The value of community science data to analyze long-term avian trends in understudied regions:The state of birds in Türkiye

Recent studies have revealed concerning declines in bird populations in Europe and other parts of the world.In understudied but biodiverse regions,especially those that are located along key migratory flyways,there is an unmet need to evaluate the status of resident and migratory birdlife for avian conservation ecology.This is especially urgent at a time when recent regional studies have highlighted the scale of the decline of the European and Palearctic avifauna.Rapidly growing community science datasets may help bridge the gaps in our understanding of long-term regional avifaunal trends.In this study,we used eBird data submitted by observers in Türkiye to undertake the first long-term assessment of the state of the country’s birds from 2001 to 2022.We evaluated population trends based on presence-absence data of species to determine if any birds have significantly increased or decreased in the country so far this century.We provide a list of trends for 418 bird species that had large enough sample sizes of eBird observations from Türkiye,and highlight which species have significantly declined or increased.We found that 63 species have significantly declined in detection while 120 have significantly increased during the study period.Our findings provide a baseline for the future monitoring of Türkiye’s birds and help contextualize population changes of birds in Türkiye against those occurring at the continental(Palearctic)scale.Additionally,we include movement classifications for all of the bird species in this study.We also provide a framework to effectively use eBird data to assess long-term avifaunal changes at the country-level in other understudied regions.Finally,we highlight ways in which eBirders in Türkiye and elsewhere can strengthen the quality and value of community ornithology data for population assessments and avian conservation ecology.

Endangered lowland oak forest steppe remnants keep unique bird species richness in Central Hungary

The biodiversity of natural or semi-natural native,old oak woodlands have high conservation importance,especially in landscapes of monocultural forest plantations and arable fields.With a wider variety of microhabitats and foraging sources,such old oak forests can provide essential habitat for native forest bird communities.We conducted a study using bird point counts to compare the forest bird communities of old pedunculate oak(Quercus robur)remnants with native and non-native plantations in central Hungary in a landscape of mostly arable fields,settlements,and monocultural plantations.Avian surveys were carried out in old oak forest remnants,middle-aged oak,white poplar(Populus alba),hybrid poplar(Populus×euramericana),black locust(Robinia pseudoacacia),and pine(Pinus spp.)plantations.Fieldwork has been carried out in nine study sites,where all six habitat types were represented(with a few exceptions),to determine total abundance,species richness,Shannon–Wiener diversity,species evenness,dominant and indicator species,and guild abundances.We found that old oak forest remnants were the most diverse habitats among the studied forest types,while hybrid poplar and pine plantations exhibited the lowest avian biodiversity.The avian guilds most sensitive to the loss of old oak forest remnants were ground foragers,bark foragers,cavity-nesters,residents,and Mediterranean migratory birds.Native habitats were more diverse than non-native plantations.Our results suggest that it is important to conserve all remaining high biodiversity old oak stands and to avoid clear-cutting of monocultural plantations in favour of practices such as mixed-species plantations,longer rotation lengths,or retention forestry.

Multidimensional diversity of bird communities across spatial variation of land cover in Zoige on the eastern Qinghai-Tibetan Plateau

Background:Spatial variation of land cover can result in the changes of community similarities and biotic homog-enization,whereby the increasing similarity would reduce the adaptive capacity of biotic assemblages to further disturbance,and degenerate ecosystem services they offer.However,it remains scarce to integrate multidimensional diversity for unveiling how variations in land cover may influence the patterns and processes of biotic homogeniza-tion in the Anthropocene.In this study,we examined how spatial variation of land cover could alter taxonomic,phy-logenetic and functional homogenization of bird communities simultaneously in a compound ecosystem of Zoige Marsh on the eastern Qinghai-Tibetan Plateau.Acting as the largest alpine marsh and peatland in the world,Zoige Marsh has undergone great changes in the land cover pattern due to climate change and anthropogenic activities.Methods:We conducted transect surveys for bird communities over six years(2014‒2019)during breeding sea-sons in four main land cover types(meadow,woodland,village and marsh),representing the spatial variation of land covers in the study area.We compared multidimensional diversity(taxonomic,phylogenetic and functional diver-sity)among land covers to assess the effects of spatial variation in land cover type on bird communities,particularly whether this variation has homogenized biotic communities.Results:Bird communities during breeding seasons were different and complementary in the four land covers.Taxonomic,phylogenetic and functional similarities were significantly lower in meadow than in the other three types,i.e.woodland,village and marsh.However,when we controlled for the effects of taxonomic similarities,the pattern of phylogenetic similarities almost reversed,with the highest standardized effect size(SES)phylogenetic similarity in meadow;and we found no significant difference in SES functional similarity among land covers.Conclusions:Our results suggest that spatial variation of land cover can play a crucial role in regulating multiple dimensions of bird diversity in Zoige Marsh.The findings indicate that taxonomic,phylogenetic and functional homogenization of bird communities may differently response to the variation of land covers.It thus highlights not only the relative roles of different land covers in maintaining biodiversity and community structures of birds,but also the urgency of retarding ecosystem degradations on the eastern Qinghai-Tibetan Plateau.

The Genesis and Evolution of the Caspian Sea Lagoons as Avifauna Refuges at the Transboundary Scale

The article summarizes 34 years (1980-2014) of the original observations of the genesis and evolution stages of the Caspian lagoons. A model of the formation and evolution of the coastal lagoons has been worked out. It can be applied to the modelling of the global geoecological scenario along all the world’s coasts characterized by a steady transgression of their marine areas. The lagoons had been formed in a “bottleneck”, a narrow migration corridor, traversed by the largest migration route of trans-Palearctic species in Russia. This route is part of the West Siberian-East African migration range. Year round bird censuses (n = 746) were taken by the author in 1995-2014 along two key routes in the regions of Turalinskaya and Sulakskaya lagoons of Daghestan (the western coast of the Middle Caspian Sea). The meridional orientation of lagoons, location of the migration trajectory and a wide range of habitats in the study area contribute to the preservation of 294 Eurasian bird species. After formation of the lagoons, the breeding avifauna of the Caspian Sea Region of Central Daghestan has added 32 taxa. Among the species recorded at the lagoons, 50 are included in the IUCN Red List, Red Data Books of Russia and Daghestan. The reconstruction analysis of the migration trajectory compiled according to the data of the Russian Bird Ringing Centre allowed us to determine the population distribution geography for the birds regularly migrating along the western coast of the Caspian Sea and refine borders of theWest Siberian-East African migration range. Thus, according to the information received, the current migratory range should be greatly extended to cover the area from the British Isles in the West Palearctic to Lake Baikal in the east, including the extreme west and south of Africa.