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Publication Metadata only A global analysis of the determinants of alien geographical range size in birds(Wiley, 2016) Dyer, Ellie E.; Franks, Victoria; Cassey, Phillip; Collen, Ben; Cope, Robert C.; Jones, Kate E.; Blackburn, Tim M.; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589Aim Determining the causes of range size variation in the distributions of alien species is important for understanding the spread of invasive species. Factors influencing alien range size have been explored for some species at a regional level, but to date there has been no global analysis of an entire class. Here, we present such an analysis for birds, testing for the effects of introduction event, location and species-level variables on alien range sizes. Location Global. Methods We used a novel dataset on the global distributions of alien bird species to test for relationships between alien range size and colonization pressure, residence time, extent of the global climatic niche, native range size, body mass and specialization, using a statistical approach based on phylogenetic generalized least squares models. We performed this analysis globally, and for separate biogeographical realms. Results Approximately half of the variation in alien bird range size is explained by colonization pressure in univariate analysis. We identified consistent effects of higher colonization pressure at global and realm levels, as well as support for effects of native range size and residence time. We found less support for effects of body mass, specialization or extent of the global climatic niche on alien range size. Main conclusions Alien bird range sizes are generally small relative to their native range sizes, and many are continuing to expand. Nevertheless, current variation is predictable, most strongly by the event-level factor of colonization pressure. Whether a species is widespread is a better predictor of alien range size than whether a species could be widespread (estimated by global climatic niche extent), while we also find effects of residence time on alien range size. These relationships may help to identify those alien species that are more likely to spread and hence have greater environmental and economic impacts where they have been introduced.Publication Metadata only Author Correction: urbanization, climate and species traits shape mammal communities from local to continental scales(Nature Portfolio, 2024) Haight JD, Hall SJ, Fidino M, Adalsteinsson SA, Ahlers AA, Angstmann J, Anthonysamy WJB, Biro E, Collins MK, Dugelby B, Gallo T, Green AM, Hartley L, Jordan MJ, Kay CAM, Lehrer EW, Long RA, MacDougall B, Magle SB, Minier DE, Mowry C, Murray M, Nininger K, Pendergast ME, Remine KR, Ryan T, Salsbury C, Sander HA, Schell CJ, Shier CJ, Simon KC, St Clair CC, Stankowich T, Stevenson CJ, Wayne L, Will D, Williamson J, Wilson L, Zellmer AJ, Lewis JS.; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Department of Molecular Biology and Genetics; College of SciencesN/APublication Metadata only Avian responses to selective logging shaped by species traits and logging practices(The Royal Society, 2015) Burivalova, Zuzana; Lee, Tien Ming; Giam, Xingli; Wilcove, David S.; Koh, Lian Pin; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589Selective logging is one of the most common forms of forest use in the tropics. Although the effects of selective logging on biodiversity have been widely studied, there is little agreement on the relationship between life-history traits and tolerance to logging. In this study, we assessed how species traits and logging practices combine to determine species responses to selective logging, based on over 4000 observations of the responses of nearly 1000 bird species to selective logging across the tropics. Our analysis shows that species traits, such as feeding group and body mass, and logging practices, such as time since logging and logging intensity, interact to influence a species' response to logging. Frugivores and insectivores were most adversely affected by logging and declined further with increasing logging intensity. Nectarivores and granivores responded positively to selective logging for the first two decades, after which their abundances decrease below pre-logging levels. Larger species of omnivores and granivores responded more positively to selective logging than smaller species from either feeding group, whereas this effect of body size was reversed for carnivores, herbivores, frugivores and insectivores. Most importantly, species most negatively impacted by selective logging had not recovered approximately 40 years after logging cessation. We conclude that selective timber harvest has the potential to cause large and long-lasting changes in avian biodiversity. However, our results suggest that the impacts can be mitigated to a certain extent through specific forest management strategies such as Llengthening the rotation cycle and implementing reduced impact logging.Publication Open Access Counter-interception and counter-exploitation features of noise radar technology(Multidisciplinary Digital Publishing Institute (MDPI), 2021) Galati, Gaspare; Pavan, Gabriele; Wasserzier, Christoph; Department of Electrical and Electronics Engineering; Savcı, Kubilay; Department of Electrical and Electronics Engineering; Graduate School of Sciences and EngineeringIn defense applications, the main features of radars are the Low Probability of Intercept (LPI) and the Low Probability of Exploitation (LPE). The counterpart uses more and more capable intercept receivers and signal processors thanks to the ongoing technological progress. Noise Radar Technology (NRT) is probably a very effective answer to the increasing demand for operational LPI/LPE radars. The design and selection of the radiated waveforms, while respecting the prescribed spectrum occupancy, has to comply with the contrasting requirements of LPI/LPE and of a favorable shape of the ambiguity function. Information theory seems to be a “technologically agnostic” tool to attempt to quantify the LPI/LPE capability of noise waveforms with little, or absent, a priori knowledge