PhD in Biological Sciences and Applied Biotechnologies

Contacts

Supervisor

Antonio Rolando

Curriculum vitae

Curriculum Vitae

Phd thesis

 

The Alpine marmot as ecological indicator of environmental changes in mountain open habitats

The primary and secondary Alpine meadows have suffered a heavy pressure in recent decades. In the past this kind of habitat had greatly expanded thanks to the limiting effect against the forest exerted by man thought grazing of domestic livestock. A main result has been an increase in open areas, free of trees and shrubs, an habitat suitable for several species.  On the contrary, today we are witnessing the reversal of this phenomenon: the activity of grazing by domestic livestock is strongly decreasing in most mountainous regions. At low altitude, once grazing of domestic livestock is interrupted, open habitats turn to shrublands and, after years, into forests. This scenario ends with a progressive loss of open areas as a result of colonization by tree-shrub associations and a consequent decrease in the heterogeneity of the Alpine environment in the long term (MacDonald et al. 2000; Weiser 2007; Chamberlain et al. 2013; Ameztegui et al. 2016).

However, beyond areas evolving towards shrublands and forests following the abandonment of pastures, there are still many areas subject to strong grazing pressure for the presence of an excessive bovine or sheep load. To these changes, caused directly by human, are added the effects of climate change, which in the Alps results in a general shift of habitats along the altitudinal scale, due to rising temperature (Acquaotta et al. 2015). These effects presently result in an highly fragmented scenario characterized by fast changes in the Alpine environment, which is naturally inhabited by animal species very well adapted to its severe characteristics (e.g. low temperature, persistence of snow cover, limited season of fresh herbaceous species).

Wild animal species respond differently to these pressures; for example, it has been demonstrated that grassland bird species suffer a negative impact by the abandonment of grazing and the consequent loss of open habitats. These species are thus more and more confined at high altitude (Laiolo et al. 2004). In ungulates it has been shown that chamois tend to move at higher altitude when temperatures are too high (Mason et al. 2014).

 

The Alpine marmot (Marmota marmota) is a medium size rodent well distributed in the Alps and well adapted to live at high altitude. It inhabits areas of open meadows to the borders of forests, in an altitudinal range between 1500 and 2600 m a.s.l.. The wide distribution, the easy detectability of the animals, the herbivorous diet and the need for wide herbaceous environment make the Alpine marmot a 'model species'  to study the environmental changes currently in progress in alpine open habitats and the relative adaptations of animal species. Furthermore, the Alpine marmot offers other interesting characteristics to be monitored during a long-term project focused on ecological and behavioural adaptation to the environmental changes. The species is diurnal, it is active from April to September and hibernates during the winter. Alpine marmots live in family groups composed of one dominant parental breeding pair, their offspring and related or unrelated adult subordinates and yearlings. Families live on stables territories and family members move, interact and forage within a delimited and measurable home-rage (Pasquaretta et al. 2012; Ferrari 2013).  Each member of the family group has a 'role' (dominant, helper, subordinates) established through continuous social interactions with other family members. The family group is a main element for the survival of individuals during the active season, which is connected to the possibility to live and forage in a territory (Allainè, 2000). During winter marmots of a family hibernate all together in the same burrow and the presence of conspecifics increases the possibility of survival, especially for the young of the year (Allainè et al., 2000). 

The study area is located in Orvieille, Valsavarenche (Valle D'Aosta). Two main sites are under monitoring: the first one is at 2100 meters, it is characterized by moraine debris and closeness to the forest; the second one is at 2300 up to 2500 meters and it is characterized by open meadows. The two sites are relatively close together but can be considered as separate for the Alpine marmot since displacements between members of the families inhabiting the two different sites were rarely observed. Main differences between the two areas are the distance from the forest (which affect the marmots' vigilance behaviour, Ferrari et al. 2009), the altitude and the grazing pressure from domestic livestock. The lower area is inhabited by 9 to 11 families per year (families can merge or split in different years), while the higher area is inhabited by 10-13 families. Since 2007 (when the marking protocol of marmots started) around 60 individuals per year belonging to 25 different families (a total of 280 marmots) have been marked and monitored during the whole active season. Data on biometrics, ecology and behaviour have been collected on marked animals, including information on reproduction, survival and individual fitness.

