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72-595: The Fairbairn Dam is an earth-filled embankment dam across the Nogoa River , located southwest of Emerald in Central Queensland , Australia. Constructed in 1972 for the primary purpose of irrigation , the impoundment created by the dam serves as one of the major potable water supplies for the region and assists with some flood mitigation . Lake Maraboon with an active capacity of 1,301,000 ML (2.86 × 10 imp gal; 3.44 × 10 US gal)

144-542: A common-pool resource which is rivalrous in nature but non-excludable. Thus, on public grounds, all can enjoy the benefits of fishing so long as fish continue to be stocked. Fish stocking is a practice that dates back hundreds of years. According to biologist Edwin Pister, widespread trout stocking in the United States dates back to the 1800s. For the first hundred years of stocking, the location and number of fish introduced

216-482: A 255-page report on United States fish resources. Congress granted the team $ 15,000 to develop food fish stocks, and non-native fish such as rainbow trout , salmon , striped bass and carp were subsequently introduced successfully into United States lakes and rivers. In the early years, fish were stocked by sports clubs and private citizens. Today, state fish and wildlife agencies along with hatcheries are responsible for distributing fish. And until recently, their goal

288-404: A balanced ecosystem with biological diversity is also extremely important. Many scientists have claimed that because fish that are stocked tend to be apex predators , native species may become prey and have to compete with the oftentimes larger introduced fish for food and habitats. Additionally, the use of aircraft to stock fish in the second half of the 20th century meant pilots often stocked

360-443: A better job of recording exactly what species of fish are stocked at any given location. This began in the 1960s when research suggested the negative impacts of fish stocking on the ecological complexity of other life forms. The Wilderness Act of 1964 also opened the public's eyes to the impact stocking has on other organisms. Thus, fish stocking is now the subject of much debate as there are various costs and benefits associated with

432-436: A central section or core composed of an impermeable material to stop water from seeping through the dam. The core can be of clay, concrete, or asphalt concrete . This type of dam is a good choice for sites with wide valleys. They can be built on hard rock or softer soils. For a rock-fill dam, rock-fill is blasted using explosives to break the rock. Additionally, the rock pieces may need to be crushed into smaller grades to get

504-504: A more "natural" level where herring populations are reduced and zooplankton flourish, thus benefiting the ecosystem as a whole. There are additional benefits to fish stocking. Anglers across the country spend millions of dollars through license fees (which benefit state governments) and fishing equipment such as rods, reels, and lures. Members of fishing societies such as the International Game Fish Association and

576-491: A now-threatened species, has been linked to stocking of non-native species. As a matter of fact, 35 species of fish and amphibians have been negatively affected by stocking practices in California. Scientists have established a direct link between non-native fish stocking and decline of these species: golden trout, Lahontan cutthroat trout , mountain yellow-legged frog , Yosemite toad and Cascades frog are all threatened by

648-474: A policy, for example, that states "where a body of scientific evidence shows that stocking in historically non-salmonid waters adversely affects native biodiversity, such stocking should cease." While many organizations remain focused solely on providing quality fishing opportunities, policies and attitudes are shifting toward resource integrity and protection. In Pennsylvania alone, the PA Fish & Boat Commission

720-412: A private pond, it is important to introduce three prey fish for every predator fish. This ensures that predatory fish have enough nutrition to survive and that prey fish can still reproduce. It is also recommended to stock fathead minnows so that both predator and prey fish have enough to feed on. Introducing fish of similar sizes is another important step to ensure that the population grows together. At

792-525: A reservoir elevation of 209.81 metres (688.4 ft) AHD . Water was recorded at 5.58 metres (18.3 ft) above the spillway. Dam capacities in Australia are frequently compared with the capacity of Sydney Harbour which holds approximately 500,000 megalitres (1.1 × 10 imp gal; 1.3 × 10 US gal). This would make the dam approximately 3 times the storage of Sydney Harbour in normal conditions and 4 times in extreme flood. On 29 December 2019

