Thursday, August 23, 2012

Angel fish

Pterophyllum is a genus of freshwater fish from the Cichlidae family more commonly known as angelfish. All angelfish species actually originate from the Amazon River, Essequibo River, and Orinoco River basins in South America. There are 3 Pterophyllum species which are known for being laterally compressed round bodies and elongated triangular anal and dorsal fins. They are naturally striped which provides this fish with camouflage.
2751226374 8063b20f88 Angelfish
A colourful angelfish
Angelfish are ambush predators that prey on macroinvertebrates and small fish. All angelfish species form monogamous pairs. They lay eggs on a flattened leaf or a submerged log and care for their brood.
Pterophyllum scalare was the first freshwater angelfish that was talked about in 1824. It was described by Lichtenstein. In 1906, Pellegrin discovered the Pterophyllum altum. In 1963, another species of Pterophyllum was discovered, called P. leopoldi. This was described by Gosse as an angelfish as they were first described under a different name.
Pterophyllum altum are also known as altum angelfish, deep angelfish, or Orinoco angelfish. They still can be found in the wild strictly in the Orinoco River Basin and the Upper Rio Negro watershed in Venezuela, Colombia, and Brazil. This species is the largest of the Pterophyllum genus, and specimens exceed over 50 cm in height in the wild. However, aquarium specimens are known to grow up to 40 cm. Its is silver coloured, with 3 brown or red vertical stripes. It also has red striations on the fins. It may have red spots and a bluish green overcast when it matures. When it is aroused, it shows a black operculum spot. This fish is the national fish of Venezula and appears on some Venezuelan currency notes.
The Pterophyllum leopoldi is also known as the dwarf angelfish, long-nosed angelfish, teardrop angelfish, or the Roman-nosed angelfish. It originates from the Amazon River basin. Unlike other Pterophyllums, it does not have a pre-dorsal notch. It is the smallest of the angelfish species and is also the most aggressive one.
Pterophyllum scalare is the most common angelfish, and is commonly referred to just as “angelfish” or “freshwater angelfish”. It is the most common species in captivity, but its natural habitat is in the Amazon River basin, the rivers of Amapa in Brazil, the Oyapock River in French Guiana, and the Essequibo River in Guyana. It is found in swamps or flooded ground where vegetation is dense.
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A Pterophyllum scalare in captivity
In the late 1920s and early 1930s, angelfish were bred in captivity in the USA. They are currently one of the most commonly kept freshwater aquarium fish which are prized for their unique shape, colour, and behaviour. It is an intelligent fish as they are able to recognise their owners. The most commonly kept Pterophyllum species that is kept in household aquariums is the P. scalare. P. leopoldi is the hardest to find.
Angelfish should be kept in a warm aquarium that has a temperature of about 27 °C. They should be fed a mixture of live, frozen, and flake foods. Owners should make sure not to overfeed them, as angelfish will continue to eat even if they don’t need to. If they are overfed, fats will build up resulting in inactivity and they will die an early death. Angelfish will keep well in an acidic environment, with a pH level of 7.0.
Although angelfish are generally peaceful, the general rule is that big fish will eat little fish. Aggressive fish should not be kept with the angelfish because their flowing fins are vulnerable to fin nipping. Even some small but aggressive fish will nip at the angelfish’s fins. Freshwater angelfish are placed in the semi-aggressive category in most pet stores. Platies, tetras, and plecos are compatible with angelfish. However, some tetras will nip at the angelfish’s fins.

