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Identifying areas at high risk of invasion is considered an important step for prioritization of phytosanitary measures to prevent biological invasions. Because climate change is likely to affect species' habitat suitability, ideally this should be considered in invasion risk assessments.We evaluated whether climate change affects habitat suitability and invasion risk of eight potentially invasive Eucalyptus pests in Brazil: Eucalyptolyma maideni, Mnesampela privata, Ophelimus maskelli, Orgyia postica, Paropsis atomaria, Paropsisterna beata, Paropsisterna cloelia and Trachymela sloanei.The shifts in the distribution range varied depending on the species, year and climate change scenario. While a decrease in the distribution range was predicted for four species, an increase was predicted for two species. Moreover, a decrease and/or increase in distribution depending on the climate change scenario was predicted for two species.Increases in invasion risk were predicted in major Eucalyptus‐producing areas near international airports and high cargo volume seaports.Our study provides an important contribution to knowledge on the effects of climate change on the distribution of eight potentially invasive Eucalyptus pests and reinforces the need to consider the changes in species' habitat suitability in invasion risk assessments. [ABSTRACT FROM AUTHOR]

Biological invasions are a major environmental challenge today. Interactions between invasive and native species can significantly shape community structures, influencing coexistence, diversity and functional composition of species. The subtropical Atlantic Forest in southern Brazil, a recognized biodiversity hotspot, provides a unique setting to study these interactions, given its vulnerability to alien tree invasions.Our study sought to elucidate the impacts of such invasions on this fragile ecosystem by addressing key questions: (1) How are tree community diversity patterns affected by the abundance of invading alien tree species? (2) What are the patterns of coexistence between native and alien invasive trees? (3) Is the functional composition of the forests altered by the abundance of invasive trees?To address these questions, we compiled data on the abundance and functional traits of native and invasive trees. We determined the diversity patterns and functional composition of plots with different degrees of invasion. These data were analysed using generalized linear mixed models, principal component analysis and a coexistence index.In plots with a higher abundance of invasive trees, there was a significant decrease in the taxonomic and functional richness (FRic) of native species. Furthermore, we observed that invasive alien trees coexisted with native species, and as the abundance of invasive trees increased, the native community‐weighted mean of the leaf area (LA) and specific leaf area (SLA) decreased.In conclusion, within the subtropical Atlantic Forest areas of southern Brazil, our findings highlight that the abundance of invasive trees adversely affects the taxonomic and FRic of native species. Furthermore, while invasive alien trees were found to coexist with native species, increased invasive abundance corresponded to a reduction in the LA and the SLA of the native community. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The soybean stem fly, Melanagromyza sojae (Zehntner) (Diptera: Agromyzidae), is an example of an insect pest with a restricted distribution that in the last few decades has been spreading to regions beyond its native range and causing economic losses. We evaluated whether M. sojae shifted its niche during biological invasion and used ecological niche models to estimate its global distribution under current and future climate conditions. In addition, we assessed whether the soybean stem fly represents a risk for major soybean‐producing countries, using Brazil as an example. Our analyses suggest that M. sojae has expanded its niche to new environments. Suitable habitats were predicted in all continents, including regions where this species has not yet been reported. Several soybean‐producing countries and all Brazilian growing areas are within the suitable ranges estimated for M. sojae. Also, most areas estimated as suitable under current climate conditions will remain so until at least 2080. These findings are important for invasion risk assessments aiming to prevent the spread of this species to major soybean‐producing areas. [ABSTRACT FROM AUTHOR]

Recognising which life‐history factors can potentially explain the success of biological invasions is essential to understand why certain exotic species are more successful to invade a given system than others, and also to better predict invasion outcomes. We focused on the three most planted pine tree species in Southern Brazil – Pinus elliottii, P. caribaea and P. oocarpa – as a natural system to test the hypothesis that some key vital attributes – fecundity (number of seeds produced), seed viability, germinability, seedling growth vigour (biomass and stem length) – could be driving the greater invasion of P. elliottii in the region. We collected seeds of P. elliottii var. elliottii, P. caribaea subsp. hondurensis and P. oocarpa in two sites of similar climate and soil in the Cerrado biodiversity hotspot. Seeds were tested for viability and germinability, and seed production was estimated. Under laboratory conditions, we evaluated seedling survival, stem and root development, biomass production and mortality for each species. Although P. elliottii is regarded as the most successful invasive pine species in the Cerrado, it did not outperform the other pines in terms of seed viability, germinability and seedling survival, and it had the slowest growth. P. elliottii did produce, however, at least twice as many seeds as the other species. P. caribaea revealed high seed viability and seedling survival, the fastest seedling development, but low seed production. P. oocarpa showed the lowest seed viability, but fast root growth and very low seedling mortality. Our results suggest seed production is a key factor for P. elliottii invasion success. However, given the strong performance of P. caribaea and P. oocarpa for germinability and growth, we emphasise the risk of both species also becoming successful invaders in the Cerrado. We highlight the need for constant monitoring of emerging pine individuals in native ecosystems to avoid future invasions. [ABSTRACT FROM AUTHOR]