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864-598: A rock-fill dam is New Melones Dam in California or the Fierza Dam in Albania . A core that is growing in popularity is asphalt concrete . The majority of such dams are built with rock and/or gravel as the primary fill. Almost 100 dams of this design have now been built worldwide since the first such dam was completed in 1962. All asphalt-concrete core dams built so far have an excellent performance record. The type of asphalt used

936-551: A rock-fill dam. The frozen-core dam is a temporary earth dam occasionally used in high latitudes by circulating a coolant through pipes inside the dam to maintain a watertight region of permafrost within it. Tarbela Dam is a large dam on the Indus River in Pakistan , about 50 km (31 mi) northwest of Islamabad . Its height of 485 ft (148 m) above the river bed and 95 sq mi (250 km ) reservoir make it

1008-403: A shell of locally plentiful material with a watertight clay core. Modern zoned-earth embankments employ filter and drain zones to collect and remove seep water and preserve the integrity of the downstream shell zone. An outdated method of zoned earth dam construction used a hydraulic fill to produce a watertight core. Rolled-earth dams may also employ a watertight facing or core in the manner of

1080-614: A variety of water activities. Studies have also examined the economic viability of fish stocking. Hansson, Arrheniusm, and Nellbring of Stockholm University find that simple economic analysis suggests Volga pikeperch stocking can be profitable; based on the capital invested in the stock, the economic yield results in an annual interest rate of 43% (from the viewpoint of anglers). These authors also find that increased populations of stocked fish decreases manpower and equipment costs associated with each catch. They also find that specifically for pikeperch, stocking can restore food web interactions to

1152-532: Is a viscoelastic - plastic material that can adjust to the movements and deformations imposed on the embankment as a whole, and to settlement of the foundation. The flexible properties of the asphalt make such dams especially suited to earthquake regions. For the Moglicë Hydro Power Plant in Albania the Norwegian power company Statkraft built an asphalt-core rock-fill dam. Upon completion in 2018

1224-442: Is a government office or private individual conducting the stocking. In the past century, many areas have banned fish stocking for a variety of reasons. In 1959, for example, Yellowstone National Park fish stocking was banned due to cross-breeding between native and nonnative species that was harming the genetic uniqueness of existing populations. This makes fish populations more susceptible to disease. Today, Yellowstone has adopted

1296-677: Is a popular pastime, with 101.6 million Americans over 16 years old participating in wildlife-related activities such as fishing and hunting. Additionally, a report by the U.S. Department of the Interior recorded an 8% increase in angling participation between 2011 and 2016. In 2017, just over 49 million Americans participated in some form of fishing, of which 11.9 million were youth. Most anglers even fish between four and eleven times per year, with some reporting over 100 trips. Adding fish to public lakes and streams makes fishing more fun, especially for young anglers. Fishing also provides Americans

1368-486: Is at hand, transport is minimized, leading to cost savings during construction. Rock-fill dams are resistant to damage from earthquakes . However, inadequate quality control during construction can lead to poor compaction and sand in the embankment which can lead to liquefaction of the rock-fill during an earthquake. Liquefaction potential can be reduced by keeping susceptible material from being saturated, and by providing adequate compaction during construction. An example of

1440-454: Is important to make sure that no pond or body of water is overstocked. Each has a carrying capacity , meaning that any given body of water can only sustain a certain amount of fish. If this carrying capacity is exceeded, fish will have to compete for food and cover, resulting in damage to all organisms in the water. Different countries and states have their own regulations regarding fish stocking. These regulations also differ depending on if it

1512-449: Is in the spring or fall due to mild temperatures and higher levels of oxygen in the water. To acclimate the fish, place the transportation bag in a shaded part of the water and leave it floating for 15–20 minutes. Before releasing the fish, make sure that larger fish and smaller fish are released at different ends of the pond, giving the prey an opportunity to find shelter. Studies show that releasing small numbers of fish at regular intervals

