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Acrocephalus 39 (178/179): 71–83, 2018
10.1515/acro-2018-0006
Black Kite Milvus migrans in Slovenia – its distribution, 
phenology, breeding and habitat
Črni škarnik Milvus migrans v Sloveniji – razširjenost, fenologija, gnezditev in 
habitat
Dejan Bordjan
Oddelek za gozdarstvo in obnovljive gozdne vire, Biotehniška fakulteta, Univerza v Ljubljani, Večna pot 83, SI-1000 
Ljubljana, e-mail: dejan.bordjan@gmail.com 
Between 1984 and 2017, 1,388 Black Kites were recorded, mostly in 
lowlands with 70% of observations made at Dravsko polje. They were 
observed from sea level to around 1,600 m a.s.l. with an average elevation 
of 271  m a.s.l. The species was present in Slovenia from mid-March to 
early December with indistinct spring and autumn migrations. The 
highest number of observations was recorded in May. The Black Kite was 
observed in 71 out of 238 10x10  km grid squares in Slovenia (29.8%), 
with more observations around known breeding sites and at sites with 
higher observer effort. Both the number of observations and the number 
of probable and confirmed breeding pairs increased. In 2011–2018, 
10 breeding pairs were found at 7 sites (3–7 per year). Additionally, 11 
probable breeding pairs at 9 sites (0–6 pairs per year) were found. The 
breeding population in 2011–2018 is estimated at 10–21 pairs with an 
average breeding density of 0.3–0.9 breeding pairs per 100  km2. The 
highest density was recorded at Dravsko polje with 0.6–2.2 breeding pairs 
per 100  km2. If possible breeding (breeding attempts) were also taken 
into consideration, the estimate would be up to five breeding pairs higher. 
The species was recorded at known breeding sites in most years after the 
breeding was confirmed. Black Kites were observed closer to larger water 
bodies and to rubbish tips than expected by chance. More Black Kites 
were recorded in areas with a lower percentage of forest and arable land 
and a higher percentage of meadows, settlements and wetlands. 
Key words: breeding population, breeding density
Ključne besede: gnezdeča populacija, gnezditvena gostota
1. Introduction
The Black Kite Milvus migrans inhabits open 
landscapes of Europe, Asia, Africa and Australia 
(Del Hoyo et al. 1994). It inhabits almost all of 
Europe, with the exception of northern latitudes 
and most Mediterranean and Atlantic islands 
(Cramp 1998), representing around 11% of global 
range (BirdLife International 2018). The 
European population of Black Kite is estimated at 
81,200–109,000 pairs (BirdLife International 
2015), representing less than 24% of the global 
population (Birdlife international 2004). The 
largest European breeding populations are in Russia 
(30,000–50,000), France (22,500–26,300), Spain 
(2,500–10,000) and Germany (2,700–4,100). 
72
With the exception of Italy (700–1,200 pairs), 
our neighbouring countries have small breeding 
populations in the range of 50 to 500 pairs 
(Birdlife international 2004).
In the 19th and early 20th century, Black Kite 
was present in Slovenia, but was rare and with 
no breeding record (Freyer 1824, Schiavuzzi 
1883, Schulz 1890, Reiser 1925). It had the 
same status in the first half of the 20th century, 
when the species was a non-breeding visitor in NE 
Slovenia (Matvejev & Vasič 1973). Until 1990, 
when breeding was documented for the first time 
at Leško polje (Kozinc 1991), its breeding status 
in Slovenia was uncertain (Geister 1995). In 
1999, the second breeding pair was confirmed at 
the confluence of the Sava and Ljubljanica Rivers 
(hereinafter referred to as “Confluence”), central 
Slovenia (Košir 1997, Kozamernik 2000), with 
the breeding population estimated at 1–3 breeding 
pairs at that time (Birdlife international 
2004). Between 2000 and 2011, several breeding 
pairs were confirmed or considered probable. 
Confirmations were as follows: at Medvedce 
water reservoir in 2004 (hereinafter referred to 
as “Medvedce”; Kerček 2005, Bordjan & Božič 
2009), in the Vipava valley in 2008 (Figelj 2007a), 
second and third pairs at Dravsko polje in 2009 
and 2011. Nest building was observed near Žovnek 
water reservoir in 2009 (J. Novak pers. comm.). 
