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1.
We investigated characteristics of established non-indigenous (ENI) terrestrial vertebrates in Israel and adjacent areas, as well as attributes of areas they occupy. Eighteen non-indigenous birds have established populations in this region since 1850. A database of their attributes was compiled, analyzed, and compared to works from elsewhere. Most ENI bird species are established locally; a few are spreading or widespread. There has been a recent large increase in establishment. All ENI birds are of tropical origin, mostly from the Ethiopian and Oriental regions; the main families are Sturnidae, Psittacidae, Anatidae, and Columbidae. Most species have been deliberately brought to Israel in captivity and subsequently released or escaped. Most of these birds are commensal with humans to some degree, are not typically migratory, and have mean body mass larger than that of the entire order. ENI birds are not distributed randomly. There are centers in the Tel-Aviv area and along the Rift Valley, which is also a corridor of spread. Positive correlations were found between ENI bird richness and mean annual temperature and urbanization. Mediterranean forests and desert regions have fewer ENI species than expected. Apart from birds we report on non-indigenous species of reptiles (2) and mammals (2) in this region.  相似文献   

2.
Few comprehensive works have investigated non-indigenous snails and slugs as a group. We compiled a database of non-indigenous gastropods in Israel to explore how they arrived and spread, characteristics of their introduction, and their biological traits. Fifty-two species of introduced gastropods are known from Israel (of which nine species subsequently went extinct): 19 species of freshwater snails and 33 species of terrestrial gastropods. The majority of these species are found only in human-dominated habitats. Most of those found in natural habitats are aquatic species. Most snails are introduced unintentionally from various parts of the Holoarctic region, reaching Israel as stowaways with horticultural imports and the aquarium trade, but some are brought intentionally to be used as pets or for food. Because the study of this group in Israel is very limited, information regarding their distribution in the country and their effects on other species is incomplete. Though only nine species of non-indigenous snails have been found to date in natural habitats, some of these are very abundant. More information and research is required to enable effective management schemes.  相似文献   

3.
Natural systems are increasingly being modified by the addition of artificial habitats which may facilitate invasion. Where invaders are able to disperse from artificial habitats, their impact may spread to surrounding natural communities and therefore it is important to investigate potential factors that reduce or enhance invasibility. We surveyed the distribution of non-indigenous and native invertebrates and algae between artificial habitats and natural reefs in a marine subtidal system. We also deployed sandstone plates as experimental 'reefs' and manipulated the orientation, starting assemblage and degree of shading. Invertebrates (non-indigenous and native) appeared to be responding to similar environmental factors (e.g. orientation) and occupied most space on artificial structures and to a lesser extent reef walls. Non-indigenous invertebrates are less successful than native invertebrates on horizontal reefs despite functional similarities. Manipulative experiments revealed that even when non-indigenous invertebrates invade vertical "reefs", they are unlikely to gain a foothold and never exceed covers of native invertebrates (regardless of space availability). Community ecology suggests that invertebrates will dominate reef walls and algae horizontal reefs due to functional differences, however our surveys revealed that native algae dominate both vertical and horizontal reefs in shallow estuarine systems. Few non-indigenous algae were sampled in the study, however where invasive algal species are present in a system, they may present a threat to reef communities. Our findings suggest that non-indigenous species are less successful at occupying space on reef compared to artificial structures, and manipulations of biotic and abiotic conditions (primarily orientation and to a lesser extent biotic resistance) on experimental "reefs" explained a large portion of this variation, however they could not fully explain the magnitude of differences.  相似文献   

4.
Aquatic and semi-aquatic plants comprise few species worldwide, yet the introduction of non-indigenous plants represents one of the most severe examples of biological invasions. My goal is to compare the distribution and the biology of aquatic and semi-aquatic plants in their introduced ranges and in their native ranges. The primary objective of this study is to test the hypothesis that invasive species have evolved traits likely to increase their success in the new range. I made two reciprocal comparisons, i.e. I compared European species in France and in North America, and North American species in France and in North America. Twenty-seven species were classified according to their invasiveness in their introduced area. I␣found six invasive macrophyte species in France native to North America and 17 invasive species in North America native to Europe. Four species are invasive in both areas. There is no general tendency for macrophytes to be more vigorous in their introduced ranges. Most non-indigenous aquatic and semi-aquatic species are potentially invasive or widespread and well-established in their introduced country, while few species seem to be restricted in their distribution.  相似文献   