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1584-412: Is more effective than releasing all at once, so if possible, plan to release them over a few weeks. It is also important to stock the correct species of fish. For warm water ponds, it is recommended to stock largemouth bass , bluegill , crappie , channel catfish , and bullheads . For larger and deeper lakes, stocking cool water game fish such as walleye and trout species is recommended. Lastly, it

1656-460: Is not entirely monitored by the Federal government; most current federal regulations hand authority for fish stocking to the states, except on federal lands or when "direct involvement of federal wilderness" managers is necessary for decision making. Historically, there has been a jurisdictional debate between state and federal agencies, with states arguing that fish stocking is a prerogative supported by

1728-480: Is running low in a given body of water, fish are transported from hatcheries in a large water tank or airplane to their respective locations. The costs associated with stocking are typically covered by angler associations, commercial fishermen, state fish and game agencies, and at times government subsidies; today, most stocking is conducted by state fish and game departments. Radinger et al., 2023 conducted large-scale experiments across 20 lakes, to systematically test

1800-456: Is scheduled to stock 4,398,227 trout (brook, brown, and rainbows) into its streams and lakes in 2019. Also in 2019, Lake Ontario , one of the five Great Lakes , is projected to receive 2,767,660 stocked salmon and trout. According to data by state agencies, in 2004 roughly 1.7 billion fish were stocked across the United States. With 104 different species of fish stocked, a total of 43.65 million pounds of fish were released, primarily in

1872-405: Is the practice of releasing fish that are artificially raised in a hatchery into a natural body of water (river, lake, or ocean), to supplement existing wild populations or to create a new population where previously none exists. Stocking may be done for the benefit of commercial , recreational or tribal heritage fishing , but may also be done for ecological conservation to restore or increase

1944-453: Is used to restore native species to waters where they have been overfished or can no longer breed. "Give and take" stocking practices are those where fish are stocked only to be fished and then restocked. In response, most states have adopted regulations that prohibit fish stocking in areas that may damage aquatic life or ecosystem diversity, and encourage stocking in bodies of water where no harm will result from doing so. Trout Unlimited has

2016-573: The Bass Anglers Sportsman Society also enjoy fishing in more robust bodies of water. Despite the findings mentioned above, Virginia researchers have found that even with stockings of rainbow trout, 80% of fish in its stocked streams are still natives. The Department of Natural Resources in Minnesota also found that stocked muskie can coexist because biologically-based guidelines are used when choosing what and where to stock. Until recently,

2088-516: The California Gold Rush in the 1860s when miners constructed rock-fill timber-face dams for sluice operations . The timber was later replaced by concrete as the design was applied to irrigation and power schemes. As CFRD designs grew in height during the 1960s, the fill was compacted and the slab's horizontal and vertical joints were replaced with improved vertical joints. In the last few decades, design has become popular. The tallest CFRD in

2160-827: The Ecological Society of America , when gulls in the Great Lakes area were examined after fish stocking, they consumed more garbage, presumably due to the decrease in native prey fish by the predatory stocked fish. Another study found that stocked fish in the Pacific Northwest spread a disease that caused a 15% increase in amphibian embryo mortality. In 2005, the Center for Biological Diversity studied bodies of water across California and found that non-native trout had been stocked in at least 47 areas where rare species were present, damaging 39 imperiled fish and amphibians. Members of

2232-468: The Usoi landslide dam leaks 35-80 cubic meters per second. Sufficiently fast seepage can dislodge a dam's component particles, which results in faster seepage, which turns into a runaway feedback loop that can destroy the dam in a piping-type failure. Seepage monitoring is therefore an essential safety consideration. gn and Construction in the U.S. Bureau of Reclamation Fish stocking Fish stocking

