The walleye called the yellow pike, is a freshwater perciform fish native to most of Canada and to the Northern United States. It is a North American close relative of the European zander known as the pikeperch; the walleye is sometimes called the yellow walleye to distinguish it from the blue walleye, a subspecies, once found in the southern Ontario and Quebec regions, but is now presumed extinct. However, recent genetic analysis of a preserved'blue walleye' sample suggests that the blue and yellow walleye were phenotypes within the same species and do not merit separate taxonomic classification. In parts of its range in English-speaking Canada, the walleye is known as a pickerel, though the fish is not related to the true pickerels, which are a member of the family Esocidae. Walleyes show a fair amount of variation across watersheds. In general, fish within a watershed are quite similar and are genetically distinct from those of nearby watersheds; the species has been artificially propagated for over a century and has been planted on top of existing populations or introduced into waters devoid of the species, sometimes reducing the overall genetic distinctiveness of populations.
The common name, "walleye", comes from the fact that the fish's eyes point outward, as if looking at the walls. This externally facing orientation of the eyes gives anglers an advantage in the dark because a certain eyeshine is given off by the eye of the walleye in the dark, similar to that of lions and other nocturnal animals; this "eyeshine" is the result of a light-gathering layer in the eyes called the tapetum lucidum, which allows the fish to see well in low-light conditions. In fact, many anglers look for walleyes at night; the fish's eyes allow them to see well in turbid waters, which gives them an advantage over their prey. Thus, walleye anglers look for locations where a good "walleye chop" occurs; this excellent vision allows the fish to populate the deeper regions in a lake, they can be found in deeper water during the warmest part of the summer and at night. Walleyes are olive and gold in color; the dorsal side of a walleye is olive. The olive/gold pattern is broken up by five darker saddles.
The color shades to white on the belly. The mouth of a walleye is armed with many sharp teeth; the first dorsal and anal fins are spinous. Walleyes are distinguished from their close relative the sauger by the white coloration on the lower lobe of the caudal fin, absent on the sauger. In addition, the two dorsals and the caudal fin of the sauger are marked with distinctive rows of black dots which are absent from or indistinct on the same fins of walleyes. Walleyes grow to about 80 cm in length, weigh up to about 9 kg; the maximum recorded size for the fish is 13 kilograms in weight. The rate depends on where in their range they occur, with southern populations growing faster and larger. In general, females grow larger than males. Walleyes may live for decades. In fished populations, few walleye older than five or six years of age are encountered. In North America, where they are prized, their typical size when caught is on the order of 30 to 50 cm below their potential size; as walleye grow longer, they increase in weight.
The relationship between total length and total weight for nearly all species of fish can be expressed by an equation of the form W = c L b Invariably, b is close to 3.0 for all species, c is a constant that varies among species. For walleye, b = 3.180 and c = 0.000228 or b = 3.180 and c = 0.000005337. This relationship suggests a 50 cm walleye will weigh about 1.5 kg, while a 60 cm walleye will weigh about 2.5 kg. In most of the species' range, male walleyes mature sexually between four years of age. Females mature about a year later. Adults migrate to tributary streams in late winter or early spring to lay eggs over gravel and rock, although open-water reef or shoal-spawning strains are seen, as well; some populations are known to spawn on vegetation. Spawning occurs at water temperatures of 6 to 10 °C. A large female can lay up to 500,000 eggs, no care is given by the parents to the eggs or fry; the eggs are adhesive and fall into spaces between rocks. The incubation period for the embryos is temperature-dependent, but lasts from 12 to 30 days.
