Factors Influencing Cage Escape Behavior in a Migrating Passerine at a Stop-Over Site.

Cognitive abilities play a critical role for migratory birds encountering unfamiliar habitats at stop-over sites. We investigated factors (age, sex, fuel reserves, vertical/horizontal activity, and mercury level) affecting cognitive abilities behavior (problem-solving task-escaping from an experimental cage) in a long-distance migratory passerine, the sedge warbler () at an autumn stop-over site. During the experiment, after two minutes of acclimatization, we remotely opened the door of the cage and recorded whether each bird escaped or remained in the cage.

Nesting niche partitioning between two sympatrically breeding Chlidonias Tern species revealed by remote sensing.

Sympatrically breeding avian species may have similar environmental requirements for nesting sites, resulting in interspecific competition. It may be reduced by partitioning resources in space or/and time, allowing relatively stable coexistence in the shared habitat. Here, we investigated nesting niches of sympatrically breeding, Black Terns (BT, Chlidonias niger) and Whiskered Terns (WT, Chlidonias hybrida) in Druzno Lake (Poland) in 2024.

Host-related genetic differentiation of a polyxenic avian ectoparasite, (Hippoboscidae).

Ectoparasites play a key role in ecosystems, affecting the health, behaviour, and reproductive success of their hosts. The parasite-host relationships are complex and dynamic, and selective pressures exerted by the hosts can lead to local adaptations and changes in the genetic structure of the parasite population. Our aim was to investigate how parasitism on a diverse range of avian hosts with varying ecology and habitat preferences shapes the genetic variation of the parasite.

Impact of highly pathogenic avian influenza virus (HPAIV) on Black-headed Gulls population in Poland in 2023.

The highly pathogenic avian influenza virus (HPAIV) A(H5N1) has caused the most extensive and severe epizootic event affecting both poultry and wild birds globally. This study investigated the impact of HPAIV on the breeding population of the Black-headed Gull , the most abundant gull species in Poland. During the 2023 outbreak, this species was reported as the most frequently infected in the country.

Influence of local (air temperature) and wide-scale (North Atlantic Oscillation) climate indices on the first arrival dates of the Common Wood Pigeon (Columba palumbus) at breeding site in SE Poland.

In this study, a relationship between climate indices (local - air temperatures, and wide-scale - North Atlantic Oscillation) and first arrival dates (FAD) of a short-distant migratory bird, the Common Wood Pigeon (Columba palumbus) at a breeding site in SE Poland (Lublin) was investigated. Temporal patterns of FAD on a multi-year scale (20 years within 39 years between 1982 and 2020) were also studied. Additionally, correlations between mean air temperature at Lublin and sites along the spring migration route with various distances from the breeding site and various time lags were searched for.

Foraging Habitat Availability and the Non-Fish Diet Composition of the Grey Heron () at Two Spatial Scales.

Habitat structure on foraging ground is one of the crucial factors determining diet diversity in colonially breeding avian predators. Quantifying the habitat and diet composition at different spatial scales (regional and local inter-colonial) can help provide understanding of the drivers of diet composition. In this study, we examined the composition of the non-fish diet of an opportunistic predator, the Grey Heron (), based on pellets.

Decline in the West Greenland population of a zooplanktivorous seabird, the little auk Alle alle.

The warming of the Arctic had lead to a diverse range of impacts on local biota, including northward shifts of some species range. Here, we report past and present distribution and abundance of an Arctic zooplanktivorous seabird, the little auk Alle alle in West Greenland south of 74° N, and examine the changes in sea surface temperature (SST) and sea ice concentration (SIC) in the birds foraging areas in 1850-2007. We estimated the little auk population in the studied region to be 5,200 pairs in the 1930s, 6,000-6,500 pairs in the 1940-1970s and 70-80 pairs by the 2000s.

Diversity of major histocompatibility complex of II B gene and mate choice in a monogamous and long-lived seabird, the Little Auk (Alle alle).

The major histocompatibility complex (MHC) plays a key role in the adaptive immune system of vertebrates, and is known to influence mate choice in many species. In birds, the MHC has been extensively examined but mainly in galliforms and passerines while other taxa that represent specific ecological and evolutionary life-histories, like seabirds, are underexamined. Here, we characterized diversity of MHC Class II B exon 2 in a colonial pelagic seabird, the Little Auk (or Dovekie Alle alle).

Exploring avian exposure to parent polycyclic aromatic hydrocarbons (PAHs): Using the common eider Somateria mollissima in a global context.

Compared to other organic contaminants, birds are rarely studied for their exposure to polycyclic aromatic hydrocarbons (PAHs), mainly due to their effective metabolization of parent PAHs. However, as some studies suggest, exposure to PAHs may result in adverse health effects including decreased survival, especially following oil spills. In the present study, we analyzed samples from a sea duck, the common eider Somateria mollissima including feathers, preen oil, blood, liver and bile, to evaluate whether non- lethally collected samples could be reliably used for avian biomonitoring strategies.

