Biological Invasions最新文献

Managing invasive alien species (IAS) is a significant challenge for both ecological and socioeconomic systems. Our understanding of the role of information sources in stakeholders’ IAS management is elusive for the majority of insect invaders. We focused on the fall armyworm (FAW), Spodoptera frugiperda, one of the most damaging alien insects worldwide, to explore the role of information sources in farmers’ management of alien agricultural pests. We developed a theoretical framework containing three components and seven indicators, conducted extensive household questionnaires in the region bordering Myanmar, Laos, and Vietnam in southwestern China, and used quantitative descriptions, ordinal logistic regressions, and Mann–Whitney U-tests in statistical analyses. Our results showed that farmers had a generally low level of recognition ability, medium level of control ability, and high level of engagement initiative in FAW management, and farmers’ FAW management was significantly associated with socio-demographic variables. Farmers obtained FAW-relevant information from four sources with a high preference for training workshops and agricultural retail stores; further, training workshops played a more effective role than agricultural retail stores in farmers’ FAW management. Here, we show for the first time that training workshops are the most effective sources of information in farmers’ FAW management, and agricultural retail stores serve as necessary support. Future research could extend these conclusions by including socioeconomic mechanisms such as informational feedback loops and public-private partnerships among stakeholders. Our findings contribute to theoretical insights into the role of information sources in IAS control, and to optimized management of alien agricultural pests.

The intrusion of non-native species into freshwater ecosystems can lead to rapid shifts in fish community dynamics, posing significant threats to biodiversity and ecological stability. In this study, we examined the changes in the fish community within the Kerkini Reservoir, a Ramsar Site in Greece, influenced by the establishment of invasive fish species. Through standardized seasonal surveys conducted in 2007–2008 and 2023, we assessed changes in fish species composition, abundance, and functional traits. Our findings revealed a shift in dominance, with invasive species such as Gymnocephalus cernua emerging as key players in the reservoir's fish fauna. Moreover, high numbers of fish specimens and biomass were recorded, highlighting the reservoir’s high productivity. However, concerns arise regarding the ecological impacts of invasive species, particularly G. cernua, which exhibits traits associated with ecological disruption and competition with native species. A shift towards the dominance of species with shorter lifespans, smaller sizes and lower trophic levels was observed. In addition, the observed decline in native species abundance, coupled with poor ecological quality assessments, underscores the need for proactive management measures to preserve ecosystem integrity. This study contributes valuable insights into the ecological dynamics of a system considered a biodiversity hotspot. It also highlights the proliferation of invasive fish species as a primary driver and underscores the importance of ongoing monitoring and conservation efforts. However, future research is needed, focusing on further understanding the long-term effects of invasive species establishment and their implications for native fish populations and ecosystem functioning.

Most alpine ecosystems are subject to non-native species invasion as climate warms and human disturbance increases. Therefore, it is important to identify the main barriers and facilitators of alpine plant invasions. While there is much research in continental alpine areas, there is limited research in maritime environments, which have distinctive biological, edaphic and geomorphologic features due to the scarcity of snow in winter. Here, we examine the contribution of anthropogenic and biotic factors on non-native plant invasions in the alpine areas of lutruwita (Tasmania), Australia. Specifically, we test whether disturbances associated with roads and livestock grazing facilitate non-native plant invasion and if biotic resistance from native plants and wild grazing animals inhibits such invasion. We used floristic data from: a statewide database; data from long-term grazing exclosures, and data from paired quadrats on roadsides and natural vegetation. Our results showed that non-native plants were associated with roadside disturbance and livestock grazing, with the latter having a legacy effect of 50 years. The persistent effect of stock grazing was evident in the exclusion experiment monitored over 30 years, where non-native plants occurred sporadically in time and space. In contrast, we found that the presence of wild grazing mammals, complete vegetation cover and high native richness, restricted non-native plants, emphasizing the importance of biotic resistance in controlling non-native plant invasions. These results indicate that livestock removal and road closure could be effective in reversing non-native plant invasion in this and other areas with wild vertebrate herbivores and high plant cover.

