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113-551: The Guiana Shield underlies Guyana (previously British Guiana ), Suriname (previously Dutch Guiana ), and French Guiana (or Guyane ), much of southern Venezuela , as well as parts of Colombia and Brazil . The rocks of the Guiana Shield consist of metasediments and metavolcanics ( greenstones ) overlain by sub-horizontal layers of sandstones , quartzites , shales and conglomerates intruded by sills of younger mafic intrusives such as gabbros . The oldest rocks in

226-640: A National Protected Area System. More than 80% of Guyana is still covered by forests, which also contain the world's rarest orchids , ranging from dry evergreen and seasonal forests to montane and lowland evergreen rain forests. These forests are home to more than a thousand species of trees. Guyana's tropical climate, unique geology, and relatively undisturbed ecosystems support extensive areas of species-rich rain forests and natural habitats with high levels of endemism . There are about 8000 species of plants in Guyana, half of which are found nowhere else. The country

339-712: A Ramsar Wetland, thus becoming a protected area of international importance in accordance to the Ramsar Convention . According to recent researches, although ecosystems of the Guayana Highlands remain vibrant, emerging issues (including "a well-known invasive plant elsewhere" Poa annua and "one of the most aggressive weeds" Polypogon elongatus ) and infectious faecal bacteria Helicobacter pylori have been documented. Guyana in South America  (grey) Guyana officially

452-733: A ballast tank of a ship traveling from the temperate zone through tropical waters may experience temperature fluctuations as much as 20 °C. Heat challenges during transport may enhance the stress tolerance of species in their non-native range, by selecting for genotypes that will survive a second applied heat stress, such as increased ocean temperature in the founder population. Invasive species often exploit disturbances to an ecosystem ( wildfires , roads , foot trails ) to colonize an area. Large wildfires can sterilize soils, while adding nutrients . Invasive plants that can regenerate from their roots then have an advantage over natives that rely on seeds for propagation. Invasive species can affect

565-595: A few of the traits, and that noninvasive species had these also. Common invasive species traits include fast growth and rapid reproduction , such as vegetative reproduction in plants; association with humans; and prior successful invasions. Domestic cats are effective predators; they have become feral and invasive in places such as the Florida Keys . An introduced species might become invasive if it can outcompete native species for resources. If these species evolved under great competition or predation , then

678-680: A great decrease in the population size and may constrict genetic variation , the individuals begin to show additive variance as opposed to epistatic variance. This conversion can lead to increased variance in the founding populations, which permits rapid evolution . Selection may then act on the capacity to disperse as well as on physiological tolerance to new stressors in the environment, such as changed temperature and different predators and prey. Rapid adaptive evolution through intraspecific phenotypic plasticity, pre-adaptation and post-introduction evolution lead to offspring that have higher fitness. Critically, plasticity permits changes to better suit

791-470: A habitat in ways advantageous to other species. For example, zebra mussels increase habitat complexity on lake floors, providing crevices in which invertebrates live. This increase in complexity, together with the nutrition provided by the waste products of mussel filter-feeding , increases the density and diversity of benthic invertebrate communities. Introduced species may spread rapidly and unpredictably. When bottlenecks and founder effects cause

904-434: A key component for receiving international aid through REDD programmes. The earliest residents of Guyana employed a variety of agricultural practices for subsistence living but also had extensive networks of trade, dealing in items such as blow pipes, curare , cassava graters, and other essentials. These trade networks were important even at the time of the earliest European contact, and Dutch traders were inclined to gift

1017-476: A large impact on Guyana's GDP since drilling began in 2019. GDP grew sharply (43%) through the COVID-19 pandemic year of 2020, and is anticipated to continue at a high level in 2021 (estimated at 20%). The non-oil sectors contracted as public health measures were in place to control the virus spread; the growth of GDP rests on the oil sector for these two years. Preservation of Guyana's pristine forests has been

1130-543: A long taproot , or to live on previously uninhabited soil types. For example, barbed goatgrass was introduced to California on serpentine soils , which have low water-retention, low nutrient levels, a high magnesium / calcium ratio, and possible heavy metal toxicity. Plant populations on these soils tend to show low density, but goatgrass can form dense stands on these soils and crowd out native species. Invasive species might alter their environment by releasing chemical compounds, modifying abiotic factors, or affecting

1243-403: A major role in exotic species introduction. High demand for the valuable Chinese mitten crab is one explanation for the possible intentional release of the species in foreign waters. Maritime trade has rapidly affected the way marine organisms are transported within the ocean; new means of species transport include hull fouling and ballast water transport. In fact, Molnar et al. 2008 documented

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1356-551: A more realistic exchange rate, fairly low inflation, and the continued support of international organisations. Guyana held huge amounts of debt which have been written off through various international agencies. In 2003 Guyana qualified for US$ 329 million of debt relief, in addition to the US$ 256 million from the original World Bank plan for assisting heavily indebted poor countries in 1999. The Multilateral Debt Relief Initiative in 2006/7 wrote off about US$ 611 million of Guyana's debt by

1469-674: A new nomenclature system based on biogeography rather than on taxa . By discarding taxonomy, human health , and economic factors, this model focused only on ecological factors. The model evaluated individual populations rather than entire species. It classified each population based on its success in that environment. This model applied equally to indigenous and to introduced species, and did not automatically categorize successful introductions as harmful. The USDA's National Invasive Species Information Center defines invasive species very narrowly. According to Executive Order 13112, " 'Invasive species' means an alien species whose introduction does or

