European farmland birds show massive large‐scale population declines due to agricultural intensification. Long‐distance migrants are particularly affected as their populations appear to undergo larger declines than those of residents and short‐distance migrants, raising the question about the impact of non‐breeding environmental conditions and their potential impact on annual survival. The whinchat Saxicola rubetra, an Afro‐Palaearctic migrant inhabiting open habitats, has strongly declined over the last decades. Most of the conservation effort for this species has focused on improving the breeding success in Europe, but it remains unclear whether habitat changes in non‐breeding areas may also have contributed to the population declines through a decrease in adult survival. We studied survival of whinchats from eight breeding populations across Europe by analysing capture–recapture data. We found that apparent survival was consistently higher in males than in females and higher in successful than in failed breeders independently of the sex. True adult survival may, however, hardly differ between sexes being about 0.5 and 0.6 and a simple population model suggests true juvenile survival to be between 0.2 and 0.35. Adult survival was unrelated to population trends suggesting that the main demographic problem of the whinchats is likely insufficient reproduction, a feature that is shared with other declining grassland specialists. Finally, in line with results on other migratory farmland species, our study suggests that conservation activities for whinchats should in first place focus on Europe.
The habitat suitability for the Common Pochard, a duck species in decline, was studied in the middle reaches of the Orel’ River, Central Ukraine, in 2015–2017. The ducks were counted on their breeding grounds with the use of the ground survey technique. The positions of individual birds were estimated by GPS and plotted on the Google Earth map. The Ecological Niche Factor Analysis (ENFA) was applied to assess the habitat suitability. Sentinel-2 image was used to extract 13 ecogeographical variables and to get two measures of the ecological niche (marginality and specialization). The ENFA procedure was applied twice at landscape and sub-landscape levels to describe the habitat selection across sequential spatial scales. Both the axes of marginality and specialization of the ecological niche of the species proved to be significantly different from the random alternatives. At landscape level, the distribution may be predicted with the use of Aerosol/Coastal, Vegetation and Hydrothermal Composite indices (marginality) and Modified Normalized Difference Water (MNDW) Index along with several vegetation indices (specialization). At sub-landscape level, MNDW played a crucial role. The importance of MNDW is mediated by the preference for the wetlands with the stretches of open water which are used by the ducks to initiate flight safely and to optimize diving possibilities. The ENFA is a reliable tool for the assessment of the habitat suitability and for setting the conservation priorities for the Common Pochard.
The studies of species composition and abundance of diurnal birds of prey may be quite indicative of the state of natural ecosystems and of the level of impact of human-induced factors on their functions. Such studies are particularly important within the protected areas taking into account unfavourable conservation status of many species of the group. The status, abundance, aspects of habitat distribution and breeding habitat preferences of diurnal birds of prey were studied within national nature park ‘Dvorichanskyi’ and adjacent territories (750 sq. km, Dvorichanskyi district, Kharkiv Region, Ukraine) in 2010–2018. 22 species were registered. The breeding of six species was confirmed e.g. Black Kite (Milvus migrans), Marsh Harrier (Circus aeruginosus), Goshawk (Accipiter gentilis), Sparrowhawk (Accipiter nisus), Common Buzzard (Buteo buteo), Booted Eagle (Hieraaetus pennatus). The breeding of four more species is considered probable namely Honey Buzzard (Pernis apivorus), Montagu’s Harrier (Circus pygargus), White-tailed Eagle (Haliaeetus albicilla) and Hobby (Falco subbuteo). There are indications of possible breeding of Short-toed Eagle (Circaetus gallicus) and Kestrel (Falco tinnunculus). The rest of the species are migrating and/or wintering. The most numerous breeding species is Common Buzzard. The abundance of Booted Eagle is comparatively high that discerns the study area from other parts of Kharkiv Region. 40 nests of birds of prey were carefully inspected. The majority were found in ravine steppe forests (83%). Oak, alder and willow flood-plain forests are very important breeding habitats for Black Kite and Booted Eagle while ravine steppe forests are those for Goshawk, Sparrowhawk, Common Buzzard and Booted Eagle. Pedunculate oak (Quercus robur) is the most favourable tree species for building the nests (47.5% of all inspected nests) followed by European ash (Fraxinus excelsior) (15%) and European pear (Pyrus communis) (10%).
The Eurasian Otter (Lutra lutra) in Water Bodies of the Forest-Steppe and Steppe Zones of Northeastern Ukraine.-Skorobogatov, Eu., Atemasov, A., Banik, M.-The status of the Eurasian otter (Lutra lutra L., 1758) in water bodies of the Kharkiv oblast (Northeastern Ukraine) was assessed during expedition surveys in 2007-2008. The aspects of the otter's distribution in small (SR) and medium (MR) rivers in the forest-steppe and steppe natural zones were analyzed. The otter's density in SR was 0.4 ind./10 km and 0.6 ind./10 km of riverbed in the forest-steppe and steppe zones, accordingly, and 0.8 ind./10 km in MR in both zones. The length of individual and family territories of the otter was 3.2-28 km (n = 17, M = 14.5 ± 2.3) in SR, and 7-8 km (n = 2, M = 7.5 ± 0.5) in MR. Flood-plain habitats in SR valleys in the steppe zone are considerably less forested than in the forest-steppe zone. However, the extent of overgrowth of the riverbed by emergent and submerged vegetation is markedly higher in SR of the steppe zone (80-90 % versus 30-50 % in SR of the forest-steppe zone). This probably results in lesser disturbance of the otter's habitats by humans, and indirectly may be reflected in higher densities of otter populations in the steppe zone. Key wo rds: Eurasian otter (Lutra lutra), small rivers, distribution, abundance, family territories, individual territories. Видра річкова (Lutra lutra) у водоймах лісостепової та степової зон Північно-східної України.-Скоробогатов, Є., Атемасов, А., Банік, М.-Статус видри річкової (Lutra lutra L., 1758) в водоймах Харківської обл. (північно-східна частина України) оцінювали в ході експедиційних досліджень у 2007-2008 рр. Проаналізовані особливості розповсюдження виду в малих (МР) та середніх річках (СР) лісостепової та степової фізико-географічних зон. Щільність заселення видрою МР оцінювалась як 0,4 особ./10 км та 0,6 особ./10 км русла річки для лісостепової та степової зони, відповідно, для СР-0,8 особ./10 км русла річки для обох зон. Протяжність сімейних та індивідуальних ділянок видри для МР становила 3,2-28 км (n = 17, M = 14,5 ± 2,3), для СР-7-8 км (n = 2, M = 7,5 ± 0,5). Заплавні біотопи малих річок степової зоні відрізняються значно меншим коефіцієнтом заліснення, але заростання гідрофітами русла для них складає 80-90 % проти 30-50 % для МР лісостепової зони. Це, ймовірно, впливає на ступінь використання МР степової зони людиною і може опосередковано відбиватися у щільності заселення цих водойм видрою. К л ю ч ов і с лов а: видра річкова (Lutra lutra), малі річки, розповсюдження, чисельність, сімейні ділянки, індивідуальні ділянки.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.