While conducting a landscape genomics study of invasive tammar wallabies (Notamacropus eugenii) in Aotearoa New Zealand we discovered that parma wallabies (N. parma) are also present in the North Island. This population has gone undetected for at least 30 years (and potentially for over a century), hidden amongst the morphologically similar tammar wallabies. The fact that an invasive wallaby species could remain undetected for so long, highlights the need for greater monitoring efforts for invasive species including genomic species identification.

Biological surveillance at an invasion front is hindered by low population densities and, among animals, high mobility of target species. Using the barred owl (Strix varia) invasion of western North American forests as a test case, we tested real-time autonomous recording units (the ecoPi, OekoFor GbR, Freiburg, Germany) by deploying them in an area known to be occupied by the target species. The ecoPi passively record audio, analyze it onboard with the BirdNET algorithm, and transmit audio clips with identifiable sounds via cellular network to a web interface where users can listen to audio to manually vet the results. We successfully detected and lethally removed three barred owls, demonstrating that real-time acoustic monitoring can be used to support rapid interventions at the forefront of an ongoing invasion in which proactive management may be essential to the protection of an iconic native species, the spotted owl (S. occidentalis). This approach has the potential to make a significant contribution to global biodiversity conservation efforts by massively increasing the speed at which biological invasions by acoustically active species, and other time-sensitive conservation challenges, can be managed.

If an animal’s size, age and/or sex influence its vulnerability to an invasive species, the arrival of such an invader can cause rapid changes in the population demography of an affected species. We studied free-ranging varanid lizards (Yellow-spotted monitors, Varanus panoptes) at a site in tropical Australia during the influx of fatally toxic cane toads, Rhinella marina. Mortality was inferred from shifts in population structure, as well as the survival rates (time to death) of 107 radio-tracked lizards. Of 57 deaths whose cause was unambiguous, 32 were due to fatal poisoning by ingesting a cane toad; the other 25 lizards were consumed by pythons. Size and age structure shifted between years, such that the population post-invasion was dominated by smaller, younger lizards, and by females rather than males. Radiotelemetric monitoring confirmed that survival rates were reduced more in males than in females in the post-toad year, with males most at risk late in the dry-season, when food was scarce and females were nesting rather than foraging. Pythons disproportionately consumed larger female lizards during the nesting season. Toad-induced poisoning of adult male varanids (which are larger and bolder than females) likely produced a population that was more resilient to toad impact, but less easily surveyed by conventional techniques.

The shrub, Robinia hispida L., commonly known as the bristly locust, is a native to southeastern United States. It has, however, expanded its range within North America, and established invasive native-alien populations in several American states and Canada. Outside of North America, R. hispida has been introduced to Europe and Asia, where it has naturalised and is considered invasive. Notably, the presence of this shrub has never been reported outside of cultivation in Africa. Despite receiving little scientific attention compared to its congeneric species such as the global invader Robinia pseudoacacia L., R. hispida shares morphological and growth characteristics including rapid growth and a suckering habit. It occupies similar environmental niches in both native and introduced ranges, thriving in thin upland woodlands, woodland edges, thickets, fence rows, roadside embankments, banks of drainage canals, vacant lots, and overgrown waste areas. In South Africa, R. hispida was first recorded in a garden in Polokwane in 1986, while the first record outside of cultivation was near the town of Bethlehem in the Free State Province in 2023, and further surveys were conducted locating additional populations near the towns of Zastron and Clarens in 2024. The potential distribution of R. hispida in South Africa was modelled in MaxEnt using areas climatically representative of the species, based on the Koppen-Geiger climate classifications. The potential distribution includes areas of central South Africa, the east and south coast and the Mediterranean climates of the southern Cape. Management strategies suggested for R. hispida in South Africa, considering the small size of the populations, should include eradication efforts using mechanical and chemical means, followed by continuous monitoring to prevent re-emergence.

