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Animal tolerance towards humans can be a key factor facilitating wildlife-human coexistence, yet traits predicting its direction and magnitude across tropical animals are poorly known. Using 10,249 observations for 842 bird species inhabiting open tropical ecosystems in Africa, South America, and Australia, we find that avian tolerance towards humans was lower (i.e., escape distance was longer) in rural rather than urban populations and in populations exposed to lower human disturbance (measured as human footprint index). In addition, larger species and species with larger clutches and enhanced flight ability are less tolerant to human approaches and escape distances increase when birds were approached during the wet season compared to the dry season and from longer starting distances. Identification of key factors affecting animal tolerance towards humans across large spatial and taxonomic scales may help us to better understand and predict the patterns of species distributions in the Anthropocene., (© 2023. The Author(s).)

Wildlife trade has rapidly expanded on social media platforms in recent years, offering an easy means for traders to access international markets. Investigating this trade activity poses a complex challenge to researchers seeking to understand online trade and moderators seeking to disrupt illicit and harmful activity. Current survey methods frequently rely on text-based searches and focus on posts in which the advertisement is explicit. However, such approaches risk overlooking a growing volume of relevant content, particularly outside social media groups. We used posts from pages promoting West African birds for trade as a case study to explore the availability of information for making inferences about trade activity on social media, specifically information indicating that trade activity was occurring or that could be used to infer trade routes. We recorded 400 posts from 12 pages that we inferred either promoted or facilitated wildlife trade, of which 19.7% were explicit advertisements and 23.8% contained taxa-related terms. In the remaining 341 posts, profile information was the most common indicator of trade activity, but a variety of indicators (e.g., images of birds in trade and trade enquiries) were identified across imagery, text, and comments. We identified multiple types of geographical information that could help infer trade routes and thus the likely legality of trade, although most were relatively rare and sometimes contradictory. Our findings suggest that triangulating multiple types of information from within, across, and beyond posts is vital for effectively identifying and interpreting wildlife trade content on social media. Therefore, were commend that expert-mediated triangulation should be integrated in and used alongside automated detection systems and moderating practices of social media companies., (© 2021 Society for Conservation Biology.)

Psittacine beak and feather disease (PBFD), caused by Beak and feather disease virus (BFDV), has spread rapidly around the world, raising concerns for threatened species conservation and biosecurity associated with the global pet bird trade. The virus has been reported in several wild parrot populations, but data are lacking for many taxa and geographical areas with high parrot endemism. We aimed to advance understanding of BFDV distribution in many data-deficient areas and determine phylogenetic and biogeographic associations of the virus in 5 parrot species across Africa, the Indian Ocean islands, Asia, and Europe and focused specifically on the highly traded and invasive Psittacula krameri. Blood, feather, and tissue samples were screened for BFDV through standard polymerase chain reaction. Isolates obtained from positive individuals were then analyzed in a maximum likelihood phylogeny along with all other publically available global BFDV sequences. We detected BFDV in 8 countries where it was not known to occur previously, indicating the virus is more widely distributed than currently recognized. We documented for the first time the presence of BFDV in wild populations of P. krameri within its native range in Asia and Africa. We detected BFDV among introduced P. krameri in Mauritius and the Seychelles, raising concerns for island endemic species in the region. Phylogenetic relationships between viral sequences showed likely pathways of transmission between populations in southern Asia and western Africa. A high degree of phylogenetic relatedness between viral variants from geographically distant populations suggests recent introductions, likely driven by global trade. These findings highlight the need for effective regulation of international trade in live parrots, particularly in regions with high parrot endemism or vulnerable taxa where P. krameri could act as a reservoir host., (© 2018 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.)

Psittacine beak and feather disease (PBFD) has emerged in recent years as a major threat to wild parrot populations and is an increasing concern to aviculturists and managers of captive populations. Pathological and serological tests for screening for the presence of beak and feather disease virus (BFDV) are a critical component of efforts to manage the disease and of epidemiological studies. Since the disease was first reported in the mid-1970s, screening for BFDV has been conducted in numerous wild and captive populations. However, at present, there is no current and readily accessible synthesis of screening efforts and their results. Here, we consolidate information collected from 83 PBFD- and BFDV-based publications on the primary screening methods being used and identify important knowledge gaps regarding potential global disease hotspots. We present trends in research intensity in this field and critically discuss advances in screening techniques and their applications to both aviculture and to the management of threatened wild populations. Finally, we provide an overview of estimates of BFDV prevalence in captive and wild flocks alongside a complete list of all psittacine species in which the virus has been confirmed. Our evaluation highlights the need for standardised diagnostic tests and more emphasis on studies of wild populations, particularly in view of the intrinsic connection between global trade in companion birds and the spread of novel BFDV strains into wild populations. Increased emphasis should be placed on the screening of captive and wild parrot populations within their countries of origin across the Americas, Africa and Asia.

