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Öğe Abundance of Apodemus spp. varies by stand age in coppice-originated oak forest, Thrace, Turkey(Univ Austral Chile, Fac Ciencias Forestales, 2016) Keten, Akif; Beşkardeş, Vedat; Makineci, Ender; Kumbaşlı, Meriç; Anderson, James T.Recently, oak (Quercus spp.) management strategies in Turkey have transitioned from predominantly coppice-regeneration to seed regeneration. However, impacts of this change on the small mammal community is unknown. To address this issue we evaluated abundance of Apodemus spp. (Rodentia, Muridae) in relation to stand age and forest characteristics in the northern Thrace, Turkey. We sampled 43 plots using box-style live traps. A total of 75 individuals (0.125 +/- 0.013 mice/trap nights) was captured. Apodemus flavicollis (n = 69) was the most abundant, although A. agrarius (1) and A. sylvaticus (4) also occurred. Apodemus spp. abundance was superior in older than in younger stands (P = 0.038). The number of specimens was positively related to diameter at breast height (DBH) (y = 0.18 + 0.015x, R-2 = 0.21) and forest floor mass (y = 0.005 + 0.00005x, R-2 = 0.22). Increasing the amount of forest floor mass and mast production will benefit the population of Apodemus spp. Abandonment of the coppice management on oak forests in Thrace may positively affect the local abundance of Apodemus spp., particularly A. flavicollis.Öğe Arthropod diversity in pure oak forests of coppice origin in northern Thrace (Turkey)(Sisef-Soc Italiana Selvicoltura Ecol Forestale, 2015) Keten, Akif; Beşkardeş, Vedat; Kumbaşlı, Meriç; Makineci, Ender; Zengin, Hayati; Özdemir, Emrah; Anderson, James T.Oak (Quercus spp.) forests are among the most important forest types in Turkey. In the past, oak forests were managed through coppice clear-cutting, but in recent decades they have mostly been converted to high forest. This study was aimed at explaining how arthropod diversity is affected during conversion from coppice to high oak forest and during the early stages of coppice succession. We tested the hypothesis that arthropod richness, abundance and diversity in coppice oak sites varied according to stand age and a number of other forest characteristics. Arthropod communities were sampled in 50 plots using four different methods: pitfall traps, sweep nets, sticky cards and cloth shaking. A total of 13 084 individuals were collected and classified into 193 Recognizable Taxonomic Units (RTUs), with the most RTUs and the greatest number of specimens captured by sweep netting. We identified 17 taxa within RTU's with more than 1% of the captured arthropods, which constituted 75% of the total specimens. The number of RTUs varied significantly according to trap type. Arthropod richness and Shannon-Wiener biodiversity index (H') increased with elevation and precipitation. In young (1-40 yrs-old) and middle-aged (4180 yrs) stands, arthropod biodiversity was not significantly affected by stand type, but slightly increased with diameter at breast height and tree height. Forest characteristics, such as the litter layer, understory and crown diameter, weakly influenced arthropod richness and abundance. Cluster analysis revealed that stand types and trap types differed taxonomically. Principal component analysis showed that stand types were clearly separated by the stand parameters measured. Insect families (Formicidae, Thripidae, Lygaeidae, Dolichopodidae, Luaxanidae, Cicadellidae and Ichneumonidae) could potentially be used as indicators of coppice oak conditions. As the coppice oak changes to mature forest, further studies are needed to better assess the relation between arthropods, forest types and structural characteristics of stands.Öğe Bird diversity along a riparian corridor in a moderate urban landscape(Elsevier, 2020) Keten, Akif; Eroglu, Engin; Kaya, Sertac; Anderson, James T.Civilization built around rivers directly affects riparian corridor structure and ecology. Degradation, pollution, and deterioration along riparian corridors in urban landscapes change species composition and biodiversity. Birds are one of the most vulnerable taxa to ecological changes. The main objective of our study was to spatially compare bird species richness, abundance, and community structure along the Asar River, an urban riparian corridor in Duzce, Turkey. We identified 63 bird species, comprising 6722 individuals, and classified them into one of three groups: generalist species (11 species), woodland species (40 species), and waterbird species (12 species). Bird species richness was positively related to vegetative cover and negatively to urbanization. Richness was low in the winter