We aimed to investigate the presence of the copepod Pseudodiaptomus trihamatus in an estuary in Northeastern Brazil, from a long-term perspective (1987–2023), and its distribution in other nearby estuaries, after 30 years of invasion, especially considering its impacts on native congeneric species. We tested the following hypotheses: (i) The abundance of P. trihamatus increases over time and the abundance of native species decreases; (ii) The β diversity decreases over time; (iii) Copepod composition and β diversity differs over time. The study was carried out in six estuarines systems in Pernambuco, in the Northeastern Brazil. The investigation of long-term variation (1987–2023) was based on the Capibaribe River Estuarine System (CRES), while for the spatial variation (2020–2021), six estuarine systems were considered. We observed that P. trihamatus has occurred in CRES since 1991, 10 years before the first record of the species in Pernambuco. The abundance of P. trihamatus did not increase over time. Furthermore, β diversity increased over time, showing that the presence of P. trihamatus did not cause biotic homogenization through loss of biodiversity. In the spatial variation (2020–2021), we found P. trihamatus in four of the estuaries and was it the third most representative species of the family. The occurrence of P. trihamatus did not significantly affect the Pseudodiaptomidae family and the copepod assemblage, for either long-term or spatial variation. The undetected or negligible impact of P. trihamatus need to be monitored, to prevent a sleeper population from becoming highly abundant and, perhaps, disruptive in this region of Brazil.

Protected areas are key to global biodiversity conservation efforts. Yet, most protected areas globally face threats of biological invasions either by invasive non-native species established within the protected area or by the imminent establishment of invasive non-native species established in the surrounding landscapes. In face of growing biological invasions, protected area managers must be able to set prevention and control priorities for invasive non-native species management. In this study, we developed a new methodological approach to identify which protected areas should be prioritized for prevention and early detection and which should be prioritized for control of biological invasions. Our methodological approach analyzes the occurrence of invasive species within and around the protected areas and weights the influence of multiple existing pathways to calculate the probability of introduction of invasive species and colonization pressure for each protected area. We evaluated our priority setting model in 280 terrestrial and 42 marine protected areas in Brazil. For the terrestrial protected areas, 84 were classified as priority for prevention and early detection and 124 were classified as priority for control of biological invasions. For the marine protected areas, 25 were classified as priority for prevention and early detection and seven were classified as priority for control of biological invasions. Human population density and percentage of pasture cover surrounding the protected area were the most important factors for priority setting in terrestrial protected areas whereas number of aquiculture activities, density of waterways, distance to ports, distance to oil platforms, and distance from sinking points were the most important factors for priority setting in marine protected areas. In conclusion, the framework presented here provides an objective methodology for managers and stakeholders to decide where to invest their limited resources available for management of biological invasions in protected areas.

Broad infestations of invasive, non-native vegetation have transformed wetlands around the world. Ludwigia hexapetala is a widespread, amphibious invasive plant with a creeping growth habit in open water and an erect growth habit in terrestrial habitats. In the upper San Francisco Estuary of California, L. hexapetala is increasingly terrestrializing into marshes and this expansion may be facilitated by allelopathy. We conducted the first field-based study on L. hexapetala allelopathy to determine whether (1) three allelochemicals known to be exuded by L. hexapetala are expressed in situ, (2) the allelochemicals are detectable in leaves, soil, and water, and (3) allelopathic expression varies by season, salinity, and growth habit (open water “patch” vs. terrestrial marsh “interface” locations). Water, soil, and L. hexapetala leaves were collected in two freshwater sites and two oligohaline sites in the upper San Francisco Estuary in summer 2021, fall 2021, and spring 2022. Myricitrin and quercitrin, known allelochemicals, and salipurposid, a newly identified polyphenol, were detected in water, soil, and leaves. There were significant differences in allelochemical concentrations under fresh versus oligohaline conditions in water and soil, but not leaves. All three allelochemicals generally had higher concentrations in patch versus interface locations, suggesting that L. hexapetala allelopathy plays a greater competitive role in open water than terrestrial habitats. Leaf concentrations of each allelochemical varied seasonally; however, both myricitrin and salipurposid had heightened concentrations in spring. These results suggest that herbicide application in early spring may be most effective in controlling L. hexapetala terrestrialization from open water to marshes.