Manta Ray

The manta ray is a large species of flattened fish, closely related to other cartilaginous fish such as sharks. The manta ray is the largest species of ray in the world with some manta ray individuals reaching up to 9 meters wide.

The manta ray is most commonly found in the warmer, tropical of waters of the world's oceans, typically around coral reefs and along the continental shelves where food is in abundance. However, due to their enormous size, manta rays are also commonly spotted hunting out in the open ocean.

The manta ray is a solitary animal and is also a graceful swimmer. Like other large species of fish, manta rays swim by moving their pectoral fins up and down which propels their enormous body through the surrounding water. The short tail of the manta ray also allows the manta ray to be more acrobatic with it's movement, and they have even be seen leaping out of the water.

Manta rays are known to frequently visit cleaning stations where small fish such as wrasse and angelfish swim in the manta ray's gills and over it's skin to feed, in the process cleaning it of parasites and dead tissue. Manta rays are generally not interested in eating these smaller fish as they are providing a great service to the manta ray.

Unlike many sharks, manta rays do not actually have teeth and instead sieve the food particles out of the water using rows of tiny plates in their mouths, which they funnel in their mouths as they swim. Manta rays eat tiny marine organisms including microscopic plankton, small fish and crustaceans.

Despite it's large size, the relatively docile nature of the manta ray means that it is actually preyed upon by a number of large marine predators. Large species of shark such as the great white shark, killer whales and also humans are known to hunt the manta ray.

After mating the female manta ray lays a couple of eggs which actually develop and then hatch inside her. This process is known as aplacental viviparity and is quite commonly seen in the reproduction of a number of shark and ray species. Within 6 weeks of hatching, the female manta ray gives birth to 1 or 2 manta ray pups, which develop into large adults fairly quickly.

Today, although the manta ray is not considered to be a species that is in imminent danger of extinction in the wild, the manta ray population numbers have been declining more quickly in recent years. Manta rays are particularly susceptible to pollution in the water and are quickly affected by overfishing in certain areas, and therefore a lack of food.

Electric Eel

Electric Eels are found in the waters of South America, and are capable of generating a 500volt electric shock through 28ft of still water. The shock that the electric eel produces is enough to harm any large mammal, including humans.

Electric eels can grow up to 2.5 metres and only need to surface for air every 10 minutes due to the eels complex circulatory system. Electric eels tend to live in muddy beds in calm water, eating fish and small mammals.

Despite the name electric eel, the electric eel is actually related most closely to a catfish and not the common eel fish and many electric eel adults tend to be smaller than their eel fish counterparts.

The electricity that the electric eel uses to shock its prey, is produced in pairs of organs that are found in the abdomen of the electric eel. These electricity producing organs take up around of 80% of the body of the electric eel leaving only 20% of the electric eels body free to hold the electric eels vital organs that it needs to survive.

Electric eels are found inhabiting fresh waters of the Amazon and Orinoco river basins in South America, and the electric eels tend to prefer the river floodplains, swamps, coastal plains, and creeks. Electric eels tend to live on muddy bottoms in calm water and in stagnant arms of rivers, where the electric eel spends most of its time hunting.

The electric eel is also known for its unusual breeding behaviour. In the dry season, a male electric eel makes a nest from his saliva into which the female electric eel lays her eggs. As many as 17,000 young electric eels will hatch from the eggs in one nest. These young electric eels feed mainly on invertebrates found on the river bed, however, first-born baby electric eels have been known to gobble up the eggs from batches of other electric eels that were laid only a short time after themselves.

Molly

The molly is a small-sized tropical fish that is found naturally in the warm and peaceful rivers of Central America. Today, mollies are extremely popular fish to be kept in the community of an artificial aquarium, all around the world.

Mollies are known for their calm and peaceful nature, which along with their brightly coloured bodies, makes them a particular popular choice for freshwater tanks of all shapes and sizes. The male mollies are more slender than the female mollies and have a slightly longer tail fin, making the two sexes easy to tell apart.

Mollies live amongst the plants in a group containing numerous molly individuals, known as a school. Although this works well for the mollies in the wild, the fast-paced breeding of these molly groups can quickly become a problem in artificial tanks.

Mollies are omnivorous animals and therefore have diet that is comprised of both plant and animal matter. Mollies primarily eat small invertebrates including insects and bloodworm, along with algae and food particles in the water.

Due to their small size, mollies have numerous natural predators within their environment, with larger fish being the most common predators of the molly. Aquatic birds and even reptiles are also known to hunt them.

Unlike many other species of tropical fish, female mollies give birth to live young rather than laying eggs which are very likely to be eaten. Mollies can give birth to up to 100 fry at once, only a couple of weeks after fertilisation occurred.

Piranha

The piranha is a type of freshwater fish found in the rivers of the South American jungles. The piranha can be found in nearly every country in South America and the piranha have been appearing more recently in the south of the USA.

The piranha fish has a single row of razor-sharp teeth with the piranha being most commonly known for their taste for blood. The piranha feeds on fish, mammals and birds alike, with the wholes group of piranhas feeding together in a slight frenzy.

Despite the carnivorous nature of the piranha, the piranha is actually an omnivore and will eat almost anything that it can find. Piranhas mainly feed on fish, snails, insects and aquatic plants occasionally eating larger mammals and birds that fall into the water.

Despite it's feared nature, the piranha actually has a number of predators in the wild, including humans that hunt the piranha for food. Piranhas are preyed upon by large predators such as river dolphins (known as botos), crocodiles, turtles, birds and larger fish.

The piranha is generally around 30cm long but some piranha individuals have been found measuring nearly 80cm. The piranha is said to be more feared by many humans than even a shark.

Piranhas are generally found in fast flowing rivers and streams where there is plenty of food for the piranha to eat. The piranhas lives together in large shoals and constantly compete for food. Feeding frenzies will be triggered when there is a shortage of food or blood in the water.

Piranhas tend to breed in pairs in slower water such as lagoons generally during the rainy season around April to May. The mating pair prepare a nest that the female piranha lays clusters of eggs in. The female piranha lays an average of 5,000 eggs and due to the fact that the male piranha and the female piranha defend their protected eggs so effectively, more than 90% often survive and hatch after just a few days.

In August 2009 a 35cm piranha was found in a river in Devon, thousands of miles from it's native home. The team that discovered the piranha were utterly bewildered as to what this tropical fish was going in a river in England but later deduced that this piranha must have been kept as a pet and then released due to the fact that it was eating sweetcorn.

Horn Shark

The horn shark is a small species of shark, natively found in the coastal waters of north-west North America. The horn shark is named for the broad, flattened head and high ridge found behind this shark's large eyes that is almost horn-like in appearance and makes this shark one of the hardiest of all shark species.

The horn shark is endemic to the Pacific north-east, and is only found in the warmer waters off the coast of California. The horn shark is most commonly found along the temperate to sub-tropical continental shelves where it spends most of it's time in search of hard-shelled marine organisms to eat off the sea-bed.

The horn shark is a small species of shark that typically measures about 1 meter in length. The horn shark can be most easily recognized by a short, blunt head with ridges over its eyes and two high dorsal fins with large venomous spines. The horn shark is usually a brown