An Antarctic Toothfish

Also known as the Antarctic toothfish, the Antarctic cod is famous for many reasons. One of which, is that its name is actually a misnomer as it actually is not even related to a cod, as it is not even in the same order. In fact, it it is more closely related to the Patagonian toothfish, which it is sometimes confused with.
Antarctic toothfish full size landscape e1284454280192 Antarctic Cod
An Antarctic Toothfish
The other reason it is famous is because it produces an antifreeze called glycoprotein, which allows it to survive in the freezing, ice-laden waters of the Southern Ocean around Antarctica. It has a heartbeat once every 6 seconds, and it is hoped that research into these fish will lead to medical advances in cardiac medicine where human heart beats are slow during particular medical procedures, or if the heart fails to beat fast enough due to hypothermia.
The Antarctic cod are a large, silver-brown coloured fish that has been caught in waters that are deper than 2,000 metres. When they are fully grown adults, they are among one of the biggest in the Antarctic continent as they can reach more than 2 metres long and weigh over 135 kg. This was recorded in the Ross Sea, by researchers from New Zealand.
Antarctic cod have a lightweight, cartilaginous skeleton. They have fatty deposits which are a stored energy sauce, and lack a swim bladder. They also have retinas which are adapted to low lighting levels.
The flesh of this fish is white, and has a high oil content. The taste is similar to a cod, which is why this species is sometimes called the Antarctic Cod. Data collected during a CCALMR tagging programme in the Ross Sea indicates that this fish is quite fast growing. Within 5 years, they reach 60 cm, in 10 years they reach 1 metre, and in 20 years they reach 1.5 metres. The maximum recorded age so far is 48 years, with a weight of 150 kg. However, there are only a few fish that have been caught by the fishing industry that are about 30 years old. Research has found that this fish matures at 10 years old.
Large Antarctic toothfish full size landscape e1284454342851 Antarctic Cod
Scientists with a 1.5m Antarctic Toothfish
The Antarctic Cod is a fish eater. However, they are known to eat pretty much any of the remains of penguins caught by orca and seals on the surface. Studies show that this fish occupies a similar trophic level such as Orca, Weddel seals, bluefin tuna, and sperm whales. As a result, it is thought that small juvenile Antarctic Cod may be prey of the Orca, large squid, leopard seal, and the Weddell seal.
This fish is managed by CCALMR (Convention for the Conservation of Antarctic Marine Living Resources). CCALMR has enforced limited fishing to a precautionary catch level in the Ross Sea, to effectively manage this fish for the future. This also means that they can sufficiently collect more biological and stock size information for scientific purposes. Greenpeace International has also added the Antarctic Cod to its seafood red list in 2010, as they are commonly sold in supermarkets and could be sourced from unsustainable fisheries.

Porcupinefish

Porcupinefish are part of a family of fish that are called Diodontidae, and are quite often more commonly called the pufferfish, or the blow fish.
  Porcupine Fish
Inflated Porcupine Fish
They are not in reality pufferfish, but are related to them. The Porcupine fish sports on its body a wide array of spines that stand erect when the fish inflates and are very often mistaken for pufferfish.
The Porcupine fish has the unique ability of being a fish that can blow up their bodies, or inflate them. They do this by swallowing air or water and will become literally as rounds as a basket ball.
The porcupine fish can enlarge himself almost double the size that he was. Scientists think this is another method of self defense for the porcupine fish.He does this to lower the predators who can prey on him to about half what they normally would be if he did not have this ability.
His second and probably best defense is that he bears many rows of
porcupinefish  Porcupine Fish
Uninflated porcupinefish
very sharp spines, and when the porcupinefish blows himself up to full volume, they become erect, and stand straight up and out.
Some species of Porcupine fish also bear a venom, or poison that is emitted from the spines. They have what is called a Tetrodoxin within the skin as well as or in addition to in their intestines.
As a result of their great methods of self defense the porcupine fish has very few predators that will take them for food.
Adult porcupinefish are sometimes a meal for larger fish such as the shark and the Orca, or whale, although this is only rare in occurence.
The younger or juvenile porcupine fish may sometimes be taken and eaten by larger tuna or by dolphins.

Bob Fish

The Blob fish is a type of fish found off the coast of Australia and Tasmania but don’t expect to see one on your holidays as they are extremely rare to come by. The reason the Blob fish is so rare is that they live very deep down in the sea, literally just off of the sea bed. The Blob fish are found at a depth of around 800 meters which would make life impossible for most fish as at that depth the pressure is roughly eighty times more than at sea level. The reason that the Blob fish can survive at such a depth is also what gives it such a unique look (some would say ugly), foregoing a gas bladder (found in most fish to keep them buoyant) the Blob fish is almost entirely comprised of gelatinous substance, this keeps the Blob fish from sinking as the density of the goo is less than that of then sea where they are found.
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Blob fish out of water
As the Blob fish is comprised of a gelatinous substance they actually have no muscles at all and they just float in the same spot most of the time waiting for their next meal. Scientific research has explained that the main diet of the Blob fish is that of sea urchins and mollusks. The Blob fish will literally float in place waiting for a meal to come by with little or no effort exerted in hunting prey, this leads to  in-frequent meals which works fine for the Blob fish as sustenance isn’t needed in a large level as the Blob fish devotes almost of its time to floating stationary, its because of this behavior that the Blob fish has been branded ‘lazy’.
The female Blob fish lays thousands of eggs at once and unlike a lot of fish the Blob fish will actually stay with her eggs, floating above as usual of in some cases literally sitting on the eggs. The Blob fish nesting habits are interesting as its not uncommon to find groups of Blob fish nesting together with one females eggs sometimes right next to another females. Its not known whether this behavior is strategic of whether it is just a result of their ‘lazy’ nature.
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Blob fish underwater
When under water the Blob fish has an comical, almost human looking face however if taken out of water the Blob fish will die after a short while and is gelatinous body will dry out and shrivel no longer resembling the typical way people think of Blob fish. Currently the survivability of Blob fish is being investigated as it is becoming to common an occurrence of fishermen catching Blob fish by mistake and of course severely lessening their chances of survival.

