Researcher: Şekercioğlu, Çağan Hakkı
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Şekercioğlu, Çağan Hakkı
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Publication Metadata only Importance of Ethiopian shade coffee farms for forest bird conservation(Elsevier, 2015) Buechley, Evan R.; Atickem, Anagaw; Gebremichael, Gelaye; Ndungu, James Kuria; Mahamued, Bruktawit Abdu; Beyene, Tifases; Mekonnen, Tariku; Lens, Luc; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589Coffee is the most important tropical commodity and is grown in high-priority areas for biological conservation. There is abundant literature on the conservation value of coffee farms internationally, but there has been little research on this topic in Africa. Ethiopia is a diverse and little-studied country with high levels of avian endemism, pressing conservation challenges, and where Coffee arabica originated. We sampled bird communities in shade coffee farms and moist evergreen Afromontane forest in Ethiopia utilizing standard mist netting procedures at seven sites over three years to evaluate bird species richness, diversity and community structure. Although species diversity did not differ between shade coffee and forest, shade coffee farms had over double the species richness of forest sites and all but one of the nine Palearctic migratory species were captured only in shade coffee. There was a greater relative abundance of forest specialists and understory insectivores in forest, demonstrating that little-disturbed forest is critical for sustaining these at-risk groups of birds. Nonetheless, all species recorded in primary forest control sites were also recorded in shade coffee, indicating that Ethiopian shade coffee is perhaps the most "bird-friendly" coffee in the world. This is an important finding for efforts to conserve forest birds in Africa, and for shade coffee farmers that may benefit from avian pest regulation and biodiversity-friendly coffee certifications.Publication 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 Conservation of ecosystem services does not secure the conservation of birds in a Peruvian shade coffee landscape(Cambridge Univ Press, 2017) Aerts, Raf; Spranghers, Sarah; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589Agricultural intensification in shade coffee farms has strong impacts on the structure and diversity of the agroforest, with negative consequences for forest specialist birds, understorey insectivores and their associated ecosystem services. Utilising variable distance transect counts, we sampled the bird community in a multiple-certified yet changing shade coffee landscape in the Peruvian East Andean foothills, to evaluate bird functional diversity and to assess potential impacts of coffee production on avian ecosystem services. To account for incomplete detection, we also calculated expected species richness per functional group, and to evaluate the effect of future species losses, we derived reduced bird communities by subsampling our data using a Monte Carlo procedure. We compared the relative abundances of functional groups based on preferred diets in the observed, expected and reduced bird communities to global functional signatures of tropical bird assemblages of forest, agroforests and agriculture. The birds in the shade coffee landscape were predominantly birds of secondary and disturbed forest habitats, indicating, as expected, strong human impact on the forest structure. Yet, the diet signatures of the observed, expected and simulated bird communities were not significantly different from global diet signatures of forest and agroforest bird communities of mixed tropical landscapes. Our results suggest that avian ecological function can be conserved at bird community level despite intensive human ecosystem use and associated losses of forest specialist and other less resilient bird species. These results underscore that forest management strategies or certification audits focused solely at ecosystem services may be insufficient to support conservation of rare or threatened bird species and that shade coffee systems can in no way replace the role of protected natural forests.Publication Metadata only Temperature-associated decreases in demographic rates of afrotropical bird species over 30 years(Wiley, 2021) Neate-Clegg, Montague H. C.; Stanley, Thomas R.; Newmark, William D.; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589Tropical mountains harbor globally significant levels of biodiversity and endemism. Climate change threatens many tropical montane species, yet little research has assessed the effects of climate change on the demographic rates of tropical species, particularly in the Afrotropics. Here, we report on the demographic rates of 21 Afrotropical bird species over 30 years in montane forests in Tanzania. We used mark-recapture analyses to model rates of population growth, recruitment, and apparent survival as functions of annual mean temperature and annual precipitation. For over one-half of focal species, decreasing population growth rates were associated with increasing temperature. Due to the trend in temperature over time, we substituted a time covariate for the temperature covariate in top-ranked population