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Red-crowned Grus japonensis (IUCN status: Endangered) and White-naped Antigone vipio (IUCN status: Vulnerable) cranes are both rare, with wild populations of ∼3,000 and ∼6,000 individuals, respectively. Since 1991, the Rare Bird Reintroduction Station at the Khingansky State Nature Reserve, Russia, has been rearing and reintroducing chicks of both species to bolster wild populations. The station uses two different chick-rearing methods: (1) the “parent-reared” method, in which chicks are raised in enclosures by natural parents and stay with them until their release into the wild, and (2) the “semi-wild” method, a modification of hand-rearing, in which cohorts of 2–7 chicks spend most of their time together in an enclosure but are guided on daily excursions outside the enclosure, under supervision of a keeper from a distance of 30–50 m. We have assessed and compared apparent survival of crane chicks reared under these methods. Of the 165 juveniles released into the wild from 1991–2019 (104 Red-crowned; 61 White-naped), no difference was found between apparent survival of parent-reared and semi-wild chicks. Six-month apparent survival of Red-crowned Cranes was 84.2% (95% confidence interval: 75.3–90.3%); for White-naped Cranes –89.5% (95% CI: 83.9–93.3%). Both parent-reared and semi-wild chicks were later observed in mated pairs with their own offspring (17 chicks in total), coupling with either other reintroduced birds or with wild individuals. We conclude that both the parent-reared and semi-wild methods had similar outcomes with respect to apparent survival. However, since the semi-wild method is less costly with respect to time (i.e., more juveniles can be released annually using this method) we recommend that it be used whenever possible to bolster these Endangered and Vulnerable populations.

Understanding the behavioural responses of bird species to their environments is important for effective conservation, especially in captive-management and resource-provisioning programs. Camera traps present a growing opportunity to research bird breeding and foraging behaviour in situ. Remotely triggered cameras are commonly deployed to study mammals and large terrestrial birds. They are rarely used to survey small or arboreal birds due to habitat constraints. However, a wealth of information about small or arboreal birds can be generated opportunistically from camera traps in the course of collecting data on other taxa. Here, we describe and quantify the types of behavioural information that can be so gleaned, based on over 1,700 small-bird images captured as “collateral” during a geographically extensive mammal-focused camera study in Tasmania, Australia in 2018–2020. Postural analysis of images revealed 10 distinct behaviours. Large- and medium-sized terrestrial bird species were most commonly observed (61.6% of behavioural images), but small and arboreal species were also photographed at high rates (18.4% and 29.5% of behavioural images respectively). Investigative activity was the most commonly observed behaviour in small and arboreal species (around half of all images), but feeding, mating and even very rare behaviours like fur plucking, were also captured photographically. This case study reveals the value of opportunistically analysing camera trap images for small or arboreal birds species, especially when they are of conservation interest, even for cases where deliberately targeting them would not be a cost-effective strategy.

Parental role division is common among monogamous birds. Among raptors, males typically expend more effort to feed their chicks than do females, yet few studies have focused on how each pair establishes this role division. Therefore, in this study we examined the mechanism of role division in the Ryukyu Scops Owls Otus elegans on Minami-daito Island. Pairs of this species typically remain together and use the same nest over several years, so there is a possibility that their role division improves with experience over time. To clarify this, we studied the feeding frequency and territorial usage of individuals. Males fed their chicks more frequently than females, and experienced individuals using the same nests fed their chicks more than inexperienced individuals. On comparing experienced and inexperienced pairs, we found that experienced individuals hunted closer to the nest than inexperienced individuals. Furthermore, the home ranges of the males and females of experienced pairs, overlapped less than those of inexperienced pairs. Experience of using a nest site in consecutive years may allow such individual behavioural differences to develop and be involved in role division in parental care.

The Indian coast and its adjacent wetlands host large congregations of shorebirds, including winter and passage migrants of high conservation priority, along the Central Asian Flyway. Identifying crucial wintering and stopover sites and seasons is an important step toward conserving shorebirds and their habitats along the Indian coast. We assessed spatial and temporal patterns of shorebird composition from January 2015 to December 2016 at seven estuaries along Maharashtra's Sindhudurg district, which is located on India's west coast, a coastal zone of international importance for shorebirds. Three potential shorebird habitats –mangroves, mudflats, and sandy beaches – were selected at each of the estuaries chosen for the study. We established three vantage points, one each in the mangrove, mudflat, and sandy beach areas, to count birds during low tide. The total count method was followed to count birds, and occasional photograph-based counts were also made when flock size was big or the flocks kept changing. We recorded 31 species of migratory shorebirds, of which 68% wintered and 32% used the Sindhudurg coast as migratory stopover site. We found significantly high richness and abundance of shorebirds during winter and in the mudflats. nMDS was used to determine species composition of shorebird across habitats and months and revealed distinct patterns of composition in five unique phases: arrival, wintering, early departure, departure, and breeding. Our results revealed that the species composition of shorebirds is not homogenous across sites and months, and is largely driven by the habitat heterogeneity of estuaries, seasonality, and anthropogenic disturbances. These results provide baseline information on shorebirds along a stretch of India's west coast and highlight the importance of mudflats and non-protected coastal wetlands for shorebirds.