of the means and the strategies used by the counterpart. An information theoretical analysis can lead to practical results in the design and selection of NRT waveforms.Publication Metadata only Determinants of data deficiency in the impacts of alien bird species(Wiley, 2018) Evans, Thomas; Pigot, Alex; Kumschick, Sabrina; Blackburn, Tim M.; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589To identify the factors that influence the availability of data on the negative impacts of alien bird species, in order to understand why more than 70% are currently classified as Data Deficient (DD) by the Environmental Impact Classification of Alien Taxa (EICAT) protocol. Information on factors hypothesised to influence the availability of impact data were collated for 344 alien bird species (107 with impact data and 237 DD). These data were analysed using mixed effects models accounting for phylogenetic non-independence of species (MCMCglmm). Data deficiency in the negative impacts of alien birds is not randomly distributed. Residence time, relative brain size and alien range size were found to be strongly related to the availability of data on impacts. The availability of data on the negative impacts of alien birds is mainly influenced by the spatial and temporal extents of their alien ranges. The results of this study suggest that the impacts of some DD alien birds are likely to be minor (e.g. species with comparatively long residence times as aliens, such as the common waxbill Estrilda astrild and the Java sparrow Padda oryzivora). However, the results also suggest that some DD alien birds may have damaging impacts (e.g. species from orders of alien birds known for their impacts to biodiversity but with comparatively small alien ranges, such as the New Caledonian crow Corvus moneduloides). This implies that at least some DD alien birds may have impacts that are being overlooked. Studies examining the traits that influence the severity of alien bird impacts are needed to help to predict which DD species are more likely to impact upon biodiversity.Publication Metadata only Exploration behavior differs between Darwin's finch species and predicts territory defense and hatching success(Springer, 2024) Katsis, Andrew C.; Colombelli-Negrel, Diane; Common, Lauren K.; Garcia-Loor, Jefferson; Kleindorfer, Sonia; Department of Psychology; Akçay, Çağlar; Department of Psychology; College of Social Sciences and HumanitiesDarwin's finch species in the Galapagos Islands are famously distinguished by their morphology but less attention has been given to behavioral differences between species. In this study, we compared behavior between four Darwin's finch species on Floreana Island: small ground finch (Geospiza fuliginosa), medium ground finch (G. fortis), small tree finch (Camarhynchus parvulus), and medium tree finch (C. pauper). After capturing birds using mist-nets, we measured three behavioral traits: (1) boldness during human handling, (2) exploration in a novel environment, and (3) aggressiveness towards their mirror image. First, we found that ground finches were bolder and more exploratory than tree finches, consistent with their distinct ecological niches on Floreana Island and with the theoretical prediction that diet generalists should be less wary of novelty. Second, we tested the ecological validity of these behavioral variables at the individual level by relating them to territory defense behavior and breeding success. We found that males that were more exploratory in the novel environment also reacted more aggressively to a simulated territory intruder and showed lower offspring hatching success during the breeding season. Hence, our findings support previous work showing behavioral differences between Darwin's finch species and also suggest pathways by which behavioral differences among individuals might influence fitness. Significance statement Closely-related species that overlap in their geographical range may differ in their morphology and/or behavior, allowing them to occupy different ecological niches. In this study, we explored behavioral differences between four Darwin's finch species on Floreana Island in the Galapagos Archipelago. We found clear interspecies differences in behavior, with the ground finches struggling more often during handling (boldness) and visiting more sectors in a novel environment (exploration) compared to the tree finches. After birds were released, we continued to observe a subset of male finches in the wild. An individual's exploration behavior significantly predicted both its aggressive response to a territory intruder (simulated using song playback) and offspring hatching success during the breeding season. This suggests that individual differences in exploration behavior can potentially be used as a proxy for territorial behavior in the wild and may also predict fitness outcomes.Publication Metadata only Generation lengths of the world's birds and their implications for extinction risk(Wiley, 2020) Bird, Jeremy P.; Martin, Robert; Akcakaya, H. Resit; Gilroy, James; Burfield, Ian J.; Garnett, Stephen T.; Symes, Andy; Taylor, Joseph; Butchart, Stuart H. M.; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; N/A; 327589Birds have been comprehensively assessed on the International Union for Conservation of Nature (IUCN) Red List more times than any other taxonomic group. However, to date, generation lengths have not been systematically estimated to scale population trends when undertaking assessments, as required by the criteria of the IUCN Red List. We compiled information from major databases of published life-history and trait data for all birds and imputed missing life-history data as a function of species traits with generalized linear mixed models. Generation lengths were derived for all species, based on our modeled values of age at first breeding, maximum longevity, and annual adult survival. The resulting generation lengths varied from 1.42 to 27.87 years (median 2.99). Most species (61%) had generation lengths <3.33 years, meaning that the period of 3 generations-over which population declines are assessed under criterion A-was <10 years, which is the value used