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Copyright of Journal of Field Ornithology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sugar-water bird feeding in residential backyards is increasingly popular, but its effects on wildlife are poorly understood. One concern is whether it results in maladaptive behaviour, such as reliance on artificial food or increased aggression due to increased density of visiting individuals. We studied sugar-water feeder-associated bird behaviour in two cities with different climates. We investigate whether season, city, or sugar concentration influenced bird foraging activity and aggressiveness. We then test whether feeder presence affected backyard bird composition. Birds were most aggressive and used sugar-water feeders most actively in winter, especially the omnivorous native tauhou (Zosterops lateralis). We also found city and seasonal differences in sugar-water feeder usage and aggression. Further, in Auckland, the city with the warmer climate, New Zealand's largest nectarivorous species, tūī (Prosthemadera novaeseelandiae), was more likely to be aggressive at feeders with higher sugar concentrations but foraged longer at feeders with lower sugar concentrations. Neither feeder presence nor sugar concentration influenced garden bird species richness or abundance. We discuss the effects of sugar-water feeding on bird behaviour at the global and local scale and suggest future study directions. [ABSTRACT FROM AUTHOR]

Artificial light at night (ALAN) is a growing conservation concern for seabirds, which can become disoriented and grounded by lights from buildings, bridges and boats. Many fledgling seabirds, especially Procellariiformes such as petrels and shearwaters, are susceptible to light pollution. The Hauraki Gulf, a seabird hotspot located near Tāmaki Makaurau/Auckland, Aotearoa--New Zealand's largest urban city, with a considerable amount of light pollution and regularly documented events of seabird groundings. We aim to identify the characteristics of locations especially prone to seabird groundings. We used an online database of seabirds taken to a wildlife rescue facility by the public to map 3 years of seabird groundings and test for correlations between seabird groundings and the natural night sky brightness. We found that areas with lower amounts of natural night sky brightness and greater light pollution often had a higher number of seabirds grounded. Further, we identified important seasonal patterns and species differences in groundings. Such differences may be a by-product of species ecology, visual ecology and breeding locations, all of which may influence attraction to lights. In general, seabird groundings correlate with the brightness of the area and are species-specific. Groundings may not be indicative of human or seabird population abundance considering some areas have a lower human population with high light levels and had high amounts of seabird groundings. These findings can be applied worldwide to mitigate groundings by searching and targeting specific brightly lit anthropogenic structures. Those targeted structures and areas can then be the focus of light mitigation efforts to reduce seabird groundings. Finally, this study illustrates how a combination of community science, and a concern for seabirds grounded from light attraction, in addition to detailed animal welfare data and natural night sky brightness data can be a powerful, collaborative tool to aid global conservation efforts for highly-at-risk animals such as seabirds. [ABSTRACT FROM AUTHOR]

Garden bird sugar water feeding is increasingly popular worldwide, but little is known about its effects on bird health and associated diseases. There is a concern that feeding stations can accumulate pathogens and facilitate pathogen transmission between individuals, resulting in adverse effects on body condition of visiting birds. We tested the effects of sugar water feeding in urban New Zealand backyards by sampling target species for multiple infections and comparing bird body condition. For this, we compared backyards with and without sugar water feeders and again compared existing sugar water feeders with various sugar concentrations in two cities and in two seasons. Birds caught in gardens with sugar water feeders had poorer body condition; however, birds had better body condition in the city with the warmer climate (Auckland), during summer, and in gardens with high (≥20%) sugar concentration in sugar water feeders in winter. All screening tests for Chlamydia psittaci and Salmonella spp. returned negative results. Avian poxvirus prevalence in tauhou (Zosterops lateralis) was four times higher in the city with a warmer climate. The likelihood of lice infection in tauhou was lower in gardens with feeders, in the warmer city, in summer, and at feeders with higher sugar concentrations. In tui (Prosthemadera novaeseelandiae), the likelihood of lice infection decreased with an increase in sugar concentration. Coccidia infection was 4.25 times higher in tauhou in gardens with feeders. Despite the identified risks associated with sugar water feeding, there appear to be potential benefits for native nectarivorous birds, specifically in winter. [ABSTRACT FROM AUTHOR]

