Search results for "Nesting"
showing 7 items of 87 documents
Breeding near heterospecifics as a defence against brood parasites: can redstarts lower probability of cuckoo parasitism using neighbours?
2022
Breeding habitat choice based on the attraction to other species can provide valuable social information and protection benefits. In birds, species with overlapping resources can be a cue of good quality habitats; species with shared predators and/or brood parasites can increase joint vigilance or cooperative mobbing, while raptors may provide a protective umbrella against these threats. We tested whether the migratory common redstart (Phoenicurus phoenicurus) is attracted to breed near active nests of the great tit (Parus major), a keystone-information source for migrant passerine birds, or a top predator, the northern goshawk (Accipiter gentilis). This system is unique to test these quest…
CO2 effects on behaviour and reproduction of nesting fish species
2014
Ocean acidification is a global phenomenon linked to the CO2 absorption by the surface of the sea. This increasing process leads to a rise of the CO2 partial pressure (pCO2) that changes the seawater chemistry. It is known that such changes have negative consequences for many marine organisms. However, the effects of acidification on fishes are yet poorly understood. Fishes have been hypothesized to be more physiologically tolerant to elevated CO2. Nevertheless, many researches have described severe effects of altered pCO2 levels on fish behaviour, especially during early life history stages, and only few authors have focused on fish reproduction. The aim of my Ph.D. research is to investig…
Aggiornamento sulla nidificazione della Tartaruga marina Caretta caretta (Reptilia Cheloniidae) in Sicilia. Riflessioni sul valore della Citizen Scie…
2020
Updating of egg-laying of Loggerhead sea Turtle Caretta caretta (Reptilia Chelonidae) in Sicily. Remarks on the value of the Citizen Science. The aim of this paper is to put together data on the egg- laying by the Loggerhead sea Turtle Caretta caretta in Sicily, mainly after recordings by amateurs, tourists and occasional observers. 25 nesting events by this turtle are reported in the main island in 2017 and 2018. Comparing these figures with past records, they appear very high; it may be in part due to an awareness campaign carried out in the last years to solicit such reports. This suggests that Sicily may host a much higher nesting population of the Loggerhead sea Turtle than previously …
Nesting Problems : Exact and Heuristic Algorithms
2013
Nesting problems are two-dimensional cutting and packing problems involving irregular shapes. This thesis is focused on real applications on Nesting problems such as the garment industry or the glass cutting. The aim is to study different mathematical methodologies to obtain good lower bounds by exact procedures and upper bounds by heuristic algorithms. The core of the thesis is a mathematical model, a Mixed Integer Programming model, which is adapted in each one of the parts of the thesis. This study has three main parts: first, an exact algorithm for Nesting problems when rotation for the pieces is not allowed; second, an Iterated Greedy algorithm to deal with more complex Nesting problem…
Reed Warbler Hosts Do Not Fine-Tune Mobbing Defenses During the Breeding Season, Even When Cuckoos Are Rare
2021
Hosts of brood parasitic cuckoos often employ mobbing attacks to defend their nests and, when mobbing is costly, hosts are predicted to adjust their mobbing to match parasitism risk. While evidence exists for fine-tuned plasticity, it remains unclear why mobbing does not track larger seasonal changes in parasitism risk. Here we test a possible explanation from parental investment theory: parents should defend their current brood more intensively as the opportunity to replace it declines (re-nesting potential), and therefore “counteract” any apparent seasonal decline to match parasitism risk. We take advantage of mobbing experiments conducted at two sites where reed warblers (Acrocephalus sc…
Invasive Northern red oaks benefit temnothorax crassispinus (Hymenoptera: Formicidae) ant colonies
2018
Non-native plant species can modify their environment, and their influence on food chains is well recognized. How ever, the phenomenon of non-nutrient dependent interaction between non-native plants and native animals has received little attention to date. The Northern Red Oak (Quercus rubra) is a non-native, invasive tree species in Europe, which strongly negatively influences co-occurring plants. However, a part of the native fauna is able to utilize the resources offered by this species in its non-native range. We studied a common species of wood ant, Temnothorax crassispinus, in forests under canopies of non-native Northern Red Oak and native oaks, Pedunculate Oak (Q. robur), and Sessil…
Interspecific information on predation risk affects nest site choice in a passerine bird
2018
Abstract Background Breeding site choice constitutes an important part of the species niche. Nest predation affects breeding site choice, and has been suggested to drive niche segregation and local coexistence of species. Interspecific social information use may, in turn, result in copying or rejection of heterospecific niche characteristics and thus affect realized niche overlap between species. We tested experimentally whether a migratory bird, the pied flycatcher Ficedula hypoleuca, collects information about nest predation risk from indirect cues of predators visiting nests of heterospecific birds. Furthermore, we investigated whether the migratory birds can associate such information w…