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Islands and plants: preservation and understanding of flora on Mediterranean islands

Fig.4. The progressive succession after abandonment of Pantelleria’s cultivated terraces
leads to a very fast recovery of shrubland and maquis communities (photo J. Rühl).

Grazing
Grazing and cattle management are important for nature conservation in
the circum-Sicilian islands, as exemplified by the vascular flora of Lampedusa.
The island hosts the only Italian populations of several “grazing-dependent”
plants like Colymbada acaulis and Echinops spinosissimus subsp. spinosus.
According to recent reports (La Mantia et al., 2009), the spread and survival of
the former species depends on grazing disturbance, while the rapid decrease of
the latter species correlates with the cessation of pastoral practices. Moreover,
Caralluma europaea subsp. europaea, Ophrys picta, and Oncostema dimartinoi
are “grazing-tolerant” in that they prefer open areas with more light and space
but suffer from overgrazing and mechanical damage caused by trampling.
Finally, overgrazing leads to the increasing extension of grasslands dominated
by poisonous geophytes like Charybdis maritima and Asphodelus ramosus and
the local endemic Thapsia pelagica (Brullo et al., 2009b); the latter species may
be indirectly favoured by high grazing pressure because of its low palatability.

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