1582-407: A number of years and then experience an explosion in population, a phenomenon known as "the lag effect". Hybrids resulting from invasive species interbreeding with native species can incorporate their genotypes into the gene pool over time through introgression . Similarly, in some instances a small invading population can threaten much larger native populations. For example, Spartina alterniflora

1695-554: A particular pest species could pollute soil and surface water. Encroachment of humans into previously remote ecosystems has exposed exotic diseases such as HIV to the wider population. Introduced birds (e.g. pigeons ), rodents and insects (e.g. mosquito , flea , louse and tsetse fly pests) can serve as vectors and reservoirs of human afflictions. Throughout recorded history, epidemics of human diseases, such as malaria , yellow fever , typhus , and bubonic plague , spread via these vectors. A recent example of an introduced disease

1808-418: A result of either a numerical or fitness advantage of the introduced species. Genetic pollution occurs either through introduction or through habitat modification, where previously isolated species are brought into contact with the new genotypes. Invading species have been shown to adapt to their new environments in a remarkably short amount of time. The population size of invading species may remain small for

1921-853: A wide variety of natural habitats and very high biodiversity . The country also hosts a part of the Amazon rainforest , the largest tropical rainforest in the world. The region known as " the Guianas " consists of the large shield landmass north of the Amazon River and east of the Orinoco River known as the "land of many waters". Nine indigenous tribes reside in Guyana: the Wai Wai , Macushi , Patamona , Lokono , Kalina , Wapishana , Pemon , Akawaio and Warao . Historically dominated by

2034-596: Is tropical and generally hot and humid, though moderated by northeast trade winds along the coast. There are two rainy seasons, the first from May to mid-August, the second from mid-November to mid-January. Guyana has one of the largest unspoiled rainforests in South America, some parts of which are almost inaccessible by humans. The rich natural history of Guyana was described by early explorers Sir Walter Raleigh and Charles Waterton and later by naturalists Sir David Attenborough and Gerald Durrell . In 2008,

2147-629: Is a natural phenomenon, but human-facilitated introductions have greatly increased the rate, scale, and geographic range of invasion. For millennia, humans have served as both accidental and deliberate dispersal agents, beginning with their earliest migrations , accelerating in the Age of Discovery , and accelerating again with international trade . Notably invasive plant species include the kudzu vine, giant hogweed , Japanese knotweed , and yellow starthistle . Notably invasive animals include European rabbits , domestic cats , and carp . Invasive species are

2260-488: Is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions , causing ecological, environmental, and/or economic damage. The term can also be used for native species that become harmful to their native environment after human alterations to its food web . Since the 20th century, invasive species have become serious economic, social, and environmental threats worldwide. Invasion of long-established ecosystems by organisms

2373-491: Is equally rich and 13,367 species of vascular plants have been found, approximately 40% of which is considered endemic. The shield is overlain by the largest expanse of tropical forest on any Precambrian shield area in the world. Guianan rain forest is similar in nature to Amazonian rain forest and known protected areas include the Iwokrama Forest of central Guyana, Kaieteur, Kanuku National Park of southern Guyana,

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2486-456: Is highly fire-adapted. It spreads rapidly after burning, and increases the frequency and intensity of fires by providing large amounts of dry detritus during the fire season in western North America. Where it is widespread, it has altered the local fire regimen so much that native plants cannot survive the frequent fires, allowing it to become dominant in its introduced range. Ecological facilitation occurs where one species physically modifies

2599-482: Is home to six ecoregions: Guayanan Highlands moist forests , Guianan moist forests , Orinoco Delta swamp forests , Tepuis , Guianan savanna , and Guianan mangroves . The Guiana Shield region is little known and extremely rich biologically. Unlike other areas of South America, over 70% of the natural habitat remains pristine. Guyana ranks third in the world with a 2019 Forest Landscape Integrity Index mean score of 9.58/10. The rich natural history of British Guiana

2712-623: Is likely to cause economic or environmental harm or harm to human health." Typically, an introduced species must survive at low population densities before it becomes invasive in a new location. At low population densities, it can be difficult for the introduced species to reproduce and maintain itself in a new location, so a species might reach a location multiple times before it becomes established. Repeated patterns of human movement, such as ships sailing to and from ports or cars driving up and down highways, offer repeated opportunities for establishment (a high propagule pressure ). In ecosystems ,

2825-600: Is normal, and preserves constellations of genes and genotypes. An example of this is the interbreeding of migrating coyotes with the red wolf , in areas of eastern North Carolina where the red wolf was reintroduced, reducing red wolf numbers. In South Africa's Cape Town region, analysis demonstrated that the restoration of priority source water sub-catchments through the removal of thirsty alien plant invasions (such as Australian acacias, pines and eucalyptus, and Australian black wattle) would generate expected annual water gains of 50 billion liters within 5 years compared to

2938-552: Is now Guyana has been inhabited for millennia. Nine indigenous tribes reside in Guyana: the Wai Wai , Macushi , Patamona , Lokono , Kalina , Wapishana , Pemon , Akawaio , and Warao . Many of these peoples practised shifting agriculture alongside hunting . Historians speculate that the Arawaks and Caribs originated in the South American hinterland and migrated northward, first to the present-day Guianas and then to

3051-581: Is now considered invasive in over 60 countries, and has invaded large geographies in several countries prompting aggressive federal efforts at attempting to control it. Primary geomorphological effects of invasive plants are bioconstruction and bioprotection. For example, kudzu ( Pueraria montana ), a vine native to Asia, was widely introduced in the southeastern United States in the early 20th century to control soil erosion . The primary geomorphological effects of invasive animals are bioturbation , bioerosion , and bioconstruction. For example, invasions of

