DOLOMITES - Annexes 2-8 - Provincia di Udine

NOMINATION OF THE DOLOMITES FOR INSCRIPTION ON THE WORLD NATURAL HERITAGE LIST UNESCO
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origins of the Dolomite fauna
Following the criteria of a recent analysis of the fauna that can be recognized in the animal population
of the entire Alpine chain (Chemini and Vigna Taglianti 2002), we can see six distinct groups
represented of Dolomite fauna.
Species endemic to the Alps.
While the southern edge of the Alps plays host, especially in the area of cave-dwelling fauna, to several
species of very specifically localized distribution whose origins can be traced back to antiquity,
this component is lacking in the innermost belt of the Alpine chain due to the severity of the weather
conditions that it was subjected to during the Pleistocene age. Here, we find several localized (endemic)
species of a more recent origin. This category includes species exclusive to the Alpine chain or
a portion of it, which subsist mainly in the medium to higher elevations and which have originated
by geographic isolation with respect to similar species that remained allocated in other mountain regions
of Eurasia, between the end of the Pliocene and the Pleistocene eras. Among the vertebrates,
this fauna sector in the Dolomites is represented by the black salamander (S. atra), but the invertebrates
are even more numerous. Among these, several species of ground beetles of the Carabus genus,
such as C. (Orinocarabus) adamellicola, C. (O.) alpestris dolomitanus and C. (Orinocarabus) bertolinii.
These belong to a group of species whose distribution areas, complex and partly overlapping, are the
result of complicated paleogeographic and paleoclimatic events that involved the fauna of the high
Alpine elevations. Numerous other species of beetles are found in geographic areas of the same type,
for example, in the genera of Nebria, Trechus, Simplocaria, Dichotrachelus, Otiorhynchus and Oreina.
Glacial relicts of the massifs de réfuge.
Even during the coldest glacial phases of the Quaternary era, the Alpine and Prealpine regions had
never been completely covered with glaciers. Here, there were areas that acted as “refuge massifs”
where several animal (and plant) populations that were better able to withstand the harshness of the
weather conditions managed to survive. The isolation experienced by these populations, even for
short periods of time – on a geological scale - has often led to their differentiation on a sub-specific
or specific level. This is proven today by the existence of species of a very narrow distribution which
still live in these refugia. These species are represented mainly in the Prealps belt, but are also found
in the southernmost limit of the Dolomites.
Boreoalpine species.
The characteristic present-day fragmented and even punctiform geographic distribution of the species
referred to in this group of fauna is the result of the glaciers pulling back at the end of the last
glacial age, which took place between 15,000 and 10,000 years ago. The previous advancement of
the glaciers southward pushed the animal (and plant) life toward more southern latitudes, where other
natural geographic barriers stopped the flow. For many species, the peninsula of Italy - as in the
other great Mediterranean peninsulas - represented a refuge where they were able to survive during
the glacial maximum periods and which became a new starting point in their subsequent colonization
of Central and Northern Europe. The prevalent parallel orientation of the Alps represented a
formidable obstacle to the recolonization which carried northward numerous species surviving the
glacial maximum periods. Several populations remained at the higher elevations in these mountains.
In some cases, migration would begin in one southern refuge area and split along the way, giving
rise to population settlements in the Alps, including the Dolomites, above the upper limit of the
treeline, and at the same time, to populations that continued their advancement toward Scandinavia,
but without making any stable colonies in Central Europe. These were species well adapted to
life in the colder climates (periglacial and similar), whose distributional range is split into two parts,
separated by an enormous distance. The first is a northern area, generally circumscribed to one part