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