Psittacine beak and feather disease (PBFD), the most prevalent viral disease affecting psittacines, is caused by beak and feather disease virus (BFDV). This study assessed viral load using qPCR in a wild Cape parrot population affected by PBFD and compared it to overall physical condition based on clinical signs attributable to PBFD. A significant inverse correlation between viral load and overall physical condition was found, which confirmed that clinical signs may confidently be used to diagnose the relative severity of BFDV infections in wild populations. This is the first assessment of BFDV viral load in a wild psittacine population.

Captive and wild psittacines are vulnerable to the highly contagious psittacine beak and feather disease. The causative agent, beak and feather disease virus (BFDV), was recently detected in the largest remaining population of endangered Cape parrots (Poicepahlus robustus), which are endemic to South Africa. Full-length genomes were isolated and sequenced from 26 blood samples collected from wild and captive Cape parrots to determine possible origins of infection. All sequences had characteristic BFDV sequence motifs and were similar in length to those described in the literature. However, BFDV coat protein (CP) sequences from this study did not contain a previously identified bipartite nuclear localisation signal (NLS) within residues 39-56, which indicates that an alternate NLS is involved in shuttling the CP into the nucleus. Sequences from the wild population shared a high degree of similarity, irrespective of year or location, suggesting that the disease outbreak occurred close to the time when the samples were collected. Phylogenetic analysis of full-length genomes showed that the captive Cape parrot sequences cluster with those isolated from captive-bred budgerigars in KwaZulu-Natal Province, South Africa. Exposure to captive-bred Cape parrots from a breeding facility in KwaZulu-Natal is suggested as a possible source for the virus infection. Phylogenetic analysis of BFDV isolates from wild and captive Cape parrots indicated two separate infection events in different populations, which highlights the potential risk of introducing new strains of the virus into the wild population. The present study represents the first systematic investigation of BFDV virus diversity in the southern-most population of Cape parrots.

Frequency, duration, and intensity of hot-weather events are all predicted to increase with climate warming. Despite this, mechanisms by which temperature increases affect individual fitness and drive population-level changes are poorly understood. We investigated the link between daily maximum air temperature (tmax) and breeding success of Kalahari common fiscals (Lanius collaris) in terms of the daily effect on nestling body-mass gain, and the cumulative effect on size and age of fledglings. High tmax reduced mass gain of younger, but not older nestlings and average nestling-period tmax did not affect fledgling size. Instead, the frequency with which tmax exceeded critical thresholds (tcrits) significantly reduced fledging body mass (tcrit = 33°C) and tarsus length (tcrit= 37°C), as well as delaying fledging (tcrit= 35°C). Nest failure risk was 4.2% per day therefore delays reduced fledging probability. Smaller size at fledging often correlates with reduced lifetime fitness and might also underlie documented adult body-size reductions in desert birds in relation to climate warming. Temperature thresholds above which organisms incur fitness costs are probably common, as physiological responses to temperature are non-linear. Understanding the shape of the relationship between temperature and fitness has implications for our ability to predict species' responses to climate change.

Recent mass mortalities of bats, birds and even humans highlight the substantial threats that rising global temperatures pose for endotherms. Although less dramatic, sublethal fitness costs of high temperatures may be considerable and result in changing population demographics. Endothermic animals exposed to high environmental temperatures can adjust their behaviour (e.g. reducing activity) or physiology (e.g. elevating rates of evaporative water loss) to maintain body temperatures within tolerable limits. The fitness consequences of these adjustments, in terms of the ability to balance water and energy budgets and therefore maintain body condition, are poorly known. We investigated the effects of daily maximum temperature on foraging and thermoregulatory behaviour as well as maintenance of body condition in a wild, habituated population of Southern Pied Babblers Turdoides bicolor. These birds inhabit a hot, arid area of southern Africa where they commonly experience environmental temperatures exceeding optimal body temperatures. Repeated measurements of individual behaviour and body mass were taken across days varying in maximum air temperature. Contrary to expectations, foraging effort was unaffected by daily maximum temperature. Foraging efficiency, however, was lower on hotter days and this was reflected in a drop in body mass on hotter days. When maximum air temperatures exceeded 35.5 °C, individuals no longer gained sufficient weight to counter typical overnight weight loss. This reduction in foraging efficiency is likely driven, in part, by a trade-off with the need to engage in heat-dissipation behaviours. When we controlled for temperature, individuals that actively dissipated heat while continuing to forage experienced a dramatic decrease in their foraging efficiency. This study demonstrates the value of investigations of temperature-dependent behaviour in the context of impacts on body condition, and suggests that increasingly high temperatures will have negative implications for the fitness of these arid-zone birds., (© 2012 Blackwell Publishing Ltd.)