In 2011, the breeding population was estimated 
at 10–20 breeding pairs (Denac et al. 2011). 
Thereupon, breeding was confirmed in the eastern 
part of Ljubljansko barje (Denac 2016). 
In Slovenia, Birds of Prey (Accipitriformes 
and Falconiformes) were mostly included in 
multiple species studies (e.g. Kmecl & Rižner 
1993, Gregori & Šere 2005, Bordjan & Božič 
2009, Škornik 2012, Bordjan 2012, 2015) and 
only rarely did they constitute a central part of 
study. Thus in more than 30 years of Acrocephalus 
magazine, there are only 19 articles with Birds of 
Prey as a central part of study, with most of them 
covering local problems of distribution (Bračko 
1990, 1998, Božič 1992, Gjerkeš & Lipej 1992, 
Trebušak et al. 1999, Mihelič & Brajnik 2006, 
Figelj 2007b, Denac 2010) or nesting (Smerdu 
1981, Škornik 1985, Kozinc 1991, Marenče 
1998). One deals with the bird’s diet (Kozinc 
1999), one with conservation (Luskovec 1990) 
and one with unusual influx (Hanžel 2015). 
Considering all our journals, papers on Griffon 
Vulture Gyps fulvus (Mihelič & Genero 2005), 
White-tailed Eagle Haliaeetus albicilla (Vrezec 
et al. 2009), Common Kestrel Falco tinnunculus 
(Šumrada & Hanžel 2012) and Red Kite Milvus 
milvus (Bordjan 2017) submit a more detailed 
review of the status of certain birds of prey in 
Slovenia. Moreover, in the past 50 years, out of 38 
Raptor species (also including Birds of Prey) 71% 
were part of a monitoring scheme and only 18% 
of species were part of national monitoring, while 
others were included in more or less local studies 
(Vrezec 2012). The purpose of this article is to 
give a more detailed overview of the Black Kite’s 
distribution, phenology, breeding population 
development and habitat in Slovenia in the light of 
new knowledge and data.
2. Methods
Data on the Black Kite in Slovenia was obtained 
from the ornithological literature, as well as directly 
from observers. All volumes of the following 
journals were checked: Acrocephalus, Biota, Falco 
and Svet ptic up to and including the last issue 
published in 2017. Additionally, Google Scholar 
was used with key words “Črni škarnik” and 
“Milvus migrans” or “Black Kite” for Slovenia. Data 
from online data base NOAGS (Atlas ptic 2018) 
were obtained. Observations were also collected 
directly and indirectly from other observers. 
Data till the end of 2017 were used for temporal 
and spatial distribution, but for breeding the 
2018 breeding season was included as well. Data 
were drawn in map using program ArcGis 10.4.1 
(ESRI 2015) and also used to calculate altitude 
and distance to the nearest large water body (rivers 
and lakes or fishponds with min. 3  ha of water 
surface), rubbish dump and settlements. Data on 
altitude were clustered in 100 meter groups to mask 
potential discrepancies between actual observation 
and point in the map. For breeding distribution 
coarser, 10x10  km squares were used, as well as 
smaller 2x2  km squares for habitat analysis. All 
entered points were overlaid with the 2x2 km grid 
(containing 5,405 squares) and percentage of land 
use (MKGP 2017) was calculated for squares with 
Black Kite observations (1,021 observations in 184 
D. Bordjan: Black Kite Milvus migrans in Slovenia – its distribution, phenology, breeding and habitat
73
squares). For habitat analysis, 1,100 random points 
were generated in Arc GIS in 2x2  km grid, and 
those that were outside Slovenia were later removed 
(amounting to 1,090 points in 1,000 2x2  km 
squares). Distance to large water body, rubbish 
dump and settlements and share of land use was 
calculated for random points and 2x2  km squares 
with random points. For labelling breeding status, 
confirmed and probable breeding was used. Data 
were labelled as confirmed breeding in proximity 
of known nest sites or when one or two individuals 
remained in the same area for longer period (two or 
more observations distanced at least one month) 
in combination with courtship display, copulation, 
observation of fledged young (together with parents 
up to first half of August) or regular (at least two 
observations at least one week apart in breeding 
period) flights to a potential nest site. Observations 
were labelled as probable breeding when one or 
two individuals remained in the same area for a 
longer period within main breeding period (20 
May–25 July), or observation of courtship display 
or copulation with the absence of later observations. 
