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The Journal of Avian Biology (JAB) publishes high-quality research on birds' ecology, evolution, and behavior from around the world. To provide a more nimble format for publishing overviews in avian biology, JAB introduced the 'mini-review' article category in 2022. The journal also established the 'JAB review award' to recognize exceptional mini-review manuscripts from early career researchers, with winners receiving a 1000€ honorarium. The competition aims to highlight new developments in avian research and encourage submissions from underrepresented groups and geographic areas. [Extracted from the article]

The ability to monitor developing avian embryos and their associated vascular system via candling enables the application of important reproductive management techniques. Egg candling facilitates the confirmation of egg viability throughout the incubation process and identification of a precise position on a vein for the safe extraction of blood. Blood samples may then be analysed to retrieve vital health and genetic information to assist in conservation management. However, the thick or opaque egg shell characteristics of some avian species prevents the observation of egg contents using traditional candling methods, thus limiting management options. This paper tests a novel method of preparing thick‐shelled or opaque eggs so that traditional egg candling and blood extraction methods may be applied. Eggs from captive emu (Dromaius novaehollandiae, Latham 1790) and southern cassowary (Casuarius casuarius johnsonii, Linnaeus 1758) were obtained, and partial fenestration was performed on two areas of shell either before incubation or at ⅓ of incubation. Hatchability and weight loss were examined as a measure of effect of the fenestration process on the developing embryo. Clear observation of vascular development was successful in 97% of viable fenestrated eggs, without affecting hatchability or weight loss. Blood samples were taken from developing embryos and DNA was successfully extracted for proof of concept of this new technique. The ability to observe vascular development and monitor the developing embryo in thick and opaque eggs will significantly improve both in situ and ex situ population management options such as in ovo sexing in species of concern. Research Highlights: 1.The fenestration of two sites on the shell surface extends the use of traditional candling methods to thick and opaque eggs, without harmful effects on the embryo.2.Early observation of the vascular system in thick and opaque eggs facilitates additional reproductive technologies and improves management options. [ABSTRACT FROM AUTHOR]

Wildfires are increasing in both frequency and intensity in many ecosystems, with climate change models predicting further escalations in fire-prone environments. Set against this background is the global decline of amphibians, with up to 40% of species facing extinction from multiple additive threats. Despite these disturbing figures, it is currently unclear how increasing fire frequency may impact the long-term persistence of frog populations., Following a severe wildfire in south-eastern Australia in 2009, field surveys indicated healthy tree frog populations. However, the 2009 fire had significant impacts on genetic diversity, including increased levels of inbreeding and declines in effective population size., Using stochastic population modelling under a range of fire-frequency scenarios, we demonstrate that amphibian populations in fire-prone environments may be increasingly vulnerable to extinction, particularly where rates of immigration are low., Synthesis and applications. This study of amphibian population genetics before and after a major wildfire emphasizes the importance of integrating both ecological and genetic data into population models. This will help managers make more appropriate conservation decisions regarding fire management of natural environments, especially those containing threatened populations. Priorities for agencies involved in planning controlled burns should consider carefully the timing of controlled burns, along with maintaining habitat connectivity. [ABSTRACT FROM AUTHOR]

Studies on the impact of climate change on the distributions of bird species in Europe have largely focused on one season at a time, especially concerning summer breeding ranges. We investigated whether migratory bird species show consistent range shifts over the past 55 yr in both breeding and wintering areas or if these shifts are independent. We then analyzed whether patterns in changing migration distances of Finnish breeding birds could be explained by habitat use, phylogeny or body size. We used long-term datasets from the Finnish ringing centre to analyze the mean wintering latitudes of 29 species of Finnish breeding birds, then used breeding distribution data to make predictions as to whether certain species were migrating shorter or longer distances based on the comparative shifts in the wintering and breeding grounds. Our data reveal species-specific differences in changing migration distances. We show that for many species, long-term shifts in wintering ranges have not followed the same patterns as those in the breeding range, leading to differences in migration distances over time. We conclude that species are not adjusting predictably to climate change in their wintering grounds, leading to changing migration distances in some, but not all, species breeding in Finland. This research fills an important gap in the current climate change biology literature, focusing on individuals' entire life histories and revealing new complexities in range shift patterns. [ABSTRACT FROM AUTHOR]

Over the past two decades, studies of songbird populations have detected decreases in the reproductive success of individuals living in urban areas. Anthropogenic noise is considered to be particularly detrimental, however the exact relationship between noise and reproductive success is still unclear because noise is often correlated with many other detrimental factors (e.g., predation, reduced territory quality). We used an experiment to specifically test the effects of urban noise on reproduction of captive zebra finches (Taeniopygia guttata). We found that latency to breed and the size of successfully fledged clutches were consistent between groups, however success of initial nesting attempts was reduced by traffic noise. Further, this reduced success leading to increased numbers of nesting attempts by birds in the noise condition was due to higher levels of embryo mortality in the traffic noise treatment group, which also suffered a lag in nestling growth rates during the first two weeks post-hatch. While parental baseline circulating corticosterone was not chronically affected by noise treatment, we identified some interaction effects whereby certain reproductive measures (laying latency and clutch size) were most strongly affected by treatment when mothers had higher levels of baseline corticosterone. These results indicate that traffic noise may reduce reproductive success through changes in parental behaviour, and that traffic noise may disproportionately affect chronically stressed individuals during reproduction. [ABSTRACT FROM AUTHOR]

Differences in song repertoires and characteristics of island and mainland populations of the same avian species are usually explained by dispersal, cultural evolution and/or habitat differences. The influence of morphology is often overlooked, even though island populations are frequently morphologically distinct from mainland populations, and morphology could affect vocalizations. I compared morphological features, songs, contact calls and alarm calls of six isolated island populations of silvereye Zosterops lateralis with those of two mainland populations to examine whether differences between mainland and island vocalizations were consistent across vocalization types, and whether these differences could be linked to morphological differences. Vocalizations were lower in frequency on islands. Island individuals were larger (both in mass and body structure), and body mass was an important predictor of frequency in contact and alarm calls. I argue that this strong association results from the island rule (islands promote larger body sizes) and cascading effects of morphology on vocalization frequency in this species. [ABSTRACT FROM AUTHOR]