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[Aim] Climate change causes shifts in species ranges globally. Terrestrial plant species often lag behind temperature shifts, and it is unclear to what extent animal-dispersed plants can track climate change. Here, we estimate the ability of bird-dispersed plant species to track future temperature change on a tropical mountain., [Location] Tropical elevational gradient (500–3500 m.a.s.l.) in the Manú biosphere reserve, Peru. [Time period] From 1960–1990 to 2061–2080. [Taxa] Fleshy-fruited plants and avian frugivores. [Methods] Using simulations based on the functional traits of avian frugivores and fruiting plants, we quantified the number of long-distance dispersal (LDD) events that woody plant species would require to track projected temperature shifts on a tropical mountain by the year 2070 under different greenhouse gas emission scenarios [representative concentration pathway (RCP) 2.6, 4.5 and 8.5]. We applied this approach to 343 bird-dispersed woody plant species. [Results] Our simulations revealed that bird-dispersed plants differed in their climate-tracking ability, with large-fruited and canopy plants exhibiting a higher climate-tracking ability. Our simulations also suggested that even under scenarios of strong and intermediate mitigation of greenhouse gas emissions (RCP 2.6 and 4.5), sufficient upslope dispersal would require several LDD events by 2070, which is unlikely for the majority of woody plant species. Furthermore, the ability of plant species to track future changes in temperature increased in simulations with a low degree of trait matching between plants and birds, suggesting that plants in generalized seed-dispersal systems might be more resilient to climate change. [Main conclusion] Our study illustrates how the functional traits of plants and animals can inform predictive models of species dispersal and range shifts under climate change and suggests that the biodiversity of tropical mountain ecosystems is highly vulnerable to future warming. The increasing availability of functional trait data for plants and animals globally will allow parameterization of similar models for many other seed-dispersal systems., Fieldwork at Manú was conducted under the permits 041-2010-AG-DGFFSDGEFFS, 008-2011-AG-DGFFS-DGEFFS, 01-C/C-2010SERNANP-JPNM and 01-2011-SERNANP-PNM-JEF and supported by a scholarship from the German Academic Exchange Service to D.M.D. D.M.D. acknowledges funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant number 787638) and the Swiss National Science Foundation (grant number 173342), both awarded to C. H. Graham. W.D.K. acknowledges a Global Ecology grant from the University of Amsterdam Faculty Research Cluster. I.D. was funded by the Alexander von Humboldt Foundation and is now supported by the Balearic Government. S.A.F. was funded by the German Research Foundation (DFG; FR 3246/2-2) and the Leibniz Competition of the Leibniz Association (P52/2017).

For many species, breeding performance increases through early adulthood followed by declines later in life. Although patterns of age-specific decline have been shown to vary between individuals, the factors that lead to this individual variation in the intensity of reproductive senescence are yet to be fully understood. We investigated whether early-life social status influenced age-related trends in the breeding performance of male Canada jays (Perisoreus canadensis), year-round residents of North America's boreal and sub-alpine forests. Shortly after young become nutritionally independent, intra-brood dominance struggles lead to one juvenile (Dominant Juvenile) remaining on the natal territory after expelling its subordinate siblings (Ejectees). First, we show via radio tracking that in our declining range-edge population Ejectees either join an unrelated pair (67%), form a breeding pair with another bird (28%) or occupy a territory alone (5%). Second, using 39 years of breeding data, we demonstrate that Ejectee males advanced laying dates and increased the annual number of nestlings until 6 years of age before declining, whereas Dominant Juvenile males advanced laying dates until 11 years and increased annual number of nestlings until 12 years of age before declining. This study documents clear variation in ageing patterns between dominant and expelled young, with implications for the role of early-life experiences and phenotypic quality in determining patterns of ageing.

