Journal of Avian Biology最新文献

{"title":"Habitat characteristics and the rate of decline in a threatened farmland bird, the ortolan bunting Emberiza hortulana","authors":"Sirke Piirainen,&nbsp;Tuomas Seimola,&nbsp;Andreas Lindén,&nbsp;Juha Tiainen,&nbsp;Markus Piha","doi":"10.1111/jav.03260","DOIUrl":"10.1111/jav.03260","url":null,"abstract":"<p>Farmland habitats witness steep declines in biodiversity. One rapidly declining farmland species is the ortolan bunting <i>Emberiza hortulana</i>. In Finland, a staggering 99% of the population has been lost during the past 30 years. Changes in the breeding habitats have been proposed as a reason for the decline, although hazards during migration and wintering may also play a role.</p><p>We gathered a 19-year data set of Finnish ortolan buntings and studied which spatial characteristics, habitat features, and climate factors might explain the population growth rate at the singing-group level. As explanatory variables we used region, density of small-scale structures, proportion of agricultural area in the landscape, diversity of crop types, proportion of bare ground, and temperature and precipitation of previous breeding season.</p><p>Higher population growth rates were associated with higher crop type diversity and higher proportion of bare ground. The mosaic of various crop plants and bare ground may provide a wider array of feeding, hiding and nesting places, and an easier access to food. Higher growth rates were also associated with landscapes dominated by interconnected agricultural land, which may reflect the species' sociability and avoidance of forested areas. The North Ostrobothnia region had higher growth rates compared to other regions.</p><p>We suggest that northern populations of ortolan bunting should be targeted for further studies on feeding and breeding ecology as well as for urgent conservation actions, such as increasing crop type diversity and bare ground.</p>","PeriodicalId":15278,"journal":{"name":"Journal of Avian Biology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jav.03260","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140836686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ecological correlates of alternative reproductive tactics: conspecific brood parasitism rates vary with nest predation and seasonal effects influenced by climate change","authors":"Susan B. McRae","doi":"10.1111/jav.03289","DOIUrl":"10.1111/jav.03289","url":null,"abstract":"<p>Ecological and social factors shape individual reproductive strategies. Climate change has wide-ranging effects on the timing of reproduction and availability of nesting sites for many birds. Ecological factors such as season length or predation rate could in turn affect the relative success rates of alternative reproductive tactics (ARTs). A new article by Pöysä (2024) featuring a long-term study of common goldeneyes <i>Bucephala clangula</i> highlights the role of climate change in altering rates of conspecific brood parasitism (CBP) by affecting nest initiation dates and season length. While some authors have emphasized the effects of spatial and temporal aggregation of nests in promoting tactics of reproductive interference, few studies have addressed the effects of environmental variables on rates of CBP and other ARTs. I review some of the evidence for a relationship between population-level nest predation rate and rates of CBP, principally in ducks and rails, and suggest a role for high rates of nest loss from all sources in the evolution of CBP and host responses. There is a need for further studies that examine environmental correlates of ARTs. Long-term studies have the highest potential to reveal how shifts in phenology and life history variables may respond to environmental perturbations. Comparative studies of similar species in remote geographic locations can add perspective of how different ecological variables affect the prevalence of ARTs.</p>","PeriodicalId":15278,"journal":{"name":"Journal of Avian Biology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jav.03289","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140836644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Good vibrations: remote-tactile foraging success of wading birds is positively affected by the water content of substrates they forage in","authors":"Carla J. du Toit,&nbsp;Anusuya Chinsamy,&nbsp;Susan J. Cunningham","doi":"10.1111/jav.03243","DOIUrl":"10.1111/jav.03243","url":null,"abstract":"<p>Some taxa of wading birds can locate buried prey by detecting vibratory cues in their foraging substrates while probe-foraging, using a sensory modality called ‘remote-touch'. As more saturated substrates transmit vibrations better, we predict that these birds can detect prey in wetter substrates more easily. We used sensory assays to test whether substrate water content affects the remote-touch foraging success rate of Hadeda ibises, <i>Bostrychia hagedash</i>. The birds were more successful at locating prey using vibratory cues than when relying on random direct contact with the beak alone. Their remote-touch foraging success rate was positively affected by increasing water contents of the soil, but water content had no effect on their direct contact foraging success (indicating this is not an artefact of ease of probing). This may partially explain the link between the range expansion of this species in southern Africa and increased soil irrigation, as it is easier for the birds to detect prey in wetter substrates. Thus, it is likely that the distribution of other remote-touch foraging birds is affected by substrate water content, and as many of these species are endangered and rely on sensitive wetland habitats, it is vital to understand their sensory requirements for foraging.