feeding ecology of the scops owl otus scops aves strigiformes in the island of pianosa tuscan archipelago central italy outside the breeding period

ABSTRACTAll of the published studies but one about the diet of the Eurasian scops owl Otus scops, a nocturnal raptor of conservation concern, were carried out during the breeding period, just before or immediately after the chicks fledged. The species is a trans-Saharian migrant with few resident populations in Europe. Orthoptera make up the staple of its diet in summer. In this study, we investigated the diet of scops owls on the island of Pianosa after the breeding period through the analysis of pellets. A total of 327 fragments belonging to at least 14 taxa were identified from 56 pellets collected after the breeding period, between late August and March. By frequency, invertebrates constituted 80.00% of the diet, with Coleoptera being the most represented order (62.35% of the total diet) and Orthoptera poorly represented (8.24%). Vertebrates included two bird species, three small mammals and the Moorish gecko. Although the meal-to-pellet interval for scops owls is unknown, we suggest that the bank vol..

Biology and Prevalence in Northern Italy ofVerrallia aucta(Diptera, Pipunculidae), a Parasitoid ofPhilaenus spumarius(Hemiptera, Aphrophoridae), the Main Vector ofXylella fastidiosain Europe

Simple Summary The meadow spittlebug,Philaenus spumariusis the major vector ofXylella fastidiosain Europe. The spread ofX. fastidiosadepends almost exclusively on insect transmission, and therefore, it is vital to keep vector populations low. To achieve this goal, natural enemies should be identified and their efficacy evaluated. The aim of this work was to assess the presence and abundance of a parasitoid fly,Verrallia aucta, in field-collected spittlebugs. At first, we developed a new species-specific molecular tool (PCR) to identify the parasitoid, then we estimated the parasitization rate in different sites of northern Italy using both PCR and the dissection of insect bodies. Finally, we established a small-scale rearing to describe the life cycle of the fly on its spittlebug host.Verrallia auctais quite common in northern Italy but displayed low prevalence, reaching a maximum parasitization rate of 17.5% in vineyards of the Piemonte region. The fly has one generation per year, lays eggs in newly emerged adults of spittlebugs, and develops inside the host throughout the summer. The mature larva abandons the dead victim at the beginning of autumn and pupates in the soil where it overwinters. The meadow spittlebug,Philaenus spumarius(L.) (Hemiptera Aphrophoridae), the main vector ofXylella fastidiosaWells et al. in Europe, has few known natural enemies. The endoparasitoidVerrallia aucta(Fallen) (Diptera, Pipunculidae) was first noticed a long time ago but very little is known about its biology and prevalence. In this study, the presence and prevalence ofV. auctawere investigated in different regions of northern Italy, both in plain-foothill and montane zones. Parasitic larvae were identified by the dissection of spittlebug adults,P. spumariusandNeophilaenus campestris(Fallen), and by a new species-specific molecular tool targeting theITS2andCOIgenomic regions, developed in this work. A small-scale rearing was set up to gain information on the life cycle ofV. auctaon its main hostP. spumarius. During the four-year investigation (2016-2019) the pipunculid parasitoid displayed low prevalence, reaching a maximum parasitization rate of 17.5% (calculated over the adult spittlebug season) in vineyards of the Piemonte region. Over the whole period, no significant difference in the prevalence was found between male and female spittlebugs. Collected data and rearing observations suggest thatV. auctais monovoltine and synchronous withP. spumarius, laying eggs in newly emerged adults, developing as an endoparasitoid through two larval stages during the whole summer, and overwintering as a pupa in the soil

Predatory efficacy of Dicyphus errans on different prey

The Palaearctic predator Dicyphus errans (Hemiptera: Miridae) lives omnivorously on various host plants, preying on a wide range of small arthropods, including some new invasive alien species. These characteristics make it a promising biological control agent (BCA) in organic greenhouses. The capacity of a BCA to find, kill and consume prey plays a fundamental role in trophic interactions and population dynamics in a predator-prey system. The functional response of a predator, which describes how the individual rate of prey consumption changes in response to prey density, is a key component to assess its effectiveness in pest control and the stability of its own populations. Therefore, the functional response of D. errans on different prey was studied to improve our knowledge on the potential of this mirid, which is naturally widespread in European organic greenhouses. Laboratory experiments were carried out on three exotic pests: the poinsettia thrips Echinothrips americanus (Thysanoptera: Thripidae), the greenhouse whitefly Trialeurodes vaporariorum (Hemiptera: Aleyrodidae), and the tomato borer Tuta absoluta (Lepidoptera: Gelechiidae), to build functional response curves. Prey was offered at different densities to single females of D. errans for 24 h. The predation behaviour of D. errans on all the prey species was defined by Type II functional response curves. The female could daily prey about 62 adults of E. americanus, 114 pupae of T. vaporariorum, and 236 eggs of T. absoluta. The high voracity of this generalist predator on different prey confirmed its suitability as a BCA. For effective and stable pest control strategies, a prior to pest establishment of D. errans in organic greenhouses may prevent pest escaping in case of high infestation rates, even if the type II functional response reaches saturation at very high prey densities

The potential of host plants for biological control of Tuta absoluta by the predator Dicyphus errans

AbstractDicyphus errans (Wolff) has been shown to be a suitable biocontrol agent for Tuta absoluta (Meyrick). This generalist predator shares various host plants with the exotic pest, and these interactions could be exploited to enhance pest control. Therefore, host preference, survival rate and development times of the predator and prey were investigated on crop and non-crop plant species. Among the tested plants, the favourite hosts were Solanum species for T. absoluta, and herb Robert, European black nightshade, courgette and tomato for D. errans. Tuta absoluta accepted the same plant species as hosts for oviposition, but it never developed on herb Robert and courgette in all the experiments. Based on our results, we would suggest the use of courgette and herb Robert in consociation with tomato and as a companion plant, respectively, which may keep pest densities below the economic threshold. Moreover, the omnivorous and widespread D. errans could be a key predator of this exotic pest, allowing a high encounter probability on several cultivated and non-cultivated plant species.</jats:p