Seasonal and annual variation in the food habits of Apennine brown bears, central Italy

Abstract

Only scanty and outdated knowledge is available on the food habits of the Apennine brown bear (Ursus arctos marsicanus) population, despite its critical conservation status. Based on 2,359 scats, collected from June 2006 through December 2009, we documented seasonal and annual variation in the diet of this bear population within its 1,294 km2 core distribution in Abruzzo, Lazio and Molise National Park and its external buffer area in central Italy. Using correction factors to estimate digestible energy, we revealed substantial consumption of plant matter by bears, including herbaceous vegetation in spring (31.7 ± 25%) and early summer (19.0 ± 7%), a variety of naturally occurring berries in summer (56.5 ± 14%), and hard mast (66.9 ± 21%), largely supplemented by fleshy fruits (26.3 ± 18%), in the fall. Bears also consumed insects, mostly ants, in early summer (38.3 ± 7%), and wild ungulates in spring (10.2 ± 11%). Hard mast production strongly influenced year-to-year variation in the diet. High-quality foods, such as berries and other fleshy fruits, were increasingly consumed by bears in years of low to null hard mast productivity, suggesting that habitat productivity is currently high and diversified enough to allow bears to avoid the risk of nutritional stress during occasional hard mast failures. Nevertheless, as exemplified by a negative trend in late-summer consumption of buckthorn berries (Rhamnus spp.) by bears, our findings demonstrate the need to implement management strategies that will ensure long-term habitat productivity and provide optimal foraging opportunities for Apennine brown bears

Survival and divergence in a small group: The extraordinary genomic history of the endangered Apennine brown bear stragglers

“…We identify an active process of maintenance of variation at crucial genes for pathogen defense and chemical perception. We hypothesize that the lack of competitors reduced the impact of many deleterious mutations (67), and that the highly diversified diet of the brown bear may have compensated for the energy production problems in the Apennine population by facilitating a switch from omnivory to an almost completely vegetarian diet (68,69). In addition, we inferred a genetic component related to a behavioral change towards a less aggressive temperament, which potentially reduced the risk perceived by local human communities and thus limited persecution and attempts to eradicate the Apennine bear.…”

Counts of unique females with cubs in the Apennine brown bear population, 2006–2014

“…To estimate this probability we used the formula: where is the probability for an individual of age a and gender g to remain invisible to sampling until 2014. Sex specific capture probabilities in the 2004,2007,2008 and 2011 surveys were derived from Gervasi et al (2008Gervasi et al ( , 2010Gervasi et al ( , 2012 and Ciucci et al (2014), whereas and are yearly survival probabilities for cubs and adults, respectively (P. Ciucci unpublished data), assuming these remain constant across survey years. The complementary of (% corr ; Table S1) provides an estimate of the proportion of bears correctly classified as ≤4 years, suggesting that a great majority of bears with no previous hair-snag history are expected to be ≤4 years old.…”

Movement ecology of brown bears (Ursus arctos) in the Romanian Eastern Carpathians

“…The greater anthropogenic food availability at lower altitudes, such as orchards or crops, might also influence the brown bear distribution (Pop et al 2012), especially during the Hyperphagia season. Seasonal movements of brown bear in the Carpathians should be analysed in relation to seasonal changes in bear diet, approach often addressed in other studies (Stofik et al 2013, Ciucci et al 2014) to explain changes in brown bear movements.…”

“…Brown bears are opportunistic omnivores Selva 2012, Kavcic et al 2015) and their movements are heavily influenced by food resource availability (Nielsen et al 2006, Stofik et al 2013, Ciucci et al 2014, Kavcic et al 2015. In addition to food availability, other factors such as reproductive stage, den site availability or avoidance of conspecifics or predators, can affect the movement of individuals, which further poses challenges to understanding space use patterns (Nathan et al 2008).…”

“…To test the validity of using GMUs for brown bear management, we analyse the overlap between individual home ranges, core activity centers and the game management units. Lastly, we investigate the daily, seasonal and altitudinal movements of brown bears across four different seasons with varying food availability (Ciucci et al 2014, Roellig et al 2014). …”