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The loss of biodiversity on our planet is partly due to the presence and spread of alien invasive species. Once an invasive species has established in a new habitat, it can alter the structure and function of the ecosystem to such an extent that it has an impact even after removal, making it very difficult to control and eradicate. Ecological restoration, when carried out in an effective and sustainable way, contributes to biodiversity conservation and climate change mitigation, resilience and adaptation, and has proven to be an effective method of controlling invasive species. At the same time, the presence of invasive species in the landscape can compromise restoration objectives. The aim of this study is to assess how the abundance of annual and perennial invasive species varies with location, direction and distance around the restoration site, and which factors should be considered when planning restoration interventions.

Seeds of plant species are often dispersed unintentionally on our clothes, which thanks to the increasing mobility of people, can be important events in the process of biological invasions. Researchers from the HUN-REN Centre for Ecological Research, ‘Lendület’ Seed Ecology Research Group, investigated this topic, and published their results in the D1-ranked scientific journal Journal of Environmental Management. This study provides critical insights into the unintentional spread of plant species through human-vectored dispersal via clothing, a pathway that has received limited attention so far. Their findings show that most seeds remain viable after typical household washing, even at common temperatures and a wide range of detergent types, highlighting a largely overlooked vector of plant dispersal. Since most of the plants that are capable of cloth-dispersal are weeds and invasive species, the results have important implications for invasion control. They emphasize the need for targeted biosecurity measures, especially among those working outdoors, to mitigate the spread of invasive species. The results also offer actionable strategies for environmental management by integrating behavioural changes and public awareness to reduce the environmental impact of human-vectored dispersal. According to their questionnaire survey, raising awareness is especially important for nature conservation professionals who are among the most important potential vectors.

Citation of the paper:

Lukács, K., Kiss, R., Tóth, Á., Godó, L., Deák, B., Valkó, O. (2025): Effects of laundry washing on germination of cloth-dispersed seeds depends on washing intensity not on detergent type. Journal of Environmental Management 375: 124345.

Invasive mosquito species already established in Hungary can pose a significant threat to human and animal health due to their potential role in the pathogen transmission. Researchers from the HUN-REN Ecological Research Centre and the University of Pécs, part of the Invasion Biology Division of the National Laboratory for Health Security, and ELTE have published their results in the D1-ranked scientific journal ‘Journal of Pest Science’. In this study the researchers evaluated the effect of environmental factors reflecting climate, habitat type, food supply, traffic, and interspecific competition on the distribution of three invasive tiger mosquito species in Hungary. They trained species distribution models using citizen science observations and then predicted the potential distribution of the species. The researchers uncovered species-specific patterns and found that different predictor sets were selected for the three different species, however, only predictions for Asian tiger mosquito could be validated with direct trapping data. They concluded that citizen science informed distribution maps can be used to identify environmental predictors that determine the spread of invasive mosquitoes.

Researchers of the National Laboratory for Health Security’s Mosquito Monitor program created a new laboratory to breed invasive mosquitoes and to study their acoustic ecology. Adult individuals of the tiger mosquito (Aedes albopictus), which is bred here, feed on nectar in the wild, but get sugar-water instead in the lab. In order to produce eggs, females are fed with sterile cow blood via the Hemotek system, a device designed specifically for feeding blood sucking insects. The lab follows the arthropod containment guidelines, in order to prevent any potential escapes.

The researchers built a soundproof box with camera and microphones inside, with which they are able to record high quality footage even of low sound intensity. Audio recordings can be analysed using a specialised software, thus several acoustic variables can be extracted. The variation in sound can also be linked to the mosquito behaviour, recorded using the video camera.

Two projects are currently running in the lab. The first one is the identification of mosquito species based on sound, with the help of artificial intelligence. The second project aims to better understand the acoustic communication of the female and male tiger mosquitoes during the mating sequence. In some other mosquito species it has been shown that the male and female converge toward the same sound frequency right before mating together. This capacity of changing the flying sound and to adjust to the potential mate could play a significant role in mate choice and sexual selection. A better understanding of this phenomenon could help develop efficient techniques in mosquito control.

Ground-nesting bees are highly sensitive to changes in vegetation, flower supply and soil properties caused by plant invasions. The direct and indirect effects of twelve alien invasive plant species were investigated under field conditions. Invasion generally reduced flower resources, increased vegetation height and affected some soil properties. While invasion had a negative effect and the amount and diversity of flowers had a positive effect on ground-nesting bees, but no relationship was found between the soil properties and bees. Our findings suggest that it would be worth exploring the issue in more depth, for example using more specific field methods to explore the role of additional soil parameters. Our present publication is a first step towards future research exploring the role of soil properties on bees.

