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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 Are signals of aggressive intent less honest in urban habitats?(Oxford Univ Press Inc, 2020) Beck, Michelle L.; Sewall, Kendra B.; Department of Psychology; Akçay, Çağlar; Faculty Member; Department of Psychology; College of Social Sciences and Humanities; 272053How anthropogenic change affects animal social behavior, including communication is an important question. Urban noise often drives shifts in acoustic properties of signals but the consequences of noise for the honesty of signals-that is, how well they predict signaler behavior-is unclear. Here we examine whether honesty of aggressive signaling is compromised in male urban song sparrows (Melospiza melodia). Song sparrows have two honest close-range signals: the low amplitude soft songs (an acoustic signal) and wing waves (a visual signal), but whether the honesty of these signals is affected by urbanization has not been examined. If soft songs are less effective in urban noise, we predict that they should predict attacks less reliably in urban habitats compared to rural habitats. We confirmed earlier findings that urban birds were more aggressive than rural birds and found that acoustic noise was higher in urban habitats. Urban birds still sang more soft songs than rural birds. High rates of soft songs and low rates of loud songs predicted attacks in both habitats. Thus, while urbanization has a significant effect on aggressive behaviors, it might have a limited effect on the overall honesty of aggressive signals in song sparrows. We also found evidence for a multimodal shift: urban birds tended to give proportionally more wing waves than soft songs than rural birds, although whether that shift is due to noise-dependent plasticity is unclear. These findings encourage further experimental study of the specific variables that are responsible for behavioral change due to urbanization.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 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 Ecological and biogeographical predictors of taxonomic discord across the world's birds(Wiley, 2021) Neate-Clegg, Montague H. C.; Blount, J. David; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589Aim Species delimitation is fundamental to biology, but disagreement in species concepts and the application of those concepts can lead to substantial variation in species lists, with important implications for conservation. For birds, there are four widely used global checklists that vary in length and application. Here, we investigate the biogeographical and ecological predictors of taxonomic disagreement between the four world bird species lists. Location Global. Time period Present. Major taxa studied Birds. Methods We determined taxonomic agreement based on whether each bird species name represented only one species ('agreement'), that is, no authorities have split the species, or represented multiple species ('disagreement') including disputed splits recognised by some authorities. We examined taxonomic agreement for all birds and for each family and biogeographical region. We then modelled taxonomic agreement as a function of six biogeographical and ecological variables: latitude, island endemism, log(mass), forest dependency, primary diet, and migratory status. Results Overall taxonomic agreement was 89.5%, and the remaining 10th of taxonomic names represented disputed splits upon which the four authorities disagreed. We found that taxonomic agreement was lowest for species in Southeast Asia/Australasia and the Southern Ocean, understudied regions where islands have driven high levels of cryptic diversification. In contrast, agreement was highest in the temperate Northern Hemisphere where diversity is lower and research is more extensive. Agreement was also higher for large, migratory species living in open habitats. Main conclusions Taxonomic agreement was higher for species that are easier to study such as large, temperate species from open habitats. In addition, agreement was lower for lineages that are more likely to undergo cryptic divergence such as island endemics with intermediate forest dependency and mobility. Species with these traits should be the focus of taxonomic research in order to achieve reconciliation of the world's bird lists and to better conserve extant biodiversity.Publication Metadata only Ecosystem services valuation using InVEST modeling: case from southern Iranian mangrove forests(Elsevier, 2023) Dashtbozorgi, Fatemeh; Hedayatiaghmashhadi, Amir; Dashtbozorgi, Ameneh; Ruiz-Agudelo, Cesar Augusto; Furst, Christine; Cirella, Giuseppe T.; Department of Physics; Naderi, Mortaza; Researcher; Department of Physics; College of Sciences; N/AAs one of the most fertile ecosystems on earth, mangrove forests provide many goods and services for humanity. Mangroves are located in the south of Iran on the coasts of Sistan and Baluchistan, Hormozgan