The Picturesque World of Fish

Welcome to the beautiful, the amazing, the truly surprising world of fish

Fish are amazing animals, they are extremely diverse in shape, color and habit, far more so than any other vertebrates. Fish are easily the most successful of the vertebrates. I hope that in reading these pages you will come to understand, admire, respect and even love the beautiful, Fabulous Fish

When you realise that an incredible 72 percent (nearly 3/4s) of the worlds surface is covered with water. That water, as a medium, is 800 times denser than air, meaning its supports your body a lot better than air does. And finally that water is the home of, and the basis for all life. It seems obvious that living in water is a good thing to do. Which is exactly what fish do.

More Fish

Yes it is true, in terms of numbers of individuals and in terms of numbers of species, fish out compete all the other vertebrates easily. There are about 29,200 species of fish known to science (February 2006)and we are still counting.

Hundreds of new species are described every year. This means there are about as many species of fish as there are species of amphibians, birds, mammals and reptiles all added together.

Most fish live in the shallow waters of the continental shelves. The continental shelves make up less than one twentieth of the surface of the oceans, yet the greatest diversity of fish live there. The sea floor of the continental shelf is the most diverse of all marine habits. Unfortunately it is also the most often polluted, and most easily damaged by bad fishing techniques.

Our Distant Ancestors

Somewhere in the dim dim history of our evolution is a species is a fish, or something like a fish. Fish were the original vertebrates, they first appeared about 500 million years ago as far as we know, long before the reptiles, mammals and the birds. During this time they have evolved into a myriad of different forms and learned to survive using a huge variety of behaviours

Unfortunately fish are often hard to see, they live beneath surface of the life giving waters of this planet, and this means they are not nearly as well known as they should. So please enjoy the rest of these pages and perhaps say thank you to the next fish you eat for giving up its life for you.

Some Amazing Fish Facts

There are about 30,100 species of fish divided up into 59 orders, 490 families and 4,300 genera as off January 2008, however science has been naming new species at the rate of about 200 or more a year over the last decade.

Bony Fishes (Osteichthyes) have far less weight of bones and far more weight of muscles in their bodies than either Birds or Mammals (fish average 40% to 65% muscle), this makes them extremely good value food on a pound per pound basis.

Fish live everywhere, from the surface of many waters to the bottom of the deepest oceans, from the nearly frozen waters of the poles (about 200 species) to the hot springs with water temperatures as high as 39o C (100o F). Three hundred species of fish live their lives permanently so deep below the surface of the sea (more than 1,000 metres down) they never see the light of the sun.

Fish like warm water, the closer you get to the tropics the greater the diversity of fish species you will find. About 40% of all fish species live in freshwaters. More than 700 species of fish are known to be in danger of becoming extinct. In reality the number is probably much larger, but in many parts of the world we have little or no information on the state of any fish populations. In the USA, one of the best surveyed countries in the world 120 species are registered as threatened.

Some fish go in sex change as a natural part of their lives. Fishes such as Wrasses and Parrotfishes are all born female, with only a few individuals becoming male later in their life. Contrariwise Clownfishes are all born male, later when the existing female/s die/s the most dominant male/s become/s female.

The Molly (Poecilia formosa) exists as an entirely female species, reproduction is by means of parthenogenetic clones. However, in order to stimulate the reproductive process, these female Mollies need to mate with a male, obviously one of a different species as there are no male Mollies.

Some Champion Fish

The first Fish was:-Science now generally recognises the Conodontia as the first true fish, their fossil remains reach back as far as 515 million years ago and they looked like small Hagfish (less than 7cm or 3.5 in long). However in 2001 two chinese scientists described two new species of possible vertebrates from strata dated to 530 MYA, these two organisms Myllokumingia fengjiaoa and Haikouichthys ercaicunensis appear to be related to early Lampreys and may in time be proven to be the earliest known fish.

The largest fish ever is :-The largest ever fish was a shark as far as we know, but not the whale Shark of our modern seas. Instead the title must go to a giant relative of the Great White Shark called the Megalodon Shark or Megatooth Shark (Carcharodon megalodon). This truly impressive carnivore, now known only from the fossil record of its teeth probably lived between about 20 to 2 million years ago. A modern estimate of its size, based on reconstruction of the jaw and comparison with todays Great White Shark suggest it probably was about 14.7 m (48.4 feet) long and weighed in at around 35,000 kg (77,092 lbs).

