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Spawning Bed
A spawning bed is an underwater solid surface on which fish spawn to reproduce themselves. In fishery management, a spawning bed is an artificial bed constructed by wildlife professionals in order to improve the ability of desired game fish to reproduce. Increasing the spawning ability of a fish population may reduce pressure on a fishery and improve the productivity of supplemental stocking from fish hatcheries. In the inland waters of North America, a typical spawning bed will consist of a series of concrete boxes filled with aggregate gravel. The concept is credited to the Kentucky Department of Fish and Wildlife. Joe McFarland, "Making Bass Beds", ''Outdoor Illinois'' XVI:5 (May 2008), pages 16-17. In a typical example of spawning beds in action, the Illinois Department of Natural Resources has installed approximately 50 largemouth bass spawning beds in Crab Orchard Lake in southern Illinois. Joe McFarland, "The Unique Refuge", ''Outdoor Illinois'' XIX:3 (March 2011), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of living fish species are ray-finned fish, belonging to the class Actinopterygii, with around 99% of those being teleosts. 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, diversifying into a wide variety of forms. Many fish of the Paleozoic developed external armor that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many (such as sharks) became formidable marine predators rather than just the prey of arthropods. Mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spawn (biology)
Spawn is the Egg cell, eggs and Spermatozoa, sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of releasing the eggs and sperm, and the act of both sexes is called spawning. Most aquatic animals, except for aquatic mammals and marine reptile, reptiles, reproduce through the process of spawning. Spawn consists of the reproductive cells (gametes) of many aquatic animals, some of which will become fertilized and produce offspring. The process of spawning typically involves females releasing Ovum, ova (unfertilized eggs) into the water, often in large quantities, while males simultaneously or sequentially release spermatozoa (milt) to fertilize the eggs. Most fish reproduce by spawning, as do most other aquatic animals, including crustaceans such as crabs and shrimps, molluscs such as oysters and squid, echinoderms such as sea urchins and sea cucumbers, amphibians such as frogs and newts, aquatic insects such as mayflies and mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fishery Management
The goal of fisheries management is to produce sustainable biological, environmental and socioeconomic benefits from renewable aquatic resources. Wild fisheries are classified as renewable when the organisms of interest (e.g., fish, shellfish, amphibians, reptiles and marine mammals) produce an annual biological surplus that with judicious management can be harvested without reducing future productivity. Fishery management employs activities that protect fishery resources so sustainable exploitation is possible, drawing on fisheries science and possibly including the precautionary principle. Modern fisheries management is often referred to as a governmental system of appropriate environmental management rules based on defined objectives and a mix of management means to implement the rules, which are put in place by a system of monitoring control and surveillance. A popular approach is the ecosystem approach to fisheries management. According to the Food and Agriculture Organiz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Hatchery
A fish hatchery is a place for artificial breeding, hatching, and rearing through the early life stages of animals—finfish and shellfish in particular.Crespi V., Coche A. (2008) Food and Agriculture Organization of the United Nations (FAO) Glossary of Aquacultur/ref> Hatcheries produce Fish larva, larval and juvenile fish, shellfish, and crustaceans, primarily to support the aquaculture industry where they are transferred to on-growing systems, such as fish farms, to reach harvest size. Some species that are commonly raised in hatcheries include Pacific oysters, shrimp, Indian prawns, salmon, tilapia and scallops. The value of global aquaculture farming is estimated to be US$98.4 billion in 2008 with China significantly dominating the market; however, the value of aquaculture hatchery and nursery production has yet to be estimated. Additional hatchery production for small-scale domestic uses, which is particularly prevalent in South-East Asia or for conservation programmes, ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Construction Aggregate
Construction aggregate, or simply aggregate, is a broad category of coarse- to medium-grained particulate material used in construction, including sand, gravel, crushed stone, slag, recycled concrete and geosynthetic aggregates. Aggregates are the most mined materials in the world. Aggregates are a component of composite materials such as concrete and asphalt; the aggregate serves as reinforcement to add strength to the overall composite material. Due to the relatively high hydraulic conductivity value as compared to most soils, aggregates are widely used in drainage applications such as foundation and French drains, septic drain fields, retaining wall drains, and roadside edge drains. Aggregates are also used as base material under foundations, roads, and railroads. In other words, aggregates are used as a stable foundation or road/rail base with predictable, uniform properties (e.g. to help prevent differential settling under the road or building), or as a low-cost exten ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kentucky Department Of Fish And Wildlife
The Kentucky Department of Fish and Wildlife Resources, an agency of the Kentucky Tourism, Arts and Heritage Cabinet, is responsible for the conservation of wildlife resources and for boating projects in the state. A commissioner appointed by the Fish and Wildlife Commission heads the department. The commission--which oversees the department's commissioner and promulgates regulations governing fishing, hunting and boating--is a nine-member bipartisan board appointed by the governor from a list of candidates nominated by active hunters and anglers in each of nine geographic districts in the state. Financial support of the Department is derived through the sale of hunting and fishing licenses, boat registrations, federal grants and numerous other receipts. The department has a $68 million budget and employs about 400 full-time staff and more than 100 interim (seasonal) employees and contract labor. Mission statement The department's mission is to conserve, protect and enhance Kentu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Illinois Department Of Natural Resources