5.
Non-indigenous species (NIS) are important components of global change, and in order to manage such species it is important to understand which factors affect their success. Interactions with enemies in the new range have been shown to be important for the outcome of introductions, but thus far most studies on NIS–enemy interactions have considered only specialist herbivores in terrestrial systems. Here we present the results from the first biogeographic study that compares herbivore resistance between populations in the native and new region of a non-indigenous seaweed. We show that low consumption of the non-indigenous seaweed by a generalist herbivore is caused by higher chemical defence levels and herbivore resistance in the new range—and not by the failure of the herbivore to recognise the non-indigenous seaweed as a suitable host. Since most seaweed–herbivore interactions are dominated by generalist herbivores, this pattern could be common in marine communities. Our results also reveal that traits used to predict the invasive potential of species, such as their resistance to enemies, can change during the invasion process, but not always in the way predicted by dominant theories.  相似文献   

6.
福建省爬行动物区系及地理区划   总被引:2,自引:0,他引:2  
福建省爬行动物有123种和亚种,隶属2目17科69属.除5种海产龟鳖类及9种海蛇外,其余109种陆栖与半水栖(淡水)的种类中,属东洋界的种类有101种,占92.66%;遍布于古北界和东洋界的种类共有8种,占7.34%.福建省陆栖与半水栖的爬行动物区系可划分为闽北山区丘陵省、闽东丘陵沿海省、闽西低山丘陵省、闽中丘陵平原省和闽南低丘平原省5个地理分布区,对每个地理分布区的自然环境和动物区系的组成和特点分别进行了描述和分析.  相似文献   

7.
This paper provides a review of the first national inventory of non-indigenous species in Austria. In summary, 1110 vascular plant species (27 of the entire flora), 83 mycetes and at least 500 animal species (approximately 1 of the entire fauna) were documented for Austria, which are introduced intentionally or unintentionally by humans after 1492 and reported from the wild. About 25 of non-indigenous vascular plant species have become naturalized. Most non-indigenous vascular plants are native to the Palaearctic region (55%; with 33% originating from the Mediterranean subregion) and North America (20%). More than 90% of non-indigenous plant species are confined to naturally and anthropogenically disturbed (ruderal, urban, arable land, and riverine) habitats. Aquatic ecosystems are more affected and vulnerable to changes in their animal species composition. The current data demonstrate that non-indigenous species continue to invade and disperse and it also emphasize the necessity and responsibility to develop scientific strategies to minimize the impact of biological invasions and to raise public awareness of the problem.  相似文献   

8.

Background

The invasion of habitats by non-indigenous species (NIS) occurs at a global scale and can generate significant ecological, evolutionary, economic and social consequences. Estuarine and coastal ecosystems are particularly vulnerable to pollution from numerous sources due to years of human-induced degradation and shipping. Pollution is considered as a class of disturbance with anthropogenic roots and recent studies have concluded that high frequencies of disturbance may facilitate invasions by increasing the availability of resources.

Methodology/Principal Findings

To examine the effects of heavy metal pollution as disturbance in shaping patterns of exotic versus native diversity in marine fouling communities we exposed fouling communities to different concentrations of copper in one temperate (Virginia) and one tropical (Panama) region. Diversity was categorized as total, native and non-indigenous and we also incorporated taxonomic and functional richness. Our findings indicate that total fouling diversity decreased with increasing copper pollution, whether taxonomic or functional diversity is considered. Both native and non-indigenous richness decreased with increasing copper concentrations at the tropical site whereas at the temperate site, non-indigenous richness was too low to detect any effect.

Conclusions/Significance

Non-indigenous richness decreased with increasing metal concentrations, contradicting previous investigations that evaluate the influence of heavy metal pollution on diversity and invasibility of fouling assemblages. These results provide first insights on how the invasive species pool in a certain region may play a key role in the disturbance vs. non-indigenous diversity relationship.  相似文献   

9.

Aim

Trait-based approaches are powerful to examine the processes associated with biological invasions. Functional comparison among native and non-indigenous species (NIS) can notably infer whether novel assemblages result from neutral or niche-based assembly rules. Applying such a framework to biofouling communities, our study aimed to elucidate their distributions within two marine urban habitats (namely floating vs. nonfloating habitats).

Location

Southeast Pacific—Central Chilean coastline.

Methods

Here, we examined the distribution of 12 functional traits in fouling communities established on settlement plates, after 3 and 13 months of deployment in the two habitats and across ports in Central Chile. Based upon previously described differences of assemblages and NIS contribution across habitats, we hypothesized that nonindigenous, cryptogenic and native taxon pools would be functionally distinct (and trait biased), and that functional diversity and structure would vary across habitats and successional stages.

