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Standard Length
Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish measured from the tip of the snout to the posterior end of the last vertebra or to the posterior end of the midlateral portion of the hypural plate. Simply put, this measurement excludes the length of the caudal (tail) fin. * Total length (TL) is the length of a fish measured from the tip of the snout to the tip of the longer lobe of the caudal fin, usually measured with the lobes compressed along the midline. It is a straight-line measure, not measured over the curve of the body. Standard length measurements are used with Teleostei (most bony fish), while total length measurements are used with Myxini (hagfish), Petromyzontiformes (lampreys), and (usually) Elasmobranchii (sharks and rays), as well as some other fishes. Total length meas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Anatomy
Fish anatomy is the study of the form or morphology of fish. It can be contrasted with fish physiology, which is the study of how the component parts of fish function together in the living fish. In practice, fish anatomy and fish physiology complement each other, the former dealing with the structure of a fish, its organs or component parts and how they are put together, such as might be observed on the dissecting table or under the microscope, and the latter dealing with how those components function together in living fish. The anatomy of fish is often shaped by the physical characteristics of water, the medium in which fish live. Water is much denser than air, holds a relatively small amount of dissolved oxygen, and absorbs more light than air does. The body of a fish is divided into a head, trunk and tail, although the divisions between the three are not always externally visible. The skeleton, which forms the support structure inside the fish, is either made of cartilage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slot Limit
A slot limit is a tool used by fisheries managers to regulate the size of fish that can legally be harvested from particular bodies of water. Usually set by state fish and game departments, the protected slot limit prohibits the harvest of fish where the lengths, measured from the snout to the end of the tail, fall within the protected interval. For example, on a body of water where there is a protected slot limit on largemouth bass between , largemouth between those lengths may not be harvested. In this example largemouth bass shorter than and longer than may be removed from the water and kept for personal use in accordance with local fishing regulations. Slot limits are based on the principle that bass populations exhibit different habitat requirements during different phases of their lives. Slot limits focus on protecting one segment of the life history which can influence overall fishing success. A minimum landing size is a similar regulation in commercial fishing. "Slot" ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fishkeeping
Fishkeeping is a popular hobby, practiced by aquarists, concerned with keeping fish in a home aquarium or garden pond. There is also a piscicultural fishkeeping industry, serving as a branch of agriculture. Origins of fishkeeping Fish have been raised as food in pools and ponds for thousands of years. Brightly colored or tame specimens of fish in these pools have sometimes been valued as pets rather than food. Many cultures, ancient and modern, have kept fish for both functional and decorative purposes. Ancient Sumerians kept wild-caught fish in ponds, before preparing them for meals. Depictions of the sacred fish of Oxyrhynchus kept in captivity in rectangular temple pools have been found in ancient Egyptian art. Similarly, Asia has experienced a long history of stocking rice paddies with freshwater fish suitable for eating, including various types of catfish and cyprinid. Selective breeding of carp into today's popular and completely domesticated koi and fancy goldfis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ichthyology
Ichthyology is the branch of zoology devoted to the study of fish, including bony fish ( Osteichthyes), cartilaginous fish ( Chondrichthyes), and jawless fish ( Agnatha). According to FishBase, 33,400 species of fish had been described as of October 2016, with approximately 250 new species described each year. Etymology The word is derived from the Greek words ἰχθύς, ''ikhthus'', meaning "fish"; and λογία, ''logia'', meaning "to study". History The study of fish dates from the Upper Paleolithic Revolution (with the advent of "high culture"). The science of ichthyology was developed in several interconnecting epochs, each with various significant advancements. The study of fish receives its origins from humans' desire to feed, clothe, and equip themselves with useful implements. According to Michael Barton, a prominent ichthyologist and professor at Centre College, "the earliest ichthyologists were ''hunters and gatherers'' who had learned how to obtain the most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standard Weight In Fish
Standard weight in fish is the typical or expected weight at a given total length for a specific species of fish. Most standard weight equations are for freshwater fish species. Weight-length curves are developed by weighing and measuring samples of fish from the population. Methods of obtaining such samples include creel surveys, or measurements of fish caught by commercial fishermen, recreational fishermen and/or by the researchers themselves. Some scientists use cast nets, trotlines, or other means to catch many individual fish at once for measurement. To determine a standard weight equation, several data sets or weight-length relationships representing a species across its range are used. As fish grow in length, they increase in weight. The relationship between weight and length is not linear. The relationship between length (''L'') and weight (''W'') can be expressed as: :W = aL^b\!\, When the equation is for standard weight, the standard weight for a given length is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ichthyology Terms
This glossary of ichthyology is a list of definitions of terms and concepts used in ichthyology, the study of fishes. A B C D E F G H I J K L M N O P R S T U V W {{glossaryend * Fishkeeping Ichthyology Ichthyology is the branch of zoology devoted to the study of fish, including bony fish ( Osteichthyes), cartilaginous fish ( Chondrichthyes), and j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lutjanus Campechanus
