Vol. 32 – 2006 - Ecologia Mediterranea

zones of the steppe range play a pivotal role
for the present population and need to be the
focus of conservation efforts. These zones are
called “Priority Zones”.
The focus on the lesser kestrel is supported by
several reasons. First, it is a top predator and
presumably prevents the demographic explosion
of several phytophagous populations and,
in a broader sense, it influences the regulating
mechanisms of the entire ecosystem. Second,
it has a high international conservation
value (BirdLife International 2004). Third, the
studied area accounts for 70-80% of the total
Italian population (the fourth largest in
Europe), highlighting its importance for
national and international conservation programmes
(Palumbo 2001). Fourth, the lesser
kestrel is recognized as a good target species
for conservation strategies in this kind of
habitat (Tella et al. 1998). Fifth, raptors are
considered indicators of habitat quality and
their inclusion in management and conservation
plans has been already recommended
(Newton 1979; Rodriguez-Estrella et al.
1998).
Study site
The National Park of Alta Murgia and the
Regional Park of Murge Materane (Figures 1a
and 1b) lie in the Murge district, a low mountain
range (Torre Disperata 687 m a.s.l.;
Monte Caccia 679 m a.s.l.) in south east Italy.
The parks offer typical karstic landscapes,
slightly hilly with crops and small and
degraded oak woods at lower altitude and
large areas of pastures and sown lands.
Human settlements are concentrated but the
towns are far one from one another and connected
by a limited, large-mesh road network;
landscape porosity is greater than that of
nearby landscapes (Mininni 1996). The pastures
consist of wide expanses of Mediterranean
steppe grasslands, recently described
by a new endemic alliance, Hippocrepido
glaucae Stipion austroitalicae Forte et Terzi
(Forte et al. 2005), of Scorzonero Chrysopogonetalia
Horvati et Horvat (1956) 1958
(class Festuco Brometea Br.-Bl. et Tx. 1943).
This type of vegetation has been variously
termed with “pseudo steppe”, “seminatural
grassland”, “Mediterranean steppe”, “substeppe”
and so on. We have preferred to refer
to it as “Mediterranean steppe grassland”, or
in abbreviated forms as “steppe grassland” or
ecologia mediterranea – Vol. 32 – 2006
Priority Zones for Mediterranean protected agro sylvo pastoral landscapes
“steppe”, with the aim of indicating grasslands
in a Mediterranean bioclimate dominated
by perennial caespitose grasses, spaced
or not, and populated in particular by xerophytes.
Lesser kestrel
The lesser kestrel is a migratory falcon with
a Palearctic breeding distribution (Biber
1996). Apart a small number of residents in
the south of Spain, the main winter quarters
of the European population are in Africa
(Tella & Forero 2000). The lesser kestrel used
to be one of the most common birds of prey
on the European continent. However, in the
second half of the last century, its population
suffered a dramatic decline (Tella et al. 1998;
Biber 1996). It is now included in the IUCN
Red List of Threatened Species with the status
of “vulnerable” because the world population
has probably declined by more than
30% in the last 10 years and a similar trend is
predicted for the coming decade (BirdLife
International 2004). This species is mentioned
in Annex I of the Bird Directive, and also in
the Bern Convention, Bonn Convention,
CITES and in the African Convention on the
Conservation of Nature and Natural
Resources. The main ecological causes of the
population decline have been identified in the
relatively recent changes in structural (and
functional) aspects of the rural landscapes
inhabited by this falcon. The reduction in the
extent and quality of its foraging area is considered
the main cause of its demographic
trend (Donazar et al. 1993; Parr et al. 1995;
Biber 1996; Bustamante 1997; Tella et al.
1998; Liven-Schulman et al. 2004; Franco &
Sutherland 2004). The lesser kestrel prefers
warm or hot areas with short vegetation, such
as pastures and steppe-like habitats, where it
can easily find its prey, consisting of invertebrates
(Gryllidae, Acrididae, Tettigoniidae,
Gryllotalpidae and Coleoptera), chiefly large
Orthoptera and lizards and small mammals
(Biber 1996). The relationships between the
lesser kestrel and its foraging sites have been
studied by direct and indirect (radio-tracking
procedures) observations in different geographical
contexts (Donazar et al. 1993; Parr
et al. 1995, 1997; Bustamante 1997; Tella et
al. 1998; Franco & Sutherland 2004). All
those studies highlight the importance of
semi-natural grassland as a foraging site but
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