Biological invasions are a growing challenge around the world. Meanwhile, it is now widely recognised and acknowledged that indigenous peoples’ territories play a key role in global biodiversity conservation. On the one hand, their land-use practices are often more nature-friendly than conventional land-use practices, and on the other hand, their territories, like protected areas, are in more remote locations, away from urbanisation and transport infrastructure. Our article, for the first time in the world, examined the extent to which indigenous peoples’ territories are threatened by invasive species compared to the rest of the world’s landscapes. We used our previously published global map. We calculate that, on average, there are 30% fewer invasive species in indigenous peoples’ landscapes than in other parts of the world. If we take into account differences in sampling intensity, distance of sites from roads, major land cover types, etc., the difference is reduced but remains significant. In the rare cases where the number of invasive species was higher in the indigenous areas, propagule pressure from neighbouring, e.g. urban areas, could be assumed as a cause.
Our article is part of a series of articles examining the contribution that indigenous peoples’ territories can make to the maintenance of the world’s natural heritage.

Related publications:

Fa, JA, Watson, JEM, Leiper, I., Potapov, Evans, Burgess, Molnár, Z., Fernández-Llamazares, Duncan, Wang, Austin, Jonas, Robinson, Malmer, Zander, Jackson, Ellis, Brondizio, Garnett (2020): Importance of Indigenous Peoples’ lands for the conservation of intact forest landscapes. Frontiers in Ecology and the Environment 18(3), 135-140.
Garnett, S.T., Burgess, N.D., Fa J.E., Fernández-Llamazares, Á., Molnár, Zs., Robinson, C.J., Watson, J.E.M., Zander, K.K. et al. (2018): A spatial overview of the global importance of Indigenous lands for conservation. Nature Sustainability 1: 369–374.
O’Bryan CJ, Garnett, ST, Fa, JE, Leiper, I., Rehbein, J, Fernández-Llamazares, Á, Jackson, MV, Jonas, HD, Brondizio, ES, Burgess, ND, Robinson, CJ, Zander, KK, Molnár, Z, Venter, O, Watson, JEM (2021): The importance of indigenous peoples’ lands for the conservation of terrestrial mammals. Conservation Biology, 35: 1002-1008.
Seebens, H., Niamir, A., Essl, F., Garnett, S.T., Kumagai, J.A., Molnár, Zs., Saeedis, H., Meyerson, L.A. (2024): Biological invasions on Indigenous peoples’ lands. Nature Sustainability (nyomdában) https://doi.org/10.1038/s41893-024-01361-3

The invasion of North American sand dropseed (Sporobolus cryptandrus) in Hungary mainly threatens vulnerable open sandy grasslands. As there is already considerable field experience and research on the species in Hungary, and as this has shown that we are facing a very serious problem, it has become necessary to organise a large-scale professional meeting to discuss the most pressing issues of the invasion of sand prairie grass in Hungary.
On 27 March 2024, the HUN-REN Ecological Research Centre, Experimental Vegetation Ecology Research Group and the Kiskunság National Park Directorate organised this professional meeting in Kecskemét. The event was attended by experts from the research centres (University of Debrecen, University of Sopron, University of Szeged and HUN-REN Ecology Research Centre) and the national parks concerned (Kiskunság NP and Hortobágy NP). The primary aim of the meeting was to establish a link between researchers and conservation practitioners.
The first session presented research on North American sand dropseed in Hungary. Dr. Csaba Tölgyesi talked about the possibilities of controlling prairie grass with semi-parasites and competitors, Dr. Attila Torma presented the effects of prairie grass on arthropod communities, while Dr. György Kröel-Dulay (the main organizer and moderator of the meeting) presented the results of the mapping of the species in the Kiskunság region and the long-term monitoring and experimental studies that have been initiated. In the next session, participants discussed in a moderated discussion how they see the invasion of prairie grass in the coming decades and what possible ways of control could be. The next session opened with a presentation by Attila Rigó, who described possible ways to collect coordinated occurrence data and discussed the possibility of involving the public (citizen science), followed by a talk by Dr. Eszter Tanács on the possible use of remote sensing methods in monitoring the spread of prairie grass in Hungary. Afterwards, Dr. Ferenc Sipos, Deputy Director of the KNP, presented the National Park’s experience with the species, from its ecology to the practical challenges of eradication. Finally, the participants attempted to synthesise the knowledge gained so far and agreed on the way forward.
As a result of the meeting, an informal “Sporobolus working group” was formed, and the participants agreed to discuss ongoing and planned research and results, and to report back to each other once a year in a similar meeting. They also drew up a list of the most important research tasks and identified the most important non-research tasks. The possibility to join the group is open to all, with the explicit aim of bringing together researchers and conservationists working on the species and coordinating research and conservation interventions.
Contact Attila Rigó (rigo.attila@ecolres.hu) and György Kröel-Dulay (kroel-dulay.gyorgy@ecolres.hu)

