List of invasive species. Migrants from the south
In nature, there are many species of animals that pose a danger to others, feed on them or act as dominants. This is not as scary as it seems at first glance - usually everything in nature is balanced in such a way that all species, despite the death of individual individuals, survive. However, the unimpeded invasion of predators into the habitat where they should not be leads to catastrophic consequences - species and entire ecosystems disappear, and sometimes even human dwellings turn out to be insufficient protection.
1. Starfish Looking like an alien invader, the starfish is a nightmare with skin covered in sharp needles. Usually starfish are 33 cm in diameter and have five rays protruding from the body, which are covered with razor-sharp spines that protect them from most predators. The stars themselves feed on coral polyps.
Starfish have become a problem in their native ecosystem due to environmental changes. Thanks to their insatiable appetite and rapid breeding rate, each star in the "herd" can consume up to six m2 of coral reefs per year, destroying massive patches.
Scientists believe that the too rapid increase in the number of starfish is caused by human-induced changes in the ocean ecosystem, primarily associated with an increased content of nutrient pollution. As a result, programs have been implemented in some areas to destroy starfish using lethal toxins.
2. European starlingStarlings were brought to North America by nostalgic settlers, apparently under the influence of Shakespeare, who in one of his plays described the hero Eugene Scheffelin, a self-proclaimed messiah who called on everyone who left their homeland to lead a bird to a foreign land. 60 starlings were indeed delivered to America in this way, though much later, and released into the wild in Manhattan's Central Park.
Starlings quickly spread across the continent from Central America to Alaska: they invaded cities and fields, destroyed crops, and partially or completely exterminated many native birds, including woodpeckers, tits and swallows.
Flocks of starlings threaten planes - once 62 people died due to the fact that a starling was sucked into the engine of an airliner. Despite large-scale control programs, the number of European starlings in North America is currently about 150 million individuals.
3 Giant Canada GooseAlthough Canada does not have a bird that serves as a symbol of the country, the vast majority of wildlife enthusiasts would attribute this role to the Canada goose, since there are more birds of this species in Canada than any other. However, Canada is a large enough country to have room for several goose subspecies with different habitats and lifestyles.
Canada goose are responsible for the gradual destruction of the coastline along the mouth of the Gulf of Georgia. This area is of great importance as it is a stopover for many species of migratory birds, and it is also the main habitat for salmon, an endangered game fish.
Wildlife researcher Neil C. Doe has conducted field studies on the state of the mouth of the bay and published results showing that geese destroy the natural habitat of many animals and cause disturbances in the food chain.
4. Dark tiger pythonThe majority of invasive species are small animals, however, dark tiger pythons are huge and potentially deadly giants. They first appeared in the Everglades National Park (Florida), the world famous marsh region. This monster, brought to America by conquistadors, is one of the largest snakes on the planet, it grows up to five meters in length and weighs about 90 kg.
Now the number of snakes in the Everglades reaches several thousand individuals, and this is more than in their original habitat in South Asia. Giant pythons, with their powerful jaws and sharp teeth, threaten to destroy the ecosystem of the wetland region as they quickly decimate native species, including the normally invulnerable American alligators.
State conservation authorities consider the extermination of snakes in this region one of the priorities, but to date, all measures taken have been ineffective.
5. Yeah (cane toad)Yep, or the cane toad, is living proof that introducing a second invasive species to control the numbers of one already existing invader can lead to even worse disasters. A huge toxic amphibian (some individuals can weigh about two kg and grow up to 23 cm in length) originally from Central and South America was brought to the islands to reduce the number of beetles devouring sugar cane plantations.
Instead, in order to exterminate the beetles and calm down on this, the Aghas bred over a vast territory, bringing the local fauna into decline. They hunt, among other things, predatory lizards, marsupial mammals and songbirds, and even ruin the egg laying of man-eating sea crocodiles.
As with other invasive species, the number of cane toads remains artificially high in the new environment due to the lack of predators that can feed on them and are resistant to toxins.
The proposal to reduce the population of toads with the help of viruses has raised concerns - in the future, such a measure could cause a chain reaction and cause irreparable damage to the local fauna. By a strange coincidence, the natural toad toxin is currently being used to kill tadpoles.