Concentration of metals and metalloids in livers of birds of various foraging guilds collected during the autumn migration period in Poland.

During migration, birds explore various habitats at stopover sites that differ in food resources and contamination levels. In this study, hepatic concentrations of 21 elements (metals and metalloids) in 11 species of birds, representing various foraging habitats (such as aquatic, aquatic/terrestrial, and terrestrial) and migration modes (migratory and sedentary) representing various foraging guilds (omnivores, piscivores, and molluscivores), were analyzed. The samples (N = 84) were collected during the autumn migration period in Poland.

Molecular tools prove little auks from Svalbard are extremely selective for Calanus glacialis even when exposed to Atlantification.

Two Calanus species, C. glacialis and C. finmarchicus, due to different life strategies and environmental preferences act as an ecological indicators of Arctic Atlantification.

Experimental reduction in blood oxygen-carrying capacity alters foraging behaviour in a colonial waterbird.

Oxidative metabolism is a key component of organismal physiology and it is primarily determined by aerobic capacity, which depends on the capacity of blood to carry oxygen. However, experimental manipulations of blood oxygen-carrying capacity are rarely implemented to test ecophysiological hypotheses in vertebrate populations. Here, we combined an experimental manipulation of blood oxygen-carrying capacity with GPS tracking to test whether suboptimal (reduced) haematological performance affects foraging behaviour in a colonial waterbird, the black-headed gull, Chroicocephalus ridibundus.

A keystone avian predator faces elevated energy expenditure in a warming Arctic.

Climate change is transforming bioenergetic landscapes, challenging behavioral and physiological coping mechanisms. A critical question involves whether animals can adjust behavioral patterns and energy expenditure to stabilize fitness given reconfiguration of resource bases, or whether limits to plasticity ultimately compromise energy balance. In the Arctic, rapidly warming temperatures are transforming food webs, making Arctic organisms strong models for understanding biological implications of climate change-related environmental variability.

Post-foraging in-colony behaviour of a central-place foraging seabird.

Studies on time allocation of various activities are crucial to understand which behavioural strategy is the most profitable in a given context, and so why animals behave in a particular way. Such investigations usually focus on a time window when the studied activity is performed, often neglecting how the time devoted to focal activity affects time allocation to following-up behaviours, while that may have its own fitness consequences. In this study, we examined time allocation into three post-foraging activities (entering the nest with food, nest attendance, and colony attendance) in a small seabird species, the little auk (Alle alle).

Mercury contamination and potential health risks to Arctic seabirds and shorebirds.

Since the last Arctic Monitoring and Assessment Programme (AMAP) effort to review biological effects of mercury (Hg) on Arctic biota in 2011 and 2018, there has been a considerable number of new Arctic bird studies. This review article provides contemporary Hg exposure and potential health risk for 36 Arctic seabird and shorebird species, representing a larger portion of the Arctic than during previous AMAP assessments now also including parts of the Russian Arctic. To assess risk to birds, we used Hg toxicity benchmarks established for blood and converted to egg, liver, and feather tissues.

Identification of Factors Affecting Environmental Contamination Represented by Post-Hatching Eggshells of a Common Colonial Waterbird with Usage of Artificial Neural Networks.

Artificial Neural Networks are used to find the influence of habitat types on the quality of the environment expressed by the concentrations of toxic and harmful elements in avian tissue. The main habitat types were described according to the Corine Land Cover CLC2012 model. Eggs of free-living species of a colonial waterbird, the grey heron were used as a biological data storing media for biomonitoring.

Eye Region Surface Temperature and Corticosterone Response to Acute Stress in a High-Arctic Seabird, the Little Auk.

Measuring changes in surface body temperature (specifically in eye-region) in vertebrates using infrared thermography is increasingly applied for detection of the stress reaction. Here we investigated the relationship between the eye-region temperature (TEYE; measured with infrared thermography), the corticosterone level in blood (CORT; stress indicator in birds), and some covariates (ambient temperature, humidity, and sex/body size) in a High-Arctic seabird, the Little Auk . The birds responded to the capture-restrain protocol (blood sampling at the moment of capturing, and after 30 min of restrain) by a significant TEYE and CORT increase.

A quiet extirpation of the breeding little auk Alle alle population in Iceland in the shadow of the famous cousin extermination.

The little auk Alle alle is an Arctic seabird breeding in the North Atlantic. Its southernmost breeding population in the Low Arctic occurred in Iceland but started to decline in numbers at the beginning of the 20th century ending in extirpation at the end of the same century. Climate warming has been blamed for the disappearance of this population.