</p>","PeriodicalId":15278,"journal":{"name":"Journal of Avian Biology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jav.03243","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140565310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strangers like me: birds respond equally to a familiar and an unfamiliar sentinel species' alarm calls, but respond less to non-core and non-sentinel's alarm calls","authors":"Jonah S. Dominguez,&nbsp;Morgan Bolger,&nbsp;Autumn Bush,&nbsp;Mark E. Hauber","doi":"10.1111/jav.03230","DOIUrl":"10.1111/jav.03230","url":null,"abstract":"<p>Alarm signals have evolved to communicate imminent threats to conspecifics but animals may also perceive other species' alarm displays to obtain adaptive information. In birds, mixed-species foraging flocks are often structured around a focal sentinel species, which produces reliable alarm calls that inform eavesdropping non-sentinel heterospecifics about predation risk. Ongoing work has revealed that several species can recognize the alarm calls of certain sentinel species even without prior encounters, including when these are from distant biogeographic regions. Similar work has yet to examine whether naive subjects' responses to unfamiliar sentinel alarm calls differ from responses to non-sentinel alarm calls. Here we played the alarm calls of three subtropical Asian bird species that participate in mixed species flocks, to temperate North American birds. Birds responded most to the alarm call of an allopatric core sentinel and a local sympatric sentinel control species, less so to an allopatric non-core sentinel, and least so to an allopatric non-sentinel and a negative control stimulus. These patterns provide evidence that broad phylogenetic and geographic recognition is a pertinent aspect of sentinel alarm calls in general.</p>","PeriodicalId":15278,"journal":{"name":"Journal of Avian Biology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jav.03230","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140565313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vocal dimorphism in Anna's hummingbirds","authors":"Sierra Ru-Yi Glassman,&nbsp;Adi Domer,&nbsp;Robert Dudley","doi":"10.1111/jav.03268","DOIUrl":"10.1111/jav.03268","url":null,"abstract":"<p>Sexual dimorphism in vocal signals is found across many bird species. By evaluating correlations among sex, behaviors, and vocalizations, the meaning and utility of sound production may be inferred. Anna's hummingbirds <i>Calypte anna</i> exhibit pronounced sexual dimorphism, with males being larger and having more vibrant coloration than females, but vocal dimorphism in the species is less studied. A common vocalization of Anna's hummingbirds is the chip note, which is produced by both sexes in a wide array of contexts. Here, we correlated temporal parameters of recorded chip notes with individual sex and behavioral contexts gathered from field observations. The production rate of chip notes differed significantly between male and female hummingbirds but did not vary much with behavioral context. Although Anna's hummingbirds produce chips across a broad spectrum of behaviors, dimorphic chip production may be especially important in territorial behavior.</p>","PeriodicalId":15278,"journal":{"name":"Journal of Avian Biology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jav.03268","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140565318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Young male blackcaps with blood parasite coinfections cope with oxidative stress favouring anthocyanin‐rich food during migratory fattening","authors":"Lucía Jiménez‐Gallardo, Jimena López‐Arrabé, Javier Pérez‐Tris, Carolina Remacha","doi":"10.1111/jav.03214","DOIUrl":"https://doi.org/10.1111/jav.03214","url":null,"abstract":"Parasites may alter host physiology, which may promote behavioural adaptations to counteract their effect. Adaptive feeding may help individuals to cope with infection, especially during physiologically demanding life stages. For instance, migrating birds need fuel for long‐distance flights and repair oxidative damage caused by intense aerobic exercise, and parasites may influence on how individuals balance these needs. Infected birds may face increased oxidative challenges, which could induce them to favour antioxidant defences over other needs, such as fattening. We tested whether migrating birds can adaptively choose food according