3164-479: Is one of the most problematic invasive plant species in eastern North American forests, where it is highly invasive of the understory , reducing the growth rate of tree seedlings and threatening to modify the forest's tree composition. Native species can be threatened with extinction through the process of genetic pollution . Genetic pollution is unintentional hybridization and introgression , which leads to homogenization or replacement of local genotypes as

3277-698: Is the highest summit of the larger Neblina massif , a highly eroded sandstone plateau that straddles the Venezuela-Brazil border and that has lost the typical tabletop shape of the other tepuis in the region. The Guiana Shield is one of the regions of highest biodiversity in the world, and has many endemic species. The region houses over 3000 vertebrate species: 1168 fresh water fish, 269 amphibians (54% endemics), 295 reptiles (29%), 1004 birds (7.7%), and 282 mammals (11%). Diversity of invertebrates remains largely undocumented, but there are several species of endemic butterflies and dung beetles. Plant life

3390-514: Is the main cause of introductions – other than for polar regions . Diseases may be vectored by invasive insects: the Asian citrus psyllid carries the bacterial disease citrus greening . The arrival of invasive propagules to a new site is a function of the site's invasibility. Many invasive species, once they are dominant in the area, become essential to the ecosystem of that area, and their removal could be harmful. Economics plays

3503-490: Is the only mainland South American nation in which English is the official language. However, the majority of the population speak Guyanese Creole , an English-based creole language , as a first language. Guyana is part of the Commonwealth Caribbean . It is part of the mainland Caribbean region maintaining strong cultural, historical, and political ties with other Caribbean countries as well as serving as

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3616-592: Is the spread of the West Nile virus , which killed humans, birds, mammals, and reptiles. The introduced Chinese mitten crabs are carriers of Asian lung fluke . Waterborne disease agents, such as cholera bacteria ( Vibrio cholerae ), and causative agents of harmful algal blooms are often transported via ballast water. Globally, invasive species management and control are substantial economic burdens, with expenditures reaching approximately $ 1.4 trillion annually. The economic impact of invasive alien species alone

3729-462: Is the third-smallest sovereign state by area in mainland South America after Uruguay and Suriname, and is the second-least populous sovereign state in South America after Suriname; it is also one of the least densely populated countries on Earth . The official language of the country is English , although a large part of the population is bilingual in English and the indigenous languages. It has

3842-567: The Akawaio , Arawak ( Lokono ), Arekuna ( Pemon ), Carib ( Karinya ), Makushi , Patamona , Wai Wai , Wapichan , and Warao . They are the third-largest demographic group in the country and are the majority population in the southern interior. The Afro-Guyanese population mainly descend from West African ethnicities such as the Ashanti from Ghana , the Yoruba from Southwest Nigeria ,

3955-571: The BBC broadcast a three-part programme called Lost Land of the Jaguar which highlighted the huge diversity of wildlife, including undiscovered species and rare species such as the giant otter and harpy eagle . Guyana has one of the highest levels of biodiversity in the world. It is home to more than 225 species of mammals , 900 species of birds , 880 species of reptiles, and more than 6,500 different species of plants. Among these wildlife categories

4068-578: The Co-operative Republic of Guyana , is a country on the northern coast of South America , part of the historic mainland British West Indies . Georgetown is the capital of Guyana and is also the country's largest city. Guyana is bordered by the Atlantic Ocean to the north, Brazil to the south and southwest, Venezuela to the west, and Suriname to the east. With a land area of 214,969 km (83,000 sq mi), Guyana

4181-684: The Courentyne River at 724 km (450 mi), the Berbice at 595 km (370 mi), and the Demerara at 346 km (215 mi). The Courentyne river forms the border with Suriname. At the mouth of the Essequibo are several large islands, including the 145 km (90 mi) wide Shell Beach along the northwest coast, which is also a major breeding area for sea turtles (mainly leatherbacks ) and other wildlife. The climate

4294-522: The Great Lakes via ballast water. These outcompete native organisms for oxygen and food, and can be transported in the small puddle left in a supposedly empty ballast tank. Regulations attempt to mitigate such risks, not always successfully. Climate change is causing an increase in ocean temperature . This in turn will cause range shifts in organisms, which could harm the environment as new species interactions occur. For example, organisms in

4407-621: The Igbo from South-Eastern Nigeria , and the Mandingo from Senegal . Most Indo-Guyanese are descended from indentured labourers who migrated from North India , especially the Bhojpur and Awadh regions of the Hindi Belt in the present-day states of Uttar Pradesh , Bihar , and Jharkhand . A significant minority of Indo-Guyanese are also descended from indentured migrants who came from

4520-674: The International Monetary Fund , the World Bank and the Inter-American Development Bank . In 2006, Japan finalised its bilateral debt cancellation agreement, in 2007, US$ 15 million was written off by China and in 2008, Venezuela cancelled US$ 12.5 million. In 2008, the economy witnessed a 3% increase in growth amid the global economic crisis ; it grew 5.4% in 2011 and 3.7% in 2012. IMF projected economic growth to be 53% in 2020 following

4633-462: The Macushi people). When the country gained independence from British rule, a policy of nationalisation was enacted by Forbes Burnham to address the inequities that were established by plantation-based colonial rule. All large-scale industries such as foreign-owned bauxite mining ( Reynolds Metals and Rio Tinto's Alcan) and sugar ( GuySuCo ) operations were taken over by the government. However,

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4746-613: The Orinoco and Courantyne rivers. Dutch sovereignty over these settlements was recognised in 1648 by Spain with the Peace of Münster , which stated under Article 5 that the Dutch would retain all of the lordships, cities, castles, fortresses, trades and lands in the... West Indies under their possession at the time. However, the treaty did not specify the boundary between Spanish Guiana and Dutch Guiana . Guyana achieved independence from

