Biological Invasions最新文献

In agricultural systems, responsive management can mitigate the effects of risk and uncertainty by facilitating adaptation to changing conditions. A tool for evaluating management systems while accounting for risk and uncertainty is Probabilistic Cost Benefit Analysis (PCBA). This study used PCBA to contrast a new responsive disease management strategy against an existing prescriptive strategy. Fungicide application to prevent myrtle rust (MR) in NZ plant nurseries was used as a case study to test if the expected benefits of the responsive strategy justified the investment in potentially more frequent and costlier disease control. A MR risk generator was used to simulate disease progression. Empirical MR risk distribution functions were sampled to stochastically compare net benefits across scenarios, highlighting the potential impact of infrequent but significant disease incursions. Our results showed that the risk-based strategy was more effective at controlling the disease, especially for susceptible myrtle species in high-risk locations. The findings highlighted the essential role of fungicides in propagating highly MR-susceptible species, and that disease management, when responsive to risk, enhanced the efficiency of fungicide use. The Responsive strategy is discussed as an effective management option for nurseries under uncertainty of significant MR incursions. However, in less risky scenarios, the benefits of the responsive strategy were moderate, and operational considerations may favour the standard calendar-based approach. In such cases, the method provided here can help estimate the appropriate fungicide application interval and the associated MR risk.

Protected areas are expected to harbour fewer invasive plants due to the absence of anthropogenic disturbance and greater resistance of natural vegetation to invasion. Our study aimed to quantify the impacts of selected invasive plants on native plant species richness, diversity, and composition in five protected areas of Nepal spread across ~ 3403 km² at the Himalayan foothill. Lantana camara, Mikania micrantha, and Parthenium hysterophorus were selected as target species based on their abundance in the study area. For each species, 30 pairs of invaded and uninvaded plots of 10 × 10 m were sampled to record the presence and covers of all vascular plants. The impacts of invaders on species diversity were analyzed using linear mixed-effect models, those on plant community composition by direct gradient ordination. The analysis of merged data, including all studied invaders, showed that the invasions reduced native species richness and diversity, which decreased to less than half of the values recorded in uninvaded plots. Similarly, each of the three species had a significant negative impact on native species richness and diversity when tested separately, with M. micrantha having the greatest impact, followed by P. hysterophorus and L. camara. In addition, the invasion by L. camara explained the greatest percentage of variation in the species composition of the invasive species studied. The results support the invasion meltdown theory, as the invasion promoted the presence of other alien species in the invaded plots.

Invasive earthworms create widespread ecological changes after they are introduced. Non-native earthworms are transported mainly through anthropogenically-mediated activities, including fishing, agriculture, horticulture, and development. Here, we review the ways in which non-native earthworms are transported to new environments. Our conceptual framework involves invasion filters (human activities filter and climate & edaphic filter) that constrain which non-native earthworm species are transported within specific contexts. Differences in earthworms’ ecological behaviors, life cycle, and physiological tolerance of environmental conditions influence which species are transported and which regions can successfully be invaded. Within the human activities filter, we utilize the six invasion pathways that follow a continuum of human intention as laid out by Hulme et al. (J Appl Ecol 45(2):403–414, 2008). Five of these pathways are associated with human activity. Of these, the release, escape, and contaminant pathways are associated with commodities, and the stowaway plus corridor pathways with transportation infrastructure. Major human activities that transport invasive earthworms include the discarding of fishing bait, agriculture, composting and horticulture, and development (e.g., the construction of roads, trails, houses, or campgrounds), but the magnitudes that specific activities transport earthworms are vastly understudied. We conclude that more research needs to be conducted to understand the methods that transport non-native earthworms in order to slow their spread.

In the Great Plains region, the live bait industry relies on approved species of cultured and wild-harvested baitfish. The release of baitfish by anglers is prohibited in most locations, but angler compliance with these regulations can be low. Bait retailers can increase compliance with regulations by communicating with anglers about aquatic invasive species (AIS) risk and through their business practices. We conducted 66 telephone surveys with bait retailers in southeastern South Dakota from June to July 2023 to (1) characterize bait retailer practices that may influence AIS risk and (2) determine the extent and willingness of bait retailers to display educational materials to reduce AIS risk. Fathead minnows (Pimephales promelas) were the most sold species (96% of respondents), and most bait came from wholesale retailers (74%). However, 24% of bait retailers also occasionally bought from local bait harvesters. Non-advertised species were observed at least once in shipments by 35% of bait retailers, but retailers only encountered species they did not intend to order in 1% of their inspections. Regular inspections for non-advertised species in baitfish shipments were conducted by 74% of retailers. Most inspections occurred at the time of receiving a baitfish shipment (36%) or daily (36%). Bait retailers were interested in displaying provided AIS educational materials (80%), including posters and pamphlets (59%), stickers (41%), bait bags (39%), and keychains/boat key floats (36%). Displaying educational materials at bait retail locations may increase angler knowledge of AIS and compliance with bait disposal regulations.

Understanding societal interest in invasive species is crucial as greater public attention can support the success of conservation efforts. One of the main challenges in monitoring societal interest to support conservation is the absence of near-real-time indicators to track large-scale spatiotemporal dynamics of public attention. However, the digital revolution has opened up new opportunities to develop such indicators in support of invasive species research and management. Here, we aim to evaluate public awareness and interest in the invasive lionfish (Pterois miles) in the Mediterranean Sea and investigate spatiotemporal patterns of public interest in the species along its invasion front by using Google search volumes as a proxy for public attention. We implemented topic searches for the lionfish to download Google search volumes from 2013 to 2022 and used these data to test two hypotheses: (1) countries experiencing lionfish invasion exhibit higher public attention than those without lionfish, and (2) in invaded countries, public attention peaks around the arrival year, followed by a decline to baseline levels. Our study confirmed the first hypothesis, showing higher public attention in invaded countries. However, temporal patterns of attention did not fully align with the year of lionfish arrival, suggesting that the socio-political complexity of the region (e.g., cultural trends or internet accessibility), may be a key aspect to consider in future studies. Overall our study shows that digital data sources provide a unique opportunity to monitor social aspects of biological invasions with low associated costs and quick access to a great amount of data generated by internet users.

