Bulletin of Insectology 69 (1): 13-20, 2016 ISSN 1721-8861 A Mediterranean silvo-pastoral system supporting beehive health and productivity Ignazio FLORIS 1 , Simonetta BAGELLA 2 , Maria Carmela CARIA 2 , Luca RUIU 1 , Franco BUFFA 1 , Alberto SATTA 1 1 Dipartimento di Agraria, sezione di Patologia vegetale ed Entomologia, Università di Sassari, Italy 2 Dipartimento di Scienze della Natura e del Territorio, Università di Sassari, Italy Abstract The biological, productive and sanitary conditions were investigated in an experimental apiary in order to evaluate the aptitude of the Mediterranean silvo-pastoral systems to the maintenance and exploitation of bee colonies through the best hive management practices. Observations on bee colony dynamics, honey production in storing supers, Paenibacillus larvae (White 1906) spores detection and Varroa destructor Anderson et Trueman infestation were conducted. The annual trend of bee population dynamics showed two typical peaks (spring and autumn). The total average honey production was 70 kg per hive. From a sanitary point of view, colonies looked normal and healthy with the sole exception of V. destructor infestations that were regularly kept under the intervention threshold by hive management operations. The results suggest that the Mediterranean agro-silvo-pastoral systems may be particularly suitable for productive and healthy apiculture. Key words: honey production, honeybees, plant communities, pollen spectra, silvo-pastoral systems. Introduction In addition to their high value for worldwide honey and other beehive products, honey bees play a major role in plant biodiversity conservation in natural and semi- natural ecosystems and in modern agriculture productiv- ity through their essential pollination services (vanEngelsdorp et al., 2010). The growing concern for the enigmatic honey bee col- ony decline, experienced both in the United States and in Europe, is triggering extensive studies to identify the possible abiotic and biotic causal agents, including pathogens and parasites. It is well known that pest man- agement in agriculture frequently causes negative side effects on honey bees (Desneux et al., 2007; Maini et al., 2010). On the other side, bees are affected by the action of parasitic mites (Varroa destructor Anderson et True- man, Acarapis woodi Rennie, Tropilaelaps spp.), scav- engers (especially beetles) and various microbial patho- gens including bacteria [Paenibacillus larvae (White 1906), Melissococcus plutonius (ex White) Bailey et Collins corrig. Truper et de Clari], fungi [Nosema spp., Ascosphaera apis (Maasen ex Claussen) Olive et Spil- toir] and viruses (deformed wing virus, acute paralysis virus, black queen cell virus, sacbrood virus and others) (Higes et al., 2006; Nazzi et al., 2012; Gaggìa et al., 2015). Pesticides, particularly insecticides, may affect the honeybee immune system and increase their suscep- tibility to pathogens (Alaux et al., 2010a; Di Prisco et al., 2013; Doublet et al., 2015). Moreover, the increasing use of fertilizers and pesticides in agriculture, the pro- gress in destruction and fragmentation of natural and semi-natural habitats and the intensification of land use reduce the availability of suitable nesting sites, adequate forage and nourishment, thereby significantly affecting the fitness of honeybees and other pollinators (Rathcke and Jules, 1993; Quaranta et al., 2004; Tscharntke et al., 2005; Kremen et al., 2007). These negative factors can be mitigated by implementing agro-ecosystem manage- ment with integrated or organic farming, ensuring natu- ral and/or semi-natural habitat conservation and improv- ing farmland biodiversity (Steffan-Dewenter and West- phal, 2008; Decourtye et al., 2010). These conditions can be achieved in semi-natural ecosystems such as the Mediterranean agro-silvo-pastoral systems that provide different services to human societies (Millennium Eco- system Assessment, 2005). This typical Mediterranean system integrates forests, tree plantations and herbaceous crops with grazing livestock, thus ensuring a significant degree of diversification and combination of productive factors (Caballero et al., 2009). The typical environment of Mediterranean agro-silvo- pastoral systems is marked by two fundamental fea- tures: the Mediterranean character of the climate (dry summers and somewhat cold winters) and the low fertil- ity of the soil, making intensive farming unsustainable and unprofitable. In these systems, the most efficient strategy is diversification and the use of every natural resource with a minimum input of energy and materials (Olea and San Miguel-Ayanz, 2006). Moreover these systems can comply with societal needs such as land- scape and biodiversity conservation, or with ethical concerns on food production. Hence, these systems can easily adapt to market changes (Bernués et al., 2011) being particularly prone to a multiple use of the re- sources (Gómez Sal and González García, 2007). In this context, honey production represents a traditional re- source in harmony with agro-pastoral activities and eco- system conservation (Croitoru and Merlo, 2005). In the present work, the biological (colony develop- ment dynamics), productive (honey production and ma- jor pollen sources identification) and sanitary conditions (particularly American foulbrood and Varroosis), were investigated within a group of beehives in order to evaluate the aptitude of the Mediterranean silvo-pastoral systems in the maintenance and exploitation of bee colonies through the best hive management practices. The value of different vegetation types for honey pro- duction in the same site and period were reported earlier (Bagella et al., 2013b).