Avoidance of different durations, colours and intensities of artificial light by adult seabirds

There is increasing evidence for impacts of light pollution on the physiology and behaviour of wild animals. Nocturnally active Procellariiform seabirds are often found grounded in areas polluted by light and struggle to take to the air again without human intervention. Hence, understanding their responses to diferent wavelengths and intensities of light is urgently needed to inform mitigation measures. Here, we demonstrate how diferent light characteristics can afect the nocturnal fight of Manx shearwaters Pufnus pufnus by experimentally introducing lights at a colony subject to low levels of light pollution due to passing ships and coastal developments. The density of birds in fight above the colony was measured using a thermal imaging camera. We compared number of fying shearwaters under dark conditions and in response to an artifcially introduced light, and observed fewer birds in fight during ‘light-on’ periods, suggesting that adult shearwaters were repelled by the light. This efect was stronger with higher light intensity, increasing duration of ‘light-on’ periods and with green and blue compared to red light. Thus, we recommend lower light intensity, red colour, and shorter duration of ‘light-on’ periods as mitigation measures to reduce the efects of light at breeding colonies and in their vicinity

The effect of light pollution on orientation in Manx shearwaters (Puffinus puffinus)

Humans introduce artificial light at night (ALAN) to the landscape for many reasons - to facilitate commuting to work, to improve their safety and to enhance the nocturnal aesthetics of places. The resulting change in light levels distorts a cue which living organisms use. A cue which, otherwise, has been predictable for billions of years. While some animals adjust to or even take advantage of ALAN, other species respond negatively, with populations suffering due to the presence of artificial light. In particular, burrow-nesting seabirds struggle with light pollution located near to their colony, with thousands of juvenile birds landing in lit-up areas during fledging season – termed ‘grounding’. The aim of this thesis is to investigate the behaviour of seabirds towards light pollution and, ultimately, to understand mechanistically the processes involved in grounding of seabirds. I explore, through observation and experimentation, the behavioural responses of an ALAN-susceptible seabird, the Manx shearwater (Puffinus puffinus) to artificial light. These experiments span the life-history stages of the Manx shearwater, from the orientation of juvenile shearwaters, before and during fledging, to the responses of breeding adults at the colony. I discover that the magnitude, but not direction, of behavioural reactions to artificial light is consistent across these life stages. At each life stage, reactions to ALAN appear to be related to the intensity and wavelength of light, the latter of which implies disruption of the visual system as a root cause of seabird grounding. Finally, in an applied study, I explore the effectiveness that updating old sodium pressure lamps with LEDs has had on shearwater grounding in a coastal town. Overall this thesis highlights the importance of understating the animals’ behaviour towards light pollution at different life stages and locations, contributing to the evidence base for mitigation measures that might be implemented in future.</p

Criteria and directions of quarries adaptations in surroundings of the Cracow

Wydobycie surowców skalnych związane jest z ingerencją w środowisko i przekształceniem jego komponentów. Wielowiekowa ingerencja w środowisko otaczające złoża surowców skalnych doprowadziła do powstania nieużytków poeksploatacyjnych, zajmujących znaczną powierzchnię. W dobie nasilającej się urbanizacji i industrializacji oraz stałego zmniejszania obszarów nie przekształconych działalnością człowieka zwrócono uwagę na możliwość ich odzyskania dzięki różnokierunkowej adaptacji. Pozwala ona nadać im nowe funkcje użytkowe poprzez wykorzystanie potencjału istniejących w nich zasobów naturalnych i antropogenicznych.Mining influences natural environment and causes transformation of its components. Centuries of interference in environment surrounding mineral deposits has driven to forming post-mining sites, which occupy large areas. In time of growing urbanization, industrialization and permanently diminishing number of areas not changed by human activity attention is paid to the possibility of regaining these areas by adaptation in various directions. It allows to introduce new useful functions by using the potential of existing natural and anthropogenic resources

Shearwaters sometimes take long homing detours when denied natural outward journey information

The cognitive processes (learning and processing of information) underpinning long-distance navigation of birds are poorly understood. Here, we utilised the homing motivation of the Manx shearwater to investigate navigational decision making in a wild bird by displacing them 294km to the far side of a large island (the Island of Ireland). Since shearwaters are reluctant to fly over land, the island blocked the direct route home, forcing a navigational decision. Further still, on the far side of the obstacle, we chose a release site where use of local knowledge could facilitate a 20% improvement in route efficiency if shearwaters were able to anticipate and avoid a large inlet giving the appearance of open water in the home direction. We found that no shearwater took the most efficient initial route home, but instead oriented in the home direction (even once the obstacle became visible). Upon reaching the obstacle, four shearwaters subsequently circumnavigated the land mass via the long route, travelling a further 900km as a result. Hence, despite readily orienting homewards immediately after displacement, shearwaters seem unaware of the scale of the obstacle formed by a large land mass despite this being a prominent feature of their regular foraging environment

An assay to investigate factors influencing initial orientation in nocturnally fledging seabirds