The study is entering in its twelfth year and now the population time-series dataset is suitable to explore habitat selection and local adaptation by marmots to the  heterogeneous open landscape of the Alps. At this stage it will be also possible to evaluate the effects of environmental and climatic changes on the species local adaptation. The doctoral project will benefit of this large database and the field data collection will continue with the same methods along the PhD project, so to continue this long term study.

 

Objectives

Recent literature on marmot showed some biometric variations as adaptions to temperature rising (Ozgul et. al 2010; Armitage 2013), but no studies so far have been produced considering together local adaptations, changes in demographic parameters and individual fitness as consequences of the ongoing climatic and environmental changes.

1. Evaluating the influences of environmental, anthropic and climatic factors on the demography of the species.

The habitat used by the Alpine marmot is characterized by fast changes, due to the interaction between climate change, over-use of grasslands by domestic livestock, abandonment of pastures and the connected modifications. The Alpine marmot has to react to these environmental and anthropic pressures by adapting to changes in its natural environment. Nevertheless, when these pressures are too high and variations too deep, adaptation may result both in the abandonment of some areas or the colonization of new sites that may generate a dynamic pattern.

 

2.  Influence of environmental variables upon individual and family group characteristics

Considering the importance of sociality in the Alpine marmot, in this part of the project I want to investigate the influence, if any, of changes in environmental variables on the sociality and organization of family groups. 

Some references

 Acquaotta F., Fratianni S. and  Garzena D. "Temperature changes in the North-Western Italian Alps from 1961 to 2010". Theoretical Appllied Climatology. 2015, 122:3, 619-634.

Allainé D. "Sociality, mating system and reproductive skew in marmots: evidence and hypotheses". Behavioural Processes. 2000, 51:21-34.

Allainé D., Brondex F., Graziani L., Coulon J., Till-Bottraud I. "Male-biased sex ratio in litters of  Alpine marmots supports the helper repayment hypothesis". Behavioural Ecology. 2000 11:507-514

Ameztegui, A., Coll, L., Brotons, L. and Ninot, J. M. "Land-use legacies rather than climate change are driving the recent upward shift of the mountain tree line in the Pyrenees". Global Ecology and Biogeography, 25: 263-273.

Armitage K.B. "Climate change and the conservation of marmots". Natural Science. 2013; 5 :36-43.

Chamberlain D.E., Negro M., Caprio E. and Rolando A. "Assessing the sensitivity of alpine birds to potential future changes in habitat and climate to inform management strategies". Biological Conservation. 2013, 167: 127-135.

Ferrari C., Pasquaretta C., Carere C., Cavallone E., Hardenberg A., and Réale D. "Testing for the presence of coping styles in a wild mammal". Animal Behaviour 85: 1385-1396

Ferrari C., G. Bogliani, A. von Hardenberg. "Alpine marmots (Marmota marmota) adjust vigilance behaviour according to environmental characteristics of their surrounding". Ethology Ecology and Evolution. 2009 21: 355-364

Florant GL "Lipid metabolism in hibernators: The importance of essential fatty acids." American Zoologist. 1998, 38, 331-340.

Gerhard Wieser G., "Land Use Change and Mountain Biodiversity". Mountain Research and Development. 2007, 27 (2), 188-189.

Laiolo P, Dondero F, Ciliento E, Rolando A. "Consequences of pastoral abandonment for the structure and diversity of the alpine avifauna". Journal of Applied Ecology. 2004. 41: 294-304.

MacDonald D., Crabtree J.R., Wiesinger G., Dax T., Stmou N., Fleury P., Gutierrez Lazpita J. and Gibon A. "Agricultural abandonment in mountain areas of Europe: environmental consequences and policy response". Journal of Environmental Management. 2000, 59, 47-69

Mason T.,
 Stephens P. A., Apollonio M.and Stephen G. Willis. "Predicting potential responses to future climate in an alpine ungulate: interspecific interactions exceed climate effects". Global change biology. 2014, 20, (12), 3872-3882

Nelli L., Ferrari C. and Hardenebrg A. "Factors affecting Alpine marmot detectability in point transect distance sampling ", in prep.

Krebs J.C. and Singleton C.R. "Indices of condition for small mammals". Journal of Zoology. 1993, 41, 317-323

Ozgul A., Childs D., Oli M., Armitage K.B., Blumstein D.T., Olson L.E., Tuljapurkar S., Coulson T. "Coupled dynamics of body mass and population growth in response to environmental change". Nature. 2010, 482-485.