growth rate models. Temperature was a better explanatory covariate than time for 6 of the 12 species, or 29% of all focal species. Population growth rates were also lower for species found further below their elevational midpoint and for smaller-bodied species. Changes in population growth rates were more closely tied to changes in recruitment than to changes in apparent survival. There were no consistent associations between demographic rates and precipitation. This study demonstrates temperature-associated demographic impacts for 6 (29%) of 21 focal species in an Afrotropical understory bird community and highlights the need to incorporate the impacts of climate change on demographic rates into conservation planning across the tropics.Publication Metadata only Conservation of migratory species(Cell Press, 2018) Horns, Joshua J.; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589N/APublication Metadata only Why birds matter: from economic ornithology to ecosystem services(Springer, 2015) Whelan, Christopher J.; Wenny, Daniel G.; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589Birds are conspicuous in many habitats, occur worldwide, are ecologically diverse, and are better known than other vertebrate groups. Birds devour pests, pollinate flowers, disperse seeds, scavenge carrion, cycle nutrients, and modify the environment in ways that benefit other species. Investigation of these ecosystem functions directly as ecosystem services has grown immensely over the last two decades and the ecological relevance of birds is well established. Birds are also observed, fed, and used as artistic and spiritual inspiration by millions of people around the globe. Yet the economic relevance of birds is not widely appreciated and the economic relevance to human society of birds' ecological roles is even less understood. Quantifying the services provided by birds is crucial to understand their importance for ecosystems and for the people that benefit from them. In this paper, we briefly review the rise and fall of economic ornithology and call for a new economic ornithology with heightened standards and a holistic focus within the ecosystem services approach. Birds' ecological roles, and therefore, ecosystem services, are critical to the health of many ecosystems and to human well-being. By understanding and valuing bird services and disservices through careful natural history research, we can better assess the environmental consequences of bird declines and extinctions and communicate these findings to the public and policy makers, thereby increasing public support for the conservation of birds and their habitats.Publication Metadata only NGOS for environmental sustainability: the case of KuzeyDoga foundation(Parlar Scientific Publications, 2016) Akkucuk, Ulas; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589The importance of volunteer-based environmental organizations is increasing throughout the world and in Turkey. Globally, there is a large number of NGOs operating in the field of environmental conservation. KuzeyDoga Society operating in Kars since 2007 is one of these institutions. The purpose of this paper is to examine the KuzeyDoga Society in terms of its conservation related activities. The activities of the foundation have been examined primarily through the organization's web sites, publications, social media presence, news stories about the organization and interviews with the founder. The analyses have shown that the activities of the organization range from leading the creation of Turkey's first wildlife corridor to lobbying for the declaration of Kuyucuk Lake as a European Destination of Excellence (EDEN). The society has succeeded in marketing the conservation message to a broad audience through the effective use of traditional and social media outlets. KuzeyDoga provides a good case study of the conservation marketing strategies of a small but effective nongovernmental organization that is rarely seen in Turkey.Publication Metadata only Similar bird communities in homegardens at different distances from Afromontane forests(Cambridge Univ Press, 2017) Engelen, Dries; Lemessa, Debissa; Hylander, Kristoffer; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589Human modified landscapes make up a growing proportion of the tropics, but are relatively little studied. The spatial distribution of remnant vegetation can structure and shape local biodiversity, affecting the provisioning of ecosystem services and regulation of pest problems. We compared species composition, abundance and functional diversity of birds between forest and homegardens close to (0-100 m) and further away from (1,500-2,000 m) moist evergreen Afromontane forests in south-western Ethiopia. We thoroughly inventoried birds with point counts and mist netting in two forest sites and three garden sites of each type. Gardens differed in general species composition from forests, with fewer forest specialist species (7% versus 29% of recorded species), but instead supported many other species that were rarely encountered in the forests. Overall gardens had higher numbers of species than forests. Homegardens close to the forest and further from the forest were similar to each other in terms