As time goes by, we seem to become more and more aware of our surroundings. We start to understand the world around us and our place in society, especially the link between us and nature. Nature holds a very fragile place in the world and must hold a balance with modern society. But what happens when this delicate balance is thrown off? Invasive species (as understood from its name) are invaders of nature. They can take over anything they are exposed to and are difficult to control. Even though controlling these species is difficult, it can be beneficial to introduce invasive species to a new area. Government agencies and businesses must take careful thought into whether or not to transfer an invasive species to another country. To make an educated decision they must consider the benefits that the species will bring, if the species can be controlled, and the risk that comes with introducing the invader to a new location.
Invasive species usually have a bad name attached to them. Their reputation is filled with negativity and is known to simply be unwanted. However, government agencies and businesses should consider all the benefits of introducing these species to new areas. With the aid of a new species in a controlled environment, the economy can take a turn for the better. Farming oceans is an up-and-coming trade that brings many benefits such as “food security and poverty alleviation” to countries around the world (Source C). These underwater farms- commonly known as Aquaculture- also create many new jobs that help developing countries. The underwater farmers offer “a wide range of options for diversification of avenues for enhanced food production and income generation in many rural and peri-urban areas” by farming many different species not common to the area. Though introducing new species to different locations can cause problems, the benefits should always be considered with an open mind.
Control is the fragile barrier between success and chaos. And this barrier brings order to situations that would otherwise run themselves to destruction. Invasive species are particularly familiar with the destruction that comes from lack of control, and therefore the ability to control must be considered when transferring invasive species to new regions. Invasive species can be introduced intentionally or by accident. Either way, the species must be controlled before they cause catastrophic problems. When an invasive species is purposely introduced to a new region- even though the intentions may be good- the species itself can become a problem that affects many people and places. Dybas discusses the horrific effects caused by the accidental introduction of “SARS, a viral respiratory virus” to countries all over the world (Source B). She goes on to explain the many deaths that were caused by the virus and the extreme measures that had to be taken to try and control the invader. Once SARS became an uncontrolled pandemic, however, the virus spread like wildfire using “planes, trains, ships, and automobiles” (Source B). Most invasive species show traits much like SARS and can become a large problem if not properly controlled.
Taking a risk requires understanding the possible consequences and a leap of faith. Risks should not be confused with stupidity, because risks are always taken with a logical reason to obtain positive results. And by balancing the pros and cons of a situation, we can decide whether or not a risk is worth taking. Government agencies and businesses must also weigh their pros and cons to decide if introducing an invasive species to a new area is worth the risk. The positives are clear: employment opportunities, economic growth, decrease in food shortages. But what about the consequences? Ignorance of the risks of bringing in invasive species can lead to destruction as shown in Source A. The photo depicts a barren forest that instills a sense of loss and sadness, all because of an insect infestation. Even invasive species that seem to be a good idea come with consequences. Spotts discussed the cane toads becoming an invasive species in Australia even though “it seemed like a good idea at the time” (Source F). Toads that were originally supposed to battle beetles that attacked sugar-cane plants became invaders that spread throughout the entire continent, “munching on almost everything in sight” (Source F). If government agencies and businesses show no ignorance and are sure to understand the possible consequences, an educated decision can be made on whether or not to introduce an invasive species.
As humans, we like to be comfortable with the events that surround us. We like to know what is going on and have the power to control the outcome of a situation. Government agencies and businesses DO have to power to control whether or not to introduce an invasive species to a new area. And with this power, considerations must be made to make an educated decision. They must understand the benefits the species can bring to the new area, know how to control the species, and know of the consequences that come with introducing these species. And when all the considerations are made with a complete understanding of the invasive species, both ourselves and the world around us can benefit from the final decision.
Florida has one of the greatest invasive species problems in the United States. Many factors make the state particularly vulnerable to introduced species, including Florida’s subtropical climate, status as a transportation hub, pet industry, isolation, and susceptibility to natural disasters. This is a huge threat to native species—especially reptiles and amphibians who thrive in Florida’s climate. Along with changing competition and predation, invasive species may pose a threat to human safety, domestic animals, and the economics of management. Non-native lizard species have already taken over native breeding numbers threefold in South Florida. Despite the growing problem, there is a lack of public concern or risk assessments of potential invasiveness. The general public is mostly aware of the Burmese python in the Everglades but may not understand that invasive species are a widespread problem in the state. Three species of great risk are the cane toad (Rhinella marina), Argentine black and white tegu (Salvator merianae), and Northern African python (Python sebae sebae).
Cane toad
The cane toad is a large species of toad, reaching approximately six to nine inches long (Florida Fish and Wildlife Conservation Commission, 2019). It is usually brown with no distinct pattern on its underbelly, and the parotid glands are very pronounced and can produce toxins (Makowski and Finkl, 2018). Cane toads strongly resemble the Southern toad (Anaxyrus terrestris); however, the cane toad is significantly larger (Florida Fish and Wildlife Conservation Commission, 2019). This species is native to Central and South America, ranging from the Rio Grande to the Amazon River basin (Florida Fish and Wildlife Conservation Commission, 2019). Cane toads are omnivorous, eating insects, vegetation, and small vertebrates, including native amphibians (Florida Fish and Wildlife Conservation Commission, 2019). They breed during the wet season, specifically from June through October (Makowski and Finkl, 2018). Their habitats include a variety of man-made and natural habitats, such as drainage ditches, ephemeral ponds, and other shallow bodies of water (Makowski and Finkl, 2018).
Cane toads were initially released in the 1930s as a pest control method for agriculture (Makowski and Finkl, 2018). The most impactful releases occurred in the 1950s in Miami, starting when a pet dealer accidentally released cane toads at an airport, followed by several more intentional releases soon after (Makowski and Finkl, 2018). Since these releases, the cane toads have expanded their range to the entirety of southern Florida (Florida Fish and Wildlife Conservation Commission, 2019).
As global temperatures increase, the range of the cane toad in Florida may expand northward (Makowski and Finkl, 2018). A large threat to native wildlife is the toxins secreted by the cane toad’s large parotid glands (Florida Fish and Wildlife Conservation Commission, 2019). Red-tailed hawks and American crows have begun to flip over toads when eating them to avoid the parotid glands (Wilson and Johnson, 2017). In addition to poisonous secretions from the parotid glands, toxins in cane toad eggs can poison native tadpoles (Florida Fish and Wildlife Conservation Commission, 2019). In one study, cane toad tadpoles only outcompeted native tadpoles when other species of invasive tadpoles were present (Smith, 2005). However, there is still concern about adult cane toads outcompeting adult native frogs (Makowski and Finkl, 2018). Cane toads regularly consume small vertebrates and could affect native populations of rodents, frogs, and small reptiles (Makowski and Finkl, 2018). The current impact of cane toads on native Floridian ecosystems is so far less than the impact on Australian impacts, but those populations were started larger earlier on (Makowski and Finkl, 2018).
Argentine black and white tegu
The Argentine black and white tegu is a large, omnivorous lizard weighing up to eight kilograms and reaching over one and a half meters in length (Engeman et al., 2011; McEachern et al., 2015). They are characterized by beaded scales and a stripe of light spots or dashes. The species exhibits sexual dimorphism with males growing larger than females. The lizard is primarily terrestrial but is also an adept swimmer and active burrower. Black and white tegus are habitat generalists, living in tropical, subtropical, and temperate climates. They utilize both disturbed and undisturbed forested and open natural areas. Their omnivorous diet consists of everything from vegetation, fruits, carrion, small mammals, and reptile eggs. Rotting vertebrates are the lizard’s main food source in its native range. It mainly uses chemical cues to find food but also a vision for prey; these chemical cues are what allow the tegus to find nests and dig up eggs to eat. Tegus lay a single clutch of twenty to forty-five eggs per year in the spring starting at age three or four (Engeman et al., 2011). Some studies show that they use other species’ burrows for their eggs. Independent offspring hatch after sixty-five to seventy-five days of incubation with parental care being shown through female egg defense and male territoriality (Chamut et al., 2012).