Pasquaretta C., Bogliani G., Ferrari C., Ranghetti L. and von Hardenberg A. "A New Method for the Accurate and Fast Visual Collection of Animal Locations". Wildlife Biology. 2012,18:2.

Pellicioli F. and C. Ferrari. "The use of point-transects distance sampling to estimate the density of   Alpine marmot in the Gran Paradiso National Park". Journal of Mountain Ecology. 2013. 9: 47-60

 

 

Research activities

Fall 2020

I am currently working on old data about marmot distribution in the past and current distribution in the last 3 years. Also I am working to extranc environmental variables which may explain the persistence or transietory of some marmots colonies.

 

Summer 2020

Summer 2020

 As for the most of us, I had to stop the field data collection during this year due to the pandemic situation. I already organized the studies with 6 students, but we had to cancel the entire session.

So i was only able to monitor by myself the survival of marked marmots and to census some areas, but far away from what I previously organized to do.

Thus I worked on the manuscript and analysis to develop and I followed some online courses. Unfortunately 3 conference I planned to partecipate were cancelled so I only took part to one virtual conference in August.

 

Manuscripts in progress

Marginal habitat provides unexpected benefit to Alpine marmot. Major revision requested from Oecologia.

Effects of intrinsic and extrinsic drivers of activity budgets in Alpine marmots;  Submitted to The Journal of Ethology.

Social network analysis of small social groups: methods and application in the Alpine marmot; submitted to Ethology.  

Inter Individual behavioral variation in the crested porcupine,  accepted to Mammalia

Abundance of Ixodidae ticks along  an altitudinal  gradient influences transmission risks of zoonotic Protozoa, in prep.

Old and recent distribution in the Alpine region of Marmota marmota, in prep-

 

 

Summer 2019

During this season I continued the routine field work of capture mark and observing marmots, but according to my thesis I am also working on the old distribution of the Alpine area in the protected area.

In fact my goal is to investigate if marmots moved from areas where they were living 30 years ago, maybe in relation to the different use of the land or the changes in forest presence.

So I have several area for which I know the historical precence -or absence- of marmots, and I am starting to visit these to confirm the presence or, on the contracy, certify the actual absence of this species.

In this context I start a collaboration with the French group of the University of Lyon and the Spanish group working on marmots in the Pyreneis. Our goal is to define a protocol to estimate a potential changes in Alpine marmot distribution.

Summer 2018

I worked in the capture and marking of Marmots and collected several observation about precense of marked individual in the study areas.

NUMBERS OF THE FIELD ACTIVITY 2018 

Started 27 April

Finished 8 Septmeber (15 days off in August)

Nr of captured marmots: 53

New individuals:24, of those 8 pups

Followed individuals 78

16 families

108 vegetation sampling for species composition

223 vegetation samples for near infrared spectroscopy

NUMBERS OF THE FIELD ACTIVITY 2018 

Started 27 April

Finished 8 Septmebr (15 days off in August)

Nr of captured marmots: 53

New individuals:24, of those 8 pups

Followed individuals 78

16 families

108 vegetation sampling for species composition

223 vegetation samples for near infrared spectroscopy

 Manuscript submitted February 2019

Disentangling extrinsic and intrinsic drivers of activity budgets in Alpine marmots, where, by comparing time budget of Alpine marmots families inhabiting the two different study areas, we investigated the time budget allocation driven by individual and ecological variables. I used 3515 observations on 67 marked individuals belonging to 12 different marmot families; these data have been collected in previous years. For the statistics I used the multinomial regression analysis  which allowed me to consider all the behaviors as unique variable accounting for repeated measures. 

 

Manuscript in progress July 2019

Different site different survival? Different effects of enviroment on Alpine marmot

 

 

My main activity in the field

Data collection mainly on the field: visiual observation, trapping and marking of marmots.

My main skills are related to the study of animal behavior in nature. 

Since 2006 I collaborate in the project about the Alpine marmot, which includes the monitoring of marmots behaviors and capture and marking of individuals.

During the field work we spend lots of time observing animals from far and reconizing them; we also collect data on behavior and on body mass gain.

During the capture we take measures of biometry, we collect sample about hormonal and genetics, but also about personality.

Here  a link about the project