As anthropogenic stress increasingly affects the viability of natural populations of animals and plants, conservation ecologists are challenged to identify vulnerable populations before their demographic and/or genetic properties become irreversibly affected. Since traditional biomarkers of anthropogenic stress are often cumbersome to measure, and populations may thus go extinct before appropriate data can be obtained, there is a growing interest in individual-based markers that do not require repeated captures, are relatively easy to measure, and allow mitigating action one step ahead. One such marker, left-right asymmetry in bilateral symmetrical traits (“fluctuating asymmetry”, FA) has become an established bioassay of the quality and health of individuals and populations in evolutionary-ecological studies. However, the lack of a theoretical framework that predicts under which ecological conditions relationships between FA, stress and fitness can be expected, continues to hamper the use of FA in applied conservation. Here, we briefly review the concept, measurement and analysis of FA, and appraise its expediency in a selection of 21 avian studies covering environmental or genetic stress commonly encountered in conservation biology. The majority of studies met the basic statistical requirements of FA analysis, and two-thirds reported significant, positive relationships with environmental or genetic stress, although with substantial variation among traits, stresses, ages and sexes. In most cases, the observed heterogeneity in relationships with FA could be explained by taking into account both methodological and conceptual issues. Effect sizes ranged from very small (0.02) to very large (0.76), with a weighted average of 0.30, indicating that on average 9% of variance in the variable of interest was explained by FA. Given the intrinsic difficulties associated with FA analysis, conservation ecologists are advised to combine information from FA with that of other individual-based biomarkers, such as the study of growth-bar dimensions on developing feathers.

This study reviews the use of remotely triggered still cameras, known as camera traps, in bird research and suggests new methods useful for analyzing camera trap data. Camera trapping may be most appropriate for large, ground-dwelling birds, such as cracids and pheasants. Recent applications include documentation of occurrence of rare species and new species records, nest predation studies and behavioural studies including nest defence, frugivory, seed dispersal, and activity budgets. If bird postures are analyzed, it may be possible to develop behavioural time budgets. If birds are marked or individually identifiable, abundance may be estimated through capture-recapture methods typically used for mammals. We discourage use of relative abundance indices based on trapping effort because of the difficulty of standardizing surveys over time and space. Using the Great Argus Pheasant Argus argusianus, a cryptic, terrestrial, forest bird as an example, we illustrate applications of occupancy analysis to estimate proportion of occupied habitat and finite mixture models to estimate abundance when individual identification is not possible. These analyses are useful because they incorporate detection probabilities < 1 and covariates that affect the sample site or the observation process. Results are from camera trap surveys in the 3,568 km2 Bukit Barisan Selatan National Park, Indonesia. We confirmed that Great Argus Pheasants prefer primary forest below 500 m. We also find a decline in occupancy (6–8% yr−1). Point estimates of abundance peak in 2000, followed by a sharp decline. We discuss the effects of rarity, detection probability and sampling effort on accuracy and precision of estimates.

There is a great need for increased use and further development of automated sound recording and analysis of avian sounds. Birds are critical to ecosystem functioning so techniques to make avian monitoring more efficient and accurate will greatly benefit science and conservation efforts. We provide an overview of the hardware approaches to automated sound recording as well as an overview of the prominent techniques used in software to automatically detect and classify avian sound. We provide a comparative summary of examples of three general categories of hardware solutions for automating sound recording which include a hardware interface for a scheduling timer to control a standalone commercial recorder, a programmable recording device, and a single board computer. We also describe examples of the two main approaches to improving microphone performance for automated recorders through small arrays of microphone elements and using waveguides. For the purposes of thinking about automated sound analysis, we suggest five basic sound fragment types of avian sound and discuss a variety of techniques to automatically detect and classify avian sounds to species level, as well as their limitations. A variety of the features to measure for the various call types are provided, along with a variety of classification methods for those features. They are discussed in context of general performance as well as the monitoring and conservation efforts they are used in.