6. Brown boygaIf a predatory invasive species ends up on an island, then the native species usually lack the ability to cope with a threat that they have never encountered before. Coupled with the lack of predators higher up in the food chain, this could lead to the extinction of native species.
When brown boygies arrived on Guam after World War II, probably as stowaways in the cargo holds of ships, they caused the biggest environmental disaster ever caused by introductions.
Poisonous snakes have destroyed most of the vertebrates native to the forests of the island, they also bite people, and their bites are very painful. In addition, the Boigis have caused frequent power outages as they have invaded human settlements.
In safe conditions, boigas grow up to three meters in length due to an unnaturally large amount of food. To control the number of reptiles, the introduction of toxins into dead mice, which snakes love to eat, is used.
7. Plague rats and miceOn ships, not only people cross the oceans, but also their mortal enemies - rats and mice. Sometimes disease-carrying, rodents become a death sentence for the entire population of seabirds when they land with people on shore: they eat eggs, young and sometimes even adult petrels, puffins and other wetland birds that are not able to protect their nests from land-based predators. .
The presence of invasive rats contributes to the global extinction of seabirds: for example, rats exterminate up to 25,000 petrel chicks per year. No less dangerous are invasive house mice that harm species that are already endangered, for example, Tristan albatrosses: mice not only ruin their clutches, but also eat chicks alive.
8. Domestic catCats are considered man's second best friends, but they also have a reputation as the most dangerous invasive predators, as they intensively destroy the local fauna when they find themselves in a foreign environment. Through direct and indirect human assistance, stray cats have killed millions of continental songbirds, ill-equipped to fend off stealth attacks from a growing number of predators.
The presence of cats on the islands has catastrophic consequences: an unprecedented case is known when the cat of one person caused the complete extinction of one of the bird species in New Zealand - the Stefanov bush wren.
On many islands and continents, invasive cats have reduced bird and small mammal populations. However, there is a downside: some scientists believe that cats can help humans control populations of small predators such as rats.
9 Crab Eating MacaqueMost often, ecologists call humans the main invasive species on the planet, but we rarely imagine monkeys in this role. However, crab-eating macaques are included in the list of the 100 most dangerous invasive species by the International Union for Conservation of Nature. Crab-eating macaques are carnivorous primates that have invaded a number of islands in an unnatural habitat for them thanks to human assistance.
Like many terrestrial predators, crabeater macaques, which also have the rudiments of intelligence, threaten the reproduction of tropical birds and, according to some experts, may be responsible for the rapid extinction of already endangered species.
Macaques can also pose a danger to humans because they carry a deadly strain of the herpes virus that has symptoms similar to herpes simplex, but without proper treatment can lead to brain damage and death.
10. Cow corpseThe invasion of invasive species can prevent people from efficiently using land resources and provide additional conditions for other species, native, to prey on their prey, or, in the case of cow corpses, to parasitize other people's nests.
Initially, cow trupials lived on the plains of North America, where they coexisted with buffaloes and fed on insects climbing around these large herbivorous insects. However, the increase in the number of buffaloes began to prevent the birds from building nests and raising offspring - then the cow corpses began to throw their eggs into the nests of other birds, which is why their own chicks of these species cannot develop normally.
In addition, the reduction of forest areas in some habitats of trupials led to their spread to thousands of km2 of forests, where they caused a decrease in the number of forest songbirds, whose own chicks were doomed to starvation.
However, conservationists sometimes call cow corpses a natural invasive species, since their homeland was the same territories where they live now, no one brought them there. However, cow corpses have managed to reduce even the rare Kirtland treeworts.
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1. Invasion
1.1 List of invasive species
1.2 Invasive species
2. Introduction
2.1 Nature of introduction
2.3 Accidental introduction
2.4 Ecological introduction
1. Invasion (ecology)
Invasion (from Latin invasio - invasion, attack) in ecology and biology - an invasion of a territory or ecosystem of a biological species that is not characteristic of them, which, unlike introduction, occurs without conscious human participation.
