Late last week, alert employees of the Vermont Marble Power Division of Omya, Inc. spotted an odd looking fish in Otter Creek near their Sutherland Falls plant in Proctor. The employees collected the fish and contacted the Vermont Fish & Wildlife Department. Department fisheries biologist Shawn Good later identified the 15-inch, 2.5-pound fish as a Pacu (Piaractus brachypomus). The Pacu, native to the Amazon and Orinoco river basins of South America, belongs to the Serrasalminae fish family, which also includes the various species of Piranha. Pacu can grow quite large, up to 36 inches or more, even in captivity. Despite their size, they are a popular aquarium fish species, and are widely found in pet shops and private aquaria across the country. "Many aquarium fish like this Pacu are often kept by hobbyists because they are considered exotic and out of the ordinary," explained Good, who chairs the department's Aquatic Nuisance Species Committee. "However, even when kept in larger aquariums, many of these exotic fish species will outgrow their owner's ability to care and maintain them." Unfortunately, when pet fish outgrow their aquarium homes, many misguided owners choose to release them into a nearby waterbody, thinking they are doing their pet a favor by setting them free. "Illegal aquarium releases are a common source of exotic species introductions in the U.S.," said Good. "More than 38 species of unwanted fish and dozens of plants, crayfish, and snails have become established in waters of the U.S. These species not only impact native aquatic ecosystems, but they also affect the economy and recreational activities that rely on these ecosystems. While the environmental and economic consequences for many exotic species are unknown, some infestations have cost millions of dollars for control and management. Eurasian watermilfoil and the northern snakehead fish are just two examples that probably originated from aquarium sources. This incident marks the latest of many discoveries of exotic aquarium fish swimming around in Vermont waters. In 2005, a fisherman caught an Oscar - also a South American fish species from the Amazon region - while bass fishing in Lake Hortonia in Rutland County. That same year, a Middlebury College professor found a tropical catfish in Lake Dunmore, in Addison County. Even the common goldfish has been found living, and unfortunately even thriving, in some Vermont lakes and ponds. "It seems that the general public is largely unaware of the dangers posed by releasing aquarium fish into Vermont's waters," said Good. "I can't stress enough how serious this is". Some aquarium fish, plants and other aquatic animals such as exotic snails can devastate Vermont's natural habitats and severely impact our native aquatic ecosystems if they are released into the wild. They may also introduce dangerous disease organisms that can severely impact native fish and wildlife populations." "In this case, the Pacu that was released into Otter Creek would never have survived the coming cold weather, because it requires a warm climate," Good said. "However, if it had been another species like the northern snakehead, it would be an altogether different situation. There are many species of common aquarium fish that could establish populations in Vermont if they were released, and that could cause immense damage to our native fish populations and ecosystems." Because of this threat, a new regulation was passed in 2009 listing fish species that are prohibited from being imported, sold or possessed in Vermont. The purpose is to protect Vermont's valuable natural resources. The list includes a number of aquarium fish species. For more information on the Prohibited, Restricted, and Unrestricted Fish Species rule, visit the Department's website at http://www.vtfishandwildlife.com and follow the link under Law Enforcement to "Rules and Proposed Rules." "In addition to the new regulation," said Good, "it is illegal to release fish into the public waters of Vermont." The potential penalty for unlawful introduction of fish to Vermont waters is a $500 fine. Rather than releasing unwanted aquarium fish and plants into the wild, there are other, more environmentally sound and legal, approaches, such as give them to another aquarium owner, advertise to give them away or donate them to a public facility, nursing home, or business that has an aquarium or water garden. If these options are not available, you can dispose of the fish by placing it in a container of water and putting it into the freezer. Because cold temperature is a natural anesthetic to tropical fishes, this is considered an acceptable method of euthanasia. New sightings of exotic species should be reported immediately to the Vermont Fish & Wildlife Department at 241-3700, or a local Fish & Wildlife District office. Preferably reports should be accompanied with a photo of the fish. For more information on the dangers and risks of releasing aquarium pets and plants into the wild, visit Habitattitude's website at http://www.habitattitude.net/. __________________
Invasion Nation: Anthropogenic dispersal of pioneering species and their perception as invasive rather than successive or beneficial in the industrial era.