Domestic cats Felis catus have a complex and contentious history. They fill multiple societal roles (e.g. as pest controllers and companion animals), which has led to a variety of animal welfare, conservation, and human health concerns. Popular press articles play an important role in how people learn about key issues surrounding cats, but they may present some issues more frequently than other issues. We conducted a global media content analysis of 796 articles in the English‐language media from 1990 to 2018 on issues related to free‐roaming cats, such as their environmental impacts, the threats and welfare issues cats face, and how they are managed. We aimed to determine whether non‐experts learning about the issues around free‐roaming cats exclusively from the popular press would be exposed to multiple stakeholder views or opinions. Over 95% of articles analysed were from North America. Most of the people interviewed in the popular press were from non‐governmental organizations, mainly from cat welfare or cat rights groups (which are often focused on only one side of the issue). Researchers, shelter organizations, veterinarians, and groups that have different opinions than cat rights or welfare organizations on how to resolve issues surrounding free‐roaming cats were rarely interviewed by the popular press. Most articles focused on cat welfare issues and the management strategies of euthanasia or trap–neuter–release (TNR), whereas less than one‐third of the articles acknowledged that cats have any impact on wildlife or the broader environment. We found that the popular press often presented an oversimplified picture of issues related to free‐roaming cats and provided unbalanced coverage. We also show evidence of framing by the popular press, including mainly presenting the viewpoints and perspectives from animal welfare and rights groups, focusing on TNR or euthanasia as the only viable cat management strategies when many alternatives exist and often have greater support from experts, and discussing the impacts of cats on birds and small mammals but not reptiles or amphibians. A free Plain Language Summary can be found within the Supporting Information of this article.

Tobias, Joseph A., Sheard, Catherine, Pigot, Alex L., Devenish, Adam J. M., Yang, Jingyi, Sayol, Ferran, Neate‐Clegg, Montague H. C., Alioravainen, Nico, Weeks, Thomas L., Barber, Robert A., Walkden, Patrick A., MacGregor, Hannah E. A., Jones, Samuel E. I., Vincent, Claire, Phillips, Anna G., Marples, Nicola M., Montaño‐Centellas, Flavia A., Leandro‐Silva, Victor, Claramunt, Santiago, Darski, Bianca, Freeman, Benjamin G., Bregman, Tom P., Cooney, Christopher R., Hughes, Emma C., Capp, Elliot J. R., Varley, Zoë K., Friedman, Nicholas R., Korntheuer, Heiko, Corrales‐Vargas, Andrea, Trisos, Christopher H., Weeks, Brian C., Hanz, Dagmar M., Töpfer, Till, Bravo, Gustavo A., Remeš, Vladimír, Nowak, Larissa, Carneiro, Lincoln S., Moncada R., Amilkar J., Matysioková, Beata, Baldassarre, Daniel T., Martínez‐Salinas, Alejandra, Wolfe, Jared D., Chapman, Philip M., Daly, Benjamin G., Sorensen, Marjorie C., Neu, Alexander, Ford, Michael A., Mayhew, Rebekah J., Fabio Silveira, Luis, Kelly, David J., Annorbah, Nathaniel N. D., Pollock, Henry S., Grabowska‐Zhang, Ada M., McEntee, Jay P., Carlos T. Gonzalez, Juan, Meneses, Camila G., Muñoz, Marcia C., Powell, Luke L., Jamie, Gabriel A., Matthews, Thomas J., Johnson, Oscar, Brito, Guilherme R. R., Zyskowski, Kristof, Crates, Ross, Harvey, Michael G., Jurado Zevallos, Maura, Hosner, Peter A., Bradfer‐Lawrence, Tom, Maley, James M., Stiles, F. Gary, Lima, Hevana S., Provost, Kaiya L., Chibesa, Moses, Mashao, Mmatjie, Howard, Jeffrey T., Mlamba, Edson, Chua, Marcus A. H., Li, Bicheng, Gómez, M. Isabel, García, Natalia C., Päckert, Martin, Fuchs, Jérôme, Ali, Jarome R., Derryberry, Elizabeth P., Carlson, Monica L., Urriza, Rolly C., Brzeski, Kristin E., Prawiradilaga, Dewi M., Rayner, Matt J., Miller, Eliot T., Bowie, Rauri C. K., Lafontaine, René‐Marie, Scofield, R. Paul, Lou, Yingqiang, Somarathna, Lankani, Lepage, Denis, Illif, Marshall, Neuschulz, Eike Lena, Templin, Mathias, Dehling, D. Matthias, Cooper, Jacob C., Pauwels, Olivier S. G., Analuddin, Kangkuso, Fjeldså, Jon, Seddon, Nathalie, Sweet, Paul R., DeClerck, Fabrice A. J., Naka, Luciano N., Brawn, Jeffrey D., Aleixo, Alexandre, Böhning‐Gaese, Katrin, Rahbek, Carsten, Fritz, Susanne A., Thomas, Gavin H., Schleuning, Matthias (2022): AVONET: morphological, ecological and geographical data for all birds. Ecology Letters 25 (3): 581-597, DOI: 10.1111/ele.13898, URL: http://dx.doi.org/10.1111/ele.13898