for IUCN Red List assessments of species with short generation times. For these species, our trait-informed estimates of generation length suggested that 10 years is a robust precautionary value for threat assessment. In other cases, however, for whole families, genera, or individual species, generation length had a substantial impact on their estimated extinction risk, resulting in higher extinction risk in long-lived species than in short-lived species. Although our approach effectively addressed data gaps, generation lengths for some species may have been underestimated due to a paucity of life-history data. Overall, our results will strengthen future extinction-risk assessments and augment key databases of avian life-history and trait data.Publication Metadata only Global effects of land use on biodiversity differ among functional groups(Wiley, 2020) Newbold, Tim; Bentley, Laura F.; Hill, Samantha L. L.; Edgar, Melanie J.; Horton, Matthew; Su, Geoffrey; Collen, Ben; Purvis, Andy; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589Human land use has caused substantial declines in global species richness. Evidence from different taxonomic groups and geographic regions suggests that land use does not equally impact all organisms within terrestrial ecological communities, and that different functional groups of species may respond differently. In particular, we expect large carnivores to decline more in disturbed land uses than other animal groups. We present the first global synthesis of responses to land use across functional groups using data from a wide set of animal species, including herbivores, omnivores, carnivores, fungivores and detritivores; and ranging in body mass from 2 x 10(-6) g (an oribatid mite) to 3,825 kg (the African elephant). We show that the abundance of large endotherms, small ectotherms, carnivores and fungivores (although in the last case, not significantly) are reduced disproportionately in human land uses compared with the abundance of other functional groups. The results, suggesting that certain functional groups are consistently favoured over others in land used by humans, imply a substantial restructuring of ecological communities. Given that different functional groups make unique contributions to ecological processes, it is likely that there will be substantial impacts on the functioning of ecosystems. A free Plain Language Summary can be found within the Supporting Information of this article.Publication Open Access How COVID-19 financially hit urban refugees: evidence from mixed-method research with citizens and Syrian refugees in Turkey(Wiley, 2021) Kirişçioğlu, Eda; Department of International Relations; Elçi, Ezgi; Faculty Member; Department of International Relations; College of Administrative Sciences and Economics; Graduate School of Social Sciences and Humanities; 238439; N/APeering through a lens of disasters and inequalities, this article measures the financial impacts of Covid-19 on citizens and refugee communities in Turkey during a relatively early phase of the global pandemic. Our data comes from an online survey (N = 1749) conducted simultaneously with Turkish citizens and Syrian refugees living in Turkey, followed by in-depth online interviews with Syrian refugees. Our findings indicate that the initial Covid-19 measures had a higher financial impact on Syrians than on citizens when controlled for employment, wealth, and education, among other variables. In line with the literature, our research confirms that disasters' socio-economic effects disproportionally burden minority communities. We additionally discuss how Covid-19 measures have significantly accelerated effects on refugees compared to the local population, mainly due to the structural and policy context within which forcibly displaced Syrians have been received in Turkey.Publication Metadata only Human-brown bear conflicts in Türkiye are driven by increased human presence around protected areas(ELSEVIER, 2024) Kusak, Josip; Department of Molecular Biology and Genetics; Sıkdokur, Ercan; Çeltik, Elif; Aytekin, M. Çisel Kemahlı; Sağlam, İsmail Kudret; Şekercioğlu, Çağan Hakkı; Department of Molecular Biology and Genetics; College of Sciences; Graduate School of Sciences and EngineeringHuman-wildlife conflict has become a major challenge to conservation efforts around the world. Brown bears (Ursus arctos), which globally suffer from reduced habitat suitability and quality, frequently conflict with humans. These animals need large home ranges to fulfil their habitat requirements. When space and food are restricted, brown bears frequently shift towards human-dominated landscapes that offer reliable food sources. T & uuml;rkiye, a country with predominantly human-dominated landscapes, experiences frequent human-brown bear conflicts (HBCs). However, there has been no formal analysis of the nature and scope of these conflicts at the country level. Using HBC data from 2017 to 2022, we analyzed the spatial and temporal dynamics of HBC events in T & uuml;rkiye , constructing a risk map based on anthropogenic variables and geographic profiling to identify the driving forces. HBC events did not show any annual or seasonal trends but displayed considerable variation across biogeographic regions, with the highest incidence concentrated along the Black Sea coast and in Eastern Anatolia. Sixty percent of all conflicts were due to bear foraging behavior in or near human settlements while 12 % were the result of human activity in forests, with 57% of all conflict events resulting in direct injury to either humans or bears. Our analyses showed proximity to villages, protected areas, farmland, and the human footprint to be pivotal factors influencing conflict risk. Approximately 21% of the country's territory is susceptible to human-bear conflicts, with a substantial portion (43%) of these risks manifesting within a 10-km radius around protected areas. In conclusion, our findings suggest that the high occurrence of HBCs in T & uuml;rkiye primarily stems from the limited availability of natural habitats and resources for brown bears, compounded by increased human encroachment in and around core bear habitats.