Results

Our results show, as anticipated, that nonindigenous (13 taxa), cryptogenic (12) and native (18) taxon pools are functionally distinct, though overlapping in the trait space. Non-indigenous species are rather related to colonizing traits, while native species are more related to competitive traits. Only one widespread NIS was functionally similar to the late successional and most competitive native species, including taxa elsewhere invasives. Despite differences in taxonomic composition between habitats, we did not observe functional differences between them. In contrast, temporal variations across colonization stages were detected along with an increased contribution in large and long-lived taxa, together with site-specific trajectories.

Main Conclusions

We conclude that the functional distinctness among nonindigenous, cryptogenic and native taxa occupying artificial habitats in ports reflects niche-based processes. Site-specific trajectories indicate that scale-dependent assembly processes, such as dispersal and species interactions, are at play.  相似文献   

10.
Although recent research has shown that non-indigenous species often increase local-scale species richness, few have documented how such increases translate into compositional changes across biological scales. In particular, transformations of biodiversity patterns may be acute within regions that are simultaneously extinction and invasion hotspots (i.e. double-hotspots), such as the Hawaiian Islands. Nevertheless, modification of diversity relationships in such places are rarely quantified. Here, I utilize passerine non-indigenous species introductions and native species extinctions on Hawaii to quantitatively explore the changing relationship between within- (alpha), between- (beta), and across-island (gamma) diversity. My results indicate that, even after incorporating the enrichment effects of non-indigenous species invasions, across-island passerine diversity has dropped substantially. Nevertheless, within-island diversity has remained largely unchanged, or in some cases increased. Perhaps the more profound changes in diversity have come from the loss of between-island diversity. Because nearly all native Hawaiian passerines are extinct or near extinction, the current diversity relationships are inordinately influenced by patterns in the transportation and establishment of non-indigenous birds. These human-induced ‘dispersal’ patterns are markedly different from natural ones. In addition, these dispersal patterns may be unique to vagile species such as birds, thus indicating that transformations of diversity within other groups (e.g. plants or freshwater fishes) currently inhabiting Hawaii may differ. These results suggest the need to explore how alteration of diversity relationships translate into the loss of ecosystem services, or other valued components of biodiversity.  相似文献   

11.
Non-indigenous species may be the most severe environmental threat the world now faces. Fishes, in particular, have been intentionally introduced worldwide and have commonly caused the local extinction of native fish. Despite their importance, the impact of introduced fishes on threatened populations of Pacific salmon has never been systemically examined. Here, we take advantage of several unique datasets from the Columbia River Basin to address the impact of non-indigenous brook trout, Salvelinus fontinalis, on threatened spring/summer-run chinook salmon, Oncorhynchus tshawytscha. More than 41 000 juvenile chinook were individually marked, and their survival in streams without brook trout was nearly double the survival in streams with brook trout. Furthermore, when brook trout were absent, habitat quality was positively associated with chinook survival, but when brook trout were present no relationship between chinook survival and habitat quality was evident. The difference in juvenile chinook survival between sites with, and without, brook trout would increase population growth rate (lambda) by ca. 2.5%. This increase in lambda would be sufficient to reverse the negative population growth observed in many chinook populations. Because many of the populations we investigated occur in wilderness areas, their habitat has been considered pristine; however, our results emphasize that non-indigenous species are present and may have a dramatic impact, even in remote regions that otherwise appear pristine.  相似文献   

12.
Haminoea japonica is an opisthobranch mollusk with a large non-indigenous range. This species is a vector for a parasite that causes the human skin disease cercarial dermatitis, and may have negative effects on populations of native species. Molecular evidence from the mitochondrial cytochrome c oxidase I gene and the histone 3 nuclear gene indicates that previously published morphology-based hypotheses on the spread of H. japonica out of Japan are correct. The most likely explanation for the current range of the species, which includes Japan, Korea, France, Spain, Italy, Canada and the USA is a recent, human-mediated dispersal from Japanese populations. The highest levels of nucleotide and haplotype diversity are found in Japan. Non-indigenous populations have low levels of genetic diversity (indicating bottlenecking). Haplotypes that were detected in the non-indigenous range of H. japonica have only been found in two localities in the native range; these two localities are in north-eastern Japan. In addition, the haplotype network structure and Spatial Analysis of Molecular Variance results confirm the origins of non-indigenous populations most likely trace to north-eastern Japan, which is where most Pacific oyster exports to North America also originated. Because there are no major shipping ports in north-eastern Japan, ballast water is less likely to be the mechanism of dispersal. The results of this study provide important data for the development of policies and regulations aimed to prevent further spread of this species in non-indigenous ranges.  相似文献   

