Fish are gill-bearing aquatic craniate animals that lack limbs with digits. They form a sister group to the tunicates. Included in this definition are the living hagfish and cartilaginous and bony fish as well as various extinct related groups. Tetrapods emerged within lobe-finned fishes, so cladistically they are fish as well. However, traditionally fish are rendered paraphyletic by excluding the tetrapods; because in this manner the term "fish" is defined negatively as a paraphyletic group, it is not considered a formal taxonomic grouping in systematic biology, unless it is used in the cladistic sense, including tetrapods. The traditional term pisces is considered a typological, but not a phylogenetic classification; the earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts. Fish would continue to evolve through the Paleozoic era.
Many fish of the Paleozoic developed external armor. The first fish with jaws appeared in the Silurian period, after which many became formidable marine predators rather than just the prey of arthropods. Most fish are ectothermic, allowing their body temperatures to vary as ambient temperatures change, though some of the large active swimmers like white shark and tuna can hold a higher core temperature. Fish can communicate in their underwater environments through the use of acoustic communication. Acoustic communication in fish involves the transmission of acoustic signals from one individual of a species to another; the production of sounds as a means of communication among fish is most used in the context of feeding, aggression or courtship behaviour. The sounds emitted by fish can vary depending on the stimulus involved, they can produce either stridulatory sounds by moving components of the skeletal system, or can produce non-stridulatory sounds by manipulating specialized organs such as the swimbladder.
Fish are abundant in most bodies of water. They can be found in nearly all aquatic environments, from high mountain streams to the abyssal and hadal depths of the deepest oceans, although no species has yet been documented in the deepest 25% of the ocean. With 33,600 described species, fish exhibit greater species diversity than any other group of vertebrates. Fish are an important resource for humans worldwide as food. Commercial and subsistence fishers hunt fish in wild fisheries or farm them in ponds or in cages in the ocean, they are caught by recreational fishers, kept as pets, raised by fishkeepers, exhibited in public aquaria. Fish have had a role in culture through the ages, serving as deities, religious symbols, as the subjects of art and movies. Fish do not represent a monophyletic group, therefore the "evolution of fish" is not studied as a single event. Early fish from the fossil record are represented by a group of small, armored fish known as ostracoderms. Jawless fish lineages are extinct.
An extant clade, the lampreys may approximate ancient pre-jawed fish. The first jaws are found in Placodermi fossils; the diversity of jawed vertebrates may indicate the evolutionary advantage of a jawed mouth. It is unclear if the advantage of a hinged jaw is greater biting force, improved respiration, or a combination of factors. Fish may have evolved from a creature similar to a coral-like sea squirt, whose larvae resemble primitive fish in important ways; the first ancestors of fish may have kept the larval form into adulthood, although the reverse is the case. Fish are a paraphyletic group: that is, any clade containing all fish contains the tetrapods, which are not fish. For this reason, groups such as the "Class Pisces" seen in older reference works are no longer used in formal classifications. Traditional classification divides fish into three extant classes, with extinct forms sometimes classified within the tree, sometimes as their own classes: Class Agnatha Subclass Cyclostomata Subclass Ostracodermi † Class Chondrichthyes Subclass Elasmobranchii Subclass Holocephali Class Placodermi † Class Acanthodii † Class Osteichthyes Subclass Actinopterygii Subclass Sarcopterygii The above scheme is the one most encountered in non-specialist and general works.
Many of the above groups are paraphyletic, in that they have given rise to successive groups: Agnathans are ancestral to Chondrichthyes, who again have given rise to Acanthodiians, the ancestors of Osteichthyes. With the arrival of phylogenetic nomenclature, the fishes has been split up into a more detailed scheme, with the following major groups: Class Myxini Class Pteraspidomorphi † Class Thelodonti † Class Anaspida † Class Petromyzontida or Hyperoartia Petromyzontidae Class Conodonta † Class Cephalaspidomorphi † Galeaspida † Pituriaspida † Osteostraci † Infraphylum Gnathostomata Class Placodermi † Class Chondrichthyes Class Acanthodii † Superclass Osteichthy
Winnemucca Lake is a dry lake bed that features the oldest known petroglyphs in North America. It is in northwest sits astride the border between Washoe and Pershing counties; until the 1930s, it was a shallow lake, but was dried when a dam and a road were built that combined to restrict and block water flow. It was designated as a National Wildlife Refuge, but its status as a refuge was removed due to the lack of water. Winnemucca Lake is home to several petroglyphs long believed to be old. In 2013, researchers dated the carvings to between 10,500 years ago. Either date would make them the oldest known petroglyphs found in North America; the carvings lie within the Pyramid Lake Indian Reservation. Winnemucca Lake is a sub-basin within the Lahontan Basin in northwestern Nevada, it is on the dividing line between Washoe and Pershing counties. The lake bed lies between the Lake Range on the west and the Nightingale Mountains and Selenite Range to the east. Winnemucca Lake is about 7 km wide; the lake bed is at an elevation of 1,150 m, below the water level of adjacent Pyramid Lake.