4859-596: The People's National Congress Reform rose to power, quickly becoming a repressive authoritarian leader. Politics became divided on race with the Afro-Guyanese supporting Burnham's People's National Congress and the Indo-Guyanese supporting Jagan 's People's Progressive Party , in what became known as aapan jaat politics, loosely translated from Guyanese Hindustani as "vote for your own kind". Guyana

4972-599: The economic returns from invasive species are far less than the costs they impose. In the Great Lakes region the sea lamprey is an invasive species. In its original habitat, it had co-evolved as a parasite that did not kill its host. However, in the Great Lakes Region, it acts as a predator and can consume up to 40 pounds of fish in its 12–18 month feeding period. Sea lampreys prey on all types of large fish such as lake trout and salmon . The sea lampreys' destructive effects on large fish negatively affect

5085-844: The extinction of species, loss in biodiversity, and loss of ecosystem services , costs from impacts of invasive species would drastically increase. It is often argued that the key to invasive species management is early detection and rapid response. However, early response only helps when the invasive species is not frequently reintroduced into the managed area, and the cost of response is affordable. Weeds reduce yield in agriculture . Many weeds are accidental introductions that accompany imports of commercial seeds and plants. Introduced weeds in pastures compete with native forage plants, threaten young cattle (e.g., leafy spurge, Euphorbia virgata ) or are unpalatable because of thorns and spines (e.g., yellow starthistle ). Forage loss from invasive weeds on pastures amounts to nearly US$ 1 billion in

5198-556: The headquarters for the Caribbean Community (CARICOM). In 2008, the country joined the Union of South American Nations as a founding member. In 2017, 41% of the population of Guyana lived below the poverty line . Guyana's economy has been undergoing a transformation since the discovery of crude oil in 2015 and commercial drilling in 2019, with its economy growing by 49% in 2020, making it, by some accounts, currently

5311-744: The spatial scale of invasion studies. Small-scale studies tended to show a negative relationship between diversity and invasion, while large-scale studies tended to show the reverse, perhaps a side-effect of invasives' ability to capitalize on increased resource availability and weaker species interactions that are more common when larger samples are considered. However, this pattern does not seem to hold true for invasive vertebrates. Island ecosystems may be more prone to invasion because their species face few strong competitors and predators, and because their distance from colonizing species populations makes them more likely to have "open" niches. For example, native bird populations on Guam have been decimated by

5424-477: The 958 endangered species under the Endangered Species Act are at risk. The unintentional introduction of forest pest species and plant pathogens can change forest ecology and damage the timber industry . Overall, forest ecosystems in the U.S. are widely invaded by exotic pests, plants, and pathogens. The Asian long-horned beetle ( Anoplophora glabripennis ) was first introduced into

5537-621: The Americas after the United States , Canada , and The Bahamas , and has been one of the countries with the most improvement in Human Development Index ranking since 2015. According to the World Bank in 2023, very significant poverty still exists and the country faces significant risks in structurally managing its growth. The name "Guyana" derives from Guiana , an earlier name for a larger region that included

5650-483: The Atlantic coast (low coastal plain) where most of the population lives; a white sand belt further inland (hilly sand and clay region), containing most of Guyana's mineral deposits; the dense rain forests (Forested Highland Region) in the southern part of the country; the drier savannah areas in the south-west; and the smallest interior lowlands (interior savannah) consisting mostly of mountains that gradually rise to

5763-649: The Brazilian border. Some of Guyana's highest mountains are Mount Ayanganna (2,042 m or 6,699 ft), Monte Caburaí (1,465 m or 4,806 ft) and Mount Roraima (2,772 m or 9,094 ft – the highest mountain in Guyana) on the Brazil-Guyana-Venezuela tripoint border, part of the Pakaraima range. Mount Roraima and Guyana's table-top mountains ( tepuis ) are said to have been

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5876-524: The California sea otter ( Enhydra lutris ). Invasive species appear to have specific traits or specific combinations of traits that allow them to outcompete native species . In some cases, the competition is about rates of growth and reproduction. In other cases, species interact with each other more directly. One study found that 86% of invasive species could be identified from such traits alone. Another study found that invasive species often had only

5989-645: The Caribbean islands. The Arawak, mainly cultivators, hunters, and fishermen, migrated to the Caribbean islands before the Carib and settled throughout the region. Although Christopher Columbus was the first European to sight Guyana during his third voyage (in 1498), and Sir Walter Raleigh wrote an account in 1596, the Dutch were the first Europeans to establish colonies: Pomeroon (1581), Essequibo (1616), Berbice (1627), and Demerara (1752). After France invaded

6102-498: The Chinese mitten crab ( Eriocheir sinensis ) have resulted in higher bioturbation and bioerosion rates. A native species can become harmful and effectively invasive to its native environment after human alterations to its food web . This has been the case with the purple sea urchin ( Strongylocentrotus purpuratus ), which has decimated kelp forests along the northern California coast due to overharvesting of its natural predator,

6215-603: The Dutch Republic ( 1795 ), the British assumed control in 1796, with the Dutch and British signing the London Convention in 1814 that ceded Demerara-Essequibo and Berbice to Britain. In 1831, the united colonies of Demerara-Essequibo and separate colony of Berbice together became a single British colony known as British Guiana . Since its independence in 1824, Venezuela has claimed the area of land to

