Causes and Solutions of Frequent Aquarium Fish Deaths

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...

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...

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...

Fish Farming ... There is an increasing demand for fish and fish protein, which has resulted in widespread overfishing in wild fisheries... However, farming carnivorous fish, such as salmon, does not always reduce pressure on wild fisheries, since carnivorous farmed fish are usually fed fishmeal and fish oil extracted from wild forage fish... The global returns for fish farming recorded by the FAO in 2008 totalled 33.8 million tonnes worth about $US 60 billion...

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...

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...

Bird Vision ... Birds, unlike us but like fish, amphibians and reptiles, have four types of colour receptors in the eye. These give birds the ability to perceive not only the visible range but also the ultraviolet part of the spectrum, and other adaptations allow for the detection of polarised light or magnetic fields...

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...

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...

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...

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...

Angling ... In many parts of the world, size limits apply to certain species, meaning fish below and/or above a certain size must, by law, be released... Among the many species of salt water fish that are caught for sport are swordfish, marlin, tuna, salmon and halibut... In Europe a large number of anglers fish for species such as carp, pike, tench, rudd, roach, European perch and barbel (especially in stillwaters)...

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."...

Sustainable Seafood ... Nonprofit groups addressing seafood sustainability include the Marine Stewardship Council, Monterey Bay Aquarium, Oceana, John G. Shedd Aquarium and Greenpeace...

Bird ... Modern birds are characterised by feathers, a beak with no teeth, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a lightweight but strong skeleton. All living species of birds have wings—the now extinct flightless moa of New Zealand were the only exception...

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...

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...

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...

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...

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...

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...

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...

Fish ... Commercial and subsistence fishers hunt fish in wild fisheries (see fishing) or farm them in ponds or in cages in the ocean (see aquaculture)... Fish have had a role in culture through the ages, serving as deities, religious symbols, and as the subjects of art, books and movies...