13.
The degree to which biotic interactions influence invasion by non-indigenous species may be partly explained by the evolutionary relationship of these invaders with natives. Darwin’s naturalization hypothesis controversially proposes that non-native plants are more likely to invade if they lack close relatives in their new range. A possible mechanism for this pattern is that exotics that are more closely related to natives are more likely to share their herbivores, and thus will suffer more damage than phylogenetically isolated species. We tested this prediction using exotic plants in Ontario, Canada. We measured herbivore damage to 32 species of exotic plants in a common garden experiment, and 52 in natural populations. We estimated their phylogenetic distances from locally occurring natives in three ways: as mean distance (age) to all native plants, mean distance to native members of the same family, and distance to the closest native species. In the common garden, the proportion of leaves damaged and the average proportion of leaf area damaged declined with mean phylogenetic distance to native family relatives by late summer. Distance to native confamilials was a better predictor of damage than distance to the closest native species, while mean distance to the entire native plant community failed to predict damage. No significant patterns were detected for plants in natural populations, likely because uncontrolled site-to-site variation concealed these phylogenetic trends. To the extent that herbivory has negative demographic impacts, these results suggest that exotics that are more phylogenetically isolated from native confamilials should be more invasive; conversely, native communities should be more resistant to invasion if they harbor close familial relatives of potential invaders. However, the large scatter in this relationship suggests that these often are likely to be weak effects; as a result, these effects often may be difficult to detect in uncontrolled surveys of natural populations.  相似文献   

14.
Ecology of forest insect invasions   总被引:1,自引:0,他引:1  
Forests in virtually all regions of the world are being affected by invasions of non-native insects. We conducted an in-depth review of the traits of successful invasive forest insects and the ecological processes involved in insect invasions across the universal invasion phases (transport and arrival, establishment, spread and impacts). Most forest insect invasions are accidental consequences of international trade. The dominant invasion ‘pathways’ are live plant imports, shipment of solid wood packaging material, “hitchhiking” on inanimate objects, and intentional introductions of biological control agents. Invading insects exhibit a variety of life histories and include herbivores, detritivores, predators and parasitoids. Herbivores are considered the most damaging and include wood-borers, sap-feeders, foliage-feeders and seed eaters. Most non-native herbivorous forest insects apparently cause little noticeable damage but some species have profoundly altered the composition and ecological functioning of forests. In some cases, non-native herbivorous insects have virtually eliminated their hosts, resulting in major changes in forest composition and ecosystem processes. Invasive predators (e.g., wasps and ants) can have major effects on forest communities. Some parasitoids have caused the decline of native hosts. Key ecological factors during the successive invasion phases are illustrated. Escape from natural enemies explains some of the extreme impacts of forest herbivores but in other cases, severe impacts result from a lack of host defenses due to a lack of evolutionary exposure. Many aspects of forest insect invasions remain poorly understood including indirect impacts via apparent competition and facilitation of other invaders, which are often cryptic and not well studied.  相似文献   

15.
Many European politicians, managers, and scientists believe that non-indigenous species cannot be eradicated and that attempts to do so are hazardous because of frequent undesirable results. This notion seems to be based on the view that successful eradications undertaken in many other parts of the world cannot be generalised. To allow reasoned consideration of this argument, the eradication of non-indigenous vertebrate species performed in the French territories (European and overseas) and their recorded consequences on native fauna and flora are synthesised. Nineteen vertebrate eradication attempts were recorded, with seven mammal species as the targets. Of these attempts four failed for technical reasons and one for reasons undetermined as yet. These operations took place on islands of four biogeographical areas (West-European, Mediterranean, West Indies and Indian Ocean subantarctic) except a continental one (West-European continent). Among these 19 attempts, 13 were conducted according to a global strategy that provided data on the impact of the disappearance of the non-indigenous species on several native species. This impact, never detrimental, was determined for 14 species (one mammal, nine birds, one marine turtle, one crab, one beetle, one plant). Unexpected consequences of the disappearance of the invader were recorded for four native species (29%). This result highlights the poverty of natural historical information for several taxa and the flimsiness of the empty niche concept that is often used to argue for the delay of or to prevent any action again a non-indigenous species. If French territories can be taken as an example, eradications of non-indigenous species are not impossible; a good risk assessment prevents undesirable long-term consequences for native species and several native species benefited from the disappearance of the invader. Furthermore, eradication constitutes a powerful experimental tool for ecology and natural history studies if conceived as both a management and research operation. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