Invasion of alien species is currently part of global natural changes and can often cause significant loss of biological diversity and are characterized by the economic importance of ecosystems subject to such biological invasions. Sometimes such invasions can cause significant economic damage and pose a danger to human health.
Examples of invasive species are: Colorado potato beetle, chestnut miner moth, Nile perch, ragweed, Sosnowski's cow parsnip, etc.
To date, there are no universal ways to stop the invasion of aggressive species. The development of measures for the prevention of biological invasions, mitigation of all their consequences and monitoring are the responsibility of the countries that signed the Convention on Biological Diversity in 1992 in Rio de Janeiro.
1.1 List of invasive species
The list of invasive species includes species of animals and plants accidentally introduced by humans into regions new to them, where they successfully take root, begin to multiply and occupy new territories.
Invasive ("aggressive") species have a negative impact on the local fauna and flora, which is why they become pests and quarantine objects. There is some confusion as to whether "invasive" and "introduced" species are fully synonymous. The accidental introduction and damage to native ecosystems distinguishes invasive species from introduced ones.
Animals
Arthropod: Chinese mitten crab. Shellfish: Chinese mitten crab. Insects: Harmonia axyridis, Colorado potato beetle, chestnut miner moth. Ants: Argentine ant, Argentine ant, Red fire ant, Tapinoma melanocephalum, Small fire ant. Mollusks: Crassostrea gigas, Crepidula fornicata, European zebra mussel Ensis directus, Ferrissia fragilis, Potamopyrgus antipodarum, Melanoides tuberculatus, venous rapana. Chordates: Canadian geese in England. Birds: Nile goose, Sukhonos, or Chinese goose, Mountain goose, Canada goose, House crow, Monk parrot, American duck, Cramer's necklace parakeet. Mammals: Gray Rat, American Mink, Coypu Raccoon Dog, Muskrat, Gray Rat, Black Rat
Plants
Edible carpobrotus: Highest ailanthus, Shrub amorpha, Edible carpobrotus, Caulerpa racemosa, Caulerpa taxifolia, Crassula helmsii, Canadian elodea (Elodea canadensis), Fallopia japonica, Gledichia three-prickly, Mantegazzi hogweed, Hydrocotyle ranunculoides, Impatiens glandu-lifera, Myriophyllum aquaticum, Rhododendron ponticum, Robinia pseudoacacia.
Animals
Insects: Tobacco whitefly, Fire ants, German wasp.
mammals
European rabbit, humped camel, domestic dog, domestic goat, African donkey, donkey, domestic horse, cat, house mouse, European rabbit, small rat, gray rat, red fox, koala on about. Kangaroo
In Russia, the agency that controls the import of invasive species is the Federal Service for Veterinary and Phytosanitary Surveillance (Rosselkhoznadzor).
1.2 Invasive species (botany)
Invasive species, or invasive species (English invasive species).
There is no unambiguous and correct definition. In Russian, the term "invasive species" is a morphological transfer from the English phrase invasive species.
In the Western school, a special discipline, defined as invasive plant ecology, deals with the study of invasive species; in Russia, these species are studied by florists as part of the adventitious floras of the regions and separately by specialists in other areas from the point of view of the biology and ecology of such species.
As a rule, a set of species defined as "invasive" is part of a vast alien or adventive element of the flora, among which they stand out, first of all, by the ability to quickly spread and intrude into various types of cenoses.
“Invasive alien species are non-native organisms that cause or may cause damage to the environment, the economy or human health.
Conditions that make it possible to classify specific types of flora of Central Russia as invasive:
*the species is alien (adventive) for most regions of Central Russia;
*the species must be noted in at least 70% of all regions that make up Central Russia;
*in regions where the species is present, it must be at the stage of epe-cophyte or agriophyte at least in part of the territory. It is extremely rare, but it happens that colonophytes, which reproduce in large numbers in places of culture (for example, Sorbaria sorbifolia), should also be classified as invasive species;
*according to the results of long-term observations from the moment of the first discovery, the species shows a tendency to active dispersal;
*the species may be a source of economic damage (but not necessarily).
1.3 List of invasive plants
According to the Black Book of Flora of Central Russia website. Alien plant species in the ecosystems of Central Russia.