Winnemucca Lake may have been dry when John Frémont came through in 1843-44. Frémont's 1844 map indicates that he traveled to the west of Winnemucca Lake and does not map the Winnemucca Lake valley; the Elko Free Press reports that there was a flood in 1862 that filled the lake to 80 feet, but Russell states that the level was low in 1862. In 1865, Winnemucca Lake was the site of the Battle of Mud Lake where 29 soldiers from the 1st Nevada Volunteer Cavalry Battalion led by Captain Almond B. Wells killed 29 Smoke Creek Indians. At least two of those killed were women more. Sarah Winnemucca wrote "I had one baby brother killed there. My sister ran away; as she ran the soldiers ran after her but thanks be to the Good Father in the Spirit land my dear sister got away. This killed my poor papa."The maximum level of the lake was 26 meters in the 1880'sWinnemucca Lake was a shallow tule-filled lake and an important stop for migrating waterfowl. After the Derby Dam was built on the Truckee River in 1903, State Route 447 was built, Winnemucca Lake dried out and has remained seasonally dry since the late 1930s.
In 1936, Franklin D. Roosevelt made an effort to rescue the lake and designated the area as the Winnemucca Lake National Wildlife Refuge. In 1962, the refuge designation was removed, making this area the first refuge designation lost because of lack of water; the western end of Winnemucca Lake is home to several boulders carved with petroglyphs that lie within the Pyramid Lake Indian Reservation. The site designated 26Wa3329, was first described by Connick and Connick in 1992; the team and Robert E. Connick, classified it as unusual, very early. In 1994, geochemist Larry Benson determined the designs had been carved into a branch form of tufa, a type of limestone; the research showed that the limestone was deposited between 16,200 and 14,800 years ago, but no specific date for the carvings was suggested. In 2013, a team of researchers from the University of Colorado at Boulder collected carbonate crust and shallow-water algal formations from the site, they used radiocarbon dating and strontium isotope analysis to establish a window of when the lake level was low enough to allow access to the rocks.
Sedimentary cores were collected from nearby Pyramid Lake and subjected to analysis to determine rise and fall of the waterline over time. More precise methods of dating would have required taking scrapings from the grooves of the petroglyphs, not allowed by the Pyramid Lake Paiute Tribe. However, Benson was allowed to use non-invasive techniques to examine the petroglyphs that allowed him to work to the side of the carvings; the research was published in the Journal of Archaeological Science. Dating of the lowest carbonate crust yielded a date of 10,200 to 9,800 years ago; the algal formation dating suggested the waterline was sufficiently low from 12,600 to 11,400 years ago. The sedimentary core analysis of Pyramid Lake showed the waterline began to fall about 15,000 years ago, reaching a low 13,300 years ago. At about 13,200 years ago it rose again, had intermittent low periods thereafter; the broad consistencies among the various dating methods allowed the research team to conclude the petroglyph rocks were above the waterline, thus available for carving, from 14,800 and 13,200 years ago and between 11,300 and 10,500 years ago.
Additionally, the younger date range is consistent with the date of textiles found within the Winnemucca sub-basin and the date of various human artifacts found within the Lahontan Basin. The younger dates align with the estimated age of the Spirit Cave mummy found nearby. Either date range would make the petroglyphs; the older date would correspond to the estimated time of the first human migrations into North America and to remains found in Paisley Cave, Oregon. The oldest carvings in North America were thought to be those estimated to be 7,300 years old found at Long Lake, in Oregon; the rocks include both simple petroglyphs such as straight lines and swirls and more complex petroglyphs that resemble trees, flowers, or the veins of a leaf. There is an intricate diamond pattern on one roc
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
American white pelican
The American white pelican is a large aquatic soaring bird from the order Pelecaniformes. It breeds in interior North America, moving south and to the coasts, as far as Central America and South America, in winter; the German naturalist Johann Friedrich Gmelin described the American white pelican in 1789. The scientific name means "red-billed pelican", from the Latin term for a pelican and erythrorhynchos, derived from the Ancient Greek words erythros + rhynchos; the American white pelican rivals the trumpeter swan, with a similar overall length, as the longest bird native to North America. Both large and plump, it has an overall length of about 50–70 in, courtesy of the huge beak which measures 11.3–15.2 in in males and 10.3–14.2 in in females. It has a wingspan of about 95–120 in; the species has the second largest average wingspan of any North American bird, after the California condor. This large wingspan allows the bird to use soaring flight for migration. Body weight can range between 7.7 and 30 lb, although these birds average between 11 and 20 lb.