The smallest fish is :- By smallest here I mean shortest as an adult, obviously newly hatched fry can be much smaller than the dimensions recorded here. Three species of fish are reported at Fishbase to have lengths of 1 cm. Pamphorichthys minor, Photocorynus spiniceps and Trimmatom nanus. However in the Guinness Book of Animal Records T. nanus is recorded as having an average length of 0.86 cm for males and 0.89 cm for females, quite where the confusion comes from here I do not know, both these organisations work hard to get their figures correct.
To answer our question it really doesn't matter because there are now still two other species known to science that are even smaller than T. nanus even at the shorter Guinness Book of Animal Records length. The larger of these is Australian Matsubarichthys inusitatus which just scrapes past T. nanus at 0.84 cm in length. However as only one specimen of this fish has ever been caught we don't know what the average size of the species is.
Until recently the smallest known fish to science was the Plainchin dreamarm, Leptacanthichthys gracilispinis. This is a type of angler fish found off the coast of Canada, it has an average length of 0.8 cm or just one third of an inch.


News Update.
In January 2006 scientists announced the discovery of a new genus of fish with at least one, as of yet undescribed species, that is now the smallest know fish on record. Scientists reported in a journal published by the UK's Royal Society that individuals of the Paedocypris genus can be just 7.9mm long at maturity. Unfortunately they also report that these fish, which were found in the peat swamps of the Indonesian island of Sumatra already threatened with habitat loss and that other similar species may be lost even before we get to know of them.

The tastiest :-This is obviously a matter of choice and cannot be scientifically verified, also the cooking method and expertise is very important. So this is a question you have to answer for yourself. Some common answers are :- Catfish. Rainbow Trout, Salmon, Sea Bass, Snapper and Trigger Fish, but many other species of fish are excellent eating as well.

The smartest fish is :- again nobody knows for sure because very few studies have been done comparing, or attempting to measure the intelligence of fish. However recent data suggests that many fish are more intelligent that was once supposed. Over 500 studies of fish intelligence have revealed some remarkable things, to learn more visit the page on learning and intelligence in fish.
The best we can do is look at the physical dimensions of a fish's brain. We cannot just look for the biggest brain, because naturally bigger animals have larger brains, yet nobody would suggest a cow was smarter than a dog. Two parametres that can help us assess a fish's intelligence are the relative brain weight to body weight and the complexity of the brain. I have found no information comparing the brains of fish in terms of complexity, or surface area (foldedness). This leaves us with the brain to body weight relationship. The winner in this category is the Elephantnose fish (Gnathonemus petersii) which has a brain that amounts to 3.1% of its total body weight. To put this into perspective most fish have brains that weigh less than 1% of their total body weight and even the human brain only averages out at 2.3% of body weight. Whether this makes it the world's most intelligent fish however I cannot say.
The Elephantnose fish is a tropical, freshwater fish from Central Africa that grows to a maximum length of 35 cm (14 ins). It is a species that is commercially available to aquarists and it is known for its playful behavior. It also seems to have a strange karma because not only is it incorrectly named, it is its chin not its nose, that is enlarged, but it is also spelled incorrectly (in terms of its scientific name) in at least 3 major works on fish that I have looked at, including a university level textbook.

The dumbest fish is :- yet again we cannot be sure, but what we do know is that Acanthonus armatus, a deep sea Cusp Eel, has the smallest brain, relative to body size, of any fish, or even of any vertebrate.

The fastest fish is :-Finding accurate data on the fastest fish in the world has been difficult because actually measuring the speed of these formula one fish is itself very difficult. Nevertheless it seems that there are two species of fish that would be pulled over by the police if the were swimming flat out down the highway here in Greece. The slower of these is the Cosmopolitan Sailfish, Istiophorus platypterus which was recorded to take out 91 metres (300 feet) of line in three seconds, which is the equivalent of 109.2 km/h or 72 mph. However swimming up the wing of a fishy football field this champion would be left standing by a top notch Black Marlin, Makaira indica, which has apparently been timed at 130 km/h or 86.7 mph. Ref.= Block, B.A., D. Booth and F.G. Carey, 1992.