to their needs, favouring dietary antioxidants to cope with oxidative stress caused by haemosporidian blood parasites during migration. During autumn migration, we mist‐netted young male Eurasian blackcaps <jats:italic>Sylvia atricapilla</jats:italic> stopping over in central Spain. We placed the birds in cages where they were offered fat and anthocyanin‐enriched food alternatives. We measured preference for each food offer. We tested their infections with haemosporidian parasites by PCR techniques and their parasitaemia by blood smear inspection. We also measured physiological variables that account for nutritional and oxidative status in red blood cells and plasma. We found that birds with multiple infections favoured anthocyanin‐enriched food controlling for an effect of body mass on food preference (lean blackcaps preferred anthocyanins, likely because they are urged to repair oxidative damage upon arrival on stopover with depleted energy reserves). Haemosporidian‐infected birds had a lower antioxidant capacity of plasma, although no effect of infections on oxidative damage was detected, and individuals with more oxidative damage preferred anthocyanin‐enriched food. Our results suggest that haemosporidian infections may increase individual antioxidant needs, which could affect migratory performance if the urge to find dietary antioxidants reduces the rate of fuel consumption.","PeriodicalId":15278,"journal":{"name":"Journal of Avian Biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140565163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using juvenile movements as a proxy for adult habitat and space use in long-lived territorial species: a case study on the golden eagle","authors":"Arzhela Hemery,&nbsp;Olivier Duriez,&nbsp;Christian Itty,&nbsp;Pierre-Yves Henry,&nbsp;Aurélien Besnard","doi":"10.1111/jav.03212","DOIUrl":"10.1111/jav.03212","url":null,"abstract":"<p>Effective conservation management of wildlife species depends on understanding their space and habitat use. Telemetry has become the primary source of data for information on how species use space and habitats. However, animals can be difficult to capture, leading to limited sample sizes and thus low quality inferences. As some individuals may be easier to capture than others, it may be tempting to use them to make inferences about the studied population as a whole. Juvenile birds, in contrast to adults, are easy to capture while they are still in the nest. However, there are few studies on when and how they might serve to obtain a representative characterization of the habitat or space use of adults. This study investigated this by using GPS-tracking data of 35 adult/juvenile dyads of golden eagles <i>Aquila chrysaetos</i>, with the juvenile and adult in a dyad sharing the same home-range. We assessed juvenile-to-adult home-range overlap and also compared their relative use of habitats within that space. We also analysed how these metrics evolved throughout the post-fledging dependence period (PFDP). During this period, juvenile-to-adult similarity was more than 80% for the entire home-range, whereas it was lower for the core area (approximately 60%). Habitat-use similarity was high, at approximately 90% for both the home-range and core area, both in land-cover and topography. The similarity increased following the improvement of juvenile flight skills over a period of two months, to the extent that two months after fledging and until the end of the PFDP, habitat and space use of juveniles can be used to infer the home-range and habitat requirements of adults. It would be valuable to study this ‘adult-by-juvenile replacement' approach in other species to determine whether it could be generalized, notably for species with a shorter dependence period or more complex social interactions.</p>","PeriodicalId":15278,"journal":{"name":"Journal of Avian Biology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jav.03212","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140565343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preening correlates with lower feather bacteria abundance but not feather coloration in a lek-breeding bird","authors":"Melanie R. Florkowski,&nbsp;Kirstin M. DeBlonk,&nbsp;Jessica L. Yorzinski","doi":"10.1111/jav.03209","DOIUrl":"10.1111/jav.03209","url":null,"abstract":"<p>Feathers are structures unique to birds that serve important functions such as flight, thermoregulation, and communication. Bacteria that live on the feathers, particularly ones that can break down keratin, have the potential to damage feathers and disrupt their use in communication. We predicted that birds could behaviorally manage their feather bacterial abundances by preening their feathers. We also predicted that individuals with lower feather bacterial abundances would have brighter and more colorful feathers. To test these predictions, we measured the amount of time individuals in a colony of captive Indian peafowl <i>Pavo cristatus</i> spent preening their feathers. We also collected feathers to determine bacteria abundance on the feather surface and to measure feather coloration. We found that birds had lower feather bacteria levels when they spent more time preening their own feathers, but only in female birds. We also found that bacteria abundances were not correlated with any feather color variables we measured. These results suggest that birds can manage feather bacterial abundances by preening but feather bacteria may not influence feather coloration in this species.