The native range for tegus is extensive, ranging from northern Patagonia, north to the Amazon forest, and west to the Andes Mountains. They are found in the microhabitats of Gran Chaco, Caatinga, Cerrado, Pampas, and the Atlantic Forest. 7,700 live Black and White tegus were shipped from Paraguay from 2000 to 2002 for the pet trade (McEachern et al., 2015). The tegus all had defects and may have been released to establish a population for exploitation or to avoid killing unwanted animals. By 2002, a free-ranging tegu was established in Florida. These are earlier dates recorded, but these are from less credible sources. Overall, there seems to be disagreement on the origin timeline of the tegu establishment. As seen in Figure 1, Hillsborough, Polk, and Miami-Dade counties now have populations. The Florida City and Southern Glades Wildlife and Environmental Area is the current center of the populations, but the southwest is not safe from spread; this area is only six miles away from Everglades National Park, and tegus have already been seen west of the Everglades Agricultural Area (Harvey and Mazzotti, 2015). Hurricanes may increase the spread of tegus as they can damage enclosures and release pets. Argentine black and white tegus have been described as doglike because they are intelligent and can be house-broken. Trying to manage, and possibly lethally control, a species considered to be a pet may cause controversy.
With global warming, small and localized populations in southeast Florida could reproduce and spread with better conditions. This is especially worrying, as the population is very close to Everglades National Park already. Climate change also increases the likelihood of natural disasters and drastic temperature changes. This would increase the potential for escaped pet tegus. Argentine black and white tegus can also survive drastic climate events brought on by climate change that other species cannot. They practice winter dormancy in underground burrows called brumation. Tegus brumate for an average of 137 days and could “wait out” hard winters (McEachern et al., 2015). By using other species’ burrows, tegus could additionally threaten native species, such as gopher tortoises and burrowing owls. They have been documented predating on the nests of Florida red-bellied cooters and American alligators. Figure 2 shows the first evidence of this in a camera trap study. Populations are approaching a nesting area of federally threatened American crocodiles in the east and American alligators in the west and south. The native diet of the species supports the threat towards crocodilians; tegus are the main predators of spectacled caiman eggs in the Venezuelan Llanos. Gut studies have shown that tegus have preyed on the native cotton rat, a similar species to the endangered Key Largo woodrat (Harvey and Mazzotti, 2015). The varied diet of tegus poses a threat to federal and state-listed reptiles, birds, and even mammals.
Northern African python
The Northern African python is a large snake with dark blotches or spots; their scales are entire and sometimes fused. They are considered a giant snake species, ranging from three to six meters long. They prefer evergreen forests or moist savannahs in their native range and tend to live near rocky areas and water. Their climate niche ranges from fifteen to thirty-five degrees Celsius (Reed and Rodda, 2009). The python also thrives in disturbed environments. This could include agricultural areas, canals, farm fields, or towns. When living near humans, they can adjust their natural diurnality to nocturnality to avoid conflict. They predate on a variety of endothermic prey through constriction—mainly rodents or abundant domestic animals. The python has also been observed consuming lizards, fish, crocodiles, and frogs. Mating can occur during varying seasons or be year-round depending on the location; about twenty to fifty eggs are laid in hollow trees, termite nests, or mammal holes (Reed and Rodda, 2009). The females show maternal care by coiling around the eggs and incubating them. This is a very rare parental care attribute in snakes and is only seen in pythons. The eggs incubate for fifty-seven to sixty-one days or longer in lower temperatures (Branch and Patterson, 1975). For this species, there may be potential for hybridization with the invasive Burmese python. Genetic diversity studies show that Burmese pythons and Indian pythons are likely to have been hybridizing in the wild for years, and hybridization with the Northern African python has been observed in captivity (Hunter et al., 2018). This could cause hybrid vigor, or the increased diversity, fitness, and fecundity of future populations. Burmese pythons are arguably the most damaging invasive species in Florida currently. Their range is extensive, and breeding with the more constrained in-range Northern African python would only increase their spread.
Northern African pythons natively inhabit the coasts of Kenya and Tanzania, across much of central Africa to Mali and Mauritania, and north to Ethiopia and Eritrea. Their range can be seen in Figure 3. There are uncertainties in this data denoted with question marks. Before the species was subdivided, feral rock pythons were seen in the Everglades in the 1990s (Murphy and Henderson, 1997). The earliest recorded Northern African python in Florida was seen around 2001 to 2005, and they are now in the counties of Miami-Dade and Sarasota with an established population in the former (Krykso et al. 2011). Credible sightings of different age classes show evidence of a breeding population. Their spread is thought to be due to released or escaped pets, as is with most of Florida’s invasive species. The export of Northern African pythons is lower than other snakes at an average of 1,056 per year, but the damage to Florida has already been done (Luiselli et al., 2011). Further, African pythons may be able to inhabit populations north of their climate limit.
The range for the Northern African python is expected to increase with global warming. Breeding populations are currently restricted to warmer climates due to egg incubation, but with increasing temperatures, they could move further north. When the temperature is low, and thus the incubating female is too cold, python eggs either don’t hatch or hatch deformed. Because of this, warmer temperatures brought on by climate change would increase reproductive success for the python. The pythons are restricted to a small area in Florida, but they are already threatening humans and native fauna. Attacks of Northern African pythons on humans are rare but existing. In 1979, a thirteen-year-old boy was constricted to death by the species in South Africa (Branch and Hacke, 1980). Rare as these stories are, they create myths and animosity for the species that muddle science and management. Native animals are the ones truly at risk. Wading birds such as wood storks are known to be prey, and many more are suspected to be (Johnson and McGarrity, 2017). As well as eating the Florida equivalents of their prey in Africa, the pythons spread diseases and parasites. African pythons have been shown to host several ticks: Amblyomma nuttalli, Amblyomma marmoreum, Amblyomma sparsum, Aponomma exornatum, Aponomma flavomaculatum, and Aponomma latum (Burridge, 2001). After being transported to the U.S., the ticks host-switch to native species; This has occurred with at least two species in Florida already. Some of the species are known or suspected to transmit mammalian heartwater disease, Q fever, and reptile haemogregarine parasites. Unfortunately, there is an inadequate amount of data on disease ecology to understand more specific impacts.
Conclusion
Florida is a hotspot for invasive species and is currently a threat to native populations. The high amount of invasive reptiles especially poses a threat to reptiles and amphibians. The cane toad has the potential to affect herpetofauna populations through its poison secretions and its consumption of vertebrates. The Argentine black and white tegu will affect future populations of crocodilians by eating their eggs. The African pythons are known for carrying diseases and parasites that could be transmitted to different taxa. Not only are invasive species a threat to native wildlife, but they also pose a risk to humans and domesticated animals. Climate change is likely to worsen the effects of invasive species in Florida as the temperatures rise, allowing easier establishment and movement of invasives. As native populations decline, invasive species will begin to fill their niche, making them harder to remove and potentially harming the ecosystem.
Lantana camara is an exotic weed that is distributed throughout the tropical and subtropical world regions (Holm et al 1997) it originated from Central and South America and was introduced into the Philippines from Hawaii and became naturalized. It was introduced as an ornamental plant for gardening because of its colorful flowers of different hybrids (pink, orange, and yellow) and it thrives well because of its tolerance to a wide array of environmental conditions and habitats with allelopathic chemicals in all its parts. It has efficient advantages over native species under conditions of light, soil moisture, and nutrients making it an efficient competitor. studies claim that the distribution of Lantana camara will likely expand in the future with projections most particularly to habitats where it has become established with suitable climatic conditions (Vardien et al 2012). Effective suppression of its proliferation is by preventing seed dispersal which will consequently inhibit both seed germination as well as seedling establishment resulting in declined productivity of the invasive weed.
In general, there are three known options for the control of an invasive species: chemical control, physical control, and biological control. Each of these has its pros and cons. No definite effective control measure has yet been found. Integrating all control options, the physical, mechanical, and biocontrol options depending on the scale of the weed infestation and to which control method can be feasible is suggested and will likely result in improved control and mitigation strategies. In addition, principles underpinning strategic control need collective action at all levels of governments, NGOs, and communities. Promoting community awareness about the negative impacts of Lantana’s invasion would optimize control success.