Understanding how avian populations are structured spatially and temporally is fundamental to their effective conservation. Protecting migratory species in one jurisdiction or period of the annual cycle may be ineffective if they periodically move to areas where they are not protected or are exposed to factors that limit populations or cause their decline. Unfortunately, for most species, our understanding of connectivity between breeding, wintering or stopover sites during the annual cycle are poorly understood and there is an urgent need to define such connections in order to achieve more effective conservation. This paper provides an overview of the methods used to mark individuals in order to track their movements. Passive exogenous markers such as numbered rings or bands are typically ineffective for most avian species. Active exogenous markers such as satellite tags have provided significant breakthroughs but are still prohibitive financially and still cannot be applied to species under 200g. Endogenous markers such as DNA markers, trace elements and stable isotopes show significant promise as a means of moving forward the field of animal tracking. The advantage of these endogenous approaches is that they depend only on sampling a population once and so are not biased by limitations of mark-recapture methods. Nonetheless, all methods have disadvantages and the path ahead must consider multiple approaches to tracking avian populations.

Wild bird conservation in the UK is a widely regarded as a success story. The populations of many endangered species have grown or at least stabilised, birds that were last seen in the UK over 100 years ago have been successfully re-introduced, and bird watching makes an increasingly important contribution to the rural economy in terms of employment and income. Nevertheless, some wild birds also generate costs and some deep rooted conflicts persist with other rural activities such as farming and game shooting. This paper describes a conceptual framework for understanding the costs and benefits of wild birds and, using wild goose conservation in the island of Islay as a case study, explores whether continued public investment in wild goose conservation is worthwhile from an economic perspective. The paper concludes with a discussion about future options for integrating wild bird conservation with sustainable rural development.

In this paper, we argue that bird atlases, and the databases from which they are produced, are becoming increasingly valuable resources – but only in some parts of the world. There is a striking lack of atlases for almost all of the world's species-rich areas, most notably tropical America and tropical Asia. Yet even comparatively modest data sets (we take Uganda as an example) can be used to create an atlas. Further, their data can yield interesting information with clear value for conservation planning. For instance, we can see that Uganda's main savanna parks are quite well-placed in relation to raptor species richness, whilst other species of conservation concern are less well covered. In contrast, the fine-scale data-rich atlas projects in many American and European countries provide detailed information of great value. Taking examples from England, we show some of their uses in planning both for physical developments and for conservation. Repeating atlas projects after an interval of several years highlights changing distributions and, increasingly, changing levels of abundance. We believe that every encouragement should be given to new (and repeat) atlasing projects - but most especially in the tropics.

Global and regional targets to reduce the rate of biodiversity loss bring with them the need to measure the state of nature and how it is changing. A number of different biodiversity indicators have been developed in response and here we consider bird population indicators in Europe. Birds are often used as surrogates for other elements of biodiversity because they are so well known and well studied, and not for their unique intrinsic value as environmental indicators. Yet, in certain situations and at particular scales, trends in bird populations correlate with those of other taxa making them a valuable biodiversity indicator with appropriate caveats. In this paper, we look at two case studies, in the UK and Europe as a whole, where headline bird indicators, that is, summary statistics based on bird population trends, have been developed and used to inform and assist policy makers. Wild bird indicators have been adopted by many European countries and by the European Union as indicators of biodiversity and of sustainable development. In the discussion, we review the strengths and weaknesses of using bird populations in this way, and look forward to how this work might be developed and expanded.

After habitat loss and degradation, the leading threats to biodiversity are over-exploitation and invasive alien species. For birds, newly synthesised data using the standard classification schemes for utilisation and threat types for the IUCN Red List allow novel analyses on the importance of these threats and permit the calculation of Red List Indices (RLIs) to show trends in the status of birds driven by these factors. At least 45.7% of extant bird species (4,561 species) are used by humans, principally for pets (37.0%) and for hunting for food (14.2%), but other uses include sport hunting, ornamentation and traditional medicine. Much of this use drives trade at an international scale, involving at least 3,337 species (33.9%, substantially higher than previous estimates), mostly for the pet trade. RLIs show that although successful control and management of use and trade have led to some species improving in status, this has been outweighed by the number of species deteriorating in status owing to unsustainable exploitation. Overall, the RLI showing trends in extinction risk driven by issues related to use shows a negative slope: human use of birds is currently unsustainable. Similarly, and of relevance to the Convention on the International Trade in Endangered Species (CITES), the RLI for internationally traded bird species showing trends in extinction risk driven by issues related to international trade is also declining: international trade remains a threat to the world's birds. Invasive species impact at least one third of the world's threatened bird species (398 species, 32.6%), with mammals being the most important (impacting 81.1%), particularly through predation by carnivores and rodents. The RLI illustrating impacts of invasive species shows that they are driving a deterioration in the status of the world's birds. RLIs for the impacts of use and invasive species will be important indicators to help track progress towards the target of significantly reducing biodiversity loss by 2010.