Konzervációbiológia a gyakorlatban: természetvédelmi kezelés és tájrehabilitáció az Egyek-Pusztakócsi LIFE-Nature programban

A konzervációbiológia gyakorlati alkalmazása világszerte gyakran akadozik az információk elérhetőségének és/vagy felhasználásának hiánya miatt. Írásunk a konzervációbiológia ismereteinek gyakorlati alkalmazására szolgál példával az Egyek-Pusztakócsi mocsárrendszer (Hortobágyi Nemzeti Park) rehabilitációjának második, LIFE-Nature pályázat keretében zajló üteme kapcsán. A tájszintű rehabilitációban összesen mintegy 920 ha szántón gyepek rekonstrukciójára, erdőtelepítésre és extenzív „apróvadföldek” művelésére, míg 720 ha mocsár- és gyepterületen a mozaikos élőhelyszerkezet kialakítását célzó természetvédelmi kezelésre (legeltetés, égetés) kerül sor. A program révén nő az élőhelyi sokféleség, kedvezőbb tájszerkezet és az ökológiai adottságokhoz jobban illeszkedő tájhasználat jön létre, melynek tapasztalatai hozzájárulhatnak a tudományos alapú természetvédelem további terjedéséhez

A Meggyes-mocsár vegetációja a természetvédelmi rehabilitáció kezdeti fázisában

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Harem size should be measured by more than the sum of its parts: Phenology‐based measurements reveal joint effects of intrinsic and extrinsic factors on a polygamous herbivore under non‐stationary climatic conditions

Abstract Social behaviour is thought to be a major component of survival, reproduction, and resilience of populations. Thus, it is a key component in management and conservation of wild populations. In polygynous breeding species, group size influences the reproductive success of males and females, and hence it is essential to understand the environmental and demographic factors that shape the phenology of group size within populations. Here, we investigate harem size and its determinants using a 15‐year dataset of annual harem size phenology‐based metrics from a reintroduced population of wild Przewalski horses in Hortobágy National Park, Hungary. From the initial reintroduction of 21 animals in 1997, the population grew to 174 animals in 2012. During that same period, the number of harems increased from three to 23. Despite the 8‐fold increase in population size, harem sizes remained stable, and variability among harems within years decreased. The annual phenological cycle of harem size was not consistent over the 15‐year period, and the associated annual phenology‐based metrics varied differently over the years. The best predictors of our phenology‐based harem size metrics were adult sex ratio, annual adult mortality and annual mean number of harems, with some evidence that mean age of harem stallions and drought severity were contributing factors. Our findings reveal that complex interactions between demography, climate, and harem size can emerge in social animals. Taken together, our results demonstrate that intrinsic population processes can regulate group size even in the presence of non‐stationary climatic conditions during periods of growth in human‐introduced, semi‐free ranging animal populations

Breeding in an agricultural landscape: conservation actions increase nest survival in a ground-nesting bird

Agricultural intensification has affected wildlife across Europe, triggering steep declines and regional extinctions of farmland birds. Effective conservation activities are essential for the preservation of biodiversity in an agricultural landscape, but current efforts have not succeeded in halting these declines. Here we investigate a ground-nesting shorebird, the collared pratincole Glareola pratincola, which has shifted its habitat use in Central Europe over the last 20 years from alkaline grasslands to intensively managed agricultural fields. We show that nesting success was different between three agricultural habitat types, with the highest nesting success in fallow lands and the lowest in row crops. Nesting success was also associated with the timing of breeding and breeding density, as nests produced early in the breeding season and those in high-breeding-density areas hatched more successfully than those produced later in the season and at low density. We implemented direct conservation measures including marking nests and negotiating with farmers to avoid cultivating the field between nest markers, controlling nest predators and, most recently, creating suitable nesting sites and foraging areas for pratincoles. As a result of these conservation actions, nest survival increased from 11.2% to 83.5% and the size of the breeding population increased from 13 to 56 pairs during 2012–2021. Thus, we show that agricultural landscapes can continue to provide suitable habitats, and targeted conservation actions have the potential to reverse the declines of farmland species