Introduction
Invasive Alien Species also known as exotic species are plant and animal species that are introduced to areas outside their natural geographic range wherein, they are not native or present by nature. Their introduction may be accidental or by purpose and consequently poses adverse ecological and economic impacts (Bruton and Meron 1985; De Silva 1989). As introduced to their non-native area, invasive species outcompete the existing native species in the area where they don’t have existing natural predators and proliferate. Another factor that contributes to their proliferation is the ecological suitability of the new habitat. Competition for resources, predation, niche displacement, hybridization, introgression and extinction (Mooney and Cleland 2001) are consequences faced by native species with their encounter with invasive species. Organism transport to a new habitat either between islands and countries, establishment and growth of the species the natural or man-made habitats, and the spread of the species to large areas at an uncontrolled rate are the introduction pathways of the exotic species. In the Philippines, some exotic species are for the production of food supply, reforestation projects, and horticulture. Today, people still lack awareness of the negative impacts of invasive species, and efforts to create invasive species awareness are needed.
This paper particularly highlights the species Lantana camara, an exotic weed that is distributed throughout the tropical and subtropical world regions (Holm et al 1997), originated from Central and South America and was introduced into the Philippines from Hawaii and became naturalized. It was introduced as an ornamental plant for gardening because of its colorful flowers of different hybrids (pink, orange, and yellow) and it thrives well because of its tolerance to heat. The species is considered one of the most invasive plant species in the Philippines (ISSG, 2006) as it invades both natural and agricultural ecosystems and reduces productivity. It has varied impacts ranging from ecological processes, and adverse effects to native plant diversity, and native disturbance regime alterations. Their impact on vegetation affects herbivores and carnivores that feed on them thereby threatening livestock. Lantana alters species composition of understory species and tree seedlings, and also it covers grass, understory vegetation, and tree seedlings free of herbivory, in turn increasing the lantana density beneath thickets – which will become denser when simply slashed or uprooted making it hard to eradicate (ECZ, 2004). The lantana can last in seed banks for several years then invade and eventually dominate forest understory. In addition, the plant is known to spread and infest rapidly with resistance to cutting and burning. In particular, it colonizes the gaps and edges of disturbed forests or logged habitats. The plant is also abundant and distributed in grass habitats due to the absence of shading effects and frequent former land use disturbances plant narrowed the size of farmlands and created difficulties in the cultivation of crops. The prickly impenetrable thickets of lantana, not only completely hinder the movement of animals, and prevent them from searching for food, but also puncture their skins and cause injury (Alemu and Terefe 2015). The weed is prone to the spread of fire and may consequently alter the fire regime in favor of its persistence (Hiremath & Sundaram 2005). The fire then causes the mortality of neighboring seeds and seedling mortality of other species in the area (Moore & Wein 1977). Inhibiting both seed germination as well as seedling establishment, resulting in declined productivity. Thus, this invasive weed species cover may create demographic instability among tree species consequently reducing tree diversity and changing forest structures in the future (Sharma 2010). Lantana populations were growing across all land uses. Its historical demography showed that weather (from El Nino to La Nina) had a strong influence on its demography having a strong positive effect on the population growth rate. In addition, Lantana camara inhibits the growth of species near it due to its allelopathic effects present in all its parts interfering with the germination of many species (Ambika 2003, Bais 2004, and Kumar 2011) of crops, weeds, bryophytes, and vegetables (Mishra, 2015). It is known to have efficient advantages over native species under conditions of light, soil moisture, and nutrients making it an efficient competitor. Allelopathy caused by lantana reduces early growth rates hence increasing mortality to other plant species (Sharma et al. 2005a, 2005b), resulting in overall decreased species diversity and cover (Gentle & Duggin 1998; Loyn & French 1991). Most studies claim that the distribution of Lantana camara will likely expand in the future with projections most particularly to habitats where it has become established with suitable climatic conditions (Vardien et al 2012). From this, we can derive strategic planning by biosecurity agencies, identifying areas to target for eradication or containment. Distribution maps of the risk of potential invasion can be useful tools in public awareness campaigns and effective responses be taken.
In general, there are three means of exotic species removal and it can done via mechanical, chemical, or biological control all of which can be applied to an integrated invasive species management plan (Williams and West, 2000). Mechanical or physical controls (like bulldozing and plowing) are effective and are suitable for moderate infestations. Thinning and pruning methods of control were also frequently used. However, eradication of a weed that has become established is costly (Bhagwat et al., 2012; McConnachie et al., 2012) and difficult (Baars & Heystek, 2003). As mentioned, lantana is difficult to eradicate because it will coppice and form thickets if simply removed via uprooting or slashing. The study of Toland et al, 2005 showed a significant relationship between forest gap in canopy and lantana pollinator visitation consequently facilitating the invasion of lantana and recommended a program for selective physical removal of L. camara individuals and that sprouting of its shoots should be removed continuously, such that flowering is prevented in the process. The secondary spread of L. camara will then be hindered by gaps in forest interiors.
Even with the widespread distribution of lantana, the costs of chemical and mechanical control, and its invasion of both agricultural and natural lands, its current management is mainly focused on the use of specialist insects and pathogens in efforts to find effective biocontrol of this weed (Day et al. 2003). The use of such biological control was claimed to be proven as a potentially cost-effective, and safe method for the management of invasive weeds. However, the host specificity, altitude, and seasonal preferences of released agents, the number of agents introduced, and the extent of the invaded area likely limit the success of biological control (Zalucki et al., 2007). Furthermore, no standard methods have been formulated for effective management of the species and it may be because of its occurrence in such a wide array of land uses and vegetation, where perceptions of the species, management goals, and resources present differ considerably. Suites of methods are often used, the particulars of which are dependent on the land use, extent and density of the invasive populations, accessibility to invaded areas, economic value of land, and the associated costs (Day et al, 2003). For an effective biological control agent, it may need to strongly limit the growth of juveniles into the adult stages, especially in sites where lantana is free from competition, like in fire and grazing, and they need to implement this specifically during wet years (Rhagu et al, 2014). Management of land use practices particularly as fire and grazing pressure should be noted regarding this. (Osunkoya, Perrett, Fernando, Clark, & Raghu2013).
Mitigation Framework
Presented below is a diagram showing the different control methods of the weed and each of its pros and cons. Each control method option has its pros and cons. Chemical control like the usage of herbicides is effective and yields definite damage to the invasive weed, nonlabor intensive and easy application yet the method is costly and may pose risks to human health and further cause environmental degradation. The physical or mechanical control is effective and suitable to levels of medium-sized infestations only and is not feasible for large-scale infestations for it will be costly and labor intensive. Lastly, biological control is the natural and safer control option that is efficient and applicable to large-scale invasions. On the downside, introduced biological agents are not fully successful due to host specificity because of the lantana hybridization and no phytophagous agents have been introduced yet. Also, agents have differing altitude and seasonal preferences, so they vary across habitats land use types, and climate regimes. Research on effective biocontrol agents is still ongoing.
To sum it all up, coming up with a long-term and sustainable control of the invasive lantana weed is suggested that the benefits and adverse impacts should be resolved through proper management options integrating the physical mechanical, and biocontrol options depending on the scale of the weed infestation and to which control method can be feasible. Secondly, the principles underpinning strategic control need collective action at all levels of governments, NGOs, and communities. Promoting community awareness about the negative impacts of Lantana’s invasion would optimize control success. Moreover, integration of such techniques will likely result in improved control and mitigation strategies.
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Biodiversity refers to the variety of animals, plants, fungi, and even microbes such as bacteria that make up our natural world. Each of these species and organisms work together in ecosystems to preserve balance and support life, much like an endless chain. In addition, it includes the number and variety of organisms within a defined area. Furthermore, Biodiversity supports everything in nature that we need to survive food, clean water, medicine, and shelter. There are three types of diversity; Genetic diversity refers to the total number of genetic features in a species’ genetic composition; it can range from the number of species to variances within species and can be linked to a species’ lifespan; Species diversity involves the number of various species present in an ecosystem, as well as their relative abundance, when all of the species present are equally abundant in the area, diversity is greatest; Lastly, Habitat diversity refers to the range of habitats present in a region.