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2304-444: The "catch-and-release method" to ensure that fishermen release fish back into the water after catching them. There are also restrictions on what types of lures can be used; for example, some sections of the park are open to fly fishing only, a much safer form of fishing that does not damage aquatic life. There is a Native Trout Conservation Area where regulations are structured so that fishermen can selectively remove nonnative fish from

2376-572: The 10th Amendment to the Constitution. Interestingly, the roots of wildlife ownership are grounded in feudal Europe where fish were considered to be common property to all citizens, subject to government control. However, this control over wildlife was transferred to the states with the separation of the Colonies from Britain. Despite the federal government's right to exercise wildlife authority, current regulation states that "Congress has, in fact, reaffirmed

2448-539: The 320 m long, 150 m high and 460 m wide dam is anticipated to be the world's highest of its kind. A concrete-face rock-fill dam (CFRD) is a rock-fill dam with concrete slabs on its upstream face. This design provides the concrete slab as an impervious wall to prevent leakage and also a structure without concern for uplift pressure. In addition, the CFRD design is flexible for topography, faster to construct and less costly than earth-fill dams. The CFRD concept originated during

2520-567: The California Department of Fish and Game agreed to eliminate the environmental harm of its stocking practices, but when it filed its impact report in 2011, protection of native fish and amphibians was clearly not a priority. The agency was brought to court again but was promptly denied. With the state Commission denying the Department of Fish and Game's proposed changes for fish stocking, private hatcheries continue to stock state waters under

2592-881: The Fairbairn Dam was at 9.6% capacity, the previous record low capacity was in December 2006 at 11.8%. In December 2019 the Central Highlands Regional Council made the decision to stay on level 1 water restrictions whilst they were undertaking a review of their trigger levels for water restrictions. A record low of 7.39% was reached in 2020. In late 2022, the dam reached 40% of capacity, allowing farmers to access full water allocations. The lake has been stocked with barramundi , Mary River cod , southern saratoga , bass and silver perch . Eel-tailed catfish , spangled perch , red claw crayfish , sooty grunter and golden perch Georgia fish are additionally present. On

2664-486: The US, grossing $ 720 million that year. Many species of fish including grass carp and the suckermouth catfish help clean bodies of water by eating algae and other green organisms. Algae can take over stagnant ponds, attracting insects and making lakes, rivers, and ponds unpleasant to look at. To treat them, many individuals will choose to stock certain species of fish. This creates a positive externality for those who enjoy

2736-455: The Western states. In the US, common species that are currently stocked for sport include trout , bass , salmon , muskellunge , walleye , and several species of panfish . Before being released into rivers, lakes, ponds, and occasionally oceans across the country, fish are raised in a fish hatchery . Just like humans have a demand for groceries, anglers have a demand for fish. When the supply

2808-595: The Wilderness Research Institute claim that fish stocking compromises the "naturalness" of aquatic ecosystems and that protecting water quality is more important than recreational opportunities. Although stocking programs were designed to boost conservation, in some cases they have harmed them. The increased boat traffic associated with better fishing opportunities creates negative externalities. These include water contamination, congestion, noise pollution, and disruption of wilderness experiences. When stocking

2880-404: The base of the dam than at shallower water levels. Thus the stress level of the dam must be calculated in advance of building to ensure that its break level threshold is not exceeded. Overtopping or overflow of an embankment dam beyond its spillway capacity will cause its eventual failure . The erosion of the dam's material by overtopping runoff will remove masses of material whose weight holds

2952-585: The basic responsibility and authority of the States to manage fish and resident wildlife." In the future, if more differences in opinion between state and federal managers arise, there may be a need for increased cooperation and coordination between state and federal wilderness managers. Colorado, for example, has regulations to control the stocking of nonnative fish, but only below 6,500 feet. To find out more about each state's fish stocking regulations, visit their respective Department of Fish and Wildlife websites. Today,