We evaluated the fish composition and ecological attributes of the ichthyofauna collected in a limnological zone of the Taquaruçu Reservoir, lower Paranapanema River. Information about the fish community was updated when compared to the previous study (2006). Non-metric multidimensional scaling (NMDS) showed differences in species composition between periods and community weighted means (CWMs) exhibited changes in functional composition over time. Four functional indices were used in the principal coordinate analysis (PcoA) to measure changes in the functional space of species, whereas functional β-diversity inspected differences in the traits composition between the periods. 1,203 individuals were sampled of 43 species, being 16 non-native and 14 new records. Compared to 2006, 27 species were absent, most of them native to Loricariidae and Anostomidae, while Curimatidae and Pimelodidae decreased in abundance. Functional indexes showed a reduction in functional diversity, whereas new species records exhibited functional redundancy. It might have occurred a simplification of the fish community over time, excluding the migratory and specialists species such as the herbivores and detritivores. Accordingly, we concluded that the ichthyofauna of the Taquaruçu Reservoir might have been undergoing a process towards biotic homogenization. [ABSTRACT FROM AUTHOR]

Alterations in the hydrologic regime downstream from hydroelectric dams create a high invasibility to non-native species. This study aims to analyze the establishment of non-native Metynnis lippincottianus downstream of the Xingó Dam, lower São Francisco River, Brazil. Adults in reproduction were found throughout the study. Gonadosomatic index was higher in the reproductive phases and the species produces a large number of small oocytes. Hydrometric level and water flow data after the construction of Xingó Dam showed decrease in both parameters, facilitating the establishment of M. lippincottianus. Management actions are suggested to reduce the threat on the native biota. [ABSTRACT FROM AUTHOR]

Tubastraea tagusensis and T. coccinea (Scleractinia: Dendrophylliidae) are two corals that have invaded and impacted the southwest Atlantic since the 1980s. Here, we investigated experimentally the use of plastic and raffia sheets, simulating the use of wraps, as an effective method to kill the invasive corals. We showed that by seven days all polyps of the invasive corals were dead in both treatments, probably from lack of oxygen, food and/or due to physical attrition with the wraps. Tubastraea tagusensis was more resistant than T. coccinea, probably due to its different form. The use of plastic sheets was found to be more efficient for killing but raffia was easier to manipulate underwater and allowed an extended period for decomposition of the corals tissues. The use of wraps was demonstrated to be an efficient way of killing and may be added to the management toolbox for the control and eradication of Tubastraea spp. along with fresh water treatment and manual removal. [ABSTRACT FROM AUTHOR]

The Brazilian Atlantic forest has been reduced to a small fraction of its original area, with most remaining fragments being small and surrounded by anthropogenic matrices. This degree of disturbance, together with the increasing sprawl of cities towards the rural zone, greatly facilitates the entrance of domestic animals into these remnants. We used camera traps to compare the abundances of the domestic dog with a similarly sized native carnivore, the ocelot, in a 957-ha reserve of the Brazilian Atlantic forest in a landscape largely composed by pastures and agriculture. The dog was the most recorded species among all 17 mammal species 'captured' by the cameras. Dog abundance (32-38 dogs) and density (0.812-1.813 dogs/km2) were significantly higher than that of the ocelot (n=2 ocelots; density=0.158-0.347 ocelots/km2). Although our result is restricted to a single study site, it is supported by an increasing number of recent studies, which have detected dogs inside other Atlantic forest reserves. Our study suggests, therefore, that this invasion might be more widespread than generally thought. The presence of the domestic dog is a threat to native fauna and constitutes an important edge effect of human presence at the rural zone. [ABSTRACT FROM AUTHOR]