Exception is the area of Krška ravan where breeding 
status given by Denac et al. (2009) was used. 
Observations in the western part of the Vipava valley 
were separated due to distance between two clusters 
of observations that are located more than 10  km 
from known nest site. Although Black Kites may go 
as far as 20 km from the nest in search of food during 
nesting, most feeding flights are made within 10 km 
from nest (Meyburg & Meyburg 2009). For the 
purpose of seasonal dynamics, we distributed data in 
37 ten-day periods that are explained in more detail 
by Bordjan & Božič (2009). A regular monitoring 
of waterbirds and birds of prey has been conducted 
at Medvedce since 2002 (Bordjan & Božič 2009) 
and Rački ribniki – Požeg Country Park since 2011. 
From study at Medvedce, the average temporal 
distribution of Black Kite presence per visit was 
calculated in a ten-day period.
3. Results
3.1. Temporal distribution
We gathered data on 1,388 individuals between 
1984 and 2017 (Figure 1). 70.7% of observations 
come from Dravsko polje and 61.5% from the 
breeding site at Medvedce. The number of observed 
Black Kites rose steadily with 7.6 individuals per 
year before 2001 and 124.4 between 2011 and 2017 
(Pearson’s r: 0.84; N = 32; P < 0.001). Even without 
individuals from Medvedce, the number of obser-
vations rose from average 7.3 to 20.1 individuals per 
year (Pearson’s r: 0.61; N = 32; P < 0.001). Most 
observations (1,021) involved single individuals 
(780) with more than ten individuals simultane-
ously observed only three times; 12 individuals 
were observed at Ljubljana rubbish dump (central 
Slovenia), 15 near Kromberk (Gorica, SW Slovenia) 
and 16 around Medvedce (NE Slovenia). 
Black Kite was present in Slovenia between 
mid-March and the beginning of December 
(Figure 2). The earliest observation dates to 14 
Mar when one individual was observed near 
Maribor (NE Slovenia) in 2002 (Lončar 2003) 
and one at Ljubljansko barje (central Slovenia) in 
2009 (Rubinić pers. comm.). Spring migration in 
Slovenia was weak in March and the number of 
observations peaked in May (Figure 2). In Slovenia, 
the maximum of observed individuals dates to mid-
May. After the spring migration peak, observations 
decreased steadily until the beginning of October 
with some observations made between the end 
of October and December (Figure 2). The latest 
observation was from 8 Dec at Lake Cerknica 
(A. Škoberne & M. Cvetko pers. comm.). 
The seasonal distribution was monitored 
more closely on breeding grounds at Medvedce 
(NE Slovenia) in 2002–2018. Black Kites were 
present continuously between mid-March and 
late September (Figure 3) with one observation 
in November (Bordjan 2004). The probability 
of observing a Black Kite at Medvedce in this 
particular period was on average 0.47 observations 
per visit and varied widely from 0.04–0.71 obs / visit 
(Figure 3). It was highest between late April and late 
July. Lowest probability was in 2002 (0.17 obs / visit) 
and in 2008 (0.25 obs. / visit) and highest in 2018 
(0.63 obs. / visit). 
3.2. Spatial distribution
Black Kite was observed in 71 out of 238 10x10 km 
squares covering Slovenia (29.8%; Figure 4). Ob-
servations were made in most flatlands of Slovenia 
with the exception of land around the Mura river.
Acrocephalus 39 (178/179): 71–83, 2018
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Figure 1: Number of Black Kites Milvus migrans observed between 1984 and 2017 in Slovenia. Black columns refer 
to observations at Medvedce water reservoir (NE Slovenia) and grey to observations from the rest of Slovenia).
Slika 1: Število črnih škarnikov Milvus migrans, opazovanih med letoma 1984 in 2017 v Sloveniji. Črni stolpci 
ponazarjajo opazovanja z zadrževalnika Medvedce (SV Slovenija), sivi pa opazovanja iz preostale Slovenije.