of species richness and overall species composition. Both garden types had a similar composition in terms of the relative proportion of species with different habitat preferences as well as the composition of species from different feeding guilds. The lack of forest specialists in even the most structurally complex part of the agricultural landscape close to forest edges suggests that the last larger forest remnants are critical for conservation of forest specialists. Nonetheless, homegardens maintain rich bird diversity that also should be considered in a biodiversity conservation context. Further research is needed to establish to what extent the richness and composition of the agro-ecological bird fauna is regulated by the existence of forest patches in the region. Our results could not resolve this question since gardens two kilometers from the forest edge were similar in composition to gardens close to the forest edges.Publication Metadata only Insectivorous birds consume an estimated 400-500 million tons of prey annually(Springer, 2018) Nyffeler, Martin; Whelan, Christopher J.; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589In this paper, we present an estimate of the predation impact of the global population of insectivorous birds based on 103 (for the most part) published studies of prey consumption (kg ha(-1) season(-1)) of insectivorous birds in seven biome types. By extrapolation-taking into account the global land cover of the various biomes-an estimate of the annual prey consumption of the world's insectivorous birds was obtained. We estimate the prey biomass consumed by the world's insectivorous birds to be somewhere between 400 and 500 million metric tons year(-1), but most likely at the lower end of this range (corresponding to an energy consumption of ae 2.7 x 10(18) J year(-1) or ae 0.15% of the global terrestrial net primary production). Birds in forests account for > 70% of the global annual prey consumption of insectivorous birds (a 300 million tons year(-1)), whereas birds in other biomes (savannas and grasslands, croplands, deserts, and Arctic tundra) are less significant contributors (a 100 million tons year(-1)). Especially during the breeding season, when adult birds feed their nestlings protein-rich prey, large numbers of herbivorous insects (i.e., primarily in the orders Coleoptera, Diptera, Hemiptera, Hymenoptera, Lepidoptera, and Orthoptera) supplemented by spiders are captured. The estimates presented in this paper emphasize the ecological and economic importance of insectivorous birds in suppressing potentially harmful insect pests on a global scale-especially in forested areas.Publication Metadata only Assessing genetic diversity patterns at neutral and adaptive loci to inform population reinforcement of an endangered migratory vulture(Springer Nature, 2023) Bounas, Anastasios; Saravia-Mullin, Victoria; Méndez, Maria; Arkumarev, Volen; Aghajanyan, Lusine; Ararat, Korsh; Buechley, Evan; Dobrev, Vladimir; Dobrev, Dobromir; Efrat, Ron; Klisurov, Ivaylo; Kret, Elzbieta; Skartsi, Theodora; Oppel, Steffen; Petrov, Rusko; Vaidl, Anton; Donázar, José A.; Nikolov, Stoyan C.; Sotiropoulos, Konstantinos; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589One of the primary goals of conservation translocation programs should be the maintenance of both population demographic stability and genetic diversity. Here, we provide genetic management recommendations to inform a population reinforcement of the declining Egyptian Vulture population in the Balkans. Specifically, we examined whether the number of released individuals is sufficient to prevent genetic diversity loss due to random genetic drift and what the origin of the individuals should be that comprise the captive breeding pool. To this aim, we estimated and assessed genetic diversity levels and genetic structure of Egyptian Vulture populations across much of the species’ range using both neutral and non-neutral candidate loci involved in migration. We then evaluated the effects of the currently proposed population management scheme and candidate source populations on retaining allelic diversity. Our results show low differentiation values among populations and absence of genetic structure which point to past high gene flow. Furthermore, there was no predicted significant impact of different source populations on the genetic diversity of the recipient Balkan population. We also found that the declining Egyptian Vulture population in the Balkans still retains high levels of genetic diversity and therefore genetic diversity restoration is not currently needed. However, without any management, diversity is likely to decrease fast because of increased genetic drift as the population size continues to decline. Population reinforcement with nine birds per year for 20 years would provide sufficient demographic support for the population to retain > 85% of rare allelic diversity. Birds originating from the Balkans would ensure ecological and behavioral similarity and thus would be the best option for reinforcement. Nevertheless, our results demonstrate that to prevent further population contraction and loss of adaptive alleles, releasing individuals of different origin would also be appropriate.