The fish that lays the most eggs is :-The Grey Grouper, Epinephelus tauvina a female of which may lay as many as 340 million eggs in a single season, however the eggs are very small, being around 0.75mm in diametre.

The fish that produces the least eggs or young is :-The prize here is shared between at least three members of the genus Mobula, more commonly known as Devil Rays, i.e. Mobula tarapacana the Chilean devil ray, Mobula japanica the Spinetail mobula, and Mobula thurstoni  the Smooth-tailed Mobula. Each of these produces only one egg, and subsequently only one young per season, these young are born alive and never know the open water as an egg. There are several other members of the genus Mobula but their reproductive biology is poorly known.

The most valuable fish in the world is :-The most expensive fish dish in the world is caviar, which is basically fish eggs in wine or vinegar and a little salt. The best caviar comes from Sturgeons, in particular the Russian Sturgeon (Huso huso). Sturgeon are large fish, although the average size of specimens caught now is much less than it was 50 years ago, nevertheless one female can produce a lot of caviar. The record is for a female caught in 1924 in the River Sosna a few hundred kilometres south of Moscow. This specimen weighed in at 1227 kg (2706 lb) and produced 245 kg (540 lb) of best quality caviar. On today's market this would be worth about $200,000.00 US dollars.

The most shocking fish in the world is :- Many species of fish have learned to use electricity for communication, for echolocation, for defence and even for hunting. Most of these are harmless, but the Electric Eel (Electrophorus electricus)from South America is the king of living generators and therefore the most shocking fish on earth. The electric organs can occupy as much as 80% of the animals body and an average specimen can deliver 1 amp at 400 volts. The record is held be a specimen from the New York Aquarium which was measured delivering a pulse of 650 volts in the 1930s. This voltage would easily kill an adult human.

The most poisonous fish in the world is :- Poisonous means something makes you ill if you eat it, animals which inject toxins when biting or stinging are called venomous. Many fish are poisonous to one degree or another, the most notorious of these are in the family Tetraodontidae, otherwise known as Puffer fish. Of these the world record holder for poisonousness is the Death Puffer of Maki-maki Arothron hispidus. The internal organs of this fish are so poisonous that it takes less than 0.1 grams (or 400ths of an ounce) to kill an adult human being in less than half an hour. Nevertheless people in Japan eat the flesh of this fish which can be consumed safely if it is prepared in such a manner that none of the tetrodotoxin in the organs or the skin gets into the flesh. The meal is considered a delicacy and the chefs who prepare the meal serve a special three year apprenticeship. Despite all precautions however about 50 people die every year in Japan from eating poorly prepared fish.

The most venomous fish in the world is:- Fish evolved venoms most probably as a means of defence not of attack. There venoms therefore tend to be painful rather than fatal. Also, as with the poisonous fish described above, these toxins evolved to protect them from aquatic predators, their effect on humans is not particularly important from the fish's point of view. At least 10 families and forty species of fish have evolved toxins that can be injected into another animal using specially adapted spines. The most dangerous of these are the Stonefish of the family Synanceidae. The family contains four species, the most dangerous of which is the Indian Stonefish, Synanceia horrida. This species, which can grow to 60 cm (24 ins) in length has thirteen dorsal spines each connected to its own venom gland. The fish lives by lying in wait on the sea floor and catching passing prey. When frightened it erects its spines. Most injuries occur as a result of the fish being stepped on. The spines are so sharp they pass through a beach shoe. Most injuries are not fatal, although some are, however they are always extremely painful.

The amount of fish caught every year is variable:- On August the 11th 1987 a fishing trawler from Iceland called Videy unloaded 37,897 tonnes (1 tonne = 1,000 kg) of fish at the port of Hull in the UK. This was until the late 1990s, and may still be, the largest tonnage of fish ever caught by a single trawler in a one trip. Although most trawlers catch far less than his on an average trip, there are many thousands of trawlers in the world and you can easily see that the number of fish caught every year is huge. In 1991 China alone, as the worlds leading fishing nation, caught 13.13 million tonnes of fish. Although this is obviously a huge number of fish it still only works out at about 12 kg of fish per person per year for China. The United Nations Food and Agriculture Organisation data shows that 96.92 million tones of fish were caught in 1991. During the 1990s the number of fish caught varied between 85 and 96 million tonnes. However the total number of fish sold continued to rise and reached 126 million tonnes in 1999. The difference is made up in the form of aquaculture or farmed fish.

