Invasive species Research paper

10 page paper on invasive species This is what has been written so far. That is all the guidelines. Invasive species (IS) are species of animals, plants, and other microorganisms that are translocated by humans into environments outside their native habitats/ranges. Biological invasions are recognized as a component of global change, as their introduction and establishment outside their natural distribution, cause significant economic and environmental harm to local ecosystems. They are characterized by rapid reproduction and growth, high dispersal ability, and high adaptability to new conditions, thus often outcompeting native organisms in their introduced range, and have been recognized as one of the main causes for biodiversity loss globally (Chinchio et al, 2020). For instance, in the United States, invasive species are the second leading cause (after human population growth and associated activities) of species extinction and endangerment (Crowl, 2012); and the estimated cost of invasive species in the United States alone is over $120 billion annually (Crowl, 2012). Some examples of IS are the south-American coypu Myocastor coypus which are invasive in North America, Europe, and Asia (Chinchio et al, 2020). They cause both environmental and economic impacts by consuming aquatic vegetation and undermining riverbanks (Chinchio et al, 2020). Another well known IS is….. Modern transport facilitates the movement of invasive species farther and faster than ever before. As a result, biological invasions are constantly increasing largely….IS affects biodiversity and economy but also facilitates the emergence of diseases. Invasive species carry disease-causing pathogens and parasites, and disease vectors which pose substantial threats to human, domesticated animal and wildlife populations (Ogden et al., 2018). For example, the yellow fever epidemics in the 19th and 20th centuries in North America was facilitated by the escape of Aedes aegypti from West Africa (Tatem, Hay and Rogers, 2006). Within this paper, through real-case examples from the ecological literature, I’ll focus on cases where pathogens or parasites are invaders. Furthermore, it is imperative to bring awareness to those working in animal fields and in public health to consider the IAS a health threat (Chinchio et al., 2020). My aim is to present an overview of how invasive species affect local disease dynamics directly and indirectly, by either acting pathogen hosts or disrupting the recipient ecosystem structure. Lastly, I aim to provide management and control efforts that can improve our reach by targeting actions towards IAS by increasing involvement of workers in the field with animals and a new invasion epidemiology for public health workers (Chinchio et al., 2020). IAS as sources of new parasites IAS may host pathogens that are absent in the area of release and cause their establishment and subsequent spillover to local species, possibly resulting in an increase of disease risk for humans, domestic animals, and native wildlife. The north-American raccoon Procyon lotor, introduced to Central Europe Baylisascaris procyonis, a nematode causing larva migrans syndromes potentially inducing severe central nervous system disease in humans. Introduction to Europe of north-American crayfish Procambarus clarkii infected with the fungus Aphanomyces astaci caused huge economic losses to fisheries, being the pathogen lethal to native crayfishes. Similarly, squirrelpox virus, introduced to the United Kingdom along with the American eastern gray squirrel Sciurus carolinensis, is significantly contributing to the increased mortality of native red squirrels Sciurus vulgaris. Philornis downsi (Dodge and Aitken), a known dipteran parasite of passerine birds in the Neotropics, was first recorded in the Galapagos Islands in the 1960s [13]. This fly has become invasive, successfully colonizing at least 15 islands in the Galapagos archipelago, bringing serious consequences to the native avian fauna due to the blood-feeding behavior of its ectoparasitic larvae [14–16]. While many studies have been conducted on the fly’s effects on birds e.g., [17,18], studies on its associations with parasites and pathogens have only recently been initiated. Research is now underway to study the microbiota and viruses associated with P. downsi e.g., [19], but to date nothing is known about whether this introduced fly is associated with endoparasites, including trypanosomatids. Trypanosomatids have been reported in over 500 insect species [20]; however, it has been suggested that the number of currently reported insect hosts is just a fraction of the total host species that exist [21]. Infected insect hosts include species in the orders of Diptera, Hymenoptera, Siphonaptera, Hemiptera, and Lepidoptera, among others [22,23]. Trypanosomatids can be transmitted vertically or horizontally between insects [24–28], and are easily transferred via ingestion of infected fecal matter from other insects and other food sources [24,29]. Infections with trypanosomatid parasites in insects have a wide range of pathogenicity and virulence, from unnoticeable effects on their hosts to decreased energy levels, lower fitness, negative immune system effects, and sometimes death [29–34]. On the other hand, insects can act as vectors of trypanosomes that seriously affect the wellbeing of other wildlife (including mammals) or humans [35–38]. Philornis downsi has the potential to be a transporter of trypanosomatids that either traveled with flies from mainland Ecuador or that have adopted this invasive fly as a host since its arrival. In Galapagos, there is one report of an insect trypanosomatid, Strigomonas culicis, found in a single native mosquito Aedes taeniorhynchus [39] and reports of a Trypanosoma species associated with an endemic hawk, Buteo galapagoensis and a mosquito, Culex quinquefasciatus [2,39]. However, given that trypanosomatids are common and widespread throughout the world [40], it is likely that there are additional species in the Galapagos archipelago that have the potential to be picked up by P. downsi. Alternatively, given the broad distribution and host range of many monoxenous trypanosomatid species that infect insects [25,33,41,42], it is highly possible that trypanosomatids were introduced withP. downsi. If this is the case, these could pose a potential risk for the insect fauna in Galapagos. However, while pathogen co-introductions occur over a wide range of parasites and host taxa, some pathogens are lost during the invasion process: for example, there is no evidence for Poxvirus in Italian gray squirrel population. Pathogen loss may be due to the absence of the pathogen in the individuals of the founding populations or to its inability to survive to translocation or establish in the area of release. The outcome depends on several factors related to the IAS (e.g., founding population origin), the pathogens (e.g., host specificity), and the area where the species is released (e.g., environmental conditions, presence, and density of local hosts).. As shown by a study on ectoparasites of introduced birds, factors related to transmission efficiency, such as the number of host introduced and host longevity, are likely to play a major role. IAS as amplifiers of local pathogens An increase of local disease risk may also occur if the introduced IAS is susceptible to, and able to transmit, local pathogens. Pathogens acquired by IAS may be amplified and possibly spill back to humans and local species. A case in point is the Australian brushtail possum, Trichosurus vulpecula, in New Zealand. Invasive possums probably became infected with Mycobacterium bovis, the causal agent of tuberculosis in cattle, from wild deer, after the beginning of commercial deer hunting in 1960. Currently, they are the most important maintenance host for bovine tuberculosis, supporting higher transmission rates compared to local species and, being sympatric with cattle, providing interface for transmission between livestock and forest residents. Another case is represented by invasive raccoon dogs Nyctereutes procyonoides, which may amplify rabies circulation in Eastern Europe or cause its reemergence in currently rabies-free countries. IAS competence for pathogen transmission plays a major role in defining the outcome of pathogen acquisition, and, as the possum–tuberculosis case exemplifies, it is the result of both IAS–pathogen interaction (e.g., IAS susceptibility, period of communicability, and pathogen excretion rate) and IAS behavioral patterns (e.g., habitat, home range extension, and intra- and interspecific contact rates). Based on IAS competence, the acquisition of a local pathogen may even lead to the reduction of disease risk (the so-called dilution effect) or to no consequences at all. For example, in Ireland, the invasive bank vole Myodes glareolus has been found to divert fleas from the native wood mice Apodemus sylvaticus, which is a more competent host for Bartonella spp. However, the identification of the contexts in which a dilution effect may occur is still highly debated in ecology, as it strongly depends on local host species diversity and on the interactions occurring between the species involved in the transmission cycle. Indirect mechanisms by which IAS can disrupt local infection dynamics Introduced species may disrupt local infection dynamics also indirectly, i.e., nonacting as pathogen hosts but through competitive and trophic interactions with native species or modification of local habitats, thus altering the abundance and/or contact rates among local host species, parasite infective stages, or vectors. In southern Florida, the invasive python Python bivittatus caused the decrease of several mammal species, inducing the local mosquito vector of zoonotic Everglades virus to feed almost exclusively on the virus’ main reservoir host, the hispid cotton rat Sigmodon hispidus, potentially leading to an increase in pathogen circulation. An example of habitat alteration is given by the activity of invasive feral pigs Sus scrofa on the island of Hawaii: they create wallows and cavities in tree fern trunks improving habitat suitability for mosquito vectors for avian malaria Plasmodium relictum, one of the main threats to native Hawaiian forest birds’ conservation. Again, IAS indirect effects on local infection dynamics are highly context dependent, and mechanisms presented so far may act in concert, producing unpredictable outcomes. In Scotland and Northern England, for example, the invasive gray squirrel has been found to harbor several local strains of Borrelia burgdorferi. However, in those areas, gray squirrels are also causing the decline of another competent host for B. burgdorferi, the red squirrel, and the effect of these concurring mechanisms on human Lyme disease risk remains unknown.