Remoteness promotes biological invasions on islands worldwide

One of the best-known general patterns in island biogeography is the species–isolation relationship (SIR), a decrease in the number of native species with increasing island isolation that is linked to lower rates of natural dispersal and colonization on remote oceanic islands. However, during recent centuries, the anthropogenic introduction of alien species has increasingly gained importance and altered the composition and richness of island species pools. We analyzed a large dataset for alien and native plants, ants, reptiles, mammals, and birds on 257 (sub) tropical islands, and showed that, except for birds, the number of naturalized alien species increases with isolation for all taxa, a pattern that is opposite to the negative SIR of native species. We argue that the reversal of the SIR for alien species is driven by an increase in island invasibility due to reduced diversity and increased ecological naiveté of native biota on the more remote islands.

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Alien Plants are Less Palatable to Pest Herbivores than Native Plants: Evidence from Cafeteria Experiments in Search of Suitable Plant Species to Restore Degraded Ecosystems

Ekológia (Bratislava) ◽

10.2478/eko-2021-0003 ◽

2021 ◽

Vol 40 (1) ◽

pp. 16-24

Author(s):

Mouldi Gamoun ◽

Mounir Louhaichi

Keyword(s):

Alien Species ◽

Plant Species ◽

Native Species ◽

Native Plants ◽

Feeding Preference ◽

Alien Plants ◽

General Tendency ◽

Native Plant ◽

Evolutionary Potential ◽

Wide Range

Abstract Nowadays, the ecology and evolutionary potential of alien species are the subjects of several ecological studies. The goal of this study was to compare the feeding preference of Arion ater on seedlings and leaves of alien and native plant species. Seedlings of three native species and one alien species were offered to slugs individually and in combination. Afterward, leaf discs from the native and alien species collected from the same source site of slug’s habitat were offered individually and in combination for slugs. When the new plant emerges, it constitutes a generous source of potential food and slugs would even feed on seedlings, which are not particularly palatable. Nonetheless, when given a choice, slug often preferentially feeds on some food items while ignoring others. Alien plants are more resistant to herbivory than native plants. There is a general tendency for alien species to be less palatable than native species. In general, slugs may eat a wide range of seedlings that are much more attractive than mature plants of the same species. Therefore, the native herbivores were found to attack native plants and promoted alien plants. Consequently, highly unacceptable alien species such as Eucalyptus globulus may play an important role in the restoration process.

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Effects of land-use change and related pressures on alien and native subsets of island communities

PLoS ONE ◽

10.1371/journal.pone.0227169 ◽

2020 ◽

Vol 15 (12) ◽

pp. e0227169

Author(s):

Katia Sánchez-Ortiz ◽

Kara J. M. Taylor ◽

Adriana De Palma ◽

Franz Essl ◽

Wayne Dawson ◽

...

Keyword(s):

Land Use ◽

Land Use Change ◽

Alien Species ◽

Native Species ◽

Species Number ◽

Land Uses ◽

Human Disturbances ◽

Biogeographic Patterns ◽

Island Species ◽

Using Data

Island species and habitats are particularly vulnerable to human disturbances, and anthropogenic changes are increasingly overwriting natural island biogeographic patterns. However, quantitative comparisons of how native and alien assemblages respond to human disturbances are scarce. Using data from 6,242 species of vertebrates, invertebrates and plants, from 7,718 sites on 81 islands, we model how land-use change, human population density and distance to the nearest road affect local assemblages of alien and native species on islands. We found that land-use change reduces both richness and abundance of native species, whereas the number and abundance of alien species are high in plantation forests and agricultural or urban sites. In contrast to the long-established pattern for native species (i.e., decline in species number with island isolation), more isolated islands have more alien species across most land uses than do less isolated islands. We show that alien species play a major role in the turnover of island assemblages: our models show that aliens outnumber natives among the species present at disturbed sites but absent from minimally-disturbed primary vegetation. Finally, we found a homogenization pattern for both native and alien assemblages across sites within most land uses. The declines of native species on islands in the face of human pressures, and the particular proneness to invasions of the more remote islands, highlight the need to reduce the intensity of human pressures on islands and to prevent the introduction and establishment of alien species.

