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- Heim, Wieland, et al.
(författare)
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Using geolocator tracking data and ringing archives to validate citizen-science based seasonal predictions of bird distribution in a data-poor region
- 2020
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Ingår i: Global Ecology and Conservation. - : Elsevier BV. - 2351-9894. ; 24
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Tidskriftsartikel (refereegranskat)abstract
- Unstructured citizen-science data are increasingly used for analysing the abundance and distribution of species. Here we test the usefulness of such data to predict the seasonal distribution of migratory songbirds, and to analyse patterns of migratory connectivity. We used bird occurrence data from eBird, one of the largest global citizen science databases, to predict the year-round distribution of eight songbird taxa (Agropsar philippensis, Calliope calliope, Cecropis daurica, Emberiza aureola, Hirundo rustica, Locustella certhiola, Oriolus chinensis, Saxicola torquatus stejnegeri) that migrate through East Asia, a region especially poor in data but globally important for the conservation of migratory land birds. Maximum entropy models were built to predict spring stopover, autumn stopover and wintering areas. Ring recovery and geolocator tracking data were then used to evaluate, how well the predicted occurrence at a given period of the annual cycle matched sites where the species were known to be present from ringing and tracking data. Predicted winter ranges were generally smaller than those on published extent-of-occurrence maps (the hitherto only available source of distribution information). There was little overlap in stopover regions. The overlap between areas predicted as suitable from the eBird data and areas that had records from geolocator tracking was high in winter, and lower for spring and autumn migration. Less than 50% of the ringing recoveries came from locations within the seasonal predicted areas, with the highest overlap in autumn. The seasonal range size of a species affected the matching of tracking/ringing data with the predictions. Strong migratory connectivity was evident in Siberian Rubythroats and Barn Swallows. We identified two migration corridors, one over the eastern mainland of China, and one along a chain of islands in the Pacific. We show that the combination of disparate data sources has great potential to gain a better understanding of the non-breeding distribution and migratory connectivity of Eastern Palearctic songbirds. Citizen-science observation data are useful even in remote areas to predict the seasonal distribution of migratory species, especially in periods when birds are sedentary and when supplemented with tracking data.
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| 2. |
- Ktitorov, Pavel, et al.
(författare)
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Shrub-dwelling species are joining the Arctic passerine bird community in the Chaun Delta (Western Chukotka, Russia)
- 2021
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Ingår i: Polar Biology. - : Springer Science and Business Media LLC. - 0722-4060 .- 1432-2056. ; 44:9, s. 1847-1857
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Tidskriftsartikel (refereegranskat)abstract
- Avian communities play a pivotal role in Arctic ecosystems and birds have become the key model taxa for climate change research. Due to funding priorities, Arctic passerines have been studied less intensively than waterfowl and shorebirds. In our study, we aim to partly fill this gap and look at the change in passerine community species composition in the Chaun River Delta in Northeast Siberia (68.81° N, 170.62° E) between 1970–1980 and 2002–2019. We restricted our comparison to 16 tundra-dwelling species associated with grass and shrub tundra habitats. During the first period, 12 passerine species were reported and by the end of the last period, 14 species. Our observations show that four species of shrub-dwelling passerines, the Dusky Warbler (Phylloscopus fuscatus), two species of Turdus thrushes, and the Siberian Rubythroat (Calliope calliope), have joined the local community. Additionally, one Turdus thrush species increased in numbers. The only passerine species that used to be common in the 70’s and rare in the 2000s is the Lapland Bunting (Calcarius lapponicus). Yellow-breasted Bunting (Emberiza aureola, vagrant in 70’s) and Siberian Chiffchaff (Phylloscopus tristis, rare breeder in 70’s) have not been recorded during the most recent period. At the same time, there was no observed change in abundance for eight species of songbirds. The results of supervised satellite image classification did not detect any local-scale increase of shrub cover in our study site. However, a broad-scale assessment of vegetation change using NDVI suggests substantial greening or ‘shrubification’ across the region. We speculate that it promotes region-wide increases and range expansion of some shrub-dwelling species, recorded in our study.
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