The northern red snapper (''Lutjanus campechanus'') is a species of marine ray-finned fish, a snapper belonging to the family Lutjanidae. It is native to the western Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico, where it inhabits environments associated with reefs. This species is commercially important and is also sought-after as a game fish. Taxonomy The northern red snapper was first formally described in 1860 as ''Mesoprion campechanus'' by the Cuban zoologist Felipe Poey with the type locality given as Campeche in Mexico. The specific name reflects the type locality. Characteristics The northern red snapper's body is very similar in shape to other snappers, such as the mangrove snapper, mutton snapper, lane snapper, and dog snapper. All feature a sloped profile, medium-to-large scales, a spiny dorsal fin, and a laterally compressed body. Northern red snapper have short, sharp, needle-like teeth, but they lack the prominent upper canine teeth foun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Drum
The black drum (''Pogonias cromis''), also known as the drum or drummer, is a saltwater fish similar to its cousin, the red drum. It is in the genus '' Pogonias''. Though most specimens are generally found in the 5-30 lb (2–14 kg) range, the black drum is well known as the largest of all the drum family with some specimens reaching excesses of 90 lb (40 kg). The world record black drum was just over 113 lb (51 kg). They are often black and/or gray in color with juvenile fish having distinctive dark stripes over a gray body. Their teeth are rounded and they have powerful jaws capable of crushing oysters and other shellfish. It is recommended those over 15 lb (7 kg) should be released. Black drum are capable of producing tones between 100 Hz and 500 Hz when performing mating calls. Habits, distribution, and characteristics The black drum is usually found in or near brackish waters. Larger, older fish are more commonly found in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grenadier Basic External Features
A grenadier ( , ; derived from the word '' grenade'') was originally a specialist soldier who threw hand grenades in battle. The distinct combat function of the grenadier was established in the mid-17th century, when grenadiers were recruited from among the strongest and largest soldiers. By the 18th century, the grenadier dedicated to throwing hand grenades had become a less necessary specialist, yet in battle, the grenadiers were the physically robust soldiers who led assaults, such as storming fortifications in the course of siege warfare. Certain countries such as France (Grenadiers à Cheval de la Garde Impériale) and Argentina (Regiment of Mounted Grenadiers) established units of Horse Grenadiers and for a time the British Army had Horse Grenadier Guards. Like their infantry grenadier counterparts, these horse-mounted soldiers were chosen for their size and strength (heavy cavalry). Today, the term is also used to describe a soldier armed with a grenade launcher, a weapo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minimum Landing Size
The minimum landing size (MLS) is the smallest fish measurement at which it is legal to keep or sell a fish. The MLS depends on the species of fish. Sizes also vary around the world, as they are legal definitions which are defined by the local regulatory authority. Commercial trawl and seine fisheries can control the size of their catch by adjusting the mesh size of their nets. Effect of selection on fish sizes The idea behind this limitation is that only the older, mature fish get taken, leaving juveniles behind to continue breeding and propagating their species. There is some criticism of this legal requirement, however, as it applies selection pressure to the fish: as the larger fish get taken, the genes for larger size are reduced or removed from the gene pool, while fish that mature at a smaller size continue breeding. The average size of fish shrinks over time. This has led to a collapse in the amount of fish being caught in some fisheries. Aboriginal Australians around Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Batoidea
Batoidea is a superorder of cartilaginous fishes, commonly known as rays. They and their close relatives, the sharks, comprise the subclass Elasmobranchii. Rays are the largest group of cartilaginous fishes, with well over 600 species in 26 families. Rays are distinguished by their flattened bodies, enlarged pectoral fins that are fused to the head, and gill slits that are placed on their ventral surfaces. Anatomy Batoids are flat-bodied, and, like sharks, are cartilaginous fish, meaning they have a boneless skeleton made of a tough, elastic cartilage. Most batoids have five ventral slot-like body openings called gill slits that lead from the gills, but the Hexatrygonidae have six. Batoid gill slits lie under the pectoral fins on the underside, whereas a shark's are on the sides of the head. Most batoids have a flat, disk-like body, with the exception of the guitarfishes and sawfishes, while most sharks have a spindle-shaped body. Many species of batoid have developed their p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ichthyology
Ichthyology is the branch of zoology devoted to the study of fish, including bony fish ( Osteichthyes), cartilaginous fish ( Chondrichthyes), and jawless fish ( Agnatha). According to FishBase, 33,400 species of fish had been described as of October 2016, with approximately 250 new species described each year. Etymology The word is derived from the Greek words ἰχθύς, ''ikhthus'', meaning "fish"; and λογία, ''logia'', meaning "to study". History The study of fish dates from the Upper Paleolithic Revolution (with the advent of "high culture"). The science of ichthyology was developed in several interconnecting epochs, each with various significant advancements. The study of fish receives its origins from humans' desire to feed, clothe, and equip themselves with useful implements. According to Michael Barton, a prominent ichthyologist and professor at Centre College, "the earliest ichthyologists were ''hunters and gatherers'' who had learned how to obtain the most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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