One of the most significant effects of humans on nature has been an acceleration in the rate of extinction of species well beyond natural levels. This began thousands of years ago, and before the modern era, the loss of global biodiversity due to human activity was already significant. Extinction is on the rise, biodiversity is dwindling, and many ecosystem processes are deteriorating or disappearing. There were fewer than 1 billion people on the planet in 1800, and there are now approximately 6.8 billion. Even if it weren’t for the massive increases in per capita resource consumption that happened during this time, the pressures on biodiversity would have increased due to population expansion.
Climate change
Climate change refers to the long-term and irreversible change that occurs in the Earth’s climate. The increase in the temperature of the atmosphere has major effects on the environment including the weather, rising sea levels, rising CO2 levels, and melting of the polar ice caps. The key causes of rising CO2 emissions in terms of climate change are increased fossil fuel consumption in transportation, industry, and other sectors, as well as land use change and agriculture. These, in turn, are fuelled by rising income and the world’s growing population. Levels have already risen to roughly 417ppm in March 2021, a 50 percent increase above the average in 1750-1800 (Betts, 2021). Recent tragedies and catastrophic events have highlighted how biodiversity loss and climate change are inextricably linked. Tropical coral reefs, one of the most vulnerable and threatened ecosystems, are bleaching (losing color) regularly, and many species within them are dying off. This is due to more than just rising water temperatures. In the first place, these reefs were overfished, overharvested, or over-touristed, resulting in increasingly fragile reef systems that are unable to withstand the added stress of warming water. Another significant effect of climate change is ocean acidification. Oceans have absorbed half of the carbon dioxide produced by burning fossil fuels, but as carbon dioxide levels rise, ocean PH levels fall, causing corals to be unable to absorb the calcium carbonate required to maintain their skeletons and stony skeletons. Since 1751, the ocean has become at least 30% more acidic, with serious effects on the ocean’s biodiversity.
Pollution
Toxic industrial chemicals and pollutants released into the environment have a significant impact on species abundance and can lead to extinction. It’s vital to note that ‘natural’ elements can pollute when they become overabundant within a given location. Nitrogen and phosphorus, for example, are necessary minerals for plant growth, but when they accumulate in water systems after being applied as agricultural fertilizers, the habitats become unsuitable for fish and other wildlife. Furthermore, while carbon dioxide is a natural component of the atmosphere, it is classified as a pollution when generated by human industrial activities. Around 80% of nitrogen utilized by humans is wasted and pollutes the environment through food production, transportation, energy, and industrial and wastewater activities. Undetectable by eye, nitrogen pollution, as well as, conifer plantations, and deer all threaten the sustainability of the remaining 30,000 hectares of Scottish rainforest. Furthermore, air, water, and soil pollution have been seen to be rising in some areas, while marine plastic pollution has exponentially increased since 1980 which has affected 44% of seabirds (Greenfield and Weston, 2021). Nitrogen substances from intensive farming and fossil fuel combustion are thrown from the sky on Scotland’s rainforest, destroying lichen and bryophytes that absorb water from the air and are extremely sensitive to atmospheric conditions.
Habitat destruction
Changes in the environment that result in the loss of a certain habitat’s functional value are referred to as habitat loss. The habitat can no longer contain and sustain the lives of the organisms there, causing their population to decline. Habitat loss is mostly caused by industrial activities, agriculture, aquaculture, mining, deforestation, and water exploitation. This involves deforestation to obtain wood for cooking. Dams have fragmented the habitats of aquatic creatures. These habitat fragments may not be large or well-connected enough to support species that require a large territory to find mates and food. Migratory species struggle to find locations to rest and feed along their migration paths due to habitat loss and fragmentation. The deforestation of the Indonesian and Malaysian rainforests is one of the most extreme modern-day examples of habitat degradation. Humans are gradually but steadily removing the rainforests to make space for palm oil plantations and the extraction of precious wood resources. Rainforests are disappearing at an alarming rate all around the planet. The degradation of rainforests endangers iconic wildlife such as the orangutan, tiger, and Asian elephant (Wich et al., 2012). Oil spills can have a significant influence on seas, rivers, and other water sources; they can destroy ecosystems, particularly those in mangroves and coral reefs, while also disturbing the natural ecosystem that makes up these environments. Oil can harm, if not kill, birds, fish, and other sea life. For example, they may get coated in oil, impairing their ability to move, thermoregulate, and consume, or they may become entirely engulfed in oil slicks.
Invasive species
An exotic or unnatural species is any organism that has been introduced to a new habitat. This invasion can pose significant threats to native species, as they are frequently subjected to intense competition for resources, disease, and predation. Invasive species can disrupt an ecosystem by altering its habitat and depriving native creatures of food and resources. They may devour or infect native animals with diseases from which they are unable to protect themselves. In terms of nesting places and reproduction rates, they can also outcompete native species. This results in their dominance of the area and the extinction of native species. An example of an invasive species caused by predation is the brown tree snake. When this species was introduced to Guam (an island in the Pacific Ocean), it ate the eggs and young birds from the nests and wiped off 34 of the bird population (Zhang, 2017). The black rat, Rattus rattus, is most frequently associated with catastrophic bird reductions on islands they are one of the most common invading animals on islands and continents, and it is almost universal on Pacific islands, this species thrives in human-dominated habitats, natural areas, and also on islands uninhabited by humans. The Greater short-tailed bat, snipe, and wren were wiped out by the invasion of the black rat in 1962 (Bell and Merton, 2016). Plants can also contribute as an invasive species, Japanese knotweed has been shown to cause issues around it has been imported by Victorians as an ornamental plant in 1825 and is now prevalent throughout and a difficult plant to control (Fennell et al., 2018). In addition, Rhododendron ponticum is a well-established non-native invasive species endangering a wide range of natural and semi-natural habitats, as well as the associated flora and fauna. Rhododendrons are ubiquitous in woodlands and gardens they were first introduced in 1763 and are thought to be hazardous because they spread disease and restrict light from native plant species growing beneath. There is legislation implemented to restrict the growth of this place, The Wildlife and Countryside Act 1981 (Hulme et al., 2015).
Overexploitation
Overexploitation refers to the hunting of wild species at a higher rate than natural populations can recover. Overexploitation includes both overfishing and overhunting as examples. Some species may recover and avoid extinction if this is stopped early enough, although this is not always the case. A well-known example of a species that has experienced overexploitation is the Stellers sea cow, Hydrodamalis gigas. Hunters wiped out Steller’s sea cows fewer than 30 years after they were discovered by Arctic explorers in the 18th century. This species’ fat might be used for cooking as well as an odorless oil lamp, and the skin could be utilized to produce garments and boats. Butter could be made from the milk of the female Steller’s Sea cow. Fishing is one of the leading causes of population decreases in marine species. Fishing is not harmful to the ocean; nevertheless, when ships and boats harvest fish faster than the stock can recover, the species suffers, and, in certain cases, extinction occurs. The west coast of South America, off the coasts of Peru and Chile, was formerly home to the world’s greatest fisheries. Catches of Peruvian anchoveta exceeded 10 million tonnes along the coasts of northern and central Peru from the late 1960s to 1971. The Peruvian anchoveta population was severely exploited and collapsed during the 1972 El NiÃo warming. Due to technology advancements such as refrigeration, sonar power, and wider nets, ocean fisheries have been particularly prone to overharvesting in the post-WWII period. For hundreds of years, the cod fishery in the North-western Atlantic Ocean was an important commercial fishery, but only a few decades of intensive harvesting employing this new technology in the late twentieth century resulted in population collapse. The population has decreased by more than 90%, and fishing for the species has been prohibited in both Canada and the United States (Hutchings, 2005).
Solutions to threats
Even though the biodiversity of many habitats is under threat, there are numerous things we can do to help mitigate the threat. Nature preserves, often known as National Parks, are a type of government regulation. They protect a place and the animals that live in it from certain sorts of development and allow people to visit them. This is great since it maintains the natural habitat and serves as a viewing area for the ecosystems. In addition, invasive species are sometimes intentionally introduced into an area, but they are also sometimes introduced by accident. To reduce the number of invasive species accidentally transported, planes, ships, and cargo must be thoroughly inspected before being shipped to a new country. For habitat loss, organizations and companies can practice the reuse of paper and timber products that encourage deforestation. The restoration of species’ habitats by the planting of native vegetation and trees would allow species to reclaim their habitats and minimize the likelihood of their extinction.
