Cleaner Fish ... The symbiosis does not break down because the abundance of these parasites varies significantly seasonally and spatially, and the overall benefit to the larger fish outweighs any cheating on the part of the smaller... Mimicry Many cleaner fish have a distinctive combination of a long narrow body, a longitudinal stripe, a blue colour, and small size... "Convergent signalling among cleaners, using size, stripes and colour, should facilitate their recognition by fish clients." The sabre-toothed blenny Aspidontus taeniatus is a blenny that mimics the ritualised dance the cleaner wrasse makes when passing fish swim by...
Fish Anatomy ... The caudal peduncle is the narrow part of the fish's body to which the caudal or tail fin is attached. The hypural joint is the joint between the caudal fin and the last of the vertebrae...
Fish Hook ... Historically, many ancient fish hooks were barbless, but today a barbless hook is used to make hook removal and fish release less stressful on the fish...
Fish Locomotion ... Body/caudal fin propulsion There are five groups that differ in the fraction of their body that is displaced laterally : Anguilliform locomotion In some long, slender fish – eels, for example – there is little increase in the amplitude of the flexion wave as it passes along the body... Sub-carangiform locomotion Here, there is a more marked increase in wave amplitude along the body with the vast majority of the work being done by the rear half of the fish... Ocean sunfish, for example, have a completely different system, and many small fish use their pectoral fins for swimming as well as for steering and dynamic lift...
Fishery Products ... Fish and other aquatic organisms are also processed into various food and non-food products. History In Ancient Roman society, garum, a type of fish sauce condiment, was popular...
Fishkeeping ... In the tropics, tropical fish can be kept in garden ponds, but in the temperate zone species such as goldfish, koi, and orfe work better... Marine aquaria can be exceedingly beautiful, due to the attractive colors and shapes of the corals and the coral reef fish they host... Temperate zone marine fish are not as commonly kept in home aquaria, primarily because they do not thrive at room temperature...
Live Fish Trade ... The live food fish trade is a global system that links fishing communities with markets, primarily in Hong Kong and mainland China... Consumer demand Within the live food trade there are certain types of fish demanded more often by consumers, particularly smaller and medium-sized fish... According to the book While Stocks Last: The Live Reef Food Fish Trade consumer demand has caused the fish captured on coral reefs to be the most valued fish in the trade...
Animal Navigation ... William Tinsley Keeton (1933-1980) studied homing pigeons, showing that they were able to navigate using the earth's magnetic field, the sun, as well as both olfactory and visual cues. Donald Griffin (1915-2003) studied echolocation in bats, demonstrating that it was possible and that bats used this mechanism to detect and track prey, and to "see" and thus navigate through the world around them...
Overfishing ... In these locations, overfishing has not only proved disastrous to fish stocks but also to the fishing communities relying on the harvest... The United Kingdom has created elements within this plan to attempt to restore this fishery, but the expanding global human population and the expanding demand for fish has reached a point where demand for food threatens the stability of these fisheries, if not the species' survival... Deep sea fish grow slowly because of limited food, have slow metabolisms, low reproductive rates, and many don't reach breeding maturity for 30 to 40 years...
Scale (anatomy) ... They come in two forms: Cycloid scales have a smooth outer edge, and are most common on fish with soft fin rays, such as salmon and carp... Ctenoid scales have a toothed outer edge, and are usually found on fish with spiny fin rays, such as bass and crappie...
Recreational Fishing ... Other devices, commonly referred to as terminal tackle, are also used to affect or complement the presentation of the bait to the targeted fish...
Vision In Fishes ... The ratio of rods to cones depends on the ecology of the fish species concerned, e.g., those mainly active during the day in clear waters will have more cones than those living in low light environments...
Fish (food) ... The modern English word for fish comes from the Old English fisc (plural: fiscas) which was pronounced as it is today... There are issues with fish contaminated with heavy metals such as mercury and lead, or by toxic chemicals such as those containing chlorine or bromine, dioxins or PCBs... Mercury Fish products have been shown to contain varying amounts of heavy metals, particularly mercury and fat-soluble pollutants from water pollution...