The Illinois Department of Natural Resources (IDNR) is the code department of the Illinois state government that operates the state parks and state recreation areas, enforces the fishing and game laws of Illinois, regulates Illinois coal mines, operates the Illinois State Museum system, and oversees scientific research into the soil, water, and mineral resources of the state. In 2017, the Illinois Historic Preservation Division was added to its portfolio. It is headquartered in the state capital of Springfield. History The former ''Illinois Department of Conservation'' was reorganized into the Illinois Department of Natural Resources by executive order in 1995. The reorganization, codified into state law by Public Act 89-50, also added functions of the former ''Illinois Department of Energy and Natural Resources'' and the ''Illinois Department of Mines and Minerals'' to the agglomerated agency Organization As of 2009, the Illinois Department of Natural Resources was divided up ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Largemouth Bass
The largemouth bass (''Micropterus salmoides'') is a carnivorous freshwater gamefish in the Centrarchidae ( sunfish) family, a species of black bass native to the eastern and central United States, southeastern Canada and northern Mexico, but widely introduced elsewhere. It is known by a variety of regional names, such as the widemouth bass, bigmouth bass, black bass, bucketmouth, largies, Potter's fish, Florida bass, Florida largemouth, green bass, bucketmouth bass, Green trout, gilsdorf bass, Oswego bass, LMB, and southern largemouth and northern largemouth. The largemouth bass is the state fish of Georgia and Mississippi, and the state freshwater fish of Florida and Alabama. Taxonomy The largemouth bass was first formally described as ''Labrus salmoides'' in 1802 by the French naturalist Bernard Germain de Lacépède with the type locality given as the Carolinas. Lacépède based his description on an illustration of a specimen collected by Louis Bosc near Charleston, S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crab Orchard Lake
Crab Orchard Lake is a 6,965-acre (28.2 km²) reservoir in Williamson County, Illinois. It is the centerpiece of the Crab Orchard National Wildlife Refuge. It is fed by Devils Kitchen Lake and Little Grassy Lake, which are also within the National Wildlife Refuge. Crab Orchard Lake was created when Crab Orchard Creek, a tributary of the Big Muddy River in southern Illinois, was dammed in the 1930s for purposes of recreation and flood control. The Crab Orchard National Wildlife Refuge was established August 5, 1947 following the transfer of all land previously held by the Crab Orchard Creek Project and the Illinois Ordnance Plant to the United States Fish and Wildlife Service. The lake offers opportunities for boating, camping, fishing, and swimming. Two campgrounds, Blue Heron and Crab Orchard, operate on the northern side of the lake.Joe McFarland, "The Unique Refuge", ''Outdoor Illinois'' XIX:3 (March 2011), pages 14-15. The Illinois Department of Natural Resources ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geomorphology
Geomorphology (from Ancient Greek: , ', "earth"; , ', "form"; and , ', "study") is the scientific study of the origin and evolution of topographic and bathymetric features created by physical, chemical or biological processes operating at or near Earth's surface. Geomorphologists seek to understand why landscapes look the way they do, to understand landform and terrain history and dynamics and to predict changes through a combination of field observations, physical experiments and numerical modeling. Geomorphologists work within disciplines such as physical geography, geology, geodesy, engineering geology, archaeology, climatology, and geotechnical engineering. This broad base of interests contributes to many research styles and interests within the field. Overview Earth's surface is modified by a combination of surface processes that shape landscapes, and geologic processes that cause tectonic uplift and subsidence, and shape the coastal geography. Surface processes co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Artificial Reef
An artificial reef is a human-created underwater structure, typically built to promote marine life in areas with a generally featureless bottom, to control erosion, block ship passage, block the use of trawling nets, or improve surfing. Many reefs are built using objects that were built for other purposes, such as by sinking oil rigs (through the Rigs-to-Reefs program), scuttling ships, or by deploying rubble or construction debris. Other artificial reefs are purpose-built (e.g. the reef balls) from PVC or concrete. Shipwrecks may become artificial reefs when preserved on the seafloor. Regardless of construction method, artificial reefs generally provide hard surfaces where algae and invertebrates such as barnacles, corals, and oysters attach; the accumulation of attached marine life in turn provides intricate structures and food for assemblages of fish. History The construction of artificial reefs began in ancient times. Persians blocked the mouth of the Tigris River to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Underwater Diving
Underwater diving, as a human activity, is the practice of descending below the water's surface to interact with the environment. It is also often referred to as diving, an ambiguous term with several possible meanings, depending on context. Immersion in water and exposure to high ambient pressure have physiological effects that limit the depths and duration possible in ambient pressure diving. Humans are not physiologically and anatomically well-adapted to the environmental conditions of diving, and various equipment has been developed to extend the depth and duration of human dives, and allow different types of work to be done. In ambient pressure diving, the diver is directly exposed to the pressure of the surrounding water. The ambient pressure diver may dive on breath-hold (freediving) or use breathing apparatus for scuba diving or surface-supplied diving, and the saturation diving technique reduces the risk of decompression sickness (DCS) after long-duration deep dives ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