6328-431: The Essequibo watershed support a remarkable diversity of fish and aquatic invertebrates, and are home to giant otters , capybaras , and several species of caimans . On land, large mammals, such as jaguars , tapirs , bush dogs , giant anteaters , and saki monkeys are still common. Over 800 species of birds have been reported from the region, and the reptile and amphibian faunas are similarly rich. In February 2004,

6441-726: The Government of Guyana issued a title to more than 4,000 km (1 × 10 ^ acres) of land in the Konashen Indigenous District as the Kanashen Community-Owned Conservation Area, managed by the Wai Wai , and the world's largest community-owned conservation Area. The Iwokrama International Centre for Rain Forest Conservation and Development was also created for the protection and sustainable use of

6554-708: The Guiana Shield: The north-central part of the Guiana Highlands is dominated by high flat-topped peaks called tepuis , of the Roraima supergroup and Quasi-Roraima formation, and the rounded granite peaks of the Parguaza and Imataca complexes to the north and southwestern edges of the area. The highest point in the shield is Pico da Neblina in Brazil at 2,995 metres (9,826 ft). Pico da Neblina

6667-461: The Iwokrama forest area. Since 2009, Guyana and Norway have collaborated to promote green development in Guyana while keeping deforestation at low levels. The main economic activities in Guyana are agriculture (rice and Demerara sugar ), bauxite and gold mining, timber, seafood, minerals, crude oil and natural gas. The discovery of major crude oil reserves off the Atlantic coast has since made

6780-706: The Lokono and Kalina tribes, Guyana was colonised by the Dutch before coming under British control in the late 18th century. It was governed as British Guiana with a mostly plantation-style economy until the 1950s. It gained independence in 1966 and officially became a republic within the Commonwealth of Nations in 1970. The legacy of British colonialism is reflected in the country's political administration, lingua franca and diverse population, which includes Indian , African , Indigenous , Chinese , Portuguese , other European , and various multiracial groups. Guyana

6893-697: The South Indian states of Tamil Nadu and Andhra Pradesh ; these are the plurality ancestry in the East Berbice-Corentyne region. The two largest groups, the Indo-Guyanese and Afro-Guyanese, have experienced some racial tension. English is the official language of Guyana and is used for education, government, media, and services. The vast majority of the population speaks Guyanese Creole , an English-based creole with slight African, Indian, and Amerindian influences, as their first language. Invasive species An invasive species

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7006-522: The U.S. A decline in pollinator services and loss of fruit production has been caused by honey bees infected by the invasive varroa mite . Introduced rats ( Rattus rattus and R. norvegicus ) have become serious pests on farms, destroying stored grains. The introduction of leaf miner flies ( Agromyzidae ), including the American serpentine leaf miner ( Liriomyza trifolii ), to California has caused losses in California's floriculture industry, as

7119-549: The U.S. in 1996, and was expected to infect and damage millions of acres of hardwood trees. As of 2005 thirty million dollars had been spent in attempts to eradicate this pest and protect millions of trees in the affected regions. The woolly adelgid has inflicted damage on old-growth spruce, fir and hemlock forests and damages the Christmas tree industry. Chestnut blight and Dutch elm disease are plant pathogens with serious impacts. Garlic mustard, Alliaria petiolata ,

7232-801: The UNESCO World Heritage Site Central Suriname Nature Reserve of Suriname , the Guiana Amazonian Park in French Guiana and the Tumucumaque National Park in the Amapá State of Brazil . In Venezuela the forests are protected by Canaima , Parima-Tapirapeco and Serranía de la Neblina national parks. In 2014, the Government of Colombia designated a 250 hectare area of the Guiana Shield, as

7345-456: The Union of South American Nations. The Guyanese government officially ratified the treaty in 2010. In March 2020, President David A. Granger narrowly lost the snap elections , following Granger's government loss of a vote of no confidence back in 2018. Granger refused to accept the results, but eventually five months later, Irfaan Ali of the People's Progressive Party/Civic was sworn in as

7458-729: The United Kingdom as a dominion on 26 May 1966 and became a republic on 23 February 1970, remaining a member of the Commonwealth . Shortly after independence, Venezuela began to take diplomatic, economic, and military action against Guyana to enforce its territorial claim to the Essequibo region . Five months after Guyana's independence, in October 1966, Venezuelan troops crossed the international border and seized Ankoko Island which has been under occupation ever since. Venezuelan troops quickly constructed military installations and an airstrip. Following independence, Forbes Burnham of

7571-591: The alteration in ecosystem functionality (due to homogenization of biota communities), invasive species have resulted in negative effects on human well-being, which includes reduced resource availability, unrestrained spread of human diseases, recreational and educational activities, and tourism. Alien species have caused diseases including human immunodeficiency virus (HIV), monkey pox , and severe acute respiratory syndrome (SARS). Invasive species and accompanying control efforts can have long term public health implications. For instance, pesticides applied to treat

7684-621: The ancestors of Equus ferus (modern horses) evolved in North America and radiated to Eurasia before becoming extinct in North America. Upon being introduced to North America in 1493 by Spanish conquistadors , it is debatable whether the feral horses were native or exotic to the continent of their evolutionary ancestors. While invasive species can be studied within many subfields of biology, most research on invasive organisms has been in ecology and biogeography . Much of

7797-677: The areas now called Guyana ( British Guyana ), Suriname ( Dutch Guiana ), French Guiana , the Guayana Region in Venezuela ( Spanish Guyana ), and Amapá in Brazil ( Portuguese Guiana ). According to the Oxford English Dictionary , the name "Guyana" comes from an indigenous Amerindian language and means "land of many waters". The word Co‑operative in the official name refers to co-operative socialism . What