and Bushehr provinces, which include two species of Harra (Avicennia marina) and Chandal (Rhizophora mucronata) The purpose of this study was to describe the condition of mangrove forests using the integrated valuation of ecosystem services and tradeoffs (InVEST) between 2010 and 2021 from the southern coasts of Iran. The INVEST model uses land use and land cover maps to estimate habitat quality. With the opinions of local experts, sources of threats, maximum impact distance, state of degradation, and sensitivity to threats were also estimated for each type of land use cover. Urban and rural areas' development, roads network, piers, oil and non-oil industries, agriculture, and aquaculture activities, were identified as sources that threaten mangroves' long-term viability. The output maps of the INVEST habitat quality model included degradability and habitat quality maps, which were classified into four categories: poor, low, medium, and high, to better understand quality changes. The results demonstrated that mangrove habitat quality has decreased considerably despite the increase in their area. The area of the target habitats has been increased by 586.45 ha while two first quality categories, including poor and low classes, increased. Based on a habitat quality assessment in 2010, two classes of poor, low habitat quality, were estimated to be around 0.72, and 8.42 ha, which changed to 3.04 ha, and 9.72 ha respectively in 2021. The output maps obtained in this study can help local managers and decision-makers to have an image of what happened to the quality of the target ecosystems and may help them to adopt more effective management strategies for the conservation of these ecosystems.Publication Metadata only Effect of human-induced activities on waterbirds diversity and abundance in three wetlands of international importance in Iran(Maik Nauka/Interperiodica/Springer, 2019) Golzar, E.; Esfandabad, B. Shams; Morshedi, J.; Jozi, S. A.; Department of Physics; Naderi, Mortaza; Researcher; Department of Physics; College of Sciences; N/AOver six years from 2011 to 2015, direct field observations and waterbirds' surveys were performed in three Ramsar sites (Choghakhor, Shadegan and Parishan). Our results indicated that all three wetlands affected by developing intensive farming systems and lowered species richness. The most important difference existing among the wetlands points to the habitat of the specialist waterbirds, while we found no significant differences in the habitat of the generalist birds. Meanwhile, some completely dependent birds like White-headed Duck (Oxyura leucocephala) have completely disappeared. Our results indicated that 87 percent of the variation in the species richness and abundance can be justified by a combination of water depth, water area, sludge depth, conductivity, total phosphorus, newly developed farming areas and vegetation cover.Publication Metadata only Elevational changes in the avian community of a mesoamerican cloud forest park(Wiley, 2018) Neate-Clegg, Montague H. C.; Jones, Samuel E. I.; Burdekin, Oliver; Jocque, Merlijn; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589Harboring many range-restricted and specialized species, high elevation tropical cloud forests are diverse habitats represented in many protected areas. Despite this, many such areas receive little practical protection from deforestation and land conversion. Moreover, montane species may be more sensitive to climate change owing to various factors affecting community assembly across elevational gradients. Few studies have used annual monitoring to assess how biological communities in cloud forests may be shifting in response to habitat or climate change or assessed the efficacy of protected areas in buffering these effects. We analyzed avifaunal community trends in a 10-yr dataset of constant-effort bird point-count data in a cloud forest national park in Honduras, Central America. We found that species richness and diversity increased at higher elevations, but decreased at lower elevations. Abundances of most dietary and forest-dependency groups exhibited similar trends, and many key cloud forest species shifted upslope and/or increased in abundance. Taken together, our results suggest that the avian community is moving upslope and species composition is changing. Results for species richness and diversity were similar when only nondegraded transects were considered, suggesting the role of climate change as an important driver. At lower elevations, however, many species may be negatively affected by increased habitat degradation, favoring species with low forest dependency. Continued habitat conversion and climate change could push the cloud forest bird community further upslope, potentially resulting in increased competition, mortality, and even extirpation of some species. Increased protection is unlikely to mitigate the effects of climate change.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.