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Energetic constraint during reproduction may limit the number or quality of young that a parent can produce per breeding attempt or the parent's longevity or future productivity, ultimately constraining lifetime reproductive success. The Eurasian dotterel Charadrius morinellus experienced energetic constraint during the Incubation period. Dotterel breed in the cold arctic-alpine zone and most breeding attempts are cared for by the male alone. The combination of a cold climate, giving high energetic costs of incubation and thermoregulation, and restricted foraging time due to uniparental Incubation, resulted in non-adaptive mass loss and constrained Investment of time and energy In incubation. If the incubation period is potentially energetically constrained, then behavioural mechanisms that reduce energetic costs could increase the production of young. When more energetically constrained, dotterel reduced the energetic cost of incubation by scheduling trips in conditions when the unattended eggs would have cooled more slowly and by making fewer, but longer trips. When suffering severe energetic constraint, some dotterel neglected their eggs for many hours: dotterel embryos' high chilling tolerance may have been necessary for successful uniparental incubation In a cold and unpredictable environment. Dotterel selected nest sites that allowed them to build larger nests with larger linings. Larger, better insulated nests probably decreased heat loss from the eggs and sitting parents, so reducing energetic costs during incubation. Sitting dotterel oriented into the wind, which probably reduced the disruption of their plumage and minimised their energetic expenditure on thermoregulation. In cooler conditions, dotterel changed their nest defence strategy and used energetically cheaper but probably riskier responses to simulated predators. Behaviours may be shaped under conflicting selective pressures and dotterel's management of their high energetic costs during the incubation period was constrained by egg-predation: dotterel's incubation scheduling appeared to be influenced by diurnal variation in the risk of predation and dotterel's nest defence behaviour traded-off energetic costs and the risk of predation. I declare that this thesis has been composed by myself and that it embodies the results of my own research. Where appropriate, I have acknowledged the nature and extent of work carried out in collaboration with others. This thesis presents data collected by myself over 2,212h spent in the alpine study areas from 288 days during my PhD field seasons in 1996,1997 and 1998. I also analyse some of Scottish Natural Heritage's dataset on dotterel biology collected between 1987 and 1999 by a team of fieldworkers, including myself (in Chapters 2,7 and 8).

The functions of the elongated tails of birds have been the subject of much discussion in recent years. It is clear that in some cases the tail represents a sexually selected ornament, playing a vital role in mate choice. However. what is becoming increasingly apparent is that the tail can also play vital aerodynamic roles during flight, and can thus be a result of natural selection. Tail length manipulation experiments carried out during this work have shown that elongated graduated tails have an aerodynamic role during gliding flight. A function in the maintenance of stability (ring necked pheasants (Phasianus colchicus)) and optimising gliding performance (black-billed magpie (Pica pica)). thus these elongated graduated tails have been shown to be a product of natural selection. The question of whether correlated evolution occurred between the advent of gliding flight and the graduated tail shape was investigated. It was found that graduated tails did not co-evolve with gliding flight. However, it was shown that graduated tails had correlated evolution with tail elongated. It has been suggested that the forces acting on a triangular tail can be predicted through the application of slender lifting surface theory and the tail being analogous to a delta wing. This would predict that the tail functioned as a consistent lift producing surface. This study considered whether the tail functioned as a lift producer or a control surface. Stereo video of Harris' hawks (Parabuteo unicinctus) was used to assess tail function of a triangular tail. However, the results did not provide conclusive evidence for either theory. In this thesis I show that elongated avian tails perform a number of naturally selected aerodynamic roles during flight.

Die Feldlerche gehört zur Reihe charakteristischer Vogelarten der offenen Feldflur, deren Bestände in jüngster Zeit stark zurückgegangen sind. Das Heft bietet Art- und Lebensraum bezogene Informationen. Redaktionsschluss: 03.07.2019

Der Atlas behandelt 213 aktuelle und ehemalige Brutvogelarten in Sachsen. Hiervon werden 177 Arten ausführlich mit den Schwerpunkten Verbreitung, Lebensraum, Brutbestand, Phänologie und Brutbiologie sowie Gefährdung und Schutz besprochen. Aus drei Zeitebenen liegen landesweite Bearbeitungen der Brutvogelfauna auf Rasterbasis vor. Die Ergebnisse ermöglichten es, in detaillierten Karten Bestandstrends darzustellen und Veränderungen von Verbreitung und Häufigkeit nachzuvollziehen. 293 Fotos veranschaulichen die Vielfalt der Vogelarten und zeigen ihren typischen Lebensraum.