Network approaches provide insight into the complex web of interspecific interactions that structure ecological communities. However, because data on the functional outcomes of ecological networks are very rarely available, the effect of network structure on ecosystem functions, such as seed dispersal, is largely unknown. Here, we develop a new approach that is able to link interaction networks to a trait‐based seed–dispersal model to estimate community‐wide seed dispersal distances. We simulated networks, using a niche model based on size‐matching between plants and birds, that varied in the degree of niche partitioning, i.e. the overlap in interaction partners between coexisting species. We found that community‐wide dispersal distances were longest when networks had low degrees of niche partitioning. We further found that dispersal distances of plant species with small fruits peaked in models without niche partitioning, whereas dispersal distances of medium and large‐fruited plants peaked at low degrees of niche partitioning. Our simulations demonstrate that the degree of niche partitioning between species is an important determinant of the ecological functions derived from ecological networks and that simulation approaches can provide new insights into the relationship between the structural and functional components of ecological networks.

Migration can influence host–parasite dynamics in animals by increasing exposure to parasites, by reducing the energy available for immune defense, or by culling of infected individuals. These mechanisms have been demonstrated in several comparative analyses; however, few studies have investigated whether conspecific variation in migration distance may also be related to infection risk. Here, we ask whether autumn migration distance, inferred from stable hydrogen isotope analysis of summer‐grown feathers (δ 2Hf) in Europe, correlates with blood parasite prevalence and intensity of infection for willow warblers (Phylloscopus trochilus) wintering in Zambia. We also investigated whether infection was correlated with individual condition (assessed via corticosterone, scaled mass index, and feather quality). We found that 43% of birds were infected with Haemoproteus palloris (lineage WW1). Using generalized linear models, we found no relationship between migration distance and either Haemoproteus infection prevalence or intensity. There was spatial variation in breeding ground origins of infected versus noninfected birds, with infected birds originating from more northern sites than noninfected birds, but this difference translated into only slightly longer estimated migration distances (~214 km) for infected birds. We found no relationship between body condition indices and Haemoproteus infection prevalence or intensity. Our results do not support any of the proposed mechanisms for migration effects on host–parasite dynamics and cautiously suggest that other factors may be more important for determining individual susceptibility to disease in migratory bird species.

Downsizing of animal communities due to defaunation is prevalent in many ecosystems. Yet, we know little about its consequences for ecosystem functions such as seed dispersal. Here, we use eight seed-dispersal networks sampled across the Andes and simulate how downsizing of avian frugivores impacts structural network robustness and seed dispersal. We use a trait-based modeling framework to quantify the consequences of downsizing—relative to random extinctions—for the number of interactions and secondary plant extinctions (as measures of structural robustness) and for long-distance seed dispersal (as a measure of ecosystem function). We find that downsizing leads to stronger functional than structural losses. For instance, 10% size-structured loss of bird species results in almost 40% decline of long-distance seed dispersal, but in less than 10% of structural loss. Our simulations reveal that measures of the structural robustness of ecological networks underestimate the consequences of animal extinction and downsizing for ecosystem functioning., Species loss from ecological networks can impair network stability and ecosystem function. Here the authors simulate animal extinctions in interaction networks between plants and avian frugivores, showing that frugivore extinctions have comparatively weak effects on network structure, but strongly reduce seed-dispersal distance.