After hatching, the free-swimming embryos spend about a week absorbing a small amount of yolk. Once the yolk has been absorbed, the young walleyes begin to feed on invertebrates, such as fly larvæ and zooplankton. After 40 to 60 days, juvenile walleyes become piscivorous. Thenceforth, both juvenile and adult walleyes eat fish exclusively yellow perch or ciscoes, moving onto bars and shoals at night to feed. Walleye feed on crayfish and leeches; the walleye is considered to be a quite palatable freshwater fish, is fished recreationally and commercially for food. Because of its nocturnal feeding habits, it is most caught at night using live minnows or lures that mimic small fish. In Wisconsin, the walleye is fished for in the late afternoon o
The Mississippi River is the second-longest river and chief river of the second-largest drainage system on the North American continent, second only to the Hudson Bay drainage system. Its source is Lake Itasca in northern Minnesota and it flows south for 2,320 miles to the Mississippi River Delta in the Gulf of Mexico. With its many tributaries, the Mississippi's watershed drains all or parts of 32 U. S. two Canadian provinces between the Rocky and Appalachian mountains. The main stem is within the United States; the Mississippi ranks as the fifteenth-largest river by discharge in the world. The river either borders or passes through the states of Minnesota, Iowa, Missouri, Tennessee, Arkansas and Louisiana. Native Americans have lived along its tributaries for thousands of years. Most were hunter-gatherers, but some, such as the Mound Builders, formed prolific agricultural societies; the arrival of Europeans in the 16th century changed the native way of life as first explorers settlers, ventured into the basin in increasing numbers.
The river served first as a barrier, forming borders for New Spain, New France, the early United States, as a vital transportation artery and communications link. In the 19th century, during the height of the ideology of manifest destiny, the Mississippi and several western tributaries, most notably the Missouri, formed pathways for the western expansion of the United States. Formed from thick layers of the river's silt deposits, the Mississippi embayment is one of the most fertile regions of the United States. During the American Civil War, the Mississippi's capture by Union forces marked a turning point towards victory, due to the river's strategic importance to the Confederate war effort; because of substantial growth of cities and the larger ships and barges that replaced steamboats, the first decades of the 20th century saw the construction of massive engineering works such as levees and dams built in combination. A major focus of this work has been to prevent the lower Mississippi from shifting into the channel of the Atchafalaya River and bypassing New Orleans.
Since the 20th century, the Mississippi River has experienced major pollution and environmental problems – most notably elevated nutrient and chemical levels from agricultural runoff, the primary contributor to the Gulf of Mexico dead zone. The word Mississippi itself comes from Misi zipi, the French rendering of the Anishinaabe name for the river, Misi-ziibi. In the 18th century, the river was the primary western boundary of the young United States, since the country's expansion westward, the Mississippi River has been considered a convenient if approximate dividing line between the Eastern and Midwestern United States, the Western United States; this is exemplified by the Gateway Arch in St. Louis and the phrase "Trans-Mississippi" as used in the name of the Trans-Mississippi Exposition, it is common to qualify a regionally superlative landmark in relation to it, such as "the highest peak east of the Mississippi" or "the oldest city west of the Mississippi". The FCC uses it as the dividing line for broadcast call-signs, which begin with W to the east and K to the west, mixing together in media markets along the river.
The Mississippi River can be divided into three sections: the Upper Mississippi, the river from its headwaters to the confluence with the Missouri River. The Upper Mississippi runs from its headwaters to its confluence with the Missouri River at St. Louis, Missouri, it is divided into two sections: The headwaters, 493 miles from the source to Saint Anthony Falls in Minneapolis, Minnesota. The source of the Upper Mississippi branch is traditionally accepted as Lake Itasca, 1,475 feet above sea level in Itasca State Park in Clearwater County, Minnesota; the name "Itasca" was chosen to designate the "true head" of the Mississippi River as a combination of the last four letters of the Latin word for truth and the first two letters of the Latin word for head. However, the lake is in turn fed by a number of smaller streams. From its origin at Lake Itasca to St. Louis, the waterway's flow is moderated by 43 dams. Fourteen of these dams are located above Minneapolis in the headwaters region and serve multiple purposes, including power generation and recreation.
