Holarctic Marmots as a factor of Biodiversity.
Rumiantsev V.Yu;, Nikol'skii A.A. & Brandler O.V. eds.,
Abstracts, 3d Conference on Marmots (Cheboksary, Russia, 25-30 August 1997),
Moscow ABF 1997, 216p. ; 187-188.



LONG-TERM MONITORING OF A POPULATION OF MARMOTS IN THE NORTHERN APENNINES - PRELIMINARY DATA


L. Sala, P. Tongiorgi, M.Gianaroli, C. Sola, A. Spampanato Angela

Dipartimento di Biologia Animale, Modena, Italy


The alpine marmot, Marmota marmota, was introduced into the northern Apennines in the 1950's and 1960's and is now relatively common in an area distinct from its original alpine habitat. An initial study of this new population concerned its general distribution (Ferri et. al., 1988), while subsequent work has investigated social distribution, the space use and various behavioural aspects of the families occupying a 'sample' area (of about 5 hectares) on Monte Cimone (2,230 m above sea level) (Sala et. al., 1992, 1996). In order to carry out a long-term study of the density and the spatial and temporal dynamics of a broader range of settlements, the sample area was extended in 1995 to the entire upper area of the north face of Monte Cimone (more than 40 hectares), including the original 'sample' area.

The number and distribution of the families of marmots in the study area have been recorded in two crucial moments of every active season: at the beginning of May, i.e. shortly after the end of hibernation (which in the area is around 22-25 April), and in high summer when any offspring were also recorded. As far as the number and distribution of the animals is concerned, the results in successive years confirm the substantial stability noted in the course of the preceding observations. This stability may be attributable to the fact that the Apennine population has already saturated the available habitats, which are, in any case, extremely limited and concentrated in the small altitude range between the top of the tree line (1,600-1,700 m a.s.l) and the ridge (1,900-2,000 m a.s.l). The distribution of the hibernation and reproduction burrows is also stable over time: in 7 of the 10 territories observed, they remain unchanged, while in 3, they vary. Remembering that the extension of the study area led to the inclusion of zones which are unsuitable for settlement (exposed or very superficial rocks and covering of dense Vaccinium), the density of the families on the entire north face of Monte Cimone (on average, approximately 1 every 3.5 hectares) does not differ significantly from that in the 'sample' area (about 1 every 2.5 hectare). Over 44 active seasons/family, the average frequency of reproduction is 1 litter every 2.3 active seasons. The alternation between
reproductive and non-reproductive years confirms the situation already seen in families'5' and '6' since 1988 ('territory A' and 'territory B' in Sala et. al., 1996). Each family reproduces at most for 2 consecutive seasons, followed by a break of 1-3 years. It is interesting that despite the alternation between reproductive and non-reproductive phases, the overall number of litters each season in the study area does not fluctuate substantially.The families in the Monte Cimone study area are still being monitored, and the intention is to continue the study in the same way in the coming years, in order to have a historical series large enough to understand the population dynamics of the Apennine marmot. Although the animal is foreign to this environment, it has already become of interest for the Emilia Romagna Upper Apennines Park, both in terms of its ecological role in the food chain of the pasture (in particular as prey for the royal eagle and, occasionally, the wolf), and as a tourist attraction.

Table.

199419951996Years of observations
(n)
Litters (n)
Family territoryPresence of litterFamily territoryPresence of litterFamily territoryPresence of litter
1-1-1-4#1
2-2-2////31
2////3////3-32
4////4-4-31
5////5////5-4
5a (incl. in 5?)5a (incl. in 5?)5a////31
6////6-6////94
7-7////7-31
NDND7a (incl. in 7?)7////21
NDND8////8-21
NDND9-9ND10
NDND10////10////22
4419
Total active seasons/family territoriesTotal litters
//// Seasons with offspring; # Presence of offspring in 1993; 2 New family settlement (1993); ° Data available from 1988 (Sala et al. 1996); ND Data not available.


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