Search results for " ornithology"
showing 10 items of 72 documents
Variation in timing of breeding of five woodpeckers in a primeval forest over 45 years: role of food, weather, and climate
2020
AbstractClimate warming could lead to ‘mis-matching’ of birds’ breeding times with availability of their invertebrate food resources. Fluctuating spring temperatures could influence variation in the commencement of egg-laying, as well as, in phenology of their resources (e.g., tree bud burst, appearance of folivorous caterpillars). We studied timing of Dendrocopos leucotos, Dendrocoptes medius, Dendrocopos major, Dryobates minor, and Picoides tridactylus breeding in, free of direct human intervention, strictly protected fragments of Białowieża Forest (Poland) in 1975–2019. We related their onset of breeding to inter-year variation in spring weather, trees’ bud burst and timing of folivorous…
Wind effects on the migration routes of trans-Saharan soaring raptors: geographical, seasonal, and interspecific variation
2016
Wind is among the most important environmental factors shaping birds’ migration patterns. Birds must deal with the displacement caused by crosswinds and their behavior can vary according to different factors such as flight mode, migratory season, experience, and distance to goal areas. Here we analyze the relationship between wind and migratory movements of three raptor species which migrate by soaring–gliding flight: Egyptian vulture Neophron percnopterus, booted eagle Aquila pennata, and short-toed snake eagle Circaetus gallicus. We analyzed daily migratory segments (i.e., the path joining consecutive roosting locations) using data recorded by GPS satellite telemetry. Daily movements of E…
Barrier crossings and winds shape daily travel schedules and speeds of a flight generalist
2021
External factors such as geography and weather strongly affect bird migration influencing daily travel schedules and flight speeds. For strictly thermal-soaring migrants, weather explains most seasonal and regional differences in speed. Flight generalists, which alternate between soaring and flapping flight, are expected to be less dependent on weather, and daily travel schedules are likely to be strongly influenced by geography and internal factors such as sex. We GPS-tracked the migration of 70 lesser kestrels (Falco naumanni) to estimate the relative importance of external factors (wind, geography), internal factors (sex) and season, and the extent to which they explain variation in trav…
From mammals back to birds: Host-switch of the acanthocephalan Corynosoma australe from pinnipeds to the Magellanic penguin Spheniscus magellanicus.
2017
Trophically-transmitted parasites are regularly exposed to potential new hosts through food web interactions. Successful colonization, or switching, to novel hosts, occur readily when ?donor? and ?target? hosts are phylogenetically related, whereas switching between distantly related hosts is rare and may result from stochastic factors (i.e. rare favourable mutations). This study investigates a host-switching event between a marine acanthocephalan specific to pinnipeds that is apparently able to reproduce in Magellanic penguins Spheniscus magellanicus from Brazil. Detailed analysis of morphological and morphometrical data from acanthocephalans from penguins indicates that they belong to Cor…
Benefits of the European Agri-Environment Schemes for Wintering Lapwings : A Case Study from Rice Fields in the Mediterranean Region
2020
Mediterranean European rice fields provide important habitats for migrating waterbirds. In winter. one waterbird species that particularly benefits from rice fields is the Northern Lapwing (VaneIlus vanellas), a species threatened in Europe. To assess the effect of agii-environmental measures on rice field selection and use by wintering lapwings, bird counts were conducted in northeastern Spain during two consecutive winters (2005-2006 and 2006-2007). Information on two mandatory post-harvest management prescriptions of the agri-environment schemes was collected, namely winter flooding (percent ground surface covered by water) and whether fields were rolled or not. The number of lapwings in…
Using genetic markers to unravel the origin of birds converging towards pre-migratory sites
2018
AbstractIdentifying patterns of individual movements in spatial and temporal scales can provide valuable insight into the structure of populations and the dynamics of communities and ecosystems. Especially for migrating birds, that can face a variety of unfavorable conditions along their journey, resolving movements of individuals across their annual cycle is necessary in order to design better targeted conservation strategies. Here, we studied the movements of a small migratory falcon, the Lesser Kestrel (Falco naumanni), by genetically assigning feathers from individuals of unknown origin that concentrate in large roosts during the pre-migratory period. Our findings suggest that birds fro…
A Successful Crowdsourcing Approach for Bird Sound Classification
2023
Automated recorders are increasingly used in remote sensing of wildlife, yet automated methods of processing the audio remains challenging. Identifying animal sounds with machine learning provides a solution, but optimizing the models requires annotated training data. Producing such data can require much manual effort, which could be alleviated by engaging masses to contribute to research and share the workload. Birdwatchers are experts on identifying bird vocalizations and form an ideal focal audience for a citizen science project aiming for the required multitudes of annotated avian audio data. For this purpose, we launched a web portal that was targeted and advertised to Finnish birdwatc…
The design of artificial nestboxes for the study of secondary hole-nesting birds: A review of methodological inconsistencies and potential biases
2010
The widespread use of artificial nestboxes has led to significant advances in our knowledge of the ecology, behaviour and physiology of cavity nesting birds, especially small passerines. Nestboxes have made it easier to perform routine monitoring and experimental manipulation of eggs or nestlings, and also repeatedly to capture, identify and manipulate the parents. However, when comparing results across study sites the use of nestboxes may also introduce a potentially significant confounding variable in the form of differences in nestbox design amongst studies, such as their physical dimensions, placement height, and the way in which they are constructed and maintained. However, the use of …
Editorial: Mind the (gender) gap: Prospects and strategies for women's career in ornithology
2021
On a small island, someone is patiently looking at the ocean, waiting for the shearwaters to come back to their nests, the hair blown by a gentle breeze, a laptop full of notes open on the legs. On the other side of the globe, perched on a high ladder, a scientist is checking a Pygmy Owl nest box. A cautious song breaks the stillness of the morning: spring is coming and soon the taiga will be alive with breeding activities. In a small lab, under a buzzing lamp, a young researcher is hunched over a pile of ancient bird bones. Each one echoes past stories of changing climate, warning us about the future. A lonely figure stands against a hazy sky, meditating on the battles won and those still …
Alcione e l'alcione. Archeologia del mito: nuclei tematici, funzioni simboliche, storia di contaminazioni
2021
Lo studio prende in considerazione le più antiche testimonianze della letteratura greca riguardanti il mito di Alcione e dell’uccello omonimo, per tentare di enuclearne funzione culturale e nuclei tematici originari. Rientrano nel quadro dell’analisi considerazioni sulla figura di Cleopatra Alcione in Hom. Il. 9, 561, sulle stratificazioni del mito post-omeriche con particolare riguardo per la tradizione esiodea del mito, con un’analisi del fr. 26 Davies di Alcmane (cerili e alcioni) nonché del fr. 508 Page di Simonide, quest’ultimo valutato rispetto agli aspetti ornitologici del mito (i giorni alcionii). Chiude l’indagine una proposta di interpretazione etimologica del nome Alcione (connes…