Figure 2: Number of Black Kites Milvus migrans observed in separate 10-day periods in Slovenia
Slika 2: Število črnih škarnikov Milvus migrans, opazovanih po posameznih dekadah v Sloveniji
No
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D. Bordjan: Black Kite Milvus migrans in Slovenia – its distribution, phenology, breeding and habitat
75
Highest densities of observations were recorded 
in the squares with confirmed breeding sites and 
squares with higher observation effort (i.e. Lake 
Cerknica). Black Kite observations were missing 
from extensive forested and mountainous areas.
Black Kite was recorded on the Slovenian 
coast in Sečovlje saltpans at sea level (Jančar 
1991, Sovinc & Šere 1993). Highest altitude was 
recorded during bird of prey count on Breginjski 
stol in 2010 (Denac 2010) just below 1,600  m 
a.s.l. Only eight records were made above 1,000 m 
a.s.l. Average altitude of Black Kite observations 
is 271  m a.s.l. and 309  m a.s.l., if Medvedce data 
are excluded. Black Kites were observed more often 
than would be expected at random below 300  m 
a.s.l. (Figure 5).
3.3. Breeding of Black Kite Milvus migrans in 
Slovenia
Between 1990 and 2018, ten confirmed breeding 
pairs were observed at seven sites (Figure 6). Three 
were observed only in a single year. The observa-
tions indicate that pairs at the confirmed breeding 
sites bred there more or less regularly (Figure 6), 
with above mentioned exceptions and Leško polje 
where breeding data were absent for 22 years. The 
only pairs that were observed at breeding sites 
continuously were those at Medvedce and in Rački 
ribniki  – Požeg Country Park, both with regular 
monitoring. From 2005 onwards, 3–7 pairs were 
registered in any given year.
In Slovenia, eleven pairs at nine sites meet 
criteria for probable breeding (Figure 7). With 
the exception of western part of the Vipava valley, 
N part of Ljubljana basin and NE part of Dravsko 
polje, the observations of Black Kites were more 
irregular then those for confirmed pairs. From 
2000 onward, 0–6 probable pairs were observed in 
any given year. 
The breeding population of Black Kites 
(considering confirmed and probable pairs in any 
given year) has risen steadily from 1–4 breeding 
pairs between 1990 and 2000 to 2–11 pairs 
in 2000–2010 and 6–12 pairs in 2011–2018 
(Figure 6). The 10 confirmed or probable pairs 
Figure 3: Seasonal dynamics of Black Kite Milvus migrans at Medvedce water reservoir (NE Slovenia) during 10-day 
periods between 2002 and 2010
Slika 3: Sezonska dinamika opazovanj črnega škarnika Milvus migrans na zadrževalniku Medvedce (SV Slovenija) po 
dekadah v obdobju 2002–2010
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Acrocephalus 39 (178/179): 71–83, 2018
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Figure 4: Distribution of Black Kite Milvus migrans in Slovenia with the number of observations in 10x10 km 
squares
Slika 4: Razširjenost črnega škarnika Milvus migrans v Sloveniji s prikazom števila opazovanj po posameznih 
kvadratih 10x10 km
Figure 5: Distribution of Black Kite Milvus migrans in altitude belts compared to available area per altitudinal belt 
including data from Medvedce water reservoir (white) and without (black) 
Slika 5: Razširjenost črnega škarnika Milvus migrans po nadmorskih pasovih glede na razpoložljivo površino 
posameznega nadmorskega pasu, vključujoč podatke z zadrževalnika Medvedce (belo) in brez (črno)
Al
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D. Bordjan: Black Kite Milvus migrans in Slovenia – its distribution, phenology, breeding and habitat
77
Figure 6: Yearly presence of Black Kites Milvus migrans at confirmed breeding sites
Slika 6: Pojavljanje črnega škarnika Milvus migrans na potrjenih gnezdiščih v posameznih letih
Figure 7: Yearly presence of Black Kites Milvus migrans at probable breeding sites
Slika 7: Pojavljanje črnega škarnika Milvus migrans na verjetnih gnezdiščih v posameznih letih
Landscape Park Rački ribniki - Požeg 2
Water reservoir Medvedce 3
Ljubljana Marshes (E)
Landscape Park Rački ribniki - Požeg 1
Water reservoir Žovnek
Water reservoir Medvedce 2
Vipava valley (W)
Water reservoir Medvedce 1
Confluence of Sava and Ljubljanica rivers
Leško polje
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Krška ravan 2
Bela krajina
Vipava valley (W)
Ljubljana valley (N)
Dramlje
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Ljubljana Marshes (W)
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Acrocephalus 39 (178/179): 71–83, 2018
78
from the past ten years can be considered regular 
breeders, and as there was a total of 21 confirmed 
or probable breeding pairs, the population was 
estimated at 10–21 breeding pairs in Slovenia.