Ash-leaved maple, white amaranth, upturned amaranth, Sosnovsky's cow parsnip, common calamus, ragweed wormwood, willow aster, leafy string, fragrant chamomile. Small-flowered canadian, Cyclachena cocklebur, Small-flowered annual, Galinzoga small-flowered, Galinzoga four-beamed, Tuberous sunflower, Jerusalem artichoke, Glutinous ragwort, Canadian golden rod, or Canadian goldenrod, Giant golden rod, or Giant goldenrod, Elbe cocklebur, Iron-bearing impatiens, Impatiens small-flowered Caucasian comfrey, Cardaria vulgaris, French hornwort, Dense-flowered stinkweed, Volga walker, Tatar quinoa, Echinocystis prickly, Goof narrow-leaved, Sea-buckthorn buckthorn, Butterlak euphorbia, Multi-leaved lupine, Canadian elodea, Thin rush, Elsholzia ciliate, or Patrena, Pennsylvanian ash, Fireweed glandular stalk , Fireweed falsely reddening, Evening primrose biennial, or Oslinnik biennial, Oxalis erect, Roofing fire, Rough-leaved fescue, Maned barley, Bluegrass squat, Beskilnitsa spaced, Reinutria Japanese, Reinutria Bohemian, Irga spiky, Irga alder-leaved, Boyar single pistillate yshnik, Fieldfare rowanberry, White poplar
Other notable invasive plants in the area
Robinia false acacia, Gledichia three-thorned, Amorpha shrub, Ailantus highest.
List of the most dangerous invasive species:
introduced species
2. Introduction
Introduction (biological) (from lat. Introductio - “introduction”) - the deliberate or accidental relocation of individuals of any species of animals and plants outside their natural range to new habitats for them. In other words, introduction is the process of introducing alien species into an ecosystem.
An introduced, or alien species (in biology) (from the English Introduced species) is non-indigenous, unusual for a given territory, deliberately or accidentally brought to a new place as a result of human activity.
The process of mastering an introduced species in a new place (adaptation to new environmental conditions) is called acclimatization.
Often, introduced species can significantly change the existing ecosystem of the region and cause a significant reduction or even extinction of certain species of local flora and fauna.
Corn is only in a broad sense an introduced species, since it does not grow wild outside its natural range.
For a number of reasons, the term introduced species is often applied to closely related but different concepts. Similarly, when describing the same case, other terms are used that are similar or close in meaning: they speak of acclimatized, adventitious, alien, exotic, invasive, naturalized, non-native, feral, xenobiotic, etc. species. there is a definite difference between some of these concepts.
Most often, the concept of "introduced" is used as a synonym for the word "alien", and in this sense, according to the above definition, many horticultural and agricultural crops, such as potatoes, corn, etc., widely distributed in the world, can be attributed to introduced plants. However, some sources add to this definition "... and reproduced in the wild", which leaves out the definition of all cultivated crops that are not able to reproduce without human intervention. For such plants, the term "cultivated" or "ornamental" species is used.
There is some confusion as to whether "invasive" and "introduced" species are fully synonymous. Literally invasive are those species of organisms that, being introduced, capture new territories in a new place, harming the existing ecosystem, that is, they become pests. The term implies both actual and potential danger. Some dispute the notion of invasiveness, arguing that the extent of damage is usually beyond calculus, and organisms continue to spread to areas where they never existed, often without regard to whether they may or may not cause harm.
2.1 Nature of introduction
Tiger ambystoma (Ambystoma tigrinum) owes its distribution in California to fisheries, in which it was used as bait. invasion acclimatization introduction
According to the definition, a species is considered introduced if it has been transferred from its natural range to a new territory as a result of human activity. The introduction can be either intentional or accidental. The intentional introduction of new species was motivated by the fact that these species would be useful to a person in a new place and increase his well-being. Thus, in connection with the development of new territories, agricultural crops, livestock and wild animals were imported that could diversify the local fauna. Accidental introduction was a side, often undesirable, product of human activity - for example, the Colorado potato beetle, rats, cockroaches and synanthropic species of fruit flies spread widely. Further distribution of introduced species already in a new territory can occur both with the help of a person and independently.