The remaining 29 dams, beginning in downtown Minneapolis, all contain locks and were constructed to improve commercial navigation of the upper river. Taken as a whole, these 43 dams shape the geography and influence the ecology of the upper river. Beginning just below Saint Paul and continuing throughout the upper and lower river, the Mississippi is further controlled by thousands of wing dikes that moderate the river's flow in order to maintain an open navigation channel and prevent the river from eroding its banks; the head of navigation on the Mississippi is the Coon Rapids Dam in Minnesota. Before it was built in 1913, steamboats could go upstream as far as Saint Cloud, depending on river conditions; the uppermost lock and dam on the Upper Mississippi River is the Upper St. Anthony Falls Lock an
The Rum River is a slow, meandering channel that connects Minnesota's Mille Lacs Lake with the Mississippi River. It runs for 151 miles through the communities of Onamia, Princeton, Isanti, St. Francis before ending at the Twin Cities suburb of Anoka 20 miles northwest of downtown Minneapolis, it is one of the six protected Scenic rivers in Minnesota. The early explorer Louis Hennepin is credited with being the first European to lay eyes upon the Rum, he was taken to see it during the spring of 1680. He referred to it as the St. Francis river in his published journals, although the name didn't stick; the current river bearing the name St. Francis River, located 12 miles west of the Rum, parallels the flow of the Rum; the Rum River makes a sharp turn southward at Minnesota. During the spring floods, the Rum River forces itself through a wetland complex west of Cambridge as the sharp bend constricts the river's floodwaters. In the 1825 First Treaty of Prairie du Chien, the outlet of this natural diversion channel located near Isanti, known as "Choking Creek", became a treaty boundary separating the Dakota from the Ojibwe.
In Princeton, the Rum divides between the Main Branch and the West Branch. When Mille Lacs County, Minnesota was created from Benton County, the West Branch of the Rum served as the counties' boundary. Today, Mille Lacs County's western boundary instead follows the public land survey line; the Bogus Brook, which flows into the Rum River, was known to have been a refuge for moonshiners during Prohibition. The Dakota name for the river is Watpa waḳaŋ, after Mille Lacs Lake. In 1702, d'Isle's map recorded the name of the river as Riviere des Mendeoüacanton. On the "Carte représentant le Messisipi entre le 49e d. et le 42e d. ou aboutit la rivière Wisconsing lac Supérieure, lac des Illinois et lac Alemepigon" map, Rum River is recorded as Rivière de S. François ou des Nadouessioux. On the 1733 Henry Popple map, the Rum River is shown as R. Nendivaocanton. Upham notes that both Carver in 1766 and Pike in 1805 found the name "Rum River" in use by English-speaking fur traders. However, the 1778 Mitchell Map by John Mitchell records the river as Fiume del Lago, with Samuel Mitchell reproducing the map in 1880, with the river recorded as Lake R..
Henry Schoolcraft in his Narratives in 1820 records the Rum River by its Ojibwe name Missisawgaiegon. By 1832, Tanner's map recorded the name of the river as Rum River. Today, two different Ojibwe names can be found for this river: one indicating the lake of its origin and the other reflecting the English. Due to changes in the Dakota language, two varying river's name appears as well: Watpa waḳaŋ representing the recorded name, Wakpa waḳaŋ reflecting the current name; the current English name is a mistranslation of the one given to it by the Mdewakanton Dakota tribe. Though Watpa waḳaŋ in the Dakota language, by the late 18th-century Europeans interpreted the Mdewakanton Dakota name for the river not as "Spirit" denoting a mystical force, but instead as "spirit" denoting alcohol and since it has been known as the Rum River. There is an international movement to return the river to its previous name on the basis that the current one is a "corruption" of the name's original intent, it is seen as an affront to native sensibilities.