One of the research topics of the Pilis Forestry Systems Experiment is to investigate the effects of different silvicultural practices on understorey vegetation in an oak–hornbeam forest stand. In the experiment, interventions of two significantly different forest management modes were studied between 2014 and 2020. Three interventions modelled the conditions of the so-called clear-cut forest management applied in the largest area of Hungary: a cut area, a group of residual trees in the cut area, and a so-called cut stand where half of the trees were removed. In Hungary, the continuous cover forestry method is still only applied in a small area, one of the most important elements of it is the creation of a gap in the closed canopy by cutting a few trees. The continuous cover forestry mode was therefore modelled with gap cutting. In addition to the above interventions, the experiment also included a control area where no interventions were made. The effects of the five intervention types were observed in 6 replicates (blocks).
We studied how understorey attributes change in response to different forest management and how these responses change over time. Then we assessed the ability of treatments to maintain the forest character of the vegetation. One of the most important differences between the experimental sites was the behaviour of disturbance-tolerant and invasive species. The majority of indicator species associated with the cut areas were disturbance tolerant (Cirsium arvense, Calamagrostis epigeios) and invasive, light-demanding species (Erigeron annuus, Conyza canadensis, Solidago gigantea). None of these species were present in the area before the interventions. The disturbance-tolerant bushgrass (Calamagrostis epigeios) and the invasive giant goldenrod (Solidago gigantea) started to become more common in the areas after the third year of the interventions (2017). The goldenrod was dominant in only a few areas, but was still present in some areas six years after the interventions (2020). The average cover of bushgrass was 9% five years after the intervention and reached 25-50% in some of the cuttings. None of these species were present in the plots, and if some individuals appeared in one year, they disappeared the following year. Compared to the cuttings, the soil moisture and humidity were higher in the cuttings. These microclimatic factors were probably behind the phenomenon that the experimental stands retained the forest understory character better because they proved more resistant to disturbance and invasive species than the cuttings.
The study shows that areas managed under continuous cover forestry methods can be more resistant to disturbance-tolerant and invasive species than areas under clear-cut management, and that increasing the proportion of continuous cover forestry management in our country is important from both ecological and conservation perspectives.

Led by researchers from the University of Alberta in Canada, members of the CER ‘Lendület’ Seed Ecology Research Group also participated in an international study to find the key to the success of invasive grass species. The results of this research have recently been published in the journal Oikos. The three grass species studied were native species of Eurasian grasslands – smooth brome (Bromus inermis), narrow-leaved meadow-grass (Poa angustifolia) and crested wheat grass (Agropyron cristatum) – which are considered invasive species causing serious conservation problems on North American prairies. Our experiment sought to answer whether seed origin or soil-mediated effects contribute to the invasiveness of these three grass species. We collected seeds and soil from populations from non-native (Canada) and native (Hungary, Kazakhstan, Germany, Ukraine) ranges (47 populations in total), germinated seeds in all possible combinations (from their own population, from other populations in the native range, and on soil from invasive ranges) and compared the biomass of developing seedlings.
Although we have studied biologically and ecologically similar species, our results suggest that the key to success for each species is different, species-specific. In the case of the crested wheat grass, our results suggest that the species has become evolutionarily more successful since the invasion (i.e., larger plants have developed from seeds from Canadian populations, regardless of soil type) and that soil-mediated effects have contributed to its success (root biomass of plants was higher in soils from Canadian populations, regardless of seed origin). In the case of smooth brome, local adaptation may be the key to success. This means that within the invaded range, seeds from a given population developed the highest biomass in the soil of their own population, while smaller plants developed in soils from other Canadian populations. Overall, the study shows that the keys of success of invasive species are influenced by a number of factors, many of which act in concert and may reinforce each other. Targeted research on the key species of most conservation importance is therefore very important, as effective action against invasive species requires knowledge of the factors that determine their success.

In January 2024, the HUN-REN Ecological Research Centre’s Evolutionary Ecology Research Group launched a network of community science projects on conservation and ecology in Hungary. The SEEN (Social Engagement in Ecology Network) Conference, held in Tata on 18-19 January, aimed primarily to create a living link between Hungarian community science projects and the researchers working on them.
The community science method is about involving civilians at different stages of the scientific process. For example, in cases where researchers want to collect data from across the country on the occurrence of particular species, observations by civilians can multiply the effectiveness of the research. This can be particularly important in the case of invasive species, where up-to-date information on the distribution and abundance of species is of particular importance.

Several community science projects aimed at detecting and monitoring invasive species, such as ticks, mosquitoes or an ivy species, were presented at the SEEN conference. Several research groups from the Invasion Biology Division of the National Laboratory for Health Security were represented. In addition to the above-mentioned research on invasive ticks and mosquitoes, the research also covered alien plants escaping from gardens and an intensively spreading native species, the beaver. In this way, research into invasion biology has received considerable attention.
As well as presenting research, the conference focused on community science as a socially important method. Involving citizens in the scientific process is an opportunity to transfer knowledge, to raise awareness of ecological, health and social problems affecting our environment, and to increase trust in scientists and science. Last but not least, it can help to bridge the gap between scientists and society, which for many seems unbridgeable.