this study is to identify the worldwide trends in rural depopulation scientific production over time in the main levels of analysis: sources, authors and documents. A bibliometric analysis was developed to analyse a final sample of 1150 articles published between 1979 and 2018. In order to develop the analysis, bibliometrix R-Tool was used and the metadata of two databases (WoS and Scopus) was retrieved and merged. Results show two major areas of co-citation networks; a poor network of collaboration between countries with some highlighted interaction; an author collaboration network with close groups of knowledge and two main themes resulting from a co-word analysis. The main conclusion is that rural depopulation is not yet a solid field of research and the most important themes identified are related to specific geographical areas. However, international collaborations are growing, new trends appearing, and other related fields are expressing greater interest in rural depopulation, which could indicate the preceding stage to an eventual consolidation of the theme. This finding can assist future research in this or related fields by providing a worldwide overview of rural depopulation research over time.
... Woodland species increased in all landscape types, whereas shrubland species increased only in mixed landscapes. In the eastern Mediterranean, forest encroachment following land Mediterranean Forests · 337 abandonment at local scales did not strongly influence bird community structure (Mikulić et al. 2014;Dulgerova et al. 2015), although increases in diversity and abundance of forest-dwelling species have been reported (Zakkak et al. 2014). When examined at a regional cross-national scale, such as in the Balkan Peninsula, agricultural land abandonment has a negative effect on overall bird diversity, but it significantly increases forest bird abundance (Zakkak et al. 2015). ...
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The recession of agriculture in Russia approximately from mid 2000s changed to an increase, accompanied by the reversion to intensive technologies, market transition to cultivation of quick payback crops (potatoes, rapeseed, sunflower) and raising pigs and poultry instead of the cattle; transition from grazing of cattle to indoor keeping system. The rates of this increase are not equal in different economic sectors and regions of European Russia. It is more pronounced in the Black Soil zone and in the south of European Russia as well as in some of regions in the south of Non-Black Soil zone. These changes have been particularly evident during the last decade and resulted in changes of the crop structure and development in some regions new for them directions of agriculture. They are determined both by socio-economic factors and current climate changes. In general, the nowaday trend of agriculture development is that pastures and most hayfields are becoming irrelevant, whereas the demand for arable fields is increasing. Modern agriculture intensification is different from the intensification of the mid 20th century, as large areas are still abandoned and therefore getting more overgrown. As a result the considerable polarization of bird habitats formed in European Russia exhibited splitting into extensive abandoned lands, of low suitability for nesting by typical grassland species, and into increasingly intensively cultivated fields.
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