Biodiversity, or the variety of living creatures in our world, has been decreasing rapidly, primarily due to a combination of man-made factors such as pollution, climate change, and land usage. Furthermore, climate change has been found to have a large impact on the earth’s biodiversity and to be the cause of numerous species extinctions, particularly in marine plantations. Moreover, habitat loss plays a significant part in the extinction of many species and can lead to the introduction of invasive species in new places, resulting in the loss of species that have been found to hurt biodiversity. There are now several solutions that have been implemented as a viable way of biodiversity protection, such as legislation presented by the government, the creation of nature preserves, a reduction in the number of invasive species, and the restoration of habitats.
The authors of the article chosen for the analysis focus on the problem of biodiversity and its connection to thiamine, also known as vitamin B1 deficiency. The reason for such discussion is the observation that many wildlife populations continue declining at rates, and the threats to biodiversity turn out to be the main cause. Thiamine diphosphate cannot be neglected in this research because it plays an important role in cellular metabolism that can occur in five life-sustaining enzymes (Balk et al.). Three classes of animals are chosen for the investigation, including the representatives of ray-finned fishes, several bivalves, and some birds which are found on 45 stations through 15 regions on the territory of the Northern Hemisphere.
In the article, the hypothesis that thiamine deficiency can be a crucial contributor to the declines of populations in different ecosystems of the Northern Hemisphere has to be supported (Balk et al.). To support the chosen positions and the appropriateness of the work, the authors rely on past investigations developed by Manzetti et al. in terms of which thiamine deficiency was proved as an ultimately lethal concept with several health effects on memory, learning abilities, and other brain functions (821).
It is found that thiamine deficiency can be developed in different ways. All tests and their results can be proved in case thiamine is administrated to an individual without deficiency, and no effects are observed. In general, the article is properly developed, including such sections and introduction with enough background information, a strong and clear hypothesis, results, and discussion with the help of which appropriate conclusions are made.
Biodiversity is an amalgamation of two words – biological and diversity. Therefore, the definition of the term ‘biodiversity’ encompasses a large variety of living organisms coexisting in an ecosystem. Biodiversity ranges from the tiniest microbes to the largest mammal. It also includes several species of bacteria, plants, animals, and humans. The recent study discovered 8.7 million different species worldwide, out of which a normal man recognizes only 1.2 million species.
However, the existing biodiversity is at risk. Both natural and human-activities are contributing to degrading the ecosystem. The changing climate and infestation of alien species are threatening the current biodiversity. Furthermore, in the pursuit of modernization, urbanization, and aggressive ambitions, humans are exploiting the natural habitat. Several factors, such as habitat fragmentation, atmospheric pollution, over-consumption of the natural resources by the humans, etc. are putting additional pressure on the planet.
Over one million species are on the verge of extinction. Humans have altered the environment in the quest to dominate the planet. Thus, the vast wealth of the earth is gradually vanishing. There are such thirty or more spots on the planet where several species are under the threat of extinction. Scientists have termed these regions as biodiversity hotspots. These biodiversity hotspots are home to 60% of different kinds of species.
The need of the hour is to participate in conserving biodiversity. Another word for conservation is caring for the environment. The first step to prevent dwindling biodiversity is to protect the plants and animals in their natural habitat.
It would be possible to create a safe habitat for various species by putting an end to the fragmentation of land for selfish purposes. Several species are sensitive to pollution. For instance, salmons can only thrive in freshwater. The concentration of toxic chemicals in the stream may lead to a declining population of salmons. Furthermore, the burning of fossil fuels gives rise to carbon dioxide emission, which is harmful to some species. A large number of species become homeless as a result of deforestation. Moreover, deforestation also leads to climate change. It harms migrating species.
Native plants and animals survive when they interact with the environment freely. It would be best not to disturb them in their natural habitat. Thus, humans need to take responsibility for their actions, and consciously stop polluting the environment.
The government is preserving biodiversity by restoring the natural habitat and assigning protected areas. Furthermore, an initiative to safeguard the forest-dwelling animals, the government is prohibiting wildlife trading and poaching. The government will take further actions to mainstream biodiversity conservation. The government is working towards capping fisheries, mining, farming, concrete construction in green zone areas, etc. enabling multiple species to interact and interconnect freely.
Biodiversity is an amalgamation of two words – biological and diversity. Therefore, the definition of the term ‘biodiversity’ encompasses a large variety of living organisms coexisting in an ecosystem. Biodiversity ranges from the tiniest microbes to the largest mammal. It also includes several species of bacteria, plants, animals, and humans. The recent study discovered 8.7 million different species worldwide, out of which a normal man recognizes only 1.2 million species.
However, the existing biodiversity is at risk. Both natural and human-activities are contributing to degrading the ecosystem. The changing climate and infestation of alien species are threatening the current biodiversity. Furthermore, in the pursuit of modernization, urbanization, and aggressive ambitions, humans are exploiting the natural habitat. Several factors, such as habitat fragmentation, atmospheric pollution, over-consumption of the natural resources by the humans, etc. are putting additional pressure on the planet.
Over one million species are on the verge of extinction. Humans have altered the environment in the quest to dominate the planet. Thus, the vast wealth of the earth is gradually vanishing. There are such thirty or more spots on the planet where several species are under the threat of extinction. Scientists have termed these regions as biodiversity hotspots. These biodiversity hotspots are home to 60% of different kinds of species.
The need of the hour is to participate in conserving biodiversity. Another word for conservation is caring for the environment. The first step to prevent dwindling biodiversity is to protect the plants and animals in their natural habitat.
It would be possible to create a safe habitat for various species by putting an end to the fragmentation of land for selfish purposes. Several species are sensitive to pollution. For instance, salmons can only thrive in freshwater. The concentration of toxic chemicals in the stream may lead to a declining population of salmons. Furthermore, the burning of fossil fuels gives rise to carbon dioxide emission, which is harmful to some species. A large number of species become homeless as a result of deforestation. Moreover, deforestation also leads to climate change. It harms migrating species.
Native plants and animals survive when they interact with the environment freely. It would be best not to disturb them in their natural habitat. Thus, humans need to take responsibility for their actions, and consciously stop polluting the environment.
The government is preserving biodiversity by restoring the natural habitat and assigning protected areas. Furthermore, an initiative to safeguard the forest-dwelling animals, the government is prohibiting wildlife trading and poaching. The government will take further actions to mainstream biodiversity conservation. The government is working towards capping fisheries, mining, farming, concrete construction in green zone areas, etc. enabling multiple species to interact and interconnect freely.
Biodiversity refers to the sum total of species, ecosystems and genes in a certain location. The term encompasses all spheres of biological systems such as the genetic or molecular sphere, the population sphere, the species, ecosystem and organ spheres, as well. Conversely, an introduced species is one that exists in an area outside of its native region. Usually, humans may bring them into a certain location either intentionally or accidentally.
Sometimes introduced species may turn invasive and thus cause harm to the native population. The question of introduced species’ effects on biodiversity is a complex one as there is no single consequence of these organisms. Consequently, one must analyse both sides of the debate thoroughly before one can assert that introduced species either are harmful to biodiversity.
How introduced species harm biodiversity
Conservationists are deeply concerned about introduced species because they threaten the existence of native species. At times, this may occur through direct interactions with the introduced species or through the dependence of other species on the threatened one. When other species depend on the replaced one, then they may loose their habitat, source of food, or mode of reproduction. Eventually, they may also become extinct or endangered.
The danger posed by introduced species may occur through various pathways: competition, predation or parasitism, disease, hybridisation, modification of the habitat as well as herbivory. When these phenomena manifest, then they eventually lead to the loss of biodiversity. Studies indicate that introduced species come second to habitat destruction with regard to their threat on native biodiversity. Usually, certain barriers exist in natural environments to allow species to evolve on their own.
Few of these barriers include mountains, deserts, rivers and ocean. If these barriers did not exist, then it would be quite easy for species to enter new niches and minimise biodiversity in that area. Human beings have contributed adversely to circumvention of these barriers by bringing species, from other areas, for food or commercial purposes. Introduction of species, therefore, accelerates the amount of time needed to broaden a species’ range (Cohen & Carlton 1998).