The most fish caught in a single net is :- On August the 28th 1986 the fishing trawler M/S Flomann from Hareide in Norway caught 2,471 tonnes of fish in a single throw of a purse seine-net. This many fish were not counted individually, but an estimate made at the time suggests there were more than 120 million fish in this single catch.

The largest fish ever caught on a rod is :- The Great White Shark (Charcharodon charcharias). A specimen caught by Clive Green on the 26th of April off Albany South Australia weighed in at 1,537 kg or 3,388 lb.

The fish with the most limited distribution is :- The Devils Hole Pupfish, (Cyprinodon diabolis), a small, 15 to 20 mm in length, cyprynid type fish is found only in a single location, called Devil's Hole in Nevada USA. The entire extent of the fish's normal habit is about 20 m2 and the population ranges between a mere 200 to 700 individuals.

The most abundant fish in the world is? :-This is another unanswerable question, because we just don't have any way of counting the fish, especially those we don't eat. What we can say is that the most abundant fish that is commercially caught is the Peruvian Anchoveta, Engraulis ringens. This is a small fish, up to 8 cms long which is caught by the millions of tons off the Coasts of South America. However in the 1970s overfishing, combined with environmental factors caused a crash in the abundance of Anchoveta. Since then the populations have recovered somewhat, but still show considerably yearly variations. Another candiate might be Menhaden but I have not yet been able to track down accurate data on the numbers caught, and this species too is suffering large reductions in population size due to over fishing.

The longest lived fish is :-As animals go human beings are pretty long lived, and on average there a few species that do better than we do in terms of years, among these there are number that live in the water, in fact the oldest animal on the planet is a whale which some scientists think can reach ages in excess of 200 years. However there are also several species of fish that are scientifically reported to have individuals that have lived longer than any human. Two of these are; 1) celebrating 140 birthdays is the Warty Oreo Allocyttus verrucosus, and 2) the Shortraker Rockfish Sebastes borealis which is recorded as living for 157 years. However the current record holder is a Rougheye Rockfish (Sebastes aleutianus) from Alaska which was reported to be 205 years old in 2002 at which time it was still living.

The fish with the largest egg is :-This is a question that is still really unanswered as information is lacking for many species.
However amongst the sharks and rays the largest egg case that is laid belongs to the Big Skate (Raja binoculata). These egg-cases can be 30 cm long and 19.5 cm wide. However they generally contain more than one egg or embryo, so this is a bit of a cheat.
The largest fish egg known to science in the strictest sense of the word is the egg of the Coelocanth (Latimeria chalumnae) which is round and a diametre of between 9 cm and 7.5 cm and can weigh as much as 325 grams or 11.6 ounces. This is not large by the standards of terrestrial animals, but remember fish eggs do not need to contain all the developing embryo's water as bird's eggs do.

The deepest living fish is :- Abyssobrotula galatheae, it has been collected at a depth of 8372 metres in the Puetorican Trench, very little is known about its biology.





Some Basic Language

Benthic = Living on the floor of the sea, ocean etc .
Pelagic = Living swimming in the open waters of the sea, ocean etc.
Epi = Near the surface, 0 to 150 metres.
Meso = 150 to 1,000 metres in depth (Middle sea).
Bathy = 1,000 to 3,000 metres in depth (Deep Sea).
Abysso = 3,000 to 6,000 metres in depth (Bottomless Sea).
Hadal = 6,000 to 11,000 metres in depth (Unseen Sea).
So an Epipelagic species lives in the open waters of the sea between 0 and 150 metres in depth.
Or a Bathybenthic species lives on the sea-floor between 1,000 and 3,000 metres in depth.

The Fish Anatomy Menu
Anatomy Fins Blood Nerves Magnetism Swim-bladder
Skeleton Sight Scales Hearing Electricity Osmoregulation
Digestion Gills Smell Muscles Lateral Line Thermoregulation



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