Abstract: Organisms are inherently migratory and seeds, fungi, bacteria and insects have dispersed across continents. Human dispersal and natural dispersal are inherently equal in our ability to distribute other species, however, we degrade ecosystems and have co-evolved with numerous other survivors of our civilization, in places that have been disturbed, some organisms thrived in the face of this adversity and reproduce in higher numbers, more frequently and produce enough stored energy to survive long migrations and extreme conditions. Investigations into the true nature of invasive species reveal political ambitions to maintain chemical industrial infrastructure in farming at all costs and make carcinogenic chemicals somehow seem more benign than organisms that have crosses a political boundary. The study of invasion biology has lost sight of succession, acclimation and other fundamental beliefs in the fluid nature of life on earth, and ecological facts. Invasion Biologists' view a static world where very little contact and migration occurs and ignore many relationships that are beneficial or unaffected by each other's presence. To determine the extent that a local forest had been subdued by non native species, samples along 4 transects were counted and identified. There were no observable effects on native species from grasses or dandelions identified close to paved or dirt roads. Introduction: Humans and countless other migratory species have traveled long distances, and often transported other organisms within their migratory movements as they expand and contract their territory. In evolutionary biology, species recede and advance in pulsing patterns as climatic changes occur. Sometimes this takes place more rapidly than their ability to evolve and adapt to changing circumstances, other times it makes areas that had been hostile and makes them ideal. Birds have migrated thousands of miles annually for millions of years often dispersing organisms. Storm events such as hurricanes and floods have been known to redistribute species thousands of miles, often as seeds and spores, a surviving in both salt and fresh water. Natural dispersal of organisms is found to be frequent and long distance, and receiving biota are resilient and accustomed to such events. Man aided dispersal can in no way be distinguished from natural dispersal (Theodoropolous 2001). As we approach the sixth mass extinction of planet earth, attributed primarily to anthropogenic disturbances, is it logical to label certain highly adaptable species as “invasive”,“noxious or“alien when they may be the best suited for small scale wild harvesting, bioremediation and wildlife habitat in some areas? In a theory that aims to suggest a consistent reason for invasions asserts that a plant community becomes more susceptible to invasion when there is an increase in the amount of an unused resource (Davis et. Al 2000). The use of the term invasive species was first coined by Charles Elton in 1953. Elton was highly influenced by a fellow Oxford student, Alexander Carr Saunders, secretary of the Eugenics Education Society, which promoted the study and practice of selective breeding in humans. Eugenics also suggested pseudo-scientific notions of racial and ethnic superiority and was crucial to Nazi scientists who justified genocide and human experimentation through this scientific discipline. The prejudiced mentality towards living organisms deemed “out of place” migrated into the sub discipline of invasion biology. Terms such as genetic pollution, which are still used today, have the heritage of a hate-based philosophy, and often trigger reactionary emotional responses to romanticized ideals of nature rather than logic or sound scientific reasoning.“the field of invasion ecology has largely dissociated itself from other sub-disciplines of ecology, particularly succession ecology”(Davis et al 2001). The sub disciplines of invasion biology or invasion ecology are controversial within ecology and have far reaching ecological and economic consequences. (Grime, J.P. 2001) Chemical corporations stand to lose billions of dollars if a more relaxed stance is taken towards invasive species, or integrated pest management begins to take favor, governmental and private eradication programs could loose funding and many researchers and field workers could loose their jobs. Monsanto, the maker of Round-up, the most common of all herbicides containing the compound glyphosate, falsified data on at least 2 occasions in scientific laboratories. Monsanto has also been convicted of false advertising in French court, and has created more than 30 superfund sites. In terms of habitat destruction, threats to global biodiversity, soil erosion and water contamination, the three plants that have consumed the largest areas of land are wheat, corn and soya. Although these plants do not often colonize undisturbed habitat, their use as an agricultural commodity, especially when grown in large monocultures that often contain genetically modified organisms (GMO) may pose the greatest threat of any species, displacing more native species than any other organisms. The use of “round-up ready”GMO plants has spurred what scientists call “superweeds”. These are crops that are round up ready (resistant to glyphosate) that have spread from one field to another, and also common weeds like Palmer Amaranth (Amaranthus palmeri), which has selected a glyphosate resistant gene after constant exposure to the substance. While some see invasive species as“the second greatest threat to biodiversity”(Vitousek 1996) others view invasive species as a solemn symbol of succession, resilience and abundance. They symbolize a reminder that nature always finds a way to rebuild it self, literally from the ground up. Seeds, like most organisms, have evolved to survive in the most hash conditions, but are much less likely to succeed outside of their optimal range of preferred soil and climate. After countless generations of breeding and selection, both with and without human intervention, some terrestrial plants have evolved to favor soil and microclimates that has been modified by human use. Feral waste areas are often mistaken for being crowded out by invasive alien species, when in fact, they are the only thing that can survive there at that time, filling the niche of an extinct or ecologically extinct organism. Ecologists coined the term “subsidized species” to describe organisms that respond well to human activity (Klemens 2000). There is research coming out demonstrating the possible benefits of of some introduced species. Although it receives much less funding from herbicide companies than studies that include massive eradication efforts. Beneficial relationships between introduced species and native have often been overlooked and understated. They often provide forage for both native and domesticated animals, including cows, goats, chickens, turkey, ducks, bees, deer, butterflies, birds, and countless others. Invasive species have often been introduced as a ground-cover, to hold in exposed soils and preventing erosion. Many aquatic species such as water hyacinth can remove toxins from human sources of water pollution, and can then be used to make bio fuels and other non-food products. Almost every introduced species in the United States prior to World War II had some kind of use in medical professions or as a food or fodder crop for livestock. When post-war suburbia became an institution, people began to look down upon growing a food garden as backwards and a sign of poverty, and suddenly there was a much larger yards and lawns than people had owned before, so landscape companies and nurseries began importing“exotic”plants as show pieces in their yard to add color, textures and sophistication to their yard. Most of these plants cannot survive in the wild, but there are exceptions that adapt to, and thrive in some local or wide ranging conditions. We can see similar trends in flora that followed the destruction of habitat for rail travel in the United States and how plants adapted to the newly disturbed train track areas. Some species such as Eucalyptus, where planted along the railroads to serve as future railroad ties were later found to be inadequate. Although Eucalyptus serves many functions in native habitats, it may also alter other aspects of nearby native plants, animals and aquifers.