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3024-450: The cost of producing or bringing in concrete would be prohibitive. Rock -fill dams are embankments of compacted free-draining granular earth with an impervious zone. The earth used often contains a high percentage of large particles, hence the term "rock-fill". The impervious zone may be on the upstream face and made of masonry , concrete , plastic membrane, steel sheet piles, timber or other material. The impervious zone may also be inside

3096-599: The dam filled and overflowed for the first time two years later. The dam wall consists of a 5,249 thousand cubic metres (185.4 × 10 ^  cu ft) earthfill embankment 823 metres (2,700 ft) in length and 46 metres (151 ft) high. The reservoir has a catchment area of 16,320 square kilometres (6,300 sq mi) with an uncontrolled concrete spillway capable of discharging 15,580 cubic metres per second (550,000 cu ft/s). The reservoir has an active capacity of 1,301,000 ML (2.86 × 10 imp gal; 3.44 × 10 US gal) of water; When

3168-435: The dam for irrigation had their water allocation cut by 75%. In November 2006, the dam had reached its lowest level ever—just 14% of total capacity. Over that summer low inflows and high evaporation rates had dropped levels to 12%. On 18 January 2008 water in the reservoir overflowed the dam spillway for the first time in 17 years, due to heavy local rain. Within 48 hours, the water level was about 3.5 metres (11 ft) over

3240-434: The dam in place and against the hydraulic forces acting to move the dam. Even a small sustained overtopping flow can remove thousands of tons of overburden soil from the mass of the dam within hours. The removal of this mass unbalances the forces that stabilize the dam against its reservoir as the mass of water still impounded behind the dam presses against the lightened mass of the embankment, made lighter by surface erosion. As

3312-544: The dam spills over it flows into the Nogoa River. About 300 irrigators are supplied with water for cotton, citrus and other horticulture operations. The dam is relatively shallow with large areas of standing timber. There are no boating restrictions and one concrete boat ramp . Water from the Fairbairn Dam is released down the Nogoa River to the Selma Weir for supply to the town of Emerald. Supplies are diverted by pipelines to

3384-417: The early 21st century. These techniques include concrete overtopping protection systems, timber cribs , sheet-piles , riprap and gabions , Reinforced Earth , minimum energy loss weirs , embankment overflow stepped spillways , and precast concrete block protection systems. All dams are prone to seepage underneath the dam, but embankment dams are prone to seepage through the dam as well; for example,

3456-550: The ecology of lakes and rivers was not well understood. To maximize the benefits of stocking and control the costs, fish must be stocked strategically in places where they can be enjoyed but do not pose a threat to native species. Although there are many benefits of stocking, some groups, including the Pacific Rivers Council , believe that it diverts money away from more effective conservation and protection efforts. In addition, declining populations of native golden trout ,

3528-469: The effects of stocking fish compared to habitat-based interventions (i.e. creating shallow zones and adding coarse woody habitats). Over a period of six years, they closely monitored the fish population response in each lake. The study revealed that species-focused fish stocking was completely unsuccessful and demonstrated the potential for ecosystem-based management to better meet conservation goals. Stocking fish provides various benefits to society. Fishing

3600-420: The embankment, in which case it is referred to as a "core". In the instances where clay is used as the impervious material, the dam is referred to as a "composite" dam. To prevent internal erosion of clay into the rock fill due to seepage forces, the core is separated using a filter. Filters are specifically graded soil designed to prevent the migration of fine grain soil particles. When suitable building material

3672-485: The flow of the water and continue to fracture into smaller and smaller sections of earth or rock until they disintegrate into a thick suspension of earth, rocks and water. Therefore, safety requirements for the spillway are high, and require it to be capable of containing a maximum flood stage. It is common for its specifications to be written such that it can contain at least a one-hundred-year flood. A number of embankment dam overtopping protection systems were developed in

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3744-407: The lake fishing is banned within 200 metres (660 ft) of the dam wall, while below the ban extends for 400 metres (1,300 ft). Embankment dam Embankment dams come in two types: the earth-filled dam (also called an earthen dam or terrain dam ) made of compacted earth, and the rock-filled dam . A cross-section of an embankment dam shows a shape like a bank, or hill. Most have