• Most animals tested show strong side preferences or behavioural lateralization. • We tested for limb preferences in a New Zealand rail that uses its feet to feed. • While some individuals showed preferences, there was no population side preference. • Individual that use their feet less frequently show a stronger apparent preference. • Our results contrast to most studies and expand the breadth of species tested. Many animals show evidence of cerebral lateralisation, i.e. morphological differences and functional specialisation in two separate hemispheres of the brain. Laterality in behaviour is commonly used as an indicator of cerebral lateralisation, as asymmetry in actions often mirrors asymmetry in the brain. It has been predicted that species that habitually use limbs to manipulate food or resources will develop strong limb preferences, and data in a limited set of taxa support this prediction. However, relatively few species have been studied, limiting our understanding of how taxonomically widespread such behavioural asymmetries might be, and thus how such preferences evolve. Here, we test for limb preference within a new taxon, the rails, using the pukeko (Porphyrio p. melanotus), a species that frequently uses its feet while feeding. We quantified foot-use of 359 individual pukeko and found that though some individuals show preferences, there was no overall side preference at the population level - roughly equal numbers of individuals showed a left preference, a right preference, or no preference, though we detected a weak preference in adults during long-use behaviours. We also found that the strength of side preference weakened with increased observations of foot-usage. Finally, though patterns were similar when looking at brief and longer foot uses, the within-individual relationships between preference in those contexts was only significant in birds that used their feet at least five times. Together these findings question whether habitual foot use will lead to side preference and suggest that the apparent wide-spread and prevalent nature of this pattern in current literature may be due to a publication bias rather than the general presence of a relationship. Studies that cover a great taxonomic spread are needed. [ABSTRACT FROM AUTHOR]

Despite extensive research on avian vocal learning, we still lack a general understanding of how and when this ability evolved in birds. As the closest living relatives of the earliest Passeriformes, the New Zealand wrens (Acanthisitti) hold a key phylogenetic position for furthering our understanding of the evolution of vocal learning because they share a common ancestor with two vocal learners: oscines and parrots. However, the vocal learning abilities of New Zealand wrens remain unexplored. Here, we test for the presence of prerequisite behaviors for vocal learning in one of the two extant species of New Zealand wrens, the rifleman (Acanthisitta chloris). We detect the presence of unique individual vocal signatures and show how these signatures are shaped by social proximity, as demonstrated by group vocal signatures and strong acoustic similarities among distantly related individuals in close social proximity. Further, we reveal that rifleman calls share similar phenotypic variance ratios to those previously reported in the learned vocalizations of the zebra finch, Taeniopygia guttata. Together these findings provide strong evidence that riflemen vocally converge, and though the mechanism still remains to be determined, they may also suggest that this vocal convergence is the result of rudimentary vocal learning abilities., (© 2024. The Author(s).)

Virus transmission between host species underpins disease emergence. Both host phylogenetic relatedness and aspects of their ecology, such as species interactions and predator-prey relationships, may govern rates and patterns of cross-species virus transmission and hence zoonotic risk. To address the impact of host phylogeny and ecology on virus diversity and evolution, we characterized the virome structure of a relatively isolated island ecological community in Fiordland, New Zealand, that are linked through a food web. We show that phylogenetic barriers that inhibited cross-species virus transmission occurred at the level of host phyla (between the Chordata, Arthropoda and Streptophyta) as well as at lower taxonomic levels. By contrast, host ecology, manifest as predator-prey interactions and diet, had a smaller influence on virome composition, especially at higher taxonomic levels. The virus-host community comprised a 'small world' network, in which hosts with a high diversity of viruses were more likely to acquire new viruses, and generalist viruses that infect multiple hosts were more likely to infect additional species compared to host specialist viruses. Such a highly connected ecological community increases the likelihood of cross-species virus transmission, particularly among closely related species, and suggests that host generalist viruses present the greatest risk of disease emergence., (© 2023. The Author(s).)