One mean body mass of 15.4 lb was reported. Another study found mean weights to be somewhat lower than expected, with eleven males averaging 13.97 lb and six females averaging 10.95 lb. Among standard measurements, the wing chord measures 20–26.7 in and the tarsus measures 3.9–5.4 in long. The plumage is entirely bright white, except the black primary and secondary remiges, which are hardly visible except in flight. From early spring until after breeding has finished in mid-late summer, the breast feathers have a yellowish hue. After moulting into the eclipse plumage, the upper head has a grey hue, as blackish feathers grow between the small wispy white crest; the bill is huge and flat on the top, with a large throat sac below, and, in the breeding season, is vivid orange in color as are the iris, the bare skin around the eye, the feet. In the breeding season, there is a laterally flattened "horn" on the upper bill, located about one-third the bill's length behind the tip; this is the only one of the eight species of pelican to have a bill "horn".
The horn is shed after the birds have laid their eggs. Outside the breeding season the bare parts become duller in color, with the naked facial skin yellow and the bill and feet an orangy-flesh color. Apart from the difference in size and females look alike. Immature birds remiges, their bare parts are dull grey. Chicks are naked at first grow white down feathers all over, before moulting to the immature plumage. American white pelicans nest in colonies of several hundred pairs on islands in remote brackish and freshwater lakes of inland North America; the most northerly nesting colony can be found on islands in the rapids of the Slave River between Fort Fitzgerald and Fort Smith, Northwest Territories. Several groups have been visiting the Useless Bay bird sanctuary since 2015. About 10–20% of the population uses Gunnison Island in the Great Basin's Great Salt Lake as a nesting ground; the southernmost colonies are in northeastern California. Nesting colonies exist as far south as Albany County in southern Wyoming.
They winter on the Pacific and Gulf of Mexico coasts from central California and Florida south to Panama, along the Mississippi River at least as far north as St. Louis, Missouri. In winter quarters, they are found on the open seashore, preferring estuaries and lakes, they avoid the open ocean on migration. But stray birds blown off course by hurricanes, have been seen in the Caribbean. In Colombian territory it has been recorded first on February 22, 1997, on the San Andrés Island, where they might have been swept by Hurricane Marco which passed nearby in November 1996. Since there have been a few observations to pertain to this species on the South American mainland, e.g. at Calamar. Wild American white pelicans may live for more than 16 years. In captivity, the record lifespan stands at over 34 years. Unlike the brown pelican, the American white pelican does not dive for its food. Instead it catches its prey while swimming; each bird eats more than 4 pounds of food a day fish such as Cypriniformes like Common carp, Lahontan Tui chub and shiners, Perciformes like Sacramento perch or Yellow perch, Salmoniformes like Rainbow trout and jackfish.
Other animals eaten by these birds are crayfish and amphibians, sometimes larval salamanders. Birds nesting on saline lakes, where food is scarce, will travel great distances to better feeding grounds. American white pelicans like to come together in groups of a dozen or more birds to feed, as they can thus cooperate and corral fish to one another; when this is not possible – for example in deep water, where fish can escape by diving out of reach –, they prefer to forage alone. But the birds steal food on occasion from other birds, a practice known as kleptoparasitism. White pelicans are known to steal fish from other pelicans and cormorants from the surface of the water and, in one case, from a great blue heron while both large birds were in flight; as noted above, they are colonial breeders, with up to 5,000 pairs per site. The birds arrive on the breeding grounds in April. During the breeding season, both males and females develop a pronounced bump on the top
Derby Dam is a diversion dam built in 1904-05 on the Truckee River, located about 20 miles east of Reno in Storey and Washoe counties in Nevada, United States. It diverts water into the Truckee Canal; the canal feeds Lake Lahontan reservoir in the Carson River watershed, where it is used for irrigation. It was the first project of the newly organized U. S. Reclamation Service, organized by the Reclamation Act of 1902; as a result of the diversion, Winnemucca Lake lost inflow and dried up, Pyramid Lake lost more than 80 feet in elevation, resulting in the near-extinction of the Lahontan cutthroat trout. The dam is operated by the Truckee-Carson Irrigation District, it was named after the Derby Southern Pacific Railroad station. The dam was constructed for the U. S. Bureau of Reclamation following an authorization for construction issued on March 14, 1903. Construction commenced on October 2, 1903 and was completed on May 20, 1905; the project was authorized on March 1903 by Secretary of the Interior Ethan A. Hitchcock.