The most direct and serious way of reducing biodiversity by introduced species is competition. Non native populations will compete for the same space, nutrients, polluting insects or light as the native ones. In certain circumstances, the introduced species may be better equipped to fight for these resources than the local ones thus outcompeting them. This may lead to the decline of species in such locations.
One scenario was the Australian paperback tree, which invaded the US in Florida. The tree had a spongy bark and flammable leaves that made it better able to utilise resources in its foreign location; this caused adverse competition for numerous native plants. As the Australian paperback kept spreading, more local plants kept reducing. Even other mammals and birds that had adapted to the native plants started declining.
Therefore, competition causes biodiversity loss by eliminating organisms that directly compete with the invasive species, and reducing the ones that depend on the first variety. Other examples of introduced plants that have outcompeted local ones include the Australian Caulerpa, which steeled in the Mediterranean Sea, as well as the South American water hyacinth.
The North American gray squirrel, which came from Italy and Britain, has a better way of getting nuts than local ones. These indigenous squirrels have less access to resources and thus fewer chances of survival (Moritz 1999).
Sometimes introduced species can become predators or parasites on native populations. These organisms may be too strong for the local ones thus perpetuating their extinction. One such instance was the case of the pacific black rat. It was introduced into Hawaii and attacked the eggs of honeycreepers, which were local Hawaiian birds (Johnson 2003).
In fact, several bird species that live in islands have no way of protecting themselves against introduced hunters like the Pacific black rat. The brown tree snake is also a commonly cited example. This species emanated from Admiralty Islands, and was responsible for the eradication of 11 bird types in Guam. The Nile perch has predated upon cichlid fish in East Africa’s Lake Victoria.
Approximately 100 species of these organisms have disappeared as a direct result of the Nile Perch’s predatory activities. An example of how introduced species can become parasites is the case of the Asian chestnut fungus.
This species used American chestnut trees as hosts and eventually led to their elimination from most parts of eastern US. Approximately 180 million acres of land lost this species biodiversity. Additionally, almost a dozen moth species depended on the American chestnut trees, so they also became extinct or endangered.
Certain introduced species can breed with native organisms and alter the gene pool in the species. Hybridisation affects indigenous populations by creating an offspring that is better adapted to its environment than the local one. As such, the introduced species as well as the hybrid displace the local species into extinction because they have a genetic advantage.
This form of invasion occurs over a relatively long period of time thus making them seem less dangerous. Rhymer and Simberloff (1996) explain that the seriousness of the phenomenon may not be very evident from direct observation of the morphological traits of the species. Therefore, the scientists used molecular technology in order to study the extent of hybridisation among various species.
They argued that gene flow occurs naturally in various settings. However, when hybridisation takes place, then more genes are lost, and at a faster rate than in cases where no introduced species exist. Such foreign species threaten rare species particularly because their gene pools are delicate. This is a process called genetic pollution; other experts called it genetic erosion.
When human beings manipulate organisms’ genes for increased yields in agriculture, they eventually, make wild and domestic varieties less common (Wilson 1992). Genetic erosion is a danger to environmental diversity because it minimises the prevalence of rare genotypes. The native Hawaiian duck is adversely affected by introduced species such as mallards because it has bred with them.
Now the duck’s gene pool is bearing more resemblance to the invader; in other words, it has evolved. Another case was hybridisation of the Texas fish with genes from the mosquito fish. Now the Texas fish is regarded as an extinct species whose contribution to biodiversity in the area has been undermined (Naylor et al. 2001). Even the Gula and Apache trout have hybridized with several species in their areas of introduction.
In Europe, the white-headed duck has become an endangered species because of hybridisation with the ruddy duck from North America. The white-headed duck is regarded as one of the rarest ducks in the world, yet the ruddy duck’s continual expansions into Europe ruined this (Eildredge 1998).
Introduced species can modify habitats as well. They often make their new environments unfavourable to indigenous species, which struggle to adapt and eventually die out. One classic case is the zebra mussel; the organism had a way of filtering large quantities of water that led to the reduction of planktons in the water. Additionally, because the zebra mussel spreads so quickly, it became so difficult for indigenous populations to survive in these environments.
Almost thirty species of freshwater species face extinction in areas inhabited by the zebra mussel. The introduction of Prunus spinosa into Western Europe has substantially altered habitats for the Thecla betulae butterfly. The introduced species came from Eastern Europe, and leafs much faster than the local plants. Not only did the Prunus spinosa endanger the local plants, but also modified the indigenous butterfly’s habitat thus threatening its contribution to biodiversity too (Pimentel et al. 1999).
Non native species can also spread diseases that harm indigenous populations. A typical scenario was the introduction of a European parasite that led to the prevalence of whirling disease among rainbow trout in the US, Pennsylvania. They disease spread to other regions of the country and diminished rainbow trout in most parts.
On occasion, introduced species may not be parasitic or predatory; they may be herbivorous. In this regard, these animals will consume native plant species and thus lead to their elimination. Although many individuals rarely think about these particular animals, the goat has been one of the most threatening organisms to native plant species.
When goats came to the Atlantic Island during the 16th century, they ate plenty of local plant species. As a result, 50% of these organisms were lost. Perhaps it is the beneficiary effects of the goats to the human being that make it appear non invasive. However, when one studies this issue from the perspective of the plant species, then one realises that herbivory can indeed be detrimental to biodiversity (Spicer 2006).
How introduced species may not harm biodiversity
Bartomeus et al. (2008) carried out research on the effects of invasive plants on the pollinating patterns of the population. Their results contradicted what most conservationists say about introduced species. The scientists found that it was not just the invading population that benefitted, but the local population, as well. Invasive plants may sometimes increase the number of pollinating agents that visit a particular ecosystem.
The agents under consideration in this research were insects. It was affirmed that, unlike what floral market analysts claim, more insects increased in that population. Since the introduction of foreign plants in the area of study did not occur in a simple manner, then it was necessary to analyse the competition structure of the respective ecosystem. In this analysis, there were two invasive plants: the prickly pear type called Opuntia stricata and the balsam or Carpobrotus affine acinaciformis.
They both have very attractive flowers that attract more insects than the native populations. Furthermore, because those flowers are also rich in pollen, then more pollinating agents can visit them. The prickly pear type received 30.9% visits from insects while the balsam received 43.4%. The researchers concluded that whenever pollinating resources increase in a community of plants, then more insects will visit the area. Approximately 23 pollinating insects visited the Carpobrotus.
Unlike the other invading species, which was an exclusive feeder, this particular insect visited other plant types, including the local ones. Balsma plants can alter reproduction processes in native species because they change reproduction patters in these new areas.
Local plants have a better chance of increasing their population when such species enter their niches. This study indicates that not all invasive species are detrimental to the existence of local populations. Some of them can increase the rate at which indigenous organisms reproduce and exist.
Some introduced species can also fight pollution when the concerned location becomes unfavourable for other organisms; the Asian oyster is one such example. When introduced into water bodies, it was able to filter out more water pollutants than the native oysters. This was quite beneficial because the water quality in Chesapeake Bay, US had deteriorated adversely. The oyster made the water more habitable for other species by minimising pollution.
Even the notorious zebra mussel has some positive effects on water quality. Studies illustrate that water clarity has increase by five or six times in Lake Erie, where the zebra mussel exists. Greater water clarity has emanated from the zebra mussel’s feeding habits; it consumes fertiliser runoff as well as algae. As a result, more light penetrates into the lake thus providing the underground plants with access to ultraviolet rays needed for survival.
Therefore, microphyte beds have returned to the lake in times when they had previously been missing. Part of the reason for their scarcity was the pollution in the lake. The microphyte beds also provide new species of fish with nurseries, which nurture their re-emergence.
In line with the above argument is the issue of modifying environment in favour of local populations. The common gorse came into New Zealand from Scotland. It easily adapted to its environment, and fitted in well with the rest of the population. However, it threatened many native plants through competition. In the long run, after eradicating some native plant species, it started providing nurseries for their reestablishment.