2.2 Intentional introduction
Organisms deliberately transported by humans can adapt to a new location in two different ways. In the first case, they are specially released into the wild. It is often difficult to predict whether a plant or animal will get along in a new place or not, and sometimes, in the event of a first failure, repeated attempts were made in the hope that new individuals would improve the survival and reproduction of the species. In the second case, the distribution in the wild outside the natural range occurred against the will of man: the animals ran away to freedom and ran wild, and the plants began to grow outside the gardens, household plots and agricultural land.
The most common motivation for conscious introduction was the increase in economic income from local biocenoses. During the period of great geographical discoveries, Europeans transported cultivated plants and livestock with them. For example, carp (Cyprinus carpio) came to the American continent for the purpose of breeding and then spread in the wild. Ampullaria snails (Ampullariidae), as a product rich in protein, were brought to Southeast Asia, and from there they got to the Hawaiian Islands, where they founded a whole branch of the food industry. In 1905, muskrats were transported to Europe from North America for the sake of valuable fur - first they were released into the wild near Prague, and then they settled in the vast territory of Eurasia, even reaching China, Korea and Mongolia. In exactly the same way, arctic foxes appeared on many islands off the coast of Alaska.
Norway maple behaves quite aggressively on the American continent, displacing indigenous plant species.
Sometimes alien species of animals appear due to a passion for sport hunting and fishing - thus, the type of salamander salamander ambystoma (Ambystoma tigrinum) used for bait appeared in California, where it displaces the local endemic species California ambystoma (Ambystoma californiense). Sometimes ordinary domestic animals such as cats, goats, pigs and parrots become wild. Such a new neighborhood does not always benefit the local fauna and flora: for example, feral cats on islands where seabirds unaccustomed to terrestrial predators nest cause a sharp decline in the population and even extinction of local species such as albatrosses and petrels. Settled since the time of pirate goats on the Galapagos Islands, they eat vegetation, due to which local iguanas survive.
Among plants there are also a large number of deliberately introduced species, especially ornamental ones. For example, the European maple (Acer platanoides) in the form of green plantings in gardens and parks came to the American continent, and the ash-leaved maple (Acer negundo), on the contrary, is widely cultivated in Europe, including Russia. Norway maple is known to be an aggressive, invasive species that threatens native species. Ash-leaved maple in Europe is also classified as an aggressive weed species.
The lumber industry has contributed to the spread of the North American radiant pine (Pinus radiata), which is unusual for the southern hemisphere, in Australia.
Cornflower sun (Centaurea solstitialis), which has a long root that allows it to compete with other plants in the extraction of water, threatens the natural ecosystem of Yosemite National Park in the United States.
2.3 Accidental introduction
The Colorado potato beetle gained a foothold in Europe during the First World War and has since begun its victorious march across the continent.
Sometimes organisms travel with a person and independently find themselves in a new environment for them.
For example, three types of rats (black, gray and small) lived in the holds of ships until they moored to a new territory for them. As a result, they are now found even on remote islands, which negatively affects the birds nesting there.
A large number of marine organisms, such as the river zebra mussel (Dreissena polymorpha), accidentally ended up in a new location along with transported water used as ballast.
About 200 alien organisms have settled in the San Francisco Bay, thus making it the most intruded estuary in the world.
In the first half of the 20th century, along with the transported potatoes, it first came to France, and then the Colorado potato beetle established itself throughout Europe, causing considerable harm to agriculture.
Through botanical gardens and collectors of exotic plants, the North American lobed thorn fruit (Echinocystis lobata) entered Europe; with peasant migrants, he ended up in Central Asia; in Siberia, the ways of penetration of this species are associated with the development of tourism, the intensive development of horticulture. It sometimes occupies quite large spaces, both in the vicinity of settlements and quite far from them, and has a high activity in terms of renewal and reproduction.