16.
Fourteen non-indigenous fish species have been successfully introduced to the wild within the territory of Flanders; nine are considered naturalized. Most of the introductions occurred prior to 1950, with six species introduced since then. This paper reviews the available, hitherto scattered, information (including 'grey literature') on these 14 non-indigenous fish species introductions, and evaluates a decade of data from fisheries surveys to assess the recent development of these non-indigenous populations. Gibel carp Carassius gibelio and topmouth gudgeon Pseudorasbora parva are the most widespread of the non-indigenous species in Flemish waters, and both continue to expand their ranges. A reduction in range has been observed in brown bullhead Ameiurus nebulosus only. A case is presented for not including European catfish Silurus glanis , sunbleak Leucaspius delineatus and European bullhead Cottus gobio on the list of non-indigenous freshwater fishes in Flanders. Also discussed are non-indigenous fish species that are likely to colonize Flanders inland waters in the near future.  相似文献   

17.
Coastal Fynbos on the Agulhas Plain of the Western Cape, South Africa, has been transformed extensively by crop and pastoral agriculture. Many bird species, e.g. sunbirds, nightjars and mousebirds have consequently been affected negatively by the reduction of suitable habitat for daily requirements. However, populations of certain bird species, especially granivores and omnivores, such as sparrows, larks and pipits, as well as Egyptian Geese and Helmeted Guineafowl have proliferated on the Agulhas Plain. This study investigates the effects of agricultural development on overall bird diversity on the Agulhas Plain. In 1998, twice monthly transect counts at 13 farmland sites recorded 106 bird species. Fifteen species occurred at 75% or more of the sites. Highest avian diversity was recorded at the sites with a mixture of crops and Coastal Fynbos (Mixed regime). A small number of species, e.g. sunbirds, are reliant on the natural Coastal Fynbos for their survival. With the exception of the Mixed regime that gained 50 species, all the other agricultural regimes reflected a loss of diversity when compared with Fynbos. To provide more suitable habitat for a greater diversity of birds, mixed landscapes should be maintained, and further destruction of natural Fynbos habitat should be prevented.  相似文献   

18.
M. Kehat  S. Greenberg 《BioControl》1970,15(3):275-280
The importance ofCoccinellidae species found in the citrus groves of Israel was evaluated according to their prey, frequency and distribution. Dense populations of aphidophagous coccinellids were found very often, feeding on scale insects in citrus groves where none of their usual prey was present; these may therefore also be important as scale predators. A few species were distributed equally in all areas, some were more frequent in the Coastal Plain and others in the warmer parts of the country.  相似文献   

19.
Despite the widespread perception that non-native species threaten biodiversity, there are few documented cases of non-native species displacing rare or specialized native species. Here, I examined changes in plant species composition over 5 years during patch expansion of a non-native grass, Imperata cylindrica, in longleaf pine flatwoods in Mississippi, USA. I used a multivariate approach to quantify the degree of habitat specialization and geographic range of all species encountered. I examined losses of species collectively as a function of plant height (controlling for initial frequency) and then the relationship between height and the degree of association with longleaf pine flatwoods, disturbed habitats, and the outer Gulf Coastal Plain of the southeastern USA. Patch expansion resulted in dramatic declines in species richness and increases in ground-level shade at both sites in just 3 years. Most tall saplings, shrubs, and vines were not endemic to longleaf pine communities and were less likely to be displaced than short herbs, most of which were indicative of longleaf pine communities. These results suggest that invasion of longleaf pine communities by I. cylindrica will likely cause significant losses of short, habitat-specialists and reduce the distinctiveness of the native flora of these threatened ecosystems.  相似文献   

20.
Insects are among the world’s most ecologically and economically important invasive species. Here we assemble inventories of native and non-native species from 20 world regions and contrast relative numbers among these species assemblages. Multivariate ordination indicates that the distribution of species among insect orders is completely different between native and non-native assemblages. Some orders, such as the Psocoptera, Dictyoptera, Siphonaptera, Thysanoptera, and Hemiptera, are always over-represented in the non-native compared to native assemblages. Other orders, such as the Plecoptera, Trichoptera, Ephemeroptera, Odonata, Mecoptera and Microcoryphila, are consistently under-represented in non-native assemblages. These patterns most likely arise both as a result of variation among taxa in their association with invasion pathways responsible for transporting species among world regions, as well as variation in life-history traits that affect establishment potential. However, our results indicate that species compositions associated with invasiveness are fundamentally different from compositions related to insularity, indicating that colonization of islands selects for a different group of insect taxa than does selection for successful invaders. Native and non-native assemblage compositions were also related, to a lesser extent, to latitude of the region sampled. Together, these results illustrate the dominant role of invasion pathways in shaping the composition of non-native insect assemblages. They also emphasize the difference between natural background colonization of islands and anthropogenic colonization events, and imply that biological invasions are not a simple subset of a long-standing ecological process.  相似文献   

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