3816-448: The largest earth-filled dam in the world. The principal element of the project is an embankment 9,000 feet (2,700 m) long with a maximum height of 465 feet (142 m). The dam used approximately 200 million cubic yards (152.8 million cu. meters) of fill, which makes it one of the largest man-made structures in the world. Because earthen dams can be constructed from local materials, they can be cost-effective in regions where

3888-423: The mass of the dam erodes, the force exerted by the reservoir begins to move the entire structure. The embankment, having almost no elastic strength, would begin to break into separate pieces, allowing the impounded reservoir water to flow between them, eroding and removing even more material as it passes through. In the final stages of failure, the remaining pieces of the embankment would offer almost no resistance to

3960-482: The number of endangered or extirpated species. Many of the fish commonly used for stocking also have low reproductive rates and tend to be overfished if not stocked annually. Moreover, as stocked fish tend to contain larger trophy fish, many anglers are more willing to pay for a fishing license , meaning state fishing departments have more revenue to spend on natural resource management and conservation efforts. In 2018, there were roughly 30 million paid license holders in

4032-496: The opportunity to enjoy nature in solitude and escape from their busy lives. It is a form of exercise and a great way to bond with friends and family; fishing has also been linked to increased patience among children. According to a survey by the Outdoor Foundation, 60.3% of fishermen report fishing as a means of getting exercise, 59.1% report fishing to bond with family, and 51.2% report fishing to be close to nature and observe

4104-442: The opportunity to fish in stocked lakes and ponds in the future. Each state has its own regulations regarding fish stocking. Though some state stocking programs restore native populations, others compromise the ecological values of the wilderness areas. The Bureau of Land Management regulates that fishless waters may only be stocked after considering the scientific value of the waters on a case-by-case basis. Fish stocking, however,

4176-451: The population of threatened / endangered fish species that is pressured by prior overfishing , habitat destruction , and/or competition from invasive species . Fish stocking may be conducted by governmental fisheries management agencies, non-profit organizations, and voluntary associations in public waters, or by for-profit NGOs, clubs and commercial enterprises in privately owned waters. When in public waters, fish stocking creates

4248-662: The practice. In the United States, stocking non-native fish for sport and food was just beginning in 1871 when the US Fish Commission was established. The head of the new agency, Spencer Fullerton Baird , was tasked to research "the decrease of the food fishes of the seacoasts and the lakes of the United States and to suggest remedial measures". Baird made his headquarters at Woods Hole on Cape Cod , Massachusetts . There, his team of scientists and researchers conducted studies on striped bass , blue fish and many other commercial and sport fish. They compiled their research into

4320-410: The right range of size for use in an embankment dam. Earth-fill dams, also called earthen dams, rolled-earth dams or earth dams, are constructed as a simple embankment of well-compacted earth. A homogeneous rolled-earth dam is entirely constructed of one type of material but may contain a drain layer to collect seep water. A zoned-earth dam has distinct parts or zones of dissimilar material, typically

4392-680: The same permit regulations. The Department aimed to require that all hatcheries and fisheries pay for biological assessment before stocking, thus preventing many of its negative consequences. However, the state of California made it clear that it will not make fisheries go through the stringent permitting process. In February of 2015, the California Third District of Appeals struck down the Department of Fish and Wildlife's permitting requirement on recreational fishing, which would have essentially driven fish farms and hatcheries out of business. This ruling ensures fishermen in California will have

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4464-470: The same time, make sure that the existing fish in the pond are not significantly larger than the ones being added. For a standard one-quarter acre pond, it is recommended to stock 120 sunfish, 60 yellow perch, 15 largemouth bass, and 8 pounds of fathead minnows. One way to determine what kinds of fish are already living in a given body of water is to monitor local streams, rivers, and lakes and record what species of fish are being caught. The best time to stock