Oscar Cichlid

The Cichlidae family of fishes, commonly known as cichlids, is a diverse and extensive group of fishes. Scientists are still learning and working to categorize all of the species within the Cichlidae family. There may be thousands of known species of cichlids, with equally varying natural habitats. Even the most common cichlids found in aquariums come from all over the world.

  1. Oscar Cichlid (Astronotus ocellatus)

    • Oscars are found in the Amazon basin waterways. They are well-adapted to muddy waters with temperatures from 71 to 77 degrees F.

    Kribensis (Pelvicachromis pulcher)

    • Also known as the Niger cichlid or the purple cichlid, the kribensis is native to Nigeria and Cameroon. They live in waters with lots of vegetation and caves in which to breed.

    Electric Yellow Cichlid (Labidochromis caeruleus)

    • This cichlid is one of the many that reside in Lake Malawi in southeastern Africa. They stay in areas of the lake that have a lot of sediment and rock outcroppings.

    Convict Cichlid (Archocentrus nigrofasciatus)

    • Convict cichlids are found in the fresh waters of Nicaragua and Costa Rica. They prefer to live in waters that are warm, up to 80 degrees F, and where there is fine sediment in which to breed.

    Jack Dempsey Cichlid (Cichlasoma octofasciatum)

    • The natural range of the Jack Dempsey cichlid is from southern Mexico to throughout Central America. They also live in warm waters around 80 degrees F, and they like to hide in caves.


The Natural Habitat of the Oscar Cichlid

  1. Temperature

    • The Oscar Cichlid prefers slow moving, fresh water habitats. It protects itself by hiding under branches and trees that have sunk to the bottom of the river bed. The Oscar cannot tolerate cool water temperatures and will die if the temperature gets below 55 degrees Fahrenheit or 12 degrees Celsius.

    Food

    • Bunocephalus catfish is a favorite Oscar Cichlid food.
      Oscar Cichlid's eat slow moving fish in its natural habitat. The favorite foods of the Oscar are catfish such as Bunocephalus, insects, insect larvae, and crustaceans. The Oscar Cichlid captures its prey by using a suction method, often laying on its side to imitate death so its prey will move close enough to get caught in its suction. Vitamin C is an important need of the Oscar Cichlid in its natural habitat. Without enough of this vitamin, disease and death will occur.

    Breeding

    • Baby Oscar Cichlid
      Oscar Cichlids remain in heavily vegetated areas near the banks of the river for breeding and nesting. They tend to breed more frequently during rainy seasons. Oscars are very territorial during the spawning period and will fiercely defend their territory. The female Oscar lays from one thousand to three thousand eggs during spawning on a flat, clear substrate surface. The Oscar Cichlid eggs hatch within four days.
      The female Oscar will protect the newborn fish in her mouth if a predator is nearby. The newly hatched Oscars grow quickly and will reach an adult size of up to two feet with an oval, stocky body, large eyes and head and a large mouth. The Oscar Cichlids reach sexual maturity in about one year and breed for about ten years.

    Predators

    • Dorsal fin(3), caudal peduncle(5)
      Oscar Cichlids confuse their predators by changing their color, similar to a chameleon, which naturally camouflages the Oscar, blending with the colors of the riverbed and vegetation. The Oscar Cichlid also has ocelli which are spots that resemble eyes on the dorsal fin and caudal peduncle. These false eyes deter nipping of the fins by attacking piranha. Oscars are normally slow fish but can swim very quickly for a short distance in an attempt to flee from a predator. The predators of the Oscar Cichlid found in its natural habitat include other large fish, invertebrates, reptiles, and large birds.

    Fishing

    • The Oscar Cichlid is caught in its natural habitat by fishermen who sell them to supermarkets and restaurants. The oscars make excellent fish food when full grown.
      Oscars are also captured in their natural habitat to use as aquarium fish. The oscars are very popular tank fish and are a favorite of aquarists. The Oscar Cichlid is hardy,

Oscar Fish in Natural Habitat

The oscar, originally described by Louis Agassiz in 1831, in a member of the cichlid family native to the rivers of South America. The oscar is also commonly known as the velvet cichlid, red oscar, tiger oscar and marble cichlid in addition to a number of local names in given to it by the people of South America. In areas where there is a large native oscar population, the fish are commonly sold in meat markets but they have not found popularity in the global market because of slow growth.


funny pic