7910-478: The availability of resources determines the impact of additional species on the ecosystem. Stable ecosystems have a resource equilibrium, which can be changed fundamentally by the arrival of invasive species. When changes such as a forest fire occur, normal ecological succession favors native grasses and forbs . An introduced species that can spread faster than natives can outcompete native species for food, squeezing them out. Nitrogen and phosphorus are often

8023-467: The behaviour of herbivores , impacting on other species. Some, like Kalanchoe daigremontana , produce allelopathic compounds that inhibit competitors. Others like Stapelia gigantea facilitate the growth of seedlings of other species in arid environments by providing appropriate microclimates and preventing herbivores from eating seedlings. Changes in fire regimens are another form of facilitation. Bromus tectorum , originally from Eurasia,

8136-507: The business-as-usual scenario (which is important as Cape Town experiences significant water scarcity ). This is the equivalent to one-sixth of the city's current supply needs. These annual gains will double within 30 years. The catchment restoration is significantly more cost-effective then other water augmentation solutions (1/10 the unit cost of alternative options). A water fund has been established, and these exotic species are being eradicated. Invasive species can affect human health. With

8249-501: The colonies of the territory were merged and the land was given over to the British Empire in 1814. Upon emancipation in 1838, almost all of the former slaves abandoned the plantations, and Indians were brought to the country under indenture contracts from 1838 until the end of the system in 1917. The production of balatá (natural latex ) was once a big business in Guyana. Most of the balatá bleeding in Guyana took place in

8362-616: The completion of the first off-shore oil project. Actual growth in GDP in 2020 was 43%; reports in April 2021 anticipate 20% growth for 2021. The government initiated a major overhaul of the tax code in early 2007. A Value Added Tax (VAT) replaced six different taxes. Prior to the implementation of the VAT, it had been relatively easy to evade sales tax, and many businesses were in violation of tax code. Many businesses opposed VAT introduction because of

8475-511: The densities of native forage plants, declining the habitat-use by wild herbivores and threatening the long-term sustenance of dependent carnivores, including the tiger . Invasive species can change the functions of ecosystems. For example, invasive plants can alter the fire regime (cheatgrass, Bromus tectorum ), nutrient cycling (smooth cordgrass Spartina alterniflora ), and hydrology ( Tamarix ) in native ecosystems. Invasive species that are closely related to rare native species have

8588-528: The descendants of indentured labourers from India who make up 43.5% of the population, according to the 2002 census. They are followed by the Afro-Guyanese , the descendants of enslaved people brought from Africa, primarily West Africa , who constitute 30.2%. The Guyanese of mixed heritage make up 16.7%. The Indigenous peoples, known locally as Amerindians , make up 10.5% of the population. The nine Indigenous nations in Guyana, defined by language, are

8701-445: The economy under nationalisation was plagued by problems; political instability leading to an exodus of skilled labour, inexperienced management, aging infrastructure. Poor international market conditions also expanded the country's debt. The Guyanese economy rebounded slightly and exhibited moderate economic growth after 1999, due to expansion in the agricultural and mining sectors, a more favourable atmosphere for business initiatives,

8814-436: The expense to monitor, control, manage, and research invasive weed species is approximately AU$ 116.4 million per year, with costs directed solely to central and local government. While in some cases, invasive species may offer economic benefits, such as the potential for commercial forestry from invasive trees, these benefits are generally overshadowed by the substantial costs associated with biological invasions. In most cases,

8927-401: The extra paperwork required; however, the Government has remained firm on the VAT. Replacing several taxes with one flat tax rate, it will also be easier for government auditors to spot embezzlement . The large majority (about 90%) of Guyana's 744,000 people live along a narrow coastal strip that ranges from a width of 16 to 64 km (10 to 40 mi) inland and makes up approximately 10% of

9040-563: The field lacks any official designation but is commonly referred to as "invasion ecology" or more generally "invasion biology". This lack of standard terminology has arisen due to the interdisciplinary nature of the field which borrows terms from disciplines such as agriculture , zoology , and pathology , as well as due to studies being performed in isolation. In an attempt to avoid the ambiguous, subjective, and pejorative vocabulary that so often accompanies discussion of invasive species even in scientific papers, Colautti and MacIsaac proposed

9153-528: The first Guyanese election since 1964 to be internationally recognised as free and fair. Cheddi Jagan of the PPP was elected and sworn in as president on 9 October 1992. This reversed the monopoly that Afro-Guyanese traditionally had over Guyanese politics. The poll was marred by violence however. In May 2008, President Bharrat Jagdeo was a signatory to the UNASUR Constitutive Treaty of

9266-629: The fishing industry and have helped cause the collapse of the population of some species. Economic costs from invasive species can be separated into direct costs through production loss in agriculture and forestry, and management costs. Estimated damage and control costs of invasive species in the U.S. amount to more than $ 138 billion annually. Economic losses can occur through loss of recreational and tourism revenues. When economic costs of invasions are calculated as production loss and management costs, they are low because they do not consider environmental damage; if monetary values were assigned to

9379-630: The foothills of the Kanuku Mountains in the Rupununi savannah . Early exploitation also took place in the North West District, but most of the trees in the area were destroyed by illicit bleeding methods that involved cutting down the trees rather than making incisions in them. Uses of balatá included the making of cricket balls , temporary dental fillings, and the crafting of figurines and other decorative items (particularly by

9492-446: The governments of California and New Zealand have announced more stringent control for vessel hull fouling within their respective jurisdictions. Another vector of non-native aquatic species is ballast water taken up at sea and released in port by transoceanic vessels. Some 10,000 species are transported via ballast water each day. Many of these are harmful. For example, freshwater zebra mussels from Eurasia most likely reached