The movement has been endorsed by many tribal and native organizations, human rights organizations, multicultural organizations, the United Nations' Secretariat of the Permanent Forum On Indigenous Issues, the Minnesota Historical Society's Indian Advisory Committee, a Minnesota State Legislator and religious leaders, including Archbishop Harry Flynn and Bishop John Kinney. However, some people still believe it is doubtful that such a change will be effected because the modern usage is so entrenched with communities along the river. Mille Lacs Kathio State Park Rum River State Forest List of Minnesota rivers Minnesota DNR: A Canoe and Boating Guide to the Rum River Rum River – State water trail: Minnesota DNR
In hydrology, the inflow of a body of water is the source of the water in the body of water. It can refer to the average volume of incoming water in unit time, it is contrasted with outflow. All bodies of water have multiple inflows, but one inflow may predominate and be the largest source of water. However, in many cases, no single inflow will predominate and there will be multiple primary inflows. For a lake, the inflow may be a river or stream that flows into the lake. Inflow may be speaking, not flows, but rather precipitation, like rain. Inflow can be used to refer to groundwater recharge; the dictionary definition of inflow at Wiktionary
A lake is an area filled with water, localized in a basin, surrounded by land, apart from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, therefore are distinct from lagoons, are larger and deeper than ponds, though there are no official or scientific definitions. Lakes can be contrasted with rivers or streams, which are flowing. Most lakes streams. Natural lakes are found in mountainous areas, rift zones, areas with ongoing glaciation. Other lakes are found along the courses of mature rivers. In some parts of the world there are many lakes because of chaotic drainage patterns left over from the last Ice Age. All lakes are temporary over geologic time scales, as they will fill in with sediments or spill out of the basin containing them. Many lakes are artificial and are constructed for industrial or agricultural use, for hydro-electric power generation or domestic water supply, or for aesthetic, recreational purposes, or other activities.
The word lake comes from Middle English lake, from Old English lacu, from Proto-Germanic *lakō, from the Proto-Indo-European root *leǵ-. Cognates include Dutch laak, Middle Low German lāke as in: de:Wolfslake, de:Butterlake, German Lache, Icelandic lækur. Related are the English words leak and leach. There is considerable uncertainty about defining the difference between lakes and ponds, no current internationally accepted definition of either term across scientific disciplines or political boundaries exists. For example, limnologists have defined lakes as water bodies which are a larger version of a pond, which can have wave action on the shoreline or where wind-induced turbulence plays a major role in mixing the water column. None of these definitions excludes ponds and all are difficult to measure. For this reason, simple size-based definitions are used to separate ponds and lakes. Definitions for lake range in minimum sizes for a body of water from 2 hectares to 8 hectares. Charles Elton, one of the founders of ecology, regarded lakes as waterbodies of 40 hectares or more.
The term lake is used to describe a feature such as Lake Eyre, a dry basin most of the time but may become filled under seasonal conditions of heavy rainfall. In common usage, many lakes bear names ending with the word pond, a lesser number of names ending with lake are in quasi-technical fact, ponds. One textbook illustrates this point with the following: "In Newfoundland, for example every lake is called a pond, whereas in Wisconsin every pond is called a lake."One hydrology book proposes to define the term "lake" as a body of water with the following five characteristics: it or fills one or several basins connected by straits has the same water level in all parts it does not have regular intrusion of seawater a considerable portion of the sediment suspended in the water is captured by the basins the area measured at the mean water level exceeds an arbitrarily chosen threshold With the exception of the seawater intrusion criterion, the others have been accepted or elaborated upon by other hydrology publications.
The majority of lakes on Earth are freshwater, most lie in the Northern Hemisphere at higher latitudes. Canada, with a deranged drainage system has an estimated 31,752 lakes larger than 3 square kilometres and an unknown total number of lakes, but is estimated to be at least 2 million. Finland has larger, of which 56,000 are large. Most lakes have at least one natural outflow in the form of a river or stream, which maintain a lake's average level by allowing the drainage of excess water; some lakes do not have a natural outflow and lose water by evaporation or underground seepage or both. They are termed endorheic lakes. Many lakes are artificial and are constructed for hydro-electric power generation, aesthetic purposes, recreational purposes, industrial use, agricultural use or domestic water supply. Evidence of extraterrestrial lakes exists. Globally, lakes are outnumbered by ponds: of an estimated 304 million standing water bodies worldwide, 91% are 1 hectare or less in area. Small lakes are much more numerous than large lakes: in terms of area, one-third of the world's standing water is represented by lakes and ponds of 10 hectares or less.
However, large lakes account for much of the area of standing water with 122 large lakes of 1,000 square kilometres or more representing about 29% of the total global area of standing inland water. Hutchinson in 1957 published a monograph, regarded as a landmark discussion and classification of all major lake types, their origin, morphometric characteristics, distribution; as summarized and discussed by these researchers, Hutchinson presented in it a comprehensive analysis of the origin of lakes and proposed what is a accepted classification of lakes according to their origin. This