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Changes in lowland dry-forest native and alien plant communities on Réunion Island (Indian Ocean) over 16 years

Botany ◽

10.1139/cjb-2015-0112 ◽

2015 ◽

Vol 93 (12) ◽

pp. 843-857 ◽

Cited By ~ 1

Author(s):

Marion Barbé ◽

Nicole J. Fenton ◽

Christophe Lavergne ◽

Timothée Le Péchon ◽

Cláudia Baider ◽

...

Keyword(s):

Alien Species ◽

Native Species ◽

Oceanic Islands ◽

Dry Forest ◽

Plant Succession ◽

Permanent Plots ◽

Alien Plant ◽

Forest Remnants ◽

Species Richness And Abundance ◽

High Level

Native floras of oceanic islands are among the most threatened on Earth. For example, only 1% of intact dry-forest ecosystems remain on Réunion, harbouring numerous endangered native species. Alien species invasion is one of the more important threats facing these ecosystems, as it has been hypothesized that, over time, the abundance of alien species will increase more than that of native species. To explore this, we studied floristic changes over a 16 year period (1995–2011) in six dry-forest remnants. Species richness and abundance increased for both alien and native species over this period, but at a significantly higher rate for the abundance of invasive alien plants. Despite this, Jaccard’s coefficient indicates a high level of similarity between the communities of 1995 and 2011. Also, the single site that benefited from invasive species management experienced the largest increase in native species, both in terms of specific richness and abundance. This study underlines the importance of permanent plots in studying the dynamics of invaded communities and in understanding plant succession. It also suggests a potential temporal persistence of island dry-forest communities, despite the expansion of alien species, and suggests the development of a new pathway in secondary succession where native and alien species coexist.

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Trait-Environment Relationships Reveal the Success of Alien Plants Invasiveness in an Urbanized Landscape

Plants ◽

10.3390/plants10081519 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1519

Author(s):

Reham F. El-Barougy ◽

Mohammed A. Dakhil ◽

Mohamed Abdelaal ◽

Ali El-Keblawy ◽

Louis-Félix Bersier

Keyword(s):

Alien Species ◽

Urban Areas ◽

Native Species ◽

Native Plants ◽

Plant Traits ◽

Species Traits ◽

Alien Plants ◽

Urbanization Gradient ◽

Soil Resources ◽

Species Groups

Urban areas are being affected by rapidly increasing human-made pressures that can strongly homogenize biodiversity, reduce habitat heterogeneity, and facilitate the invasion of alien species. One of the key concerns in invaded urban areas is comparing the trait–environment relationships between alien and native species, to determine the underlying causes of invasiveness. In the current study, we used a trait–environment dataset of 130 native plants and 33 alien plants, recorded in 100 plots covering 50 urban areas and 50 non-urban ones in an urbanization gradient in the arid mountainous Saint-Katherine protected area in Egypt. We measured eleven morphological plant traits for each plant species and ten environmental variables in each plot, including soil resources and human-made pressures, to construct trait–environment associations using a fourth-corner analysis. In addition, we measured the mean functional and phylogenetic distances between the two species groups along an urbanization gradient. Our results revealed strongly significant relationships of alien species traits with human-made pressures and soil resources in urban areas. However, in non-urban areas, alien species traits showed weak and non-significant associations with the environment. Simultaneously, native plants showed consistency in their trait–environment relationships in urban and non-urban areas. In line with these results, the functional and phylogenetic distances declined between the aliens and natives in urban areas, indicating biotic homogenization with increasing urbanization, and increased in non-urban areas, indicating greater divergence between the two species groups. Thereby, this study provided evidence that urbanization can reveal the plasticity of alien species and can also be the leading cause of homogenization in an arid urban area. Future urban studies should investigate the potential causes of taxonomic, genetic, and functional homogenization in species composition in formerly more diverse urbanized areas.

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Effects of land-use change and related pressures on alien and native subsets of island communities

10.1101/2019.12.16.878041 ◽

2019 ◽

Cited By ~ 1

Author(s):

Katia Sánchez-Ortiz ◽

Kara J. M. Taylor ◽

Adriana De Palma ◽

Franz Essl ◽

Wayne Dawson ◽

...