»Eine Schwalbe macht noch keinen Sommer«, aber sie bringt Leben in oder an das Haus. Leider kennen immer weniger Menschen die lustig schwatzenden Rauchschwalben in Ställen. Auch die Fütterung von jungen Mehlschwalben in ihren Nestern an den Außenseiten von Gebäuden lässt sich immer weniger beobachten. Schwalben brauchen unsere Hilfe. Die reich bebilderte Broschüre gibt Einblick in das interessante Leben der Schwalben. Sie zeigt Möglichkeiten auf, mit welchen meist einfachen Maßnahmen Rauch- und Mehlschwalben unterstützt werden können und wie sich das gemeinsame Wohnen von Mensch und Schwalben unter einem Dach erleichtern lässt. Redaktionsschluss: 13.09.2017

Despite intense publicity, habitat loss still remains a serious threat to biodiversity. Forest destruction is its frontrunner, both in terms of physical habitat under threat and potential for biodiversity loss. In the fragmented landscape of the Taita Hills, SE Kenya, several bird species are facing the threat of extinction from forest loss. They are absent from many of the remnant forest patches and/or are showing negative effects with increasing disturbance. Using a relatively common forest-dependent bird species - the whitestarred robin Pogonocichla stellata - as a model, the current status of this ecosystem was examined, and future patterns predicted in view of the unrelenting destruction. As expected, the robin population in the largest and most intact fragment (c35 ha) was the healthiest, suggesting that this was indeed the best quality habitat patch: it had the highest population density, highest productivity (low nest predation and high juvenile to adult ratio) and lowest turnover rates. Effects of forest deterioration were evident from the fact that the medium-sized patch (c95 ha), which is undergoing severe degradation, was a worse habitat for the robin than the tiny patches (c2-8 ha): it had the lowest population density, lowest productivity (highest nest predation rates and lowest juvenile to adult ratio), and highest turnover rates. The explanation for this is twofold. Besides the smallest patches facing lower levels of habitat loss recently, they also had high levels of dispersal between them. They occasionally operated as a finegrained system with individuals moving between them in the space of a few days. In general, the robin metapopulation is demographically (rate of change, λ = 0.996) and genetically (at migration- and mutation-drift equilibrium) stable at present. The populations in the largest and smallest patches were potential sources providing emigrants that were possibly crucial in sustaining the population in the medium-sized patch (given its low productivity and high turnover rates). Overall, these findings underscore the importance of within-patch processes, both for ensuring persistence of subpopulations and providing dispersers, as well as between-patch processes (chiefly dispersal) for ensuring metapopulation persistence. Thus, by furnishing ample sample sizes that enabled work to be carried out in all fragments throughout this landscape, the model species approach was useful for identifying the need for a two-pronged conservation strategy. First, a need to focus within fragments to reduce habitat loss and degradation, and second, to address among fragment issues relating to land-use and maintaining a forested landscape, in order to enhance connectivity between patches. Finally, based on the mechanisms by which disturbance and fragmentation are affecting bird populations e.g. predator influxes from the surrounding matrix, conservation recommendations for the Taita Hills are offered.

Understanding physiological processes is key to answering the questions of why organisms behave in the way they do, and how they interact with each other, and their environment. Despite technological innovations in recent decades, assessment of physiological state in free-living animals still generally requires subjects to be trapped and handled, so tissues or blood can be sampled, or so measurement devices can be attached or implanted. Such methods limit research to species and individuals that can be caught, potentially restricting the generalisability of findings, and introducing bias. Additionally, natural behaviours are interrupted, and subsequent physiology, behaviour or performance may be altered as a result of the stress of capture, the burden of attached apparatus, or the effects of surgery. Consequently, alternative techniques such as inferring physiological state from traits that do not require invasive sampling would be a valuable development. Body temperature is a particularly promising candidate trait, linked with an array of physiological functions, and having previously been used as a proxy for metabolic activity, stress state and immune challenge. With the advent of low cost, highly portable thermal imaging cameras, physiological ecologists are now presented with unprecedented opportunities to measure body surface temperature non-invasively, and at high frequencies from free-living animals. In this thesis, I investigated relationships between body surface temperatures, measured using thermal imaging from free-living blue tits or captive zebra finches, with physiological measures or situations relevant to the assessment of physiological state. I developed reliable thermal imaging techniques to take non-invasive measurements of body surface temperatures in a variety of contexts, allowing characterisation of physiological responses in real time. My studies of captive birds revealed that activity levels influence body surface temperatures measured from free moving animals, and so should be accounted for in experimental designs. I also successfully acquired body surface temperatures from overwintering blue tits visiting food-baited traps, and from breeding blue tits entering and leaving their nest. Using this data, I showed that body surface temperature exhibits a characteristic response to acute stress, which differs with stressor type. While the mechanisms require explanation, much potentially useful information appears to be stored within body surface temperature dynamics during acute stress. Additionally, I established links between body surface temperature and longer term physiological processes in free-living blue tits. I observed near identical correlations between body surface temperature and body condition across differing seasons and life history stages. Also, I found evidence suggesting both that repeated acute stressors (predation risk and human disturbance) had a chronic effect on body condition breeding blue tits, and that surface temperature in those birds was linked to body condition. If confirmed, these results would be particularly interesting in a conservation physiology context, as it may prove possible to detect a signal of persistent physiological effect(s) relating to human disturbance, non-invasively. Furthermore, my discovery of a further correlation between baseline plasma glucocorticoids and body surface temperature in overwintering birds implies links with the hypothalamic-pituitary-adrenal axis. All of these results combined suggest that body surface temperatures measured using thermal imaging are highly likely to prove useful in determining aspects of physiological state non-invasively from free-living animals. While further investigation and validations are necessary, this work has laid the foundations for an exciting new methodology that could help solve many questions that remain unanswerable using current techniques.

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