9605-489: The individual to its environment. Pre-adaptations and evolution after the introduction reinforce the success of the introduced species. The enemy release hypothesis states that evolution leads to ecological balance in every ecosystem. No single species can occupy a majority of an ecosystem due to the presences of competitors, predators, and diseases. Introduced species moved to a novel habitat can become invasive, with rapid population growth, when these controls do not exist in

9718-493: The inspiration for Sir Arthur Conan Doyle 's 1912 novel The Lost World . There are also many volcanic escarpments and waterfalls, including Kaieteur Falls which is believed to be the largest single-drop waterfall in the world by volume. North of the Rupununi River lies the Rupununi savannah , south of which lie the Kanuku Mountains . The four longest rivers are the Essequibo at 1,010 km (628 mi) long,

9831-636: The introductions of the amethyst gem clam and the European green crab . The gem clam was introduced into California's Bodega Harbor from the US East Coast a century ago. On its own, it never displaced native clams ( Nutricola spp.). In the mid-1990s, the introduction of the European green crab resulted in an increase of the amethyst gem at the expense of the native clams. In India, multiple invasive plants have invaded 66% of natural areas, reducing

9944-538: The invaded habitats and bioregions adversely, causing ecological, environmental, or economic damage. The European Union defines "Invasive Alien Species" as those that are outside their natural distribution area, and that threaten biological diversity . Biotic invasion is one of the five top drivers for global biodiversity loss , and is increasing because of tourism and globalization . This may be particularly true in inadequately regulated fresh water systems, though quarantines and ballast water rules have improved

10057-646: The invasive brown tree snake . In New Zealand the first invasive species were the dogs and rats brought by Polynesian settlers around 1300. These and other introductions devastated endemic New Zealand species. The colonization of Madagascar brought similar harm to its ecosystems. Logging has caused harm directly by destroying habitat, and has allowed non-native species such as prickly pear and silver wattle to invade. The water hyacinth forms dense mats on water surfaces, limiting light penetration and hence harming aquatic organisms, and causing substantial management costs. The shrub lantana ( Lantana camara )

10170-443: The limiting factors in these situations. Every species occupies an ecological niche in its native ecosystem; some species fill large and varied roles, while others are highly specialized. Invading species may occupy unused niches, or create new ones. For example, edge effects describe what happens when part of an ecosystem is disturbed, as when land is cleared for agriculture . The boundary between remaining undisturbed habitat and

10283-576: The local peoples in order to maintain successful settlements. After the initial rush to find gold in the New World waned, the Dutch found the climate to be suitable for growing sugar cane, converting large tracts of the Guyanese coast into plantations and supplying with labour from the Atlantic slave trade . The country and economy were run by a small European planter elite which continued on when

10396-738: The most notably famous are the Arapaima , which is the world's largest scaled freshwater fish; the giant anteater , the largest anteater; the giant otter , the world's largest and rarest river otter; and the Guianan cock-of-the-rock bird ( Rupicola rupicola ). The following habitats have been categorised for Guyana: coastal, marine, littoral, estuarine, palustrine, mangrove, riverine, lacustrine, swamp, savanna, white sand forest, brown sand forest, montane, cloud forest, moist lowland and dry evergreen scrub forests (NBAP, 1999). About 14 areas of biological interest have been identified as possible hotspots for

10509-474: The nation's total land area. Guyana's population is racially and ethnically heterogeneous, with ethnic groups originating from India, Africa, Europe, and China, as well as Indigenous peoples . Despite their diverse ethnic backgrounds, most groups share a common language of English and its Guyanese English Creole vernacular. The largest ethnic group is the Indo-Guyanese (also known as East Indians ),

10622-635: The new ecosystem. Non-native species have many vectors , but most are associated with human activity. Natural range extensions are common, but humans often carry specimens faster and over greater distances than natural forces. An early human vector occurred when prehistoric humans introduced the Pacific rat ( Rattus exulans ) to Polynesia. Vectors include plants or seeds imported for horticulture . The pet trade moves animals across borders, where they can escape and become invasive. Organisms stow away on transport vehicles. Incidental human assisted transfer

10735-523: The new environment may host fewer able competitors, allowing the invader to proliferate. Ecosystems used to their fullest capacity by native species can be modeled as zero-sum systems, in which any gain for the invader is a loss for the native. However, such unilateral competitive superiority (and extinction of native species with increased populations of the invader) is not the rule. An invasive species might be able to use resources previously unavailable to native species, such as deep water accessed by

10848-507: The new president because of allegations of fraud and irregularities. The National Trust of Guyana has designated nine historic sites as national monuments. A referendum in neighbouring Venezuela was held in December 2023 on the annexation of the disputed Essequibo region , which lies entirely in the territory of Guyana. The vote passed with a 95% majority, but with a low turnout, with analysts stating Maduro's government had falsified

10961-528: The newly cleared land itself forms a distinct habitat, creating new winners and losers and possibly hosting species that would not thrive outside the boundary habitat. In 1958, Charles S. Elton claimed that ecosystems with higher species diversity were less subject to invasive species because fewer niches remained unoccupied. Other ecologists later pointed to highly diverse, but heavily invaded ecosystems, arguing that ecosystems with high species diversity were more susceptible to invasion. This debate hinged on

11074-476: The pathways of hundreds of marine invasive species and found that shipping was the dominant mechanism for the transfer of invasive species. Many marine organisms can attach themselves to vessel hulls. Such organisms are easily transported from one body of water to another, and are a significant risk factor for a biological invasion event. Controlling for vessel hull fouling is voluntary and there are no regulations currently in place to manage hull fouling. However,