Keyword(s):

Land Use ◽

Land Use Change ◽

Alien Species ◽

Native Species ◽

Species Number ◽

Land Uses ◽

Human Disturbances ◽

Biogeographic Patterns ◽

Island Species ◽

Using Data

AbstractIsland species and habitats are particularly vulnerable to human disturbances, and anthropogenic changes are increasingly overwriting natural island biogeographic patterns. However, quantitative comparisons of how native and alien assemblages respond to human disturbances are scarce. Using data from 6,242 species of vertebrates, invertebrates and plants, from 7,718 sites on 81 islands, we model how land-use change, human population density and distance to the nearest road affect local assemblages of alien and native species on islands. We found that land-use change reduces both richness and abundance of native species, whereas the number and abundance of alien species are high in plantation forests and agricultural or urban sites. In contrast to the long-established pattern for native species (i.e., decline in species number with island isolation), more isolated islands have more alien species across most land uses than do less isolated islands. We show that alien species play a major role in the turnover of island assemblages: our models show that aliens outnumber natives among the species present at disturbed sites but absent from minimally-disturbed primary vegetation. Finally, we found a homogenization pattern for both native and alien assemblages across sites within most land uses. The declines of native species on islands in the face of human pressures, and the particular proneness to invasions of the more remote islands, highlight the need to reduce the intensity of human pressures on islands and to prevent the introduction and establishment of alien species.

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An eco-evolutionary rationale to distinguish alien and native status: why the dingo is a native species on mainland Australia

Australian Zoologist ◽

10.7882/az.2021.039 ◽

2021 ◽

Vol 41 (3) ◽

pp. 358-366

Author(s):

Peter B. Banks

Keyword(s):

Alien Species ◽

Introduced Species ◽

Native Species ◽

Genetic Basis ◽

Evolutionary Approach ◽

Range Transport ◽

The Status ◽

Local Species ◽

Natural Range ◽

Native Status

Distinguishing between whether a species is alien or native can be problematic, especially for introduced species that are long-established in new areas outside of their natural range. Transport by humans is the criterion for alien status used by many definitions, whereas arbitrary time since arrival to a location is often used to define native status. Here I propose an eco-evolutionary approach to distinguish between alien and native status and use this to resolve uncertainty in the status of the dingo in Australia. Dingoes were transported to mainland Australia by humans, but more than 4000 years ago, and dingoes now interbreed with feral domestic dogs. Legally, this mix of events has the dingo classified as native in some jurisdictions and alien in others. I suggest that native status for introduced species should be based on (1) whether the species has evolved in their new environment; (2) whether local species recognise and respond to them as they do towards deep endemic native species, and; (3) whether their impacts benchmark against those of a native species or are exaggerated like those of other alien species. Dingoes are behaviourally, reproductively and morphologically different to close ancestors from south-east Asia, and this difference has a genetic basis indicative of evolution in Australia. There is abundant evidence that native prey species on mainland Australia recognise and respond to them as a dangerous predator, which they are. But there is strong evidence that dingo impacts on prey are not exaggerated, with effect sizes from mensurative experiments similar to those of experiments on native predators rather than alien predators. These three lines of evidence suggest dingoes should be considered native to mainland Australia. I suggest this eco-evolutionary approach to defining native status can be helpful in resolving the often-heated debates about when an alien species becomes native.

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Alien Species vs. Native Species: From Community Ecology to Eco-Evolutionary Dynamics

10.20944/preprints201904.0189.v1 ◽

2019 ◽

Author(s):

Andersonn Silveira Prestes

Keyword(s):