Introduced species may not necessarily lead to the minimisation of biodiversity if other species enter the ecosystems too (Newcomb 2001). In this regard, when local species are destroyed, then other species may come in to fill the void. This interchange of species can sometimes lead to a greater level of biodiversity in some areas than had existed prior to the extinction of certain species.
Nonetheless, the occurrence of this phenomenon has not been explored in as much detail as the reverse phenomenon; that it, extinction of species. In fact some individuals argue that researchers have a tendency to stop at the immediate losses that occur in a certain location. Many of them do not look into the long term implications of invasive species on diversity.
Sometimes a certain population may be burdened by invasive species. Consequently, humans may introduce other species as a means of biological control. Here, introduced species may remedy the effects of other harmful species in the area. One such instance is the use of the South American caterpillar moth to control prickly pear cactus in Australia. The latter species came from the Americas, and invaded numerous Australian lands.
They seriously affected the ability of local plants to grow and thrive in these locations. It was necessary to introduce an enemy to the invasive species in order to restore biodiversity in the area. An example of such an experiment was the alligator weed in the US, which had come from South America.
The weed was a danger to aquatic diversity in the state of Florida owing to its high rate of expansions. Scientists introduced the alligator weed flea beetle to control this population. As a result, the population of the weed radically reduced, and this enhanced biodiversity for other organisms that had been crowded out (Wiedenmann 2000).
Nonetheless, for biological control to work, then the natural enemy of the invasive species needs to have a high degree of specificity. The conservationists must do a thorough research of the exclusivity of the species under consideration (Geerat 1991). If it is a general feeder, then it may become dangerous to the local population.
The cane toad in Australia was one such example; it was introduced in the continent as a method of biological control against the Greyback and French cane beetle. Unfortunately, the parties responsible for it did not know that it would feed on other insects in the area. They did not predict that the cane toad would also threaten other local frogs through competition and disease introduction.
A number of other carnivorous animals also died from the poison in the cane toads’ parotid glands. The population of tiger snakes, crocodiles, quolls and dogs reduced dramatically when they ate this amphibian. A domino effect can occur when a biological agent’s full effect on the ecosystem s not well understood. Another scenario of biological control gone wrong is the Rhinocyllus conicus. This weevil was supposed to minimise the Canadian and Musk thistles.
The latter introduced species had threatened local plant species extensively. The weevil turned on native plants that were an important source of food to local insects. Consequently, not only did the local plants face the threat of extinction, but so did other insects that depended on the thistles. Eventually, this has a negative effect on the biodiversity of the place.
Introduced species can also improve biodiversity in an area when they are brought for conservation purposes. In such scenarios, a species may be in danger of extinction. Therefore, environmentalists may take it upon themselves to introduce those new species to the same locations that they existed before. Although introduction of the invasive species may have caused the problem in the past, it can also contribute to the prevalence of a higher native population of species.
Cases of native restoration include the introduction of the Red Kite in Scotland and England. Wolves were also introduced in Yellowstone National Park within the US after their numbers were reduced dramatically. Additionally, some individuals take it upon themselves to plant trees in their personal properties that match the local population.
Reintroducing endangered species works by expanding the gene pool of threatened animals. Many of these genes may be highly concentrated in one area but not prevalent in another. It thus becomes necessary to translocate them to the depleted gene pool in order to restore their numbers.
In other instances, the elimination of introduced species may be more of a political battle than an environmental one. In this case, it mirrors xenophobia or ethnic hatred. The attitude towards all things foreign is sometimes transplanted in botany or other areas of nature conservation. Well known writers, such as Nellie Doubleday, have reflected these ideologies in their writings about natural landscapes.
He asserted that American plant life needed to reflect the racial temperament of the country. Therefore, styles of gardening inevitably demonstrate this perspective. Another landscaper called Jens Jensen explained that the landscape environment he was creating needed to reflect the racial traits of the US.
They needed to be devoid of non American influences such a Latin or Oriental mixes. He claimed that plant types that borrowed from these influences were ruining the American character. Furthermore, he added that Latin elements were always spoilers (Simberloff 2003).
While such attitudes were quite strong in the early twentieth century, their influences still exist today. Journalists, researchers and other stakeholders appear to be interested in causing mass hysteria regarding introduced species. For instance algae may be described as ‘killer algae’ while rats may be called ‘giants’. All these words create fear in the masses and propel the government to make laws that support xenophobic tendencies (Gobster 2005).
Sometimes the focus is always on the commercial industries and few arguments dwell on indigenous biodiversity. Several stakeholders may assume that all introduced species are harmful unless proven others. Consequently, one can realise that in certain circumstances intolerance to all things foreign determines people’s reaction to invasive species rather than their actual harm
Conclusion
An analysis of the issue illustrates that although introduced species have certain benefits, they appear to cause more harm than good to biodiversity. They cause competition and modify habitats for local species. Additionally, they may become parasitic or predatory on certain organisms. On top of that, some hybridize and cause diseases among indigenous species.
The purported benefits of introduced species are questionable because when used as biological agents, they may turn on other vulnerable organisms. Additionally, those introduced species that fight pollution or modify habitats for the benefit of other organisms, also destroy it for others; the net outcome is negative. Therefore, introduced species may have a lot of commercial value, but their harmful effects on biodiversity are too much to ignore.
References
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Simberloff, D 2003, ‘Confronting introduced species: a form of xenophobia?’, Biological Invasions, vol. 5, pp. 179-192.
One risk that is usually associated with population growth is biodiversity risk. Biodiversity risk can be generally described as business risks linked to biodiversity.
This includes threats that occur as a consequence of direct reliance on biodiversity, in addition to funding, regulatory, reputational and supply chain threats that occur due to business associations with biodiversity. A study by Kevin and John (2004) reveals that loss of biodiversity leads to: coastal flooding, desertification and food insecurity. Let’s look at each of these separately.
Costal Flooding
The elimination of chief coastal ecosystems usually augments the brutality of coastal flooding. Coastal aspects such as vegetated coastal dunes and coral reefs form efficient buffers against natural calamities, tornados, and coastal grinding.
Besides their fundamental role in coastal fortification, these coastal aspects are vital for various marine food chains, including vital nursery regions and homes for commercially costly fish and shellfish organisms. In prospect, with the pervasiveness of greater populations in coastal regions, the economic and human costs of destruction to coastal environment s are expected to rise.
Desertification
Ecosystem deprivation, driven mainly by population increase, industrialization and growth of agriculture has been a chief driver of desertification, ensuing in the widespread thrashing of once prolific land. Growing water shortage, itself partly a consequence of deforestation or elimination of vegetation, is compounding the issue in several areas.
Food Security
The productivity of agricultural systems is greatly dependant on geologically assorted soils and other chief ecosystem services like climatic constancy, water regulation and pollination. A study by Garcia-Torres (2001) reveals that by 2050, these agricultural schemes will be expected to feed an envisaged population of 9 billion. This will lay vast pressure on limited land resources and will relentlessly test the capacity of ecosystems to produce the services that supports agriculture.
Impacts of Biodiversity Risk on Businesses
Loss of biodiversity interrupts businesses in several ways. Some of these ways include: reduced productivity; scarcity and increased costs of resources; restricted access to land and other resources; litigation; reduced quotas; pricing and compensation regimes; reputation risk; financing risk; and supply chain link.
Main industries for example, forestry, farming, fishing and extractives are largely impacted, although no quarter escapes unharmed by some type of biodiversity risk (World Economic Forum, 2010).
A Case Study of Biodiversity Loss and Agricultural Supply Chains
Agricultural yields depends on biodiversity and ecosystem services such as water preserving aspects of the landscape, local and international climatic steadiness and genetic inconsistency of crops. Nevertheless, modern agriculture also necessitates vastly modified ecosystem conditions. Associations amid biodiversity, ecosystems and agricultural activities are multifaceted and dependent on instabilities.
Costs incurred as an effect of these instabilities influence the whole value chain, including producers, processing companies and retailers. Producers are influenced by condensed crop returns; processing companies are influenced by supply disruptions and increased input costs; and retailers are influenced in that they are increasingly required to invest in evaluating supplier and merchandise associated biodiversity risks.