11187-472: The potential to hybridize with the native species. Harmful effects of hybridization have led to a decline and even extinction of native species. For example, hybridization with introduced cordgrass, Spartina alterniflora , threatens the existence of California cordgrass ( Spartina foliosa ) in San Francisco Bay . Invasive species cause competition for native species and because of this 400 of

11300-413: The results. This came at the same time as a Venezuelan military buildup on the Guyanese border, sparking concerns of war between the two states. The territory controlled by Guyana lies between latitudes 1° and 9°N , and longitudes 56° and 62°W ; it is one of the world's most sparsely populated countries. The country can be divided into five natural regions: a narrow and fertile marshy plain along

11413-678: The shield consist of Archean Imataca Complex, composed of a quartz - feldspar gneiss and subordinate mafic gneiss. The Guri Fault marks the southern boundary of the complex. South of that fault are Early Proterozoic rocks consisting of the metavolcanic Pastora Supergroup and the granitic plutonic Supamo Complex. The Cuchivero Group consists of ash flow tuff and granitic plutonic rocks. The Early to Middle Proterozoic Roraima Group consists of continental clastic sedimentary rocks. These Precambrian sediments include quartz sandstones , quartzites , and conglomerates presumed to be 1.8 to 1.4 Ga in age. There are three upland areas of

11526-412: The situation. Invasive species may drive local native species to extinction via competitive exclusion, niche displacement, or hybridisation with related native species. Therefore, besides their economic ramifications, alien invasions may result in extensive changes in the structure, composition and global distribution of the biota at sites of introduction, leading ultimately to the homogenisation of

11639-562: The spread of biological invasions, mitigate further impacts, and restore affected ecosystems. For example, the damage caused by 79 invasive species between 1906 and 1991 in the United States has been estimated at US$ 120 billion. Similarly, in China , invasive species have been reported to reduce the country's gross domestic product (GDP) by 1.36% per year. The management of biological invasions can be costly. In Australia , for instance,

11752-711: The subset of established non-native alien or naturalized species that are a threat to native species and biodiversity. The term "invasive" is poorly defined and often very subjective. Invasive species may be plants, animals, fungi, and microbes; some include native species that have invaded human habitats such as farms and landscapes. Some broaden the term to include indigenous or "native" species that have colonized natural areas. Some sources name Homo sapiens as an invasive species, but broad appreciation of human learning capacity and their behavioral potential and plasticity may argue against any such fixed categorization. The definition of "native" can be controversial. For example,

11865-471: The very low human population density of the area, most of these forests are still intact. The Smithsonian Institution has identified nearly 2,700 species of plants from this region, representing 239 distinct families, and there are certainly additional species still to be recorded. The diversity of plants supports diverse animal life, recently documented by a biological survey organised by Conservation International . The reportedly clean, unpolluted waters of

11978-760: The west of the Essequibo River . Simón Bolívar wrote to the British government warning against the Berbice and Demerara settlers settling on land which the Venezuelans, as assumed heirs of Spanish claims on the area dating to the 16th century, claimed was theirs. In 1899, an international tribunal ruled that the land belonged to Great Britain. From the Anglo-Dutch Treaty of 1814 , the British inherited Dutch territory which included lands between

12091-502: The work has been influenced by Charles Elton's 1958 book The Ecology of Invasion by Animals and Plants which creates a generalized picture of biological invasions. Studies remained sparse until the 1990s. This research, largely field observational studies, has disproportionately been concerned with terrestrial plants . The rapid growth of the field has driven a need to standardize the language used to describe invasive species and events. Despite this, little standard terminology exists;

12204-418: The world's fastest-growing economy. As it is said to have 11 billion barrels in oil reserves, the country is set to become one of the largest per capita oil producers in the world by 2025. The discovery of over 11 billion barrels of oil reserves off the coast of Guyana since 2017 is the largest addition to global oil reserves since the 1970s. Guyana is now ranked as having the fourth-highest GDP per capita in

12317-405: The world's fauna and flora and the loss of biodiversity . It is difficult to unequivocally attribute extinctions to a species invasion, though there is for example strong evidence that the extinction of about 90 amphibian species was caused by the chytrid fungus spread by international trade. Multiple successive introductions of different non-native species can worsen the total effect, as with

12430-421: Was described by early explorers Sir Walter Raleigh and Charles Waterton and later by naturalists Sir David Attenborough and Gerald Durrell . Southern Guyana is host to some of the most pristine expanses of evergreen forests in the northern part of South America. Most of the forests found are tall, evergreen hill-land and lower montane forests, with large expanses of flooded forest along major rivers. Thanks to

12543-567: Was elected three times as a member of the UN Security Council in 1975–76, 1982–83 and 2024–25. In 1978, a total of 918 people died at the Jonestown mass murder-suicide led by American cult leader Jim Jones at a remote settlement in northwest Guyana. Former U.S. President Jimmy Carter visited Guyana to lobby for the resumption of free elections. On 5 October 1992, a new National Assembly and regional councils were elected in

12656-416: Was estimated to exceed $ 423 billion annually as of 2019. This cost has exhibited a significant increase, quadrupling every decade since 1970, underscoring the escalating financial implications of these biological invasions. Invasive species contribute to ecological degradation , altering ecosystem functionality and reducing the services ecosystems provide. This necessitates additional expenditures to control

12769-470: Was introduced in the San Francisco Bay and hybridized with native Spartina foliosa . The higher pollen count and male fitness of the invading species resulted in introgression that threatened the native populations due to lower pollen counts and lower viability of the native species. Reduction in fitness is not always apparent from morphological observations alone. Some degree of gene flow

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