Alien Species ◽

Exotic Species ◽

Native Species ◽

Evolutionary Dynamics ◽

Evolutionary Processes ◽

Native Communities ◽

Individualized Approach ◽

History Of ◽

Relationship Of ◽

The Relationship

The establishment and spread of exotic species is a contemporary major concern. Alien species may become invasive in their new habitat, leading to both/either environmental and/or economic impacts. I briefly reviewed the literature in the last decade about the relationship of exotic species and native communities. I identified that professionals usually approach the subject in two main points of view: (1) researchers tend to point out the impacts of alien species on entire communities, evaluating if the relationship is positive, negative or neutral; (2) they focus on the eco-evolutionary processes involved in the introductions, the dynamics of invasion, and individual study cases. When evaluating the response of introductions to entire communities, evidence seems to be ambiguous and may support positive, negative or neutral relationship, especially depending on the scale approached. The unique eco-evolutionary pathways of each introduction may be a great shortcoming in the searching for generalities. On the other hand, advances have been made in understanding the dynamics of invasion on different lineages through a more selective/individualized approach. I suggest that the dynamics of invasion might be studied through a perspective in which different eco-evolutionary processes, levels of organization (from gene to entire communities), the history of the organism(s) and time are taken into account. Individual cases might be compared in attempt to understand how the relationship exotic and native works and in the search for generalities.

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Golden jackal, a natural disperser or an invasive alien species in Slovakia? A summary within European context

Folia Oecologica ◽

10.2478/foecol-2020-0011 ◽

2020 ◽

Vol 47 (2) ◽

pp. 89-99

Author(s):

Peter Urban ◽

Nuno Guimarães ◽

Jozef Bučko

Keyword(s):

Alien Species ◽

Native Species ◽

Central And Eastern Europe ◽

Invasive Alien Species ◽

European Population ◽

Golden Jackal ◽

Game Species ◽

Fast Adaptation ◽

Natural Expansion ◽

Fast Increase

AbstractThis summary provides an overview of the golden jackal (Canis aureus) categorization in Europe with particular focus on its presence in Slovakia. The distribution range of this species in Europe has been expanding in recent decades. Currently, European population is in constant and fast increase, widening their ranges towards Central and Eastern Europe and more recently in some western countries. All over Europe, the categorization of the golden jackal status is discussed with some controversial. A recent genetic study helped to determine that golden jackals do not meet the established three criteria, which categorize a species as an invasive alien species. In Slovakia, golden jackals’ numbers grown considerably in the last decade and with an increasing of their distribution through the country it became a permanent species of the Slovak fauna. The only internal status is the hunting Act no. 274/2009, which classifies it as, game species. The fast adaptation and dispersion through Slovakia can be considered similar to the behaviour of an invasive species, as suggested in previous studies in Hungary. Based on widely accepted definitions, agreed under international legal instruments, it is quite clear that the term ‘Invasive Alien Species’ only encompasses non-native species specifically introduced by humans (intentionally or accidentally). Following this Invasive Alien Species terminology, golden jackals cannot be categorized as such in Slovakia. The natural expansion, the growing ranges, and the increase in numbers of the golden jackal in Slovakia in the last decades points to a need to improve the knowledge of the species.

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Dispersão de Espécie Exótica no Parque Nacional da Lagoa do Peixe e Seu Entorno (Dispersion of Exotic Vegetation Into and Around the Lagoa do Peixe National Park)

Revista Brasileira de Geografia Física ◽

10.26848/rbgf.v4i1.232694 ◽

2011 ◽

Vol 4 (1) ◽

pp. 33 ◽

Cited By ~ 1

Author(s):

Luana Portz ◽

Rogério Portantiollo Manzolli ◽

Dejanira Luderitz Saldanha ◽

Iran Carlos Stalliviere Correa

Keyword(s):