Fish Diseases And Parasites ... Specific defences are specialised responses to particular pathogens recognised by the fish's body, that is adaptative immune responses. In recent years, vaccines have become widely used in aquaculture and ornamental fish, for example vaccines for furunculosis in farmed salmon and koi herpes virus in koi...
Mercury In Fish ... The presence of mercury in fish can be a health issue, particularly for women who are or may become pregnant, nursing mothers, and young children... This results in the bioaccumulation of mercury, in a buildup in the adipose tissue of successive trophic levels: zooplankton, small nekton, larger fish etc... Anything which eats these fish within the food chain also consumes the higher level of mercury the fish have accumulated...
Fishing Industry ... The commercial activity is aimed at the delivery of fish and other seafood products for human consumption or as input factors in other industrial processes... Commercial sector The commercial sector of the fishing industry comprises the following chain: Commercial fishing and fish farming which produce the fish Fish processing which produce the fish products Marketing of the fish products World production Fish are harvested by commercial fishing and aquaculture... According to the Food and Agriculture Organization (FAO), the world harvest in 2005 consisted of 93.3 million tonnes captured by commercial fishing in wild fisheries, plus 48.1 million tonnes produced by fish farms...
Shoaling And Schooling ... Fish derive many benefits from shoaling behaviour including defence against predators (through better predator detection and by diluting the chance of individual capture), enhanced foraging success, and higher success in finding a mate...
Diversity Of Fish ... Unlike groupings such as birds or mammals, fish are not a single clade but a paraphyletic collection of taxa, including jawless, cartilaginous and skeletal types... Lampreys attached to a lake trout Mouth of a sea lamprey Pacific hagfish resting on bottom at 280 m Stir-fried hagfish, from Korean cuisine Cartilaginous fish Cartilaginous fish have a cartilaginous skeleton... Because cartilaginous fish do not have bone marrow, the spleen and special tissue around the gonads produces red blood cells...
Aquaculture ... The reported output from global aquaculture operations would supply one half of the fish and shellfish that is directly consumed by humans; however, there are issues about the reliability of the reported figures... Further, in current aquaculture practice, products from several pounds of wild fish are used to produce one pound of a piscivorous fish like salmon... Particular kinds of aquaculture include fish farming, shrimp farming, oyster farming, algaculture (such as seaweed farming), and the cultivation of ornamental fish...
World Fish Production ... The number of individual fish caught in the wild has been estimated at 0.97-2.7 trillion per year (not counting fish farms or marine invertebrates)... Marine and inland fisheries World capture production 2007 in thousands of tonnes Inland fisheries Marine fisheries Totals Freshwater fish 8,695 23 8,718 Diadromous fish 341 1,444 1,785 Marine fishes 82 65,627 65,709 Crustaceans 474 5,367 5,840 Molluscs 383 7,182 7,564 Other 61 388 449 Totals 10,035 80,029 90,064 Capture production by species The following table shows the capture production by groups of species (fish, crustaceans, molluscs, etc) in tonnes... Capture production by groups of species in tonnes Type Group 1999 2000 2001 2002 2003 2004 2005 freshwater fish Carps, barbels and other cyprinids 616 828 574 405 569 934 616 985 624 333 594 392 648 160 freshwater fish Tilapias and other cichlids 636 758 680 004...
Cat ... Cats are similar in anatomy to the other felids, with strong, flexible bodies, quick reflexes, sharp retractable claws, and teeth adapted to killing small prey. As crepuscular predators, cats use their acute hearing and ability to see in near darkness to locate prey...
Pet ... In many locations, animals that are considered pets by their owners but are legally classified as livestock, including horses, pigs, camelids, and fowl may be banned from being kept within the city limits or restricted to property of a certain larger size. The cities of Berkeley, California, and Boulder, Colorado, have passed laws stating that people who have pets do not "own" them; rather, they are the pet's "guardian."...
Disease In Ornamental Fish ... Due to their generally small size and the low cost of replacing diseased or dead fish, the cost of testing and treating diseases is often seen as more trouble than the value of the fish... Issues in diagnosis and treatment Due to the artificially limited volume of water and high concentration of fish in most aquarium tanks, communicable diseases often affect most or all fish in a tank... An improper nitrogen cycle, inappropriate aquarium plants and potentially harmful freshwater invertebrates can directly harm or add to the stresses on ornamental fish in a tank...