Methods: To determine if terrestrial plants labeled invasive truly reduce biodiversity in undisturbed natural habitats, waste areas or ecotones of two such areas. By making an evaluation of what species and how many are present in each samples of 4 zones establishes an idea of what plants are tolerant of non native species and if areas that contain non natives there is a reduced diversity of native species. If there are invasive species present, they should lower the diversity of the area and occur in an unrivaled abundance, limiting or prohibiting the growth of native species. Using a tape measurer to determine a transect and recording the different species present in 4 locations along 10ft. x 1ft. strip of vegetation progressively distant from a paved road. If a plant is truly invasive and a threat to native species it will have migrated out of disturbed, shoulder areas into areas that contain primarily native species. After identifying the species present, and determining which, if any were labeled invasive species it could determine wether any of the invasive species might prohibit any natives from completing their natural cycles of reproduction. To determine the proper identification of terrestrial plants I employ a typical guide to the the most common and invasive plants of North America.
Results: After identifying and counting all the observable species along transects in 4 zones, there was no evidence indicating that any non-native species had either colonized outside of disturbed areas, crowded out native vegetation or reduced biodiversity on this site. The biodiversity was higher in some areas that contained non native species than areas where only natives were present. The most abundant species in the area were native wild flowers, and all 4 transects were within 100 feet of a paved or dirt road. Although this study is small and produces inconclusive evidence scientifically, it does not fit any theories about invasive species and how they interact with natives in terrestrial habitats. While grasses and dandelions might be a big problem for agriculture and industry, it does not seem to be much of a problem for forests, deer or bees.
The other possible invasive species that was present was grass. It is unknown to me at this time if this species of grass is native or introduced, but I find it safe to assume that it has been in contact, and hybridized with at least one non native grass, so I will give the benefit of the doubt that it is potentially an invasive species. It occurred in limited numbers in the 2 samples closest to the paved road. In most situations except the most fragile ecologies such as deserts oases and small tropical islands where there is a small population of endemic and rare species, it is much more likely that both native and non-native species will learn to cope with each others company, and while species are constantly going extinct for many reasons, invaders will also continue to adapt, evolve and continue to migrate as conditions continue their cycles of fluctuation and succession. When Zebra Mussels (Dreissena polymorpha) invaded Lake Erie it lowered eutrophication levels, which lead to more invertebrate growth, resulting in a 5 time increase in yellow perch catch between 1990 and 1996 (Sagoff 1999). Water Hyacinth (Eichhornia crassipes) and Waterlettuce (Pistia stratiotes) have increased dragonfly species richness in South America by providing perching and refuge sites for them (Steward and Samways, 1998)
Discussion: Although it does not surprise me that an ecosystem by the road side could be resilient from outside invaders, there are always threats lurking from not so far away places. The only a few non native plants were noted, and they were closest to the road, occupying waste soil, and relatively few of them; the dandelion (taxacarum officinale), a plant that has been cultivated and documented by humans as a green and medicinal root for centuries in Asia, the Middle East and Europe, as well as a consistent food source for domesticated animals and dozens of species of wildlife in North America. It is rumored that sailors used dandelions on sea voyages to prevent scurvy, with abundant Vitamin C present in their leaves, and there is evidence they were brought to the New World both accidentally and intentionally on early voyages of explorers and settlers. It has been used in phenology studies to track changing temperatures and their relationships to the flowering time of plants. While many domesticated crops failed to show any difference, wild plants have responded to changing temperatures by flowering earlier in the spring. Dandelion is an excellent candidate for further studies of wider scope in phenology because it is so common. While many rare species such as keystones species continue to be killed intentionally by humans or by our development and consumption habits, a wide range of species have also adapted to tolerate our presence and in some cases, thrive from our impact on the planet, some in captivity, some free to roam and procreate in the wild. While reductions in biodiversity may be taking place, it is unfounded and naive to assume that“invasive species”bear much responsibility towards our loss of diversity when global warming and climate change, over development and consumption. The threat of “invasive species”is more often used as a selling point of chemical pesticides, fungicides and herbicides than by real ecologists. The Chemical Industry thrives on the psychological view of invasive species and many pests in general as scapegoats that creates a culture of fear towards the natural world and promotes the constant expansion of large scale agriculture, mining and development into natural habitats which poses a far greater risk to biodiversity than exotic plants can ever impact any ecosystem.