and was higher during spring and summer. Riparian Quality Index (RQI) scores (mean = 54.8 +/- 33.7; max. = 97 and min. = 5) were relatively low for all sampling plots and was reduced by human activities (e.g., roads, farmland, settlement). The number of woodland bird species changed positively (r = 0.71) with RQI. The generalist bird species, adapted to urbanization, were more common around settlements and open areas. Human population and settlement around Asar River increased one-third and farmland and natural habitat decreased onefifth during the last decade. The area has high potential for growth and increased urbanization, thus increasing the pressure on the natural areas. Activities that diminish the amount of tree cover in the riparian corridor should be avoided. Habitat restoration and rehabilitation will increase RQI values, which can be used as indicators for bird richness in urban landscapes and benefit avian diversity along the riparian corridor. The existing riparian corridor and any enhancements to the corridor will help conserve Duzce's biodiversity in the future.Öğe HABITAT USE BY TIT SPECIES IN THE YUVACIK WATERSHED, TURKEY(Parlar Scientific Publications (P S P), 2018) Beşkardeş, Vedat; Keten, Akif; Arslangündoğdu, Zeynel; Anderson, James T.Tits are small insectivorous passerines inhabiting much of Turkey; spatially distributed due to habitat selection. The objective of the current study was to document habitat preference of the tit community in the Yuvacik Watershed in northwestern Anatolian. We tested the hypothesis that tits abundance changed based on habitat types. We sampled a total of 12 plots from 4 habitat types (deciduous forest, coniferous forest, scrub-shrub, and farmland) monthly during 2007. We recorded four (4) tit species: Blue tit Cyanistes caeruleus, Coal tit Periparus ater, Great tit Parus major, and Marsh tit Poecile palustris; 354 individual birds were counted during 12 surveys. Tits were influenced by habitat types in Yuvacik watershed. Coal tit are adapted to coniferous forests. Great tit and Blue tit were distributed widely in coniferous forests, scrub-shrub areas, and farmlands. Marsh tit was associated primarily with deciduous woodland. Elevation, cover percentage, and vegetation height influenced positively the abundance of total and individual species. Three parameters (elevation (m), canopy cover (%), and maximum habitat height (m)) showed differences among habitat types for tit species. Coniferous forests and deciduous forests exhibited similar characteristic, as did scrub-shrub areas and farmlands. Tit species are resident and reproduce in the Yuvacik watershed. Hedgerows in farmland, and mature habitats should be protected and sustained to enhance breeding success of tits.Öğe Temporal patterns of wetland-associated bird assemblages in altered wetlands in Turkey(Polish Acad Sciences Inst Ecology, 2019) Keten, Akif; Sarcan, Erdinç; Anderson, James T.A loss of wetlands, one of the highly sensitive ecosystems, necessitates the monitoring and assessment of wildlife population trends for the continuity and sustainable management of species. The goal of our study was to evaluate temporal changes in wetland-associated bird composition by conducting monthly counts during December 2006 - November 2007 and March 2015 - February 2016 in Efteni Lake, Duzce, Turkey. This lake has been exposed to structural change including shoreline length, area and depth for the last 50 years. Wetland-associated bird richness decreased, and abundance increased during the decade, but this change was not significant except for two species with an increased population, ferruginous duck Aythya nyroca and great crested grebe Podiceps cristatus. Cluster analyses resulted in two groups: the breeding season from April to September, and the non-breeding season from October to March. The most numerous species were observed mostly during the non-breeding season. Some guilds, including diving carnivores, omnivores, shoreline omnivores and herbivores species were more prevalent during the non-breeding season. The insectivores had higher population densities during the breeding season. Thus, wetland-associated bird abundance during the non-breeding season was higher than during the breeding season, although species richness was the opposite. The planned restoration of habitats of Efteni Lake should have a positive impact on birds by creating more space available to them. Our result should help to better understand the impact of habitat changes on waterbird assemblages. Long-term monitoring of Efteni Lake will be useful for the wetland-associated avian community, and for other animal and plant communities.