Ways of Preparing for the Risk
Public societies, among other organizations, are providing augmented subsidy for biodiversity preservation in cultivated landscapes, acknowledging the need to work outside confined regions.
Farmers are practicing agricultural practices that offer chances for farmers and agri-businesses to enlarge yields more sustainably. Several initiatives are being subsidized by the food and agriculture businesses to encourage sustainable cultivation.
Tools for Evaluating Biodiversity Risks
Biodiversity risk can be measured by use of various tools including: Ecosystem Services Review (ESR), Natural Value Initiative (NVI) and Integrated Biodiversity Assessment Tool (IBAT). First, ESR contains a series of queries that helps managers build strategies to control risks and openings arising from an organization’s reliance on ecosystems.
Second, NVI contains the Ecosystem Services Benchmark (ESB), a technique for evaluating biodiversity, associated risks and openings in the beverage, food and tobacco quarters. Lastly, IBAT is a testing tool which portrays data from the World Database of Protected Areas (WDPA) and extra sources, aimed at aiding organizations to incorporate biodiversity risks in their managerial and planning procedures.
Managing Biodiversity Risk
There exist practical measures which businesses can use in managing their exposure to biodiversity risk. Among them are evaluating possible risk for the business and communicating your initiatives, performance and success to stakeholders (Leveque and Mounolou, 2003).
Evaluating Possible Biodiversity Risks for your Business
With the aid of exterior organizations and suitable tools, spot your business’s direct effects and dependencies on biodiversity, together with possible material threats. Evaluate your contact with other biodiversity associated risks including: regulatory, physical, company brand and supply chain.
Communicating Initiatives, Performance and Successes to Stakeholders
Employ your progressive ideas and opinions with industry plans to stretch out to other organizations and build strategic coalitions. Make use of early in policy consultations to aid in shaping awaiting national and international ecosystem associated policies and make sure that you are well placed to manage the repercussions. Reflect on leveraging media concern in biodiversity to reinforce your ideas.
The Importance of Biodiversity Risk in Tasmania
Biodiversity risk in Tasmania led to the call for biodiversity conservation among various stakeholders. In June 2009, the Australian minister for environment programmed Tasmanian on the agenda of the Environment Protection and Biodiversity Conservation Act (EPBCA) as a gravely jeopardized ecological society (Tasmanian Conservation Trust, 2011).
Actually, this was a momentous resolution by the minister as we cannot underestimate its significance for biodiversity preservation in Tasmania.
In conclusion, biodiversity risk affects businesses since the loss of biodiversity leads to: coastal flooding, desertification and food insecurity, all of which have impacts on business organizations. The main industries that are impacted by biodiversity risk include: forestry, farming, fishing and extractive industries.
Farmers are practicing sustainable methods of farming as one way of preparing for the biodiversity risk. Several tools can be used to measure the risk. Some of these include: ESR, NVI and IBAT.
There exist practical measures which businesses can use in managing their exposure to biodiversity risk. Among them are: evaluating possible risk for the business and communicating your initiatives, performance and success to stakeholders.
References
Barbier, E. B. (2007) Valuing ecosystem services as productive inputs. Economic Policy, 22 (49), 177-229.
Eliash, J. (2008) Eliash review: climate change. London, Financing Global Forests.
Garcia-Torres, L. (2001) Conservation agriculture in Europe: current status and perspectives. London, Sage.
Kevin, J. G. and John, I. S. (2004) Biodiversity: an introduction. 2nded. New York, Blackwell Publishing.
Leveque, C. and Mounolo, J. (2003) Biodiversity. New York, John Wiley.
Sala, O. E., Meyerson, L. A. and Parmesan, C. (2009) Biodiversity change and human health: from ecosystem services to spread of disease. New York, Island Press.
Tasmania Conservation Trust (2011) Private land biodiversity. Web.
Tor-Bjorn L. (2001) Biodiversity evaluation tools for European forests. New York, Wiley-Blackwell.
World Economic Forum (2011) Global Risks Report 2010. Web.
Worm, B. (2006) Impacts of biodiversity loss on ocean ecosystem services. London, Sage.
For a place to be termed as a hotspot, its degree of endemism should be put into consideration. Mostly, vascular and vertebrate animals are usually prioritized when it comes to endemism. Therefore, hotspots are regions of biodiversity conservation, and the concept of a region qualifying to be called a hotspot has undergone several reviews since its inception. In the latest review which was done in the book, ‘Hotspots: Earth’s Biologically Richest and Most Endangered Terrestrial Eco-regions’ of 1999, regions which had less than 44 percent of the world’s plants and 35 percent of terrestrial vertebrates, were considered hotspots (Biodiversity hotspots, 2008). In total, the latest evaluation discloses a total of 34 Biodiversity hotspots, each supporting more than 1500 Endemic plant species and losing more than 70 percent of its original habitat.
In addition, the number of agencies that focus on the conservation of biodiversity has risen. They include Birdlife International, which identified 218 Endemic Bird Areas (EBA), “each of them holding more than two birds found nowhere else in the world” (Biodiversity hotspots, 2008). The World Wildlife Fund of the United States is also another agency, which came up with a system called the Global 200 Eco-regions for selecting priority Eco-regions. Others include the World Bank, USAID, and Wildlife Conservation Society, which have come together to bolster the effort in biodiversity concern. In the year 2000, the World Bank and the Global Environment Facility joined CI to set up a partnership fund.
Atlantic forest is an example of biodiversity hotspot found in South America, and stretches along Brazil’s Atlantic coast, from the northern state of Rio Grande do Norte south to the Rio Grande do Sul (Biodiversity hotspots, 2008). Its approximate area of coverage is about 1, 233, 875 km2, and has 20,000 plant species, for which 40 percent of it endemic. Currently, 99, 944 km2 remains with the vegetation cover. There are 264 mammals, and 72 of them are endemic. Also, there are 934 birds’ species, and 144 of these are endemic. The species of reptiles total to 311, of which 94 of them are endemic. There are also 456 amphibians, and 282 of these are endemic (Biodiversity hotspots, 2008). Its unique biodiversity is composed of more than 10 percent of endangered vertebrate species, which maintain their survival in this region.
They include; three species of lion tamarins (Leontopithecus spp) and six bird species confined to part of the forest near Murici ecological station in northeastern Brazil, others being extinct like the Alagoas curassow. Human activities are responsible for the destruction of the habitat, and it began in the 16th century when Portuguese, French, and Spanish established their settlements along the Atlantic coast. Forests were destroyed to provide timber and create more room for ranches and sugarcane plantations. The rapid population growth is also a contributing factor to this mass habitat destruction creating room for settlements.
Several mitigation measures have been undertaken to curb this destruction. Strict measures have been put by the Brazilian government. Furthermore, conservation has received a boost in terms of funding, and the process has a large body of well-trained conservation professionals.
Another hotspot region in our focus is the Indo Burma of tropical Asia east of the Ganges Brahmaputra lowlands, and it covers 2, 373, 000 km2 (Biodiversity hotspots, 2008). The remaining vegetation covers about 118, 653 km2 of the total area. In the last twelve years, six large mammal species have been discovered which are not found anywhere else in the world. They include “the large – antlered muntjac, the Annamite muntjac, the grey – shanked douc, the Annamite striped rabbit, the leaf deer and the saola” (Biodiversity hotspots, 2008). The region also boasts with the endangered freshwater turtle species, which are under a threat of extinction due to over-harvesting and destroyed habitat. There are 1, 300 birds’ species, including the “white-eared night-heron, the Grey-crowned crocias, and the orange-necked partridge.” Thirty-five amphibians are deemed to be under threat, and one other species is extinct.
Indo Burma was a place of agriculture since its historical times. The fire was used to clear away and prepare the land for different needs, for example, agriculture. The region has experienced a rising population increase since its early times; thus, more land has been cleared to provide room for settlements. Aquatic ecosystems have also been drained to provide room for rice cultivation, therefore, destroying the habitats. Mangroves have been converted to shrimp aquacultural ponds.
The government has stepped in to conserve 236, 000 km2 (Biodiversity hotspots, 2008). These protected areas were established in 1960. The Royal Forest Department, which was established in 1896, is still working. Funds have been allocated to staffing and infrastructural development in the protected areas.