The breeding distribution is shown in figure 
9. From the first observation of possible breeding 
in 1987 to the estimated breeding population in 
2018, the population has been estimated to rise by 
0.34 pairs/year (Figure 8). The average breeding 
density of Black Kites is 0.3–0.9 bp/100  km2 
with the highest at Dravsko polje, i.e. 0.6–2.2 
bp/100  km2 (Table 1). No semi-colonial breeding 
was observed. Closest nests were little less than five 
kilometres apart for three pairs near Medvedce in 
2018.
3.4. Habitat
Black Kite observations were recorded closer 
to larger water bodies and rubbish dumps 
than expected from random points, but not to 
settlements (Table 2). Black Kites were observed 
in squares with less forest cover than would be 
expected (Table 2). More than half (58%) of all 
2x2 km squares with Black Kite observations had 
less than 25% of forest cover and 85% of less than 
50% as opposed to squares with random points 
(15% and 38%). Also, Black Kites were observed 
more often in squares with higher share of arable 
land (on average arable land covered 28% 2x2 km 
squares), meadows (24%), urban area (11%) and 
wetlands (3%; Table 2).
4. Discussion
The number of observed Black Kites and their 
breeding population in Slovenia rose during the 
past three decades to 10–21 breeding pairs and more 
than 120 observations per year on average. This 
trend is similar to that in Carinthia (Petutsching 
& Probst 2017), but could merely reflect a trend 
in our knowledge of breeding population in 
Slovenia and also the intensified observation 
effort with surveys for the national Breeding Bird 
Atlas (Mihelič 2002), Natura 2000 Monitoring 
Schemes (Mihelič 2005), Farmland Bird Index 
(Božič 2007), local monitoring schemes; i.e. 
Medvedce (Bordjan & Božič 2009), Lake 
Cerknica (Bordjan 2012), accumulations on the 
Drava river (L. Božič pers. comm.) and new available 
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Figure 8: The dynamics of Black Kite Milvus migrans breeding pair numbers in Slovenia. Data includes confirmed 
and probable breeding attempts as well as possible breeding at otherwise confirmed breeding sites.
Slika 8: Dinamika števila gnezdečih črnih škarnikov Milvus migrans v Sloveniji. Podatki vključujejo potrjene in 
verjetne pare ter možne pare na sicer potrjenih gnezdiščih.
Year / Leto
D. Bordjan: Black Kite Milvus migrans in Slovenia – its distribution, phenology, breeding and habitat
79
Figure 9: Breeding distribution of Black Kite Milvus migrans in Slovenia of confirmed (red) and probable breeding 
pairs (yellow) in 10x10 km squares
Slika 9: Razširjenost potrjenih (rdeče) in verjetnih (rumeno) gnezdečih parov črnega škarnika Milvus migrans 
v Sloveniji v kvadratih 10x10 km
Table 2: T-test values between habitat variables of Black Kite Milvus migrans observations (N = 1482) and random 
points (N = 1090). Area represents an average share of individual land uses per 2x2 km square. 
Tabela 2: Rezultati T-testa med habitatnimi spremenljivkami opazovanj črnih škarnikov Milvus migrans (N = 1482) 
ter naključnih točk (N = 1090). Površina ponazarja delež povprečne rabe na kvadrat 2x2 km. 