Little Tern Sternula albifrons sinensis was been categorized as Endangered Class II by the 2020 Ministry of the Environment's Red List in Japan. For an effective conservation program for the taxon, the unit of conservation needs to be understood. In this study, we investigated genetic and morphological diversity as a clue to clarify the units to be protected. Blood samples were collected from 47 individuals in four different breeding sites in Japan (Tokyo, Chiba, Fukuoka, Okinawa). The nucleotide sequences of the control region of mitochondrial DNA were used to analyze their genetic diversity and structure. Basic morphological features were also compared. Nucleic acid base substitution, deletion, or insertion were identified at 30 sites of the 1029-bp sequence alignment of the control region, leading to identification of 30 different haplotypes. Genetic diversity was high in the four breeding populations, and haplotype frequencies showed no indication that specific genotypes were present at extreme frequencies. This suggests that the population of Little Tern nesting in Japan has been maintained without recent bottleneck events. The haplotype network formed two major haplotype groups from the 30 haplotypes. Haplotypes of one group were abundant in the Tokyo, Chiba, and Fukuoka populations. In contrast, those of the other group were frequent in the Okinawa population. Pairwise haplotype analysis between populations also revealed that the genetic variations at Okinawa differ from those of the remaining three populations. Furthermore, the Okinawa population showed different morphological characteristics compared to the Tokyo/Chiba populations. These results collectively suggest that the population of Little Terns in Japan is divided into at least two different populations.

Research into the breeding ecology of birds is key to understanding the evolution of life-history traits and developing effective species conservation measures. We studied the breeding ecology of the Crested Myna Acridotheres cristatellus on tropical Hainan Island, China, throughout the breeding season from March to August in 2018 and 2019. Parents Crested Myna build disk-shaped nests together and take turns to incubate their eggs and feed their nestlings, with a nestling period of 18–22 days. Eggs were pure blue-green, and the clutch sizes were 3–6 eggs (averaging 4). Egg mass, egg size, and egg volume were 6.78±0.50 g, 28.74±1.20 mm×21.13±0.53 mm, and 6.56±0.50 cm³, respectively (N=274). Egg-laying mainly occurred between 0700 to 1000, and the average time for laying one egg was 172.36±28.29 s (N=11). Feeding frequency during the mid-nestling period was significantly higher than in the early periods (N=55). The Crested Myna population on tropical Hainan nested earlier, laid eggs earlier and had a longer breeding period than populations in the temperate zone.

We studied the pattern of acquisition of breeding positions among helpers in a population of Grey-crowned Babblers Pomatostomus temporalis rubecula in the monsoon tropics of northwestern Australia, using both behavioural and molecular data. In particular, we focused on sex differences, kinship, and their interactions among emigrating helpers. Moreover, we also considered whether intergroup movement and extra-pair mating contributed to incest avoidance in our population. The advantage of this material is that there are previous studies of populations in different regions, and the comparison of the results may provide a better understanding of ecological factors driving helping behaviour in cooperative breeding. Three options for a mature helper to acquire a breeding position were observed: establishing a new territory, emigrating to an existing territory, or waiting in the natal territory for a breeding vacancy. In many cases, male helpers took the third option, while female helpers took the second one. Our population of Grey-crowned Babblers seemed not to be actively avoiding incest. Female helpers tended to disperse from natal groups more than males, but neither intergroup movements nor extra-pair mating were effective in avoiding incestuous breeding. In some groups, dominant breeders were closely related to each other. The frequency of extra-pair mating in our population was similar to that of the New South Wales population previously studied, but dispersal distances were twice as great. The two populations also differ in mean clutch size and group size. Such variation in life history characteristics among different populations of cooperatively breeding species has received little attention, but has the potential to explain how cooperative breeding systems are modified by environmental factors.

The Asian Woollyneck Ciconia episcopus is a stork found throughout Asia whose international conservation status is currently being considered for reclassification from vulnerable to near-threatened. However, much of what is known about this species is fragmented across observational reports and small studies making a comprehensive assessment of population trends difficult. Here, we bring together all available published information to see what is known and what research questions still need answering in order to make reliable assessments of regional population trends and identify probable drivers of decline. Despite the species likely being extinct in the extremes of its former range and evidence of dramatic declines in Southeast Asia, Asian Woollyneck appears to be stable or increasing in India, Sri Lanka and Nepal. Observations of its preferred foraging and nesting habitats in South versus Southeast Asia show some obvious differences that may explain regional variations in population trends. In South Asia the bird is common in open grasslands and agricultural areas, while in Southeast Asia it is mostly observed in forested areas. Also, reports of the Asian Woollyneck nesting on cell phone towers is increasing in South Asia. However, because of a severe lack of reporting from Southeast Asia, it is unclear if or how these regional differences in population trends and habitat use are linked. Structured surveys and studies into the Asian Woollyneck foraging, nesting and movement ecology are urgently needed to understand the extent and drivers of decline in Southeast Asia. Therefore, researchers should focus future studies on population trends across the species' range, and aim to identify the local factors influencing recent changes in population growth. Without such knowledge, reassessment of its conservation status may be premature.