2.4 Ecological introduction
A special place in the deliberate migration of species is occupied by reintroduction, which consists in the return of species that previously lived in the area, but then disappeared due to human fault. Reintroduction is carried out by interstate and local environmental organizations. One example of such a migration is the reintroduction of the Davidan deer into the Dafeng Milu Reserve near Beijing. This deer was practically exterminated in China in the Middle Ages, and the last individuals remaining in the garden of the emperor died at the end of the 19th century during floods and civil unrest. Miraculously preserved at the courts of Europe, 16 deer marked the beginning of the restoration of the population, part of which was returned to the places where they once lived.
In addition, sometimes, due to a particularly alarming situation that threatens the existence of a species, some animals are relocated to similar climatic conditions in order to preserve it. This happened to the Chinese alligator, which, due to the loss of natural habitats in the Yangtze River valley, was on the verge of extinction. To create a species reserve, several alligators were relocated to the territory of the Rockefeller Wildlife Reserve in the US state of Louisiana.
2.5 Invasive (invasive) species
The Global Invasive Species Program website gives the following definition:
"Invasive alien species are non-native organisms that cause or may cause damage to the environment, economy or human health."
2.6 Invasive exotic diseases
Among the introduced species, there are not only animals and plants, but also various microorganisms - viruses, bacteria and fungi, including pathogens. The most widely known spread of the smallpox virus to the Americas, along with the first conquistadors, in the so-called Columbian exchange, as a result of which entire Indian civilizations were destroyed even before Europeans saw them.
In the XX-XXI century, a serious threat is the spread of such fungi as Endothia parasitica, which causes chestnut endothium cancer, and Ceratocystis ulmi, which causes elm disease.
To implement the phytosanitary principles for plant protection and quarantine, which are consolidated in the International Plant Protection Convention (IPPC) and specified in its International Standards for Phytosanitary Measures, each country has an official national plant protection organization (NPPO).
In Russia, the organization corresponding to the status of the NPPO is the Federal Service for Veterinary and Phytosanitary Surveillance (Rosselkhoznadzor).
List of used literature
1. “Colorado potato beetle, Leptinotarsa decemlineata Say. Phylogeny, morphology, physiology, ecology, adaptation, natural enemies”. M., "Nauka", 2011. 375 p.
2. Elton C. Ecology of invasions of animals and plants = The Ecology of Invasions by Animals and Plants. London, 2012 / Charles Elton / Per. from English. ed. N. P. Naumova. -- M.: Publishing house of foreign literature, 2012.
3. Dgebuadze Yu. Yu. Problems of invasions of alien organisms // Ecological safety and invasions of alien organisms: Collection of round table materials within the framework of the All-Russian Conference on Ecological Security of Russia (June 4-5, 2002). -- M.: MSOP, IPEE RAN, 2002.
4. Vinogradova Yu. K. Code for managing the behavior of invasive alien species in botanical gardens // Botanical gardens in the modern world: theoretical and applied research: Proceedings of the All-Russian Scientific Conference / Demidov A.S .. - M .: Association of Scientific Publications KMK, 2011.
5.Introduction and methods of culture of flower ornamental plants. -- M.: Nauka, 2000. -- 168 p.
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In the modern era, either intentionally or accidentally, a great many species have been introduced into areas where they never existed.
The introduction of many species was due to the following factors.
European colonization . Arriving at new places of settlement in New Zealand, Australia, South Africa, and wanting to make the surroundings more familiar to the eye and provide themselves with traditional entertainment (in particular, hunting), Europeans brought hundreds of European species of birds and mammals there.
Horticulture and agriculture . A large number of species of ornamental plants, agricultural crops and pasture grasses are introduced and grown in new territories. Many of these species "broke free" and settled in local communities.
Overwhelming majority exotic species, that is, species that have found themselves outside their natural range due to human activity, do not take root in new places, with the exception of a certain number of species that are settled there and become invasive species, that is, those that increase in number due to the original species.
Reasons for the invasiveness of exotic species:
1.Competition with natives for a limiting resource.
2. Direct predation.
In the US, invasive exotic species pose a threat to 49% of endangered species; more than 70 species of exotic fish, 80 species of exotic mollusks, 200 species of exotic plants and 2,000 exotic insects now live here.