4536-523: The scenery. Some of the fish caught are also large, providing a source of nutrition to successful fishermen. Roughly 40% of fishermen eat the fish they catch, according to a survey by the Outdoor Foundation. Stocking can also restore threatened, endangered, or native fish species. The Union for Conservation of Nature's red list of endangered species has 1,414 species of fish that are at risk of extinction. Stocking them into lakes, rivers, and streams can support existing populations that are threatened and reduce

4608-469: The spillway level, or 156% of active capacity. The water level peaked at about 4.5 metres (15 ft) on 22 January 2008. Downstream 2,700 residents had to be evacuated due to flooding. Seven days earlier, the lake was operating at 29% of full capacity. On 30 December 2010 during the 2010–11 Queensland floods , the Fairbairn Dam reached a peak of 2,289,129 ML (5.03538 × 10 imp gal; 6.04724 × 10 US gal), or 176% of active capacity, with

4680-465: The stocking practice. Mating between native and introduced fish species can lower the fitness of natural populations, thereby introducing diseases that affect fish and other wildlife. In fact, a study conducted in Virginian streams found that an infectious virus was found only in brook trout populations that had a history of stocking. These diseases may affect humans who consume them as well. Maintaining

4752-455: The towns of Blackwater , Bluff , Tieri , Dysart and Middlemount . Water from the dam also supplies coal mining developments on the Bowen Basin . The dam and reservoir are operated by SunWater . A 50th birthday celebration for the dam is being held on Saturday 21 May 2022 sponsored by Sunwater and the Central Highlands Regional Council. In July 2003, cotton farmers who were reliant on

4824-582: The water without damaging native fishery. In 2005, California's Center for Biological Diversity submitted a petition to the Department of Fish and Game requesting that the state initiate a review of its fish stocking practices. The reform campaign aimed to protect existing habitats and native populations of fish and amphibians. Finally, in 2008, the Sacramento Superior Court ordered the state to consult with various groups in finding ways to protect native species from fish stocking practices. Initially,

4896-500: The world is the 233 m-tall (764 ft) Shuibuya Dam in China , completed in 2008. The building of a dam and the filling of the reservoir behind it places a new weight on the floor and sides of a valley. The stress of the water increases linearly with its depth. Water also pushes against the upstream face of the dam, a nonrigid structure that under stress behaves semiplastically, and causes greater need for adjustment (flexibility) near

4968-501: The wrong lakes or rivers. In many cases, this had disastrous consequences. When fish, specifically trout , are stocked into ecologically sensitive bodies of water, invertebrate populations and amphibians are threatened, altering the natural selection pressures within the ecosystem. Stocked rainbow trout have been outcompeting native brook trout in many southeastern United States bodies of water, for example. Even bird populations such as cormorants are affected. According to findings by

5040-547: Was formed by damming of the Nogoa River , and, in 2008, was Queensland's second largest dam. Its capacity is approximately three times larger than Sydney Harbour . Maraboon is the Aboriginal for "where the black ducks fly". Commenced in 1968, the dam was engineered by Snowy Mountains Hydro-Electric Authority and completed in December 1972 for the purposes of irrigation and water storage. Storage of water commenced in January 1972 and

5112-468: Was not well recorded; the singular goal of stocking was to enhance sport fishing regardless of ecological ramifications such as erosion of biodiversity . As Pister states, "When trout planting was first implemented, the nation was gripped with a highly utilitarian resource management ethic that placed short-term human interests above virtually any other consideration". Recently, the U.S. Fish and Wildlife Service along with state fishery branches have done

5184-416: Was to plant as many fish as possible into as many bodies of water as possible. Now, with knowledge of the detrimental effects fish stocking has on invertebrate and amphibian populations, it is conducted much more selectively. Today, much more thought is put into introducing non-native species as they can severely damage the populations of fragile natives; practices lean more towards sustainability. Stocking

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