The dam is an original feature of the Newlands Reclamation Project, named after Nevada Congressman Francis Newlands, who sponsored the Reclamation Act. Not a dam in Newlands, Nevada launched the project, it one the first of five projects authorized and built under the Reclamation Act of 1902. With passage of the act, the federal government assumed a major role in designing and constructing large-scale irrigation projects throughout the West; the diversion dam is part of the network of water storage and conveyance structures that provides water for irrigating about 73,000 acres of farmland in an area that receives less than 4.5 inches of annual precipitation. The dam is not designed for water storage, it is a low 31 feet high concrete structure that diverts water from the Truckee River into the Truckee Canal and two main project canals, the Southside Main Canal and the Northside Main Canal. It was listed on the National Register of Historic Places in 1978 as the "Derby Diversion Dam." Water diverted at Derby Dam to farms in Lahontan Valley constitutes as much as three-fourths of the flow of the Truckee River, the largest diversion of water from the Truckee River after it flows from Lake Tahoe.
The reduction in flow to Pyramid Lake and the inability of Lahontan cutthroat trout to bypass the dam for spawning eliminated them from Lake Lahontan and it's tributaries and caused the near extinction of the species. But in 1979 a remnant population of the original Pyramid Lake cutthroat trout was discovered in a small brook on Pilot Peak, on the Nevada/Utah border; this population was used to restock Lake Lahontan. Winnemucca Lake Cui-ui DSSAM Model This article contains content from United States government sources in the public domain
The cui-ui is a large sucker fish endemic to Pyramid Lake and, prior to its desiccation in the 20th century, Winnemucca Lake in northwestern Nevada. It feeds on zooplankton and on nanoplankton; the maximum size of male cui-ui is 53 cm and 1.6 kg, while females reach 64 cm and 2.7 kg. The life span of cui-ui is about forty years, but the fish do not reach sexual maturity until at least age eight; the cui-ui is an endangered species, one of the few surviving members of its genus. The cui-ui population is improving in numbers, having attained an estimated population exceeding one million in 1993, thanks to the efforts of the U. S. Environmental Protection Agency in analysis of the Truckee River spawning grounds and of the Nevada Department of Environmental Protection and EPA in following up on protection measures; the reason the cui-ui remains endangered is the recent history of recruitment variation, illustrating that in many years of the 1970s and 1980s there was no recruitment whatsoever due to unsuccessful spawning in an unfavorable water quality and water flow environment of the Truckee River.
The species' outlook is somewhat sanguine, since there is a published recovery plan based on an enhanced understanding of Pyramid Lake and Truckee River water quality, the adoption of a protection plan by the U. S. Congress. Pyramid Lake, the second largest natural lake in the western U. S. prior to construction of the Derby Dam, has been the focus of several water quality investigations, the most detailed starting in the mid-1980s. Under direction of the U. S. Environmental Protection Agency, a comprehensive dynamic hydrology transport model was developed by Earth Metrics Inc.. Analytes addressed included reactive phosphate, dissolved oxygen and ten other parameters. Based upon use of the model, some decisions have been influenced to enhance Pyramid Lake water quality and aid the viability of Pyramid Lake biota, including the cui-ui; the dynamic river model was useful for analyzing Truckee River temperature variations, since the cui-ui swim upstream to spawn, their fry are vulnerable to elevations in river temperature.
The cui-ui is potamodromous, will attempt to ascend the Truckee River to spawn in mid-April. If inflow is insufficient to permit this, the cui-ui may attempt to spawn in Pyramid Lake, but with little success due to the salinity of that lake. Water releases from the Boca reservoir and Stampede reservoirs are timed to assist the spawning run, although in drought years this water is reserved for the Reno metropolitan area; these releases are critical to successful spawning since low warm flows at the Truckee River delta are inhospitable to upstream migration of adults. Several hatcheries are maintained by the Paiute nation to ensure that such a situation does not impact the long term viability of the cui-ui; these measures have increased cui-ui populations, although it is still listed as an endangered species. The Pyramid Lake band of Northern Paiute called themselves the "Cuiyui Ticutta", which means cui-ui eaters. Together with the Lahontan cutthroat trout the cui-ui was an important food supply for the Cuiyui Tikutta and neighboring Paiute bands who would travel to Pyramid Lake to share in the harvest during the spring spawning runs.
Subsequent to European American settlement of western Nevada in the 1860s many Cuiyui Ticutta made a living by selling fish, although the European Americans preferred trout to cui-ui. Cui-ui were still important for subsistence, despite Bureau of Indian Affairs attempts to encourage farming and discourage fishing. Following the construction of Derby Dam in 1905 and diversion of much of the Truckee River's flow, the Pyramid Lake fishery declined and by 1930 it was no longer capable of supplying subsistence food. Although conditions have improved the cui-ui are now managed for symbolic and ecological purposes, are not a food source. Surface runoff Thermal pollution Koch Cui-ui Hatchery U. S. Department of Interior cui-ui article