The swamps of North America are dominated by exotic perennials: loosestrife from Europe and Japanese honeysuckle. Intentionally introduced insects, such as European honey bees(Apis mellifera)and bumblebees(Bombus spp.),and accidentally introduced Richter ants and African honey bees(A. mellifera adansonii or A. mellifera scutelld)created huge populations. These invasive species can have a devastating effect on the local insect fauna, resulting in the decline of many species in the area. In some areas of the southern United States, due to the invasion of exotic Richter ants, the diversity of insect species has decreased by 40%.
Invasive species in aquatic habitats
The influence of invasive species can be especially strong in lakes, rivers and inland seas.
Freshwater bodies of water are like islands in the ocean (just the other way around). Therefore, they are particularly vulnerable to the introduction of exotic species. In water bodies for the sake of commercial or sport fishing, species that are not inherent in them are often introduced. Many species of fish have been unintentionally introduced into inland seas as a result of canal construction and the transport of ballast water by ships. Often, exotic species are larger and more aggressive than the natural fish fauna, and as a result of competition and outright predation, they can gradually drive native fish species to extinction.
In North America, one of the most notable invasions was in the Great Lakes in 1988. . river mussel (Dreissena pofymorpha). This small striped animal from the Caspian Sea was brought from Europe by tankers. In two years, in some parts of Lake Erie, the number of zebra mussel reached 700 thousand individuals per 1 sq. km. km, destroyed many species of molluscs and fish.
The rabbits brought to Australia bred uncontrollably and brought native plants to extinction. Currently, efforts to control rabbits are focused on the importation into Australia of pathogens that selectively affect rabbits.
Mnemiopsis leidyi is one of the representatives of ctenophores, creatures that resemble jellyfish, but belong to a separate type. Initially, these voracious small predators lived only on the coast of North and South America, but in 1982 they were accidentally brought to the Black Sea. Ctenophores began to eat plankton so actively that it led to an ecological disaster.
The Nile perch is a real giant among ray-finned fish, reaching a size of up to two meters and a mass of up to two hundred kilograms. In 1954, these monsters were introduced into Lake Victoria, which led to the extinction of about 200 other fish species.
Humans are the kings of invasiveness. Their number reaches seven billion, thanks to their activities, many species of animals and plants have become extinct, they cause enormous damage to the environment. No one is able to change the world like people do - and this is a reason for both pride and horror.
Cats have been transported by humans all over the planet - this is one of the most successful and dangerous invasive species. Thanks to their hunting skills, many species of birds and small animals disappeared from the islands colonized by Europeans in past centuries. But this did not weaken the love for cats in humanity.
Rhytididae are a family of carnivorous snails known as "cannibal snails". In the middle of the last century, they were brought to the islands of the Indian and Pacific Ocean, without expecting a special catch. However, these gastropods have begun to devour any life forms smaller than themselves, multiplying at a frantic pace - and there is no way to get rid of them.
The Chinese mitten crab was considered a delicacy in its homeland, but it was brought into the waters of Europe and the United States by accident. Since 1912, the crab has spread over a vast territory, damaging the property of fishermen for hundreds of thousands of dollars every year. Crabs dig deep holes, damage nets and dams, spread dangerous diseases.
Yeah, aka the cane toad is the second largest toad in the world, reaching 24 cm in length and weighing over a kilogram. She is very poisonous, and actively uses this for hunting and protection. Introduced to Australia for pest control, toads have become pests themselves, killing many other species with their poison.
Black rat. It is hard to imagine that black rats once lived exclusively in India, as now they can be found all over the world. They live in any kind of home, eat anything, and cause massive damage to wiring and infrastructure.
The brown boiga is a small one with a weak poison, completely harmless to humans. But when these snakes were accidentally brought to the island of Guam, a catastrophe happened - in a few decades, snakes ate almost all local lizards and birds, as well as pollinating insects, which led to the death of many plant species.
Lionfish are beautiful, tasty and poisonous at the same time - a strange combination, but the fact is there. They live and hunt in coral reefs, and thanks to man they have spread far beyond their usual territories. Lionfish pose a serious threat to the fauna of the Caribbean Sea and the Gulf of Mexico.
It is easy to guess that many invasive species have been misplaced by human activities, and Homo sapiens itself is certainly the star of this list. What are the other candidates?