Objective To determine the epidemiology and risk factors of childhood injuries in Ismailia governorate Egypt. Methods This is the Egyptian chapter of the Global Childhood Unintentional Injury Surveillance study, which employed quota sampling of children 0–11 years old presenting to the Emergency Department. This surveillance was conducted in the University Hospital of Suez Canal University Egypt, for selected months in 2007. Children with an unintentional injury of both genders were enrolled in the study. Results Out of a total of 551 cases, 361 were males (66%) and 478 (34%) females. The most common external causes of injuries were falls (60%), road traffic injuries (15%), burns (7%), poisoning (3%) and near drowning/drowning (2%). The most common sustained injuries were fractures (17%), cuts or open wounds (15%), sprains (14%) and burns (9%). The majority of patients were treated and discharged home without disability (67%), while 7.8% had long-term temporary disability that lasted for more than 6 weeks and more than 1% sustained permanent disability. There were five deaths (1% proportionate mortality), all were due to falls. Few families recounted using seatbelts (2%), car air bags (0.5%), helmets (1%), child restraint seats (1%). The majority of children received care via government insurance. Conclusions The burden of childhood injuries on the university hospital in Egypt is substantial. Ongoing child injury surveillance using systematic approaches is required to identify the epidemiology of injuries, their risk factors and plan for timely interventions.

Plant–animal interactions are fundamentally important in ecosystems, but have often been ignored by studies of climate-change impacts on biodiversity. Here, we present a trait-based framework for predicting the responses of interacting plants and animals to climate change. We distinguish three pathways along which climate change can impact interacting species in ecological communities: (i) spatial and temporal mismatches in the occurrence and abundance of species, (ii) the formation of novel interactions and secondary extinctions, and (iii) alterations of the dispersal ability of plants. These pathways are mediated by three kinds of functional traits: response traits, matching traits, and dispersal traits. We propose that incorporating these traits into predictive models will improve assessments of the responses of interacting species to climate change.

Malaria parasites can have strong effects on the population dynamics and evolution of migratory bird species. In many species, parasite transmission occurs on the wintering grounds, but studies to determine the consequences of infection have taken place during the breeding season, when malaria parasites circulate at chronic levels. We examined the predictors of malarial infections for great reed warblers during the northern winter in Africa, where active parasite transmission is thought to occur and naive individuals experience acute infections. Counter to expectations, we found that winter infection intensities were lower than those encountered on the breeding grounds. One potential explanation is that reduced immune function during breeding allows parasites to persist at higher chronic intensities. We found no relationships between the incidence or intensity of infection on condition (as measured by scaled mass index, plasma metabolites, and feather corticosterone), spring migration departure dates, or home range sizes. We also tested a prediction of the Hamilton–Zuk hypothesis and found that male ornament (song) quality was unrelated to parasitic infection status. Overall, our results provide the first evidence that long-distance migrants captured on their wintering grounds are in the chronic stage of infection, and suggest that winter studies may fare no better than breeding studies at determining the costs of acute malarial infection for great reed warblers.

Animal sexual signals have been well studied in the context of mate attraction, but less attention has focused on the function of signals produced at other times of the year. Despite decades of research on bird song, we still do not know why many migratory songbirds also sing intensely on their wintering grounds. It has long been assumed that winter song is used to defend individual feeding territories; however, this assumption has never been tested. I studied willow warblers (Phylloscopus trochilus) that regularly sing on their African wintering grounds to test this supposition using a combination of behavioral experiments and radio telemetry. Contrary to expectations for individual territory defense, I found that individuals foraged in conspecific groups with fluid group membership, moved itinerantly from site to site rather than remaining in stable territories, and were highly aggressive toward model presentations combined with song playback, but in groups rather than individually. These results suggest a puzzling alternative function for winter song—singing for group territory defense—where territories are short term and group membership is not fixed. This work highlights the scarcity of our knowledge on the nonbreeding behavior of Palearctic–African songbirds and the unexpected complexity of avian social organization during this period of the annual cycle.