</p>","PeriodicalId":15278,"journal":{"name":"Journal of Avian Biology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jav.03209","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140325315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nest predation and climate change as drivers of alternative reproductive tactics in a migratory species","authors":"Hannu Pöysä","doi":"10.1111/jav.03218","DOIUrl":"10.1111/jav.03218","url":null,"abstract":"<p>Alternative reproductive tactics enable individuals to choose a reproductive tactic relative to their status and prevailing environmental conditions in a way that increases their fitness. For example, females in many avian species show phenotypic plasticity and employ alternative reproductive tactics to cope with changes in predation risk and climate. Conspecific brood parasitism (CBP), in which females lay eggs in nests of conspecifics, is one example of such behaviour. It has been proposed that when prospects for successful nesting are low and/or costs of reproduction are high, females employ tactics of low effort such as non-breeding and parasitic laying. When environmental conditions are ideal and prospects for success high, females can increase their reproductive effort above typical nesting by laying parasitic eggs prior to initiating their own nest. Here, I used this flexible life-history strategy concept and long-term (1994‒2022) population level data of the common goldeneye <i>Bucephala clangula</i> to study how the rate of parasitic laying varies in relation to variation in nest predation risk and in the timing and length of the breeding season, the latter being measured by the timing of ice breakup. Nest predation rate in the previous year and timing of ice breakup interactively affected parasitic laying, the rate of parasitic laying being particularly high in years with late ice breakup and high nest predation rate in the previous year. Furthermore, the proportion of predated eggs was lower in parasitized nests than in non-parasitized nests, while the opposite was true for the proportion of eggs that failed in other way. As a consequence, the final number of young produced per nest was higher for parasitized nests. The findings of this study show that changes in environmental conditions affect the dynamics of alternative reproductive tactics in goldeneyes, with consequences to population level reproductive output.</p>","PeriodicalId":15278,"journal":{"name":"Journal of Avian Biology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jav.03218","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140311123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hematological parameters vary with life history stage in the pale-breasted thrush Turdus leucomelas","authors":"Ivan Celso C. Provinciato,&nbsp;Jenny Q. Ouyang,&nbsp;Ariovaldo P. Cruz-Neto","doi":"10.1111/jav.03242","DOIUrl":"10.1111/jav.03242","url":null,"abstract":"<p>The avian life cycle is composed by a progressive sequence of life history stages (LHS). Changes in energy expenditure and exposure to stressors at different LHS require corresponding changes in behavior, physiology, and morphology. Variation in hematological parameters, such hematocrit (Hct), hemoglobin (Hb), and heterophil to lymphocyte ratio (H/L ratio), can have permissive, stimulatory, and preparative actions to help maintain homeostasis through different LHS. Few studies have examined differences in these parameters among different LHS in free-living birds, with most of them restricted to temperate zones. We collected blood samples and measured hematological parameters every week for over a year from a population of a common resident bird species in southeastern Brazil, the pale-breasted thrush <i>Turdus leucomelas</i>. Hematocrit and hemoglobin concentration were highest during the onset of the reproduction and lowest during molt. Furthermore, H/L ratios were higher at the end of the reproduction, indicating that the breeding season could be the most stressful period of the year for this population of thrushes. There was no difference between sexes for any hematological parameter at any LHS. These results show that there is a permissive physiological effect for Hct and Hb to facilitate LHS transitions and that reproduction could be the most stressful event for this species. Lastly, these results mirror those from temperate species despite distinct environmental differences between these regions.</p>","PeriodicalId":15278,"journal":{"name":"Journal of Avian Biology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jav.03242","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140311333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}