The first solitary migration of juvenile birds is difficult to study because of a low juvenile survival rates and sometimes long delays in return to the breeding grounds. Consequently, little is known about this crucial life event for many bird species, in particular the sensory guidance mechanisms facilitating the first migratory journey. Initial orientation during the first migration is a key measure to investigate these mechanisms. Here, we developed an assay to measure initial orientation as flight direction upon first take‐off in nocturnally fledging juvenile seabirds. We dorsally deployed a coloured LED on juvenile birds to allow researchers to observe the vanishing bearings of individuals as they flew out to sea. Additionally, we co‐deployed either a small Neodymium magnet or glass bead (control) on top of the bird's head to investigate the use of magnetoreception, previously unexplored in this early life stage. We used this assay to observe the first flight of Manx shearwaters (Puffinus puffinus) and found that they did not orient towards their wintering ground straight after taking off. Further, we did not find an effect of the magnetic treatment on juveniles’ flight direction, though whether this is due to the birds not using magnetoreception, other salient cues being available or a lack of motivation to orient to the migratory beeline is unclear. We were, however, able to identify wind direction and topography as drivers of first flight direction in Manx shearwaters, which fledged with wind component between a crosswind and a tailwind and directed their maiden flight towards the sea and away from the land. This novel assay will facilitate the study of the maiden flight of nocturnally fledging birds and will help advance the study of sensory guidance mechanisms underpinning migratory orientation in a wide range of taxa, including species which are traditionally challenging to study.</p

Avoidance of different durations, colours and intensities of artificial light by adult seabirds

There is increasing evidence for impacts of light pollution on the physiology and behaviour of wild animals. Nocturnally active Procellariiform seabirds are often found grounded in areas polluted by light and struggle to take to the air again without human intervention. Hence, understanding their responses to different wavelengths and intensities of light is urgently needed to inform mitigation measures. Here, we demonstrate how different light characteristics can affect the nocturnal flight of Manx shearwaters Puffinus puffinus by experimentally introducing lights at a colony subject to low levels of light pollution due to passing ships and coastal developments. The density of birds in flight above the colony was measured using a thermal imaging camera. We compared number of flying shearwaters under dark conditions and in response to an artificially introduced light, and observed fewer birds in flight during ‘light-on’ periods, suggesting that adult shearwaters were repelled by the light. This effect was stronger with higher light intensity, increasing duration of ‘light-on’ periods and with green and blue compared to red light. Thus, we recommend lower light intensity, red colour, and shorter duration of ‘light-on’ periods as mitigation measures to reduce the effects of light at breeding colonies and in their vicinity

Optimization of dynamic soaring in a flap-gliding seabird impacts its large-scale distribution at sea

Dynamic soaring harvests energy from a spatiotemporal wind gradient, allowing albatrosses to glide over vast distances. However, its use is challenging to demonstrate empirically, and has yet to be confirmed in other seabirds. Here we investigate how flap-gliding Manx Shearwaters optimize their flight for dynamic soaring. We do so by deriving a new metric, the horizontal wind effectiveness, that quantifies how effectively flight harvests energy from a shear layer. We evaluate this metric empirically for fine-scale trajectories reconstructed from bird-borne video data using a simplified flight dynamics model. We find that the birds’ undulations are phased with their horizontal turning to optimize energy harvesting. We also assess the opportunity for energy harvesting in long-range, GPS-logged foraging trajectories, and find that Manx Shearwaters optimize their flight to increase the opportunity for dynamic soaring during favourable wind conditions. Our results show how smallscale dynamic soaring impacts large-scale Manx Shearwater distribution at sea

Short-term behavioural impact contrasts with long-term fitness consequences of biologging in a long-lived seabird

Biologging has emerged as one of the most powerful and widely used technologies in ethology and ecology, providing unprecedented insight into animal behaviour. However, attaching loggers to animals may alter their behaviour, leading to the collection of data that fails to represent natural activity accurately. This is of particular concern in free-ranging animals, where tagged individuals can rarely be monitored directly. One of the most commonly reported measures of impact is breeding success, but this ignores potential short-term alterations to individual behaviour. When collecting ecological or behavioural data, such changes can have important consequences for the inference of results. Here, we take a multifaceted approach to investigate whether tagging leads to short-term behavioural changes, and whether these are later reflected in breeding performance, in a pelagic seabird. We analyse a long-term dataset of tracking data from Manx shearwaters (Puffinus puffinus), comparing the effects of carrying no device, small geolocator (GLS) devices (0.6% body mass), large Global Positioning System (GPS) devices (4.2% body mass) and a combination of the two (4.8% body mass). Despite exhibiting normal breeding success in both the year of tagging and the following year, incubating birds carrying GPS devices altered their foraging behaviour compared to untagged birds. During their foraging trips, GPS-tagged birds doubled their time away from the nest, experienced reduced foraging gains (64% reduction in mass gained per day) and reduced flight time by 14%. These findings demonstrate that the perceived impacts of device deployment depends on the scale over which they are sought: long-term measures, such as breeding success, can obscure finer-scale behavioural change, potentially limiting the validity of using GPS to infer at-sea behaviour when answering behavioural or ecological questions

Supplementary Data accompanying: "Optimization of dynamic soaring in a flap-gliding seabird impacts its large-scale distribution at sea"

This archive contains the data associated with the paper “Optimization of dynamic soaring in a flap-gliding seabird impacts its large-scale distribution at sea”. It contains: (i) a zipped folder (OnboardVideos.zip) containing the raw video data of n=9 flight trajectories flown by 6 individual Manx Shearwaters on 6 different days; (ii) the horizon end point coordinates output by the semi-automatic horizon detection algorithm, and the parameters needed to process these coordinates (dataAndProcessingParameters.mat) to generate the data set on which the analyses presented in the Results section can be conducted in Matlab; (iii) the processed video data needed to conduct the analyses presented in the Results section (processedVideoData.csv); and (iv) the processed GPS and wind data from n=349 two-leg trajectories, and n=38 one-leg trajectories, needed to conduct the analyses presented in the Results section (trackSummaries2016To2019.csv); (v) a zipped folder (GPSTracks.zip) containing the corresponding GPS tracks and associated wind data as individual CSV files; (vi) a README file giving further details on content