Random Black Kite
t-value PMean SD Mean SD
Distance
[m]
Large water body 3621.7 2698.4 1176.4 1523.7 18.56 < 0.01
Rubbish dump 9981.4 5164.1 6097.4 3520.3 14.95 < 0.01
Settlement 367.8 382.9 396.6 350.3 -1.39 0.16
Area
Arable land 0.10 0.18 0.28 0.24 -12.28 < 0.01
Meadows 0.19 0.14 0.24 0.18 -4.35 < 0.01
Forest 0.57 0.27 0.25 0.22 15.02 < 0.01
Urban area 0.05 0.08 0.11 0.14 -7.92 < 0.01
Wetland 0.01 0.03 0.03 0.07 -8.10 < 0.01
Other 0.08 0.10 0.08 0.09 -0.73 0.46
Acrocephalus 39 (178/179): 71–83, 2018
80
databases (Mihelič 2016). This is possible since 
it is in contradiction with the broader European 
trend, where the breeding population suffered a 
substantial decline in the past century (Viñuela 
& Sunyer 1994, Birdlife International 2004) 
and its current trend is uncertain (BirdLife In-
ternational 2015). On the other hand at least 
locally, i.e. Dravsko polje, the population has risen 
substantially (from 1 to 7 pairs) and it may be 
similar to the population increase in Sicily (Sará 
2003) that does not reflect national trend in Italy 
(Sergio & Boto 1999), where negative trends 
prevail (Sergio et al. 2003). Similarly, the trend 
differs in different parts of Austria with Carinthian 
population rising (Petutsching & Probst 2017) 
and the population in Donau-Auen National Park 
decreasing (Probst & Schuhbauer 2010). Overall 
it seems that the population trend in Slovenia is at 
least stable, with some local increases. The estimate 
of breeding population is similar to the one given 
by Denac et al. (2011) but includes only confirmed 
and probable and not possible breeding pairs. With 
the latter, the estimate would probably be higher by 
up to 5 pairs. 
In Slovenia, Black Kite habitat is similar to 
habitat requirements in other countries, i.e. low 
forest cover and proximity to wetlands (Cramp 
1998, Probst & Schuhbauer 2010). Wetlands 
and large water bodies that are rich in food are 
essential for Black Kite (Sergio et al. 2003, 2005) 
with increased breeding density and success in their 
proximity (Sergio & Boto 1999, Salvati et al. 
2001, Sergio et al. 2003). Fish are important part 
of the Black Kite’s diet (Probst & Schuhbauer 
2010). Thus it is not surprising that most of our 
records were made at or near wetlands. The breeding 
density even rises with the size of wetland, but also 
with the size of open land (Sergio et al. 2005), as is 
the case in Slovenia. Open rubbish dumps represent 
important feeding areas for Black Kite (Blanco 
1994) and most of our breeding pairs include one 
in their territory. 
If the Black Kite’s absence from the Alps (N 
and NW Slovenia) and hills of W, S and E Slovenia 
(hills of Zasavje, Snežnik, Kočevje, Polhograjsko, 
Škofjeloško and Cerkljansko) could be explained 
with higher altitudes and forest cover (Cramp 1998), 
the reason for its absence from Pomurje is more 
complex. Almost complete absence of observations 
in apparently suitable habitat (low altitude and 
open mosaic landscape with many water bodies) 
in NE Slovenia is somewhat surprising. There were 
only few records indicating possible breeding along 
the lower Mura River so far (i.e. Božič 1998). One 
of the reasons may lie in arable land, since Black 
Kites tend to avoid intensive farmland (Tanferna 
et al. 2013) and their breeding density decreases 
with the size of intensive arable land (Sergio et 
al. 2003). On the other hand, Dravsko polje is 
also known for its ample intensively farmed land, 
but this may be compensated with many shallow 
fishponds and drainage ditches. One explanation 
may be that colonisation has not reached Pomurje 
as yet. It is increasing on Dravsko polje but it is still 
rare in Styria, Austria (R. Probst pers. comm.).
Although Black Kite can cross high mountains 
on its migration (R. Probst pers. comm.), it is a 
lowland species (Salvati et al. 2001), which is 
also in agreement with observations in Slovenia. 
In Northern Italy, Black Kite breeds between 
240 and 870  m a.s.l. with average at 515  m a.s.l. 
(Sergio & Boto 1999), although breeding density 
rises with lowering altitude (Sergio et al. 2003). 
In Switzerland, most pairs breed below 600  m 
a.s.l., and individuals observed higher in the Alps 
are thought to be non-breeding individuals on 
foraging trips (Schmid et al 1998), just like those 
on Breginjski stol (Denac 2010).
