Relazione tenuta in occasione della presentazione dei risultati del progetto di ricerca sull'habitat della Salamandra di Aurora e le sue relazioni con la gestione forestale

1. L’habitat della Salamandra e
i risultati dell’esperimento
Tommaso Sitzia
tommaso.sitzia@unipd.it
Asiago 15 Maggio 2018
Uomini, Boschi e Salamandre

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3. Amphibia-Reptilia 33 (2012): 541-543
The golden Alpine salamander (Salamandra atra aurorae) in
conservation peril
Described in 1982 as new taxon, the golden
Alpine salamander (Salamandra atra aurorae)
was one of the most unexpected and spectac-
ular herpetological discoveries for the Euro-
pean continent of the last century (fig. 1). These
unique salamanders are endemic to a very small
mountainous area located in the southern Alps
of Northern Italy, and are only known from a
few localities in the Altopiano dei Sette Co-
muni (province of Vicenza, Veneto region) and
the Altopiano di Vezzena (province of Trento).
Populations of the golden Alpine salamander
are geographically isolated from the remain-
ing populations of conspecific Alpine salaman-
ders (S. atra atra) and underwent a unique
evolutionary history. Golden Alpine salaman-
ders display remarkable differences concerning
colour pattern and genetic composition with re-
gard to other populations of Salamandra atra.
In particular, while known populations of S.
atra atra are uniformly black, the golden Alpine
salamander always displays yellow patches on
its dorsal side. To date, S. atra aurorae has
been only reported from a rather limited num-
ber of localities, and currently it is unclear
whether these sites are connected via disper-
sal/gene flow with each other. In contrast to
populations of Salamandra atra atra, the gol-
den Alpine salamander is considered to be crit-
ically endangered by the IUCN red list, under
criterion B1ab (iii) (http://www.iucnredlist.org/
details/19843/0), and is included as “priority
taxon” in the European Union Habitat directive
due to its very limited geographic distribution
and the potential threat of habitat loss resulting
from wood harvesting.
The Natura 2000 site “Altopiano dei Sette
Comuni” is of major importance for the pro-
tection and conservation of existing popula-
tions of S. a. aurorae. It includes the “Bosco
del Dosso” forest, a prime habitat for the gol-
den Alpine salamander. Until today, the popu-
lation at the Bosco del Dosso is supposed to
represent the largest known census size popu-
lation of S. a. aurorae. Despite the enor-
mous importance of this population, in May
Open petition for the conservation of the golden Alpine salamander in Italy
Habitat destruction through the use of heavy machines in the type locality of Salamandra atra aurorae at the Bosco
This figure is published in colour in the online version.
structive forestry works as well as
clearings have been noticed by field
heavy machines and a large number of trees,
particularly Silver Firs (Abies alba), have been
Figure 2. Habitat destruction through the use of heavy machines in the type locality of Salamandra atra aurorae at the
del Dosso. This figure is published in colour in the online version.
2012 destructive forestry works as well as
forestry clearings have been noticed by field
herpetologists at the Bosco del Dosso (fig. 2).
Additionally, trees marked for later clearances
were also observed (fig. 3). In detail, new
forestry paths and roads were built by using
heavy machines and a large number of
particularly Silver Firs (Abies alba), have
marked for removal in the near future. In t
cent past, the use of heavy machines for
harvesting, both in this and other similar
have had disastrous consequences incl
Figure 3. Trees that have been marked to be cut at the Bosco del Dosso. This figure is published in colour in the
version.

5. Salamandra atra aurorae Trevisan
• Endemico dell’Altopiano
• Anfibio elusivo e poco attivo
• Quiescente in inverno
• Viviparo, non associato all’acqua
• Lista rossa nazionale: vulnerabile
• 477 (± 184) individui / ha boschi
maturi
• 97 (± 23) individui / ha boschi
giovani
• Larghezza media home range: 7.8
m
• Distanza di ricattura massima: 30
m
• Vedi anche Bonato & Fracasso
(2003)

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9. 5 m 5 m
5 m
10 cm
x 82
x 50
9 ha

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11. Rilevamento della presenza e
dell’abbondanza degli individui
• Ricerca manuale diurna nei rifugi
• Ricerca all’alba
• Ricerca diurna dopo precipitazione
abbondante
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13. Bosco del Dosso (9 ha)
17/50 piante tagliate nel 2015

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15. Effetti del taglio ed esbosco
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Numerodiadultiperalbero
Pianta tagliata

16. Habitat
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Numerodiadultiperalbero(log)
Copertura di vegetazione Numero di alberi
giovani (log)

17. Finestra di operatività
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Temperatura del suolo
Altezza neve
Data di fusione
Altezzaneve[cm]
T[°C]
Nov Gen Mar Mag Lug Set
Fonte: ARPA Valle d’Aosta

18. Variabilità della copertura nevosa
• 1950-2009 (fonte: Valt & Cianfarra, 2010)
- durata della copertura nevosa: - 1,5 giorni / decade
- altezza cumulata di neve: - 2,10 cm / decade
- L’ultima decade è stata caratterizzata da un
andamento opposto rispetto a quello
osservato dagli anni ‘50, specialmente tra 800
e 1500 m s.l.m.
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Fonte: Valt, M., & Cianfarra, P. (2010). Recent snow cover
variability in the Italian Alps. Cold Regions Science and
Technology, 64(2), 146-157.
SAI = Standardized Anomaly Index (SAI = 0 se il valore corrisponde alla media del periodo)

20. Temperatura del suolo
Altezza neve
Data di fusione
Altezzaneve[cm]
T[°C]
Nov Gen Mar Mag Lug Set
Ampiezza della finestra
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21. Conclusioni
• Non sono emerse differenze significative tra il
campione trattato (soggetto a taglio ed esbosco)
e quello di controllo (non soggetto a intervento)
imputabili all’esbosco
• Alcuni elementi dell’habitat hanno mostrato
relazioni significative con l’abbondanza osservata
di individui: implicazioni gestionali
• L’ampiezza della foresta di operatività è
condizionata dagli andamenti del clima
• Ulteriori ricerche dovrebbero riguardare diverse
scale spaziali e temporali e altri periodi dell’anno
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