Many long-distance migratory birds sing extensively on their tropical African wintering grounds, but the function of this costly behavior remains unknown. In this study, we carry out a first empirical test of three competing hypotheses, combining a field study of great reed warblers (Acrocephalus arundinaceus) wintering in Africa with a comparative analysis across Palearctic-African migratory songbird species. We asked whether winter song (i) functions to defend nonbreeding territories, (ii) functions as practice to improve complex songs for subsequent breeding, or (iii) is a nonadaptive consequence of elevated testosterone carryover. We found support for neither the long-assumed territory-defense hypothesis (great reed warblers had widely overlapping home ranges and showed no conspecific aggression) nor the testosterone-carryover hypothesis (winter singing in great reed warblers was unrelated to plasma testosterone concentration). Instead, we found strongest support for the song-improvement hypothesis, since great reed warblers sang a mate attraction song type rather than a territorial song type in Africa, and species that sing most intensely in Africa were those in which sexual selection acts most strongly on song characteristics; they had more complex songs and were more likely to be sexually monochromatic. This study underlines how sexual selection can have far-reaching effects on animal ecology throughout the annual cycle.

Understanding the mechanisms that influence variation in sexually selected ornaments in seabirds has been challenging owing to the difficulty of capturing and sampling individuals outside of the breeding period when ornaments are usually grown. Stable carbon (d 13 C) and nitrogen (d 15 N) isotopes were used to examine the influence of pre-breeding diet composition on ornament size in the Rhinoceros Auklet Cerorhinca monocerata ,a socially monogamous seabird that breeds in the North Pacific. We analysed stable isotopes in adult feathers grown during the pre-alternate moult, which allowed us to infer diet composition during the pre-breeding (February‐March) period. Females that fed more on inshore fish had larger horns than females that fed more on euphausiids (also known as krill; Euphausiacea). Body size was a stronger predictor of horn height in males than females, suggesting that ornaments may serve as different signals for each sex. This study provides evidence that diet during the pre-breeding period can influence ornament size and emphasizes the importance of understanding individual ecology throughout the annual cycle for determining the factors that influence mate choice and fitness.

1. Understanding the interactions between different periods of the annual cycle in migratory animals has been constrained by our inability to track individuals across seasons. In seabirds, virtually nothing is known about how diet quality during the non-breeding period, away from the breeding grounds, might influence subsequent reproductive success. 2. We used stable nitrogen (delta(15)N) and carbon (delta(13)C) isotopes to evaluate the effects of non-breeding diet quality on the timing of breeding and egg size in a population of Cassin's auklets (Ptychoramphus aleuticus) breeding on Triangle Island, British Columbia. Adult feathers are grown during two different periods of the annual cycle, which allowed us to estimate diet quality from the previous fall (October-November) and pre-breeding (February-March) period. 3. We found that the estimated proportion of energetically superior copepods (Neocalanus spp.) in the pre-breeding diet tended to be higher in females that bred earlier and laid larger eggs, whereas energetically poor juvenile rockfish (Sebastes spp.) were dominant in the pre-breeding diets of females that bred later and laid smaller eggs. We detected no effect of fall diet quality on breeding date or egg size, and no effect of pre-breeding diet quality on breeding date in males. 4. Pre-breeding diet quality was not related to body condition measured 1-2 days after laying, which suggests that females may need to attain a threshold condition before they initiate breeding and successfully rear young. 5. Our results suggest that changes in climatic conditions during the pre-breeding period may have severe consequences for reproductive success by influencing breeding date and egg size. Our work emphasizes the importance of determining how events are linked throughout the annual cycle for understanding the fitness and population dynamics of migratory animals.

Understanding spatial connections between breeding and wintering populations is critical for developing sound conservation plans in migratory animals. However, for long-distance migratory songbird species wintering in sub-Saharan Africa, many of which are in a state of population decline, information on migratory connectivity is especially lacking. We used mitochondrial DNA data from wintering populations of the Great Reed Warbler (Acrocephalus arundinaceus) in western (Nigeria), southern (Botswana and Zambia) and eastern (Kenya) Africa, as well as from several Eurasian breeding populations, to compare genetic differentiation and haplotype sharing between non-breeding and breeding populations. We found that the population in Nigeria had the best genetic match to breeding populations in West and Central Europe. In contrast, Botswana matched with West, Central and East Europe, and Zambia with Central and East Europe and the Middle East. Finally, Kenya showed the most distinct connectivity pattern of the four analysed populations and matched with East Europe and, in particular, to the Middle East. Our results indicate clear but weak migratory connectivity in Great Reed Warblers, a pattern that should be considered in conservation strategies of Palearctic African migratory passerines.Keywords: bird, connectivity, distribution range, genetic similarity, migration, mitochondria, population differentiation