Native Species ◽

National Park ◽

Rio Grande ◽

Multispectral Images ◽

Rio Grande Do Sul ◽

Field Verification ◽

Exotic Vegetation ◽

Manual Classification ◽

Natural Dispersal ◽

Over Time

O Parque Nacional da Lagoa do Peixe está localizado no litoral sul do estado do Rio Grande do Sul. Dentre os conflitos existentes dentro da área do parque e no seu entorno, o aumento e a dispersão da vegetação exótica, vem gerando inúmeras discussões. Neste contexto o objetivo do presente trabalho foi identificar a distribuição espacial, ao longo do tempo, das áreas de plantações de Pinus sp. Para tanto foram utilizadas imagens multiespectrais de sensoriamento remoto (TM-Landsat 5), com datas entre 1986 e 2009, sendo realizada a classificação manual por meio da vetorização, verificação de campo e análise quantitativa e qualitativa dos resultados obtidos. O problema principal da dispersão natural de Pinus sp. é encontrado na margem da lagoa principal, margeada por banhados e por pinus, cuja dispersão espontânea está competindo com o crescimento da vegetação natural e alterando o cenário típico da região. De 1986, data de criação do parque, até hoje a área de pinus, no entorno desta lagoa, cresceu de 61 para 252 ha. Este aumento da área de ocorrência de Pinus sp, em mais de 4 vezes, torna necessária a sua extração, a fim de preservar as espécies nativas da região, bem como a diversidade biológica a ela associada. A expansão da silvicultura é preocupante, pois assumiu uma grande proporção em área, não se encontrando ações que indiquem uma desaceleração deste processo. Além de diminuir o valor estético da paisagem natural esta invasão poderá comprometer o potencial turístico e principalmente de preservação ambiental ao qual o título de Parque Nacional exige.Palavras chaves: Pinus sp., Landsat, impactos. Dispersion of Exotic Vegetation Into and Around the Lagoa do Peixe National Park ABSTRACTLagoa do Peixe National Park presents a great variety of fragile ecosystems. Among the conflicts present into and around the Park is the increase and dispersion of exotic vegetation, that is generating several discussions. In this context, the objective of this paper was identifying the spatial distribution, over time, of the Pinus sp. plantations in this area. For both researches, it was used multispectral images (Landsat), with dates between 1986 and 2009, and performed the manual classification, field verification and analysis of quantitative and qualitative results. The main problem related to the natural dispersal of Pinus sp. is found on the shore of the park’s main lagoon. This area is bordered by marshes and Pinus sp. whose spontaneous dispersion is competing with the natural vegetation and altering the typical scenery of this region. Since the creation of the park (1986) until today, the area of pinus, around the lagoon, has grown from 61 to 252 ha. This increase, more than four times, makes it necessary its extraction in order to preserve the native species and the biodiversity associated. The expansion of forestry in the Lagoa do Peixe National Park is worrisome because it has been taking a great extent of the area, and there are no actions that indicate a slowdown of this process.Keyword: Pinus sp., Landsat, impact.

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New knowledge about species of the genus Chaerophyllum (Apiaceae) in Latvia

Botanica ◽

10.2478/botlit-2018-0011 ◽

2018 ◽

Vol 24 (2) ◽

pp. 115-123

Author(s):

Pēteris Evarts-Bunders ◽

Gunta Evarte-Bundere

Keyword(s):

Alien Species ◽

Native Species ◽

Human Settlements ◽

Herbarium Material ◽

South Eastern ◽

Root Vegetable ◽

New Knowledge ◽

Critical Revision

Abstract Evarts-Bunders P., Evarte-Bundere G., 2018: New knowledge about species of the genus Chaerophyllum (Apiaceae) in Latvia. - Botanica, 24(2): 115-123. The genus Chaerophyllum belongs to the Apiaceae family, which is one of the most complicated and difficult to identify in Latvia. There are five species verified by herbarium materials known in Latvia: Chaerophyllum aromaticum - native species, rather frequent in all regions in forests, parks and shrublands, C. aureum - anthropophyte, known only from one locality in Daugavpils city along the railway, C. bulbosum - anthropophyte, earlier grown as a root vegetable and now found rarely in parks, at roadsides, waste places, along fences and under canopy of trees close to human settlements, C. hirsutum - native species, known from several localities only in south-eastern part of Latvia, mostly in the Daugava valley - forested ravines, slopes of broad-leaved forests, and C. temulum - alien species, known only from few localities - waste places, railway sides and old manor parks in the whole territory of Latvia. The most striking results are related to the distribution of C. hirsutum in Latvia. The literature sources and herbarium material of Anthriscus nitida, previously known and collected in Latvia, after our critical revision are considered as Chaerophyllum hirsutum, whereas Anthriscus nitida at least in the Latvian flora has not been identified yet and has been removed from the flora lists by mistake.

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