Literature: Theodoropoulos, D.I., (2003), Invasion Biology: Critique of a Pseudoscience, Blythe, Ca: Avvar McNeely, J., (2001), Land Use and Water Resources Research, Invasive species: a costly catastrophe for native biodiversity, Director, IUCN Biodiversity Programme, Gland, Switzerland Inoue, M.N., Goka, K. (2009), The invasion of alien ants across continents with special reference to Argentine Ants and Red Imported Fire Ants. Biodiversity, 10(2) 67-71. Grime, J.P. (2001), Plant Strategies, Vegetation Processes, and Ecosystem Properties.Chichester:John Wiley & Sons, LTD Johnson, E.A., & Klemens, M.W. (Eds.). (2005), Nature in Fragments: The Legacy of Sprawl, New York: Columbia University Press Colautti, Robert I., MacIsaac, Hugh J. (2004), A neutral terminology to define 'invasive' species" (PDF), Diversity and Distributions 10: 135–141, Hails, Rosie; Timms-Wilson, Tracey, (2007) Genetically modified organisms as invasive species? In: Nentwig, Wolfgang, (ed.) Biological Invasions. Springer, 293-310. (Ecological Studies, 193). Charles S. Elton and the Dissociation of Invasion Ecology from the Rest of Ecology, by Mark A. Davis, Ken Thompson and J. Philip Grime, (2001) Diversity and Distributions, Blackwell Publishing
Charles S. Elton and the dissociation of invasion ecology from the rest of ecology Blackwell Science, Ltd MARK A. DAVIS1,*, KEN THOMPSON2 and J. PHILIP GRIMES, Department of Biology, Macalester College, Saint Paul, MN 55105 USA, 651–696–6102, *Corresponding author, E-mail: email@example.com; 2Department of Animal and Plant Sciences, The Universityof Sheffield S10 2TN, UK
Abstract. Despite several decades of research, the field of invasion ecology has not been very successful in developing reliable generalizations regarding the mechanisms and predictability of invasions. In this essay, we argue that one impedi- ment in the field’s development has been that the field of invasion ecology has largely dissociated itself from other subdisciplines of ecology, par- ticularly succession ecology. Taking an historical approach, we suggest that this dissociation began with Charles S. Elton, the generally acknowledged father of invasion biology. We argue further that, despite periodic calls to end what some have regarded as a spurious distinction between native colonizers and introduced invaders,
INTRODUCTION Species invasions are widely recognized as a serious threat to environments and economies throughout the world (Wilcove et al., 1998; Dukes & Mooney, 1999; Pimental et al., 2000). Unfortun- ately, ecologists have not been able to provide much assistance to land managers because the field of invasion ecology has progressed so slowly. A recent assessment of the field has concluded that it is still largely anecdotal, with few reliable generalizations (Williamson, 1999). We believe that the field’s development has been hampered for decades due to an unfortunate dissociation from other fields of ecology, particularly succession ecology. The dissociation of invasion ecology from succession ecology is apparent from any casual invasion ecology has continued to pursue its own generalizations with limited success. We suggest this dissociation may be exacerbated further by incentives produced by the realities of publishing and securing funding for research and also by the use of electronic search engines to identify related articles. We offer several examples of how invasion ecology has benefited from research on succession and regeneration conducted on native species and conclude that the field of invasion ecology would do well to do more of this type of communica- tion and collaboration among subdisciplines. Key words. Biological invasions, invasion ecology, succession, Charles Elton. examination of the bibliographies of papers from the two fields. Each seldom cites the other. For example, three of the most recent and thorough assessments of invasion ecology are by Lonsdale (1999), Williamson (1999), and Dukes & Mooney (1999). Together the three articles contained 182 citations. Of these citations, 106 included the words ‘alien’, ‘nonindigenous’ and /or some form of the word ‘invasive or invader’. Not one cita- tion includes the words ‘succession’, ‘recovery’, or ‘secondary’. A very different pattern is revealed by a review of the bibliographies of recent succes- sion articles. For example, three recent articles on subalpine forest succession ( Donnegan & Rebertus, 1999), tropical succession (Hughes et al., 1999) and succession following hurricanes, volcanic eruptions and massive forest fires (Turner et al., 1997) contain 202 references combined.