Migrating individuals in March correspond 
to peak migration across the Strait of Gibraltar 
and Suez (Panuccio et al. 2014). Similar to the 
central Mediterranean (Panuccio & Agostini 
2010), the spring migration in Slovenia is weak in 
March, but unlike the Straight of Messina it does 
not peak in mid-April (Corso 2001), but rather in 
May. It is often difficult to separate breeding from 
migrating individuals, especially as the percentage 
of immature individuals is significant during the 
second part of migration (Panuccio & Agostini 
2010). Seasonal dynamics differs from that in 
Algeria, where peak in the number of individuals 
is in August but similarly, Black Kites leave their 
breeding area at the end of September (Boumaaza 
et al. 2016). Although no Black Kites were observed 
in winter, such observations are expected in the 
future since wintering population is increasing in 
Europe, including all our neighbouring countries 
(Literák et al. 2017).
D. Bordjan: Black Kite Milvus migrans in Slovenia – its distribution, phenology, breeding and habitat
81
5. Povzetek
Med letoma 1984 in 2017 je bilo opazovanih 1388 
osebkov črnega škarnika večinoma po nižinah z 
glavnino opazovanj na Dravskem polju (70,0  %). 
Opazovanja so razporejena od morske gladine do 
nekaj pod 1600  m  n.m. s povprečno nadmorsko 
višino 271  m. Črni škarnik se v Sloveniji pojavlja 
med sredino marca in začetkom decembra z 
neizrazito spomladansko in jesensko selitvijo. 
Največje število opazovanj je v maju. Črni škarnik 
je bil opazovan v 71 od 238 kvadratih 10 x10 km 
(29,8 %), z večjim deležem opazovanj na gnezdiščih 
in območjih z večjim številom opazovalnih dni. 
Tako število opazovanj v posameznem letu kot tudi 
število potrjenih in verjetnih gnezdečih parov je v 
Sloveniji naraščalo. V  obdobju 2011–2018 je bilo 
najdenih 10 gnezdečih parov na sedmih lokacijah 
(3–7 v vsakem letu). Ob teh je bilo najdenih še 11 
verjetno gnezdečih parov na devetih lokacijah (0–6 
v vsakem letu). Gnezdeča populacija v obdobju 
2011–2018 šteje 10–21 verjetno in potrjeno 
gnezdečih parov s povprečno gnezditveno gostoto 
0,3–0,9 gp/100  km2. Najvišja gostota parov je 
na Dravskem polju (0,6–2,2 gp/100km2). Ob 
upoštevanju možnih gnezditev bi bila ocena višja za 
do 5 gp. Na potrjenih gnezdiščih je gnezdil v večini 
let po potrditvi, najbolj konstantno na območju 
rednih monitoringov vodnih ptic in ujed. Črni 
škarnik je pogosteje opazovan ob večjih vodnih 
telesih in bližje smetiščem, kot bi pričakovali 
naključno. Hkrati so bila opazovanja razporejena 
na območjih z nižjim deležem gozda in njivskih 
površin ter z višjim deležem travnikov, naselij in 
mokrišč.
Acknowledgments
My special thanks are due to Tomaž Mihelič for 
exporting data on Black Kite from online data base. 
I am also indebted to all who unselfishly shared 
their observations with me to enrich knowledge 
on the species. List of contributors in alphabetical 
order: Basle T., Bernard G., Blažič B., Bombek D., 
Božič L., Cvetko M., Denac D., Denac K., Denac 
M., Domanjko G., Fekonja D., Figelj A., Figelj J., 
Gamser M., Gjergjek R., de Groot M., Hanžel J., 
Horvat E., Jančar A., Jančar T., Kerček M., Kmecl 
P., Koren A., Kotnik A., Kozina A., Martinc U., 
Mihelič B., Mihelič R., Mihelič T., Mlakar M.M., 
Novak J., Ploj A., Poljanec L., Poljanec N., Premzl 
M., Remžgar T., Rijavec A., Rubinić B., Sešlar M., 
Slameršek A., Šalamun Ž., Šinigoj E., Škoberne A., 
Tomažič A., Tome D., Vrezec A., Vukelič E.
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Prispelo / Arrived: 11. 9. 2018
Sprejeto / Accepted: 28. 12. 2018
Acrocephalus 39 (178/179): 71–83, 2018