Invasive alien plants (IAPs) represent a major challenge to biodiversity and ecosystem functioning, especially those transformer species. Litter chemistry and decomposition rates are relevant factors to understand the invasion process due to its influence on nutrient cycling and ecosystem dynamics. Here, we present the results of a litterbag mesocosm comparing the decomposition dynamics of litter produced by two common IAPs (Acacia dealbata and Carports edulis) with similar amounts of native litter from invaded ecosystems (shrubland and coastal dunes invaded by A. dealbata and C. edulis, respectively), and how this different leaf litter origin further affects soil community function and the growth of seedlings of different native species. After 12 months of incubation, plant litter decayed at a rate of between 54 and 36% (C. edulis litter > dune litter and Shrub litter > A. dealbata litter) with slight changes in nutrient composition (C, N, C:N, and P content) at the end of the assay. Whereas the effect of the litterbag content (native vs. non-native plant litter) was rather limited, the incubation time significantly affected physico-chemical parameters. Thus, extracellular enzymatic activities (EAs, including acid and basic phosphatase, β-glucosidase, urease) varied depending on the litterbag content (native and non-native) for both decomposing species (A. dealbata or C. edulis). The correspondence analysis (CA) based on the community level physiological profile (CLPPs) showed a similar trend of data clustering regardless of the IAP considered. In both cases, different decomposition times were more relevant than litter origin to discriminate the soil functional activity. Finally, seedlings of different native species were grown in soils previously used for the litter incubation experiment. Here, seedlings of native species growing in soils from the mesocosm (previously covered with native or invasive litter) showed a species-dependent response. At the end of the assay, slight differences were found between the invasive and native plant litter. The results of the decomposition rates between litter of different origin, the effect of litter origin on soil nutrient content, on extracellular EAs, on the functional profile of soil communities, and also on the performance of native seedlings can be considered as limited. These results suggest that litter chemistry might not be as relevant as previously suggested—at least not relevant to explain ecosystem-level alterations—while highlighting the importance of assessing invasion thresholds rather than litter chemical composition.

Knowledge on the distribution of non-native fishes is critical to assess the current status of biological invasions and prevent further spread and impacts. This study aims to synthesize current distributional data of the non-native catfish, Hemibagrus wyckioides, an emerging invader in Peninsular Malaysia. We collected occurrence data from Facebook groups created by anglers and freshwater fish enthusiasts, which were used to map the distribution of the species. A total of 106 occurrences of H. wyckioides were recorded in five states, with three major invasion hotspots identified—Selangor, Pahang and Perak. Given the scarcity of distributional data for this species within the published literature, social media platforms provided invaluable information on the current distribution of this emerging invader, highlighting their potential utility in early detection and monitoring of poorly-known non-native fishes.

Non-native, invasive plants are increasingly common in Eastern North American forests, but their impact on soil fungi remains unclear. We used DNA metabarcoding to investigate the effects of nativity, plant mycorrhizal type and soil factors on root-associated fungal communities. We focused on understory woody plants in a deciduous forest tract in central New York state, and included three plant types, invasive arbuscular mycorrhizal (AM), native AM, and native ectomycorrhizal (EM), each represented by 3–5 species. We found lower fungal operational taxonomic unit (OTU) diversity in EM than AM plants, but no OTU diversity difference between native and invasive AM species. Pathogen OTU richness and relative abundance were not distinct between plant types. OTU composition was influenced by host mycorrhizal type and by AM plant nativity, with mycorrhizal fungi being important drivers in both cases. The relationships of soil characteristics (e.g., pH) with OTU composition were independent of plant nativity and mycorrhizal type. Specific root length of native AM species was lower than that of invasive AM plants, while EM plants were intermediate. Irrespective of plant type, OTU composition was distinct among plant species, particularly in fungal communities associated with the invader Rhamnus cathartica. These results suggest that invasive AM plants may shift fungal composition relative to native AM and EM plants, with potential long-term consequences for soil biodiversity.

The Galápagos Archipelago, a unique and ever-changing natural experiment, has seen an increase in introduced species due to increased human mobility. Among these, introduced ants represent a significant concern given their potential to reach high densities and displace native fauna. This study analyzed the diet of six Galápagos lava lizard species (Microlophus spp.) through the examination of 177 fecal pellets collected over two seasons. We identified 7084 food items across 39 categories, with ants predominating, making up 65% of occurrences and 90% of the total abundance. Notably, introduced ants constituted 57.1% of these occurrences and 79.4% of the total abundance, indicating a significant prevalence of introduced prey. This finding suggests a substantial shift in the islands’ ecological dynamics away from their natural state (i.e., without introduced ants). We also explore the dietary breadth of each lizard species and their similarity. Finally, we discuss the possible direct and indirect effects of the high prevalence of ants in the diet of Galápagos lava lizards, report interesting findings in their diet, and advocate for the use of feces as a non-invasive method to monitor for invasive ants. Our study highlights the ecological changes underway on these islands, underscoring the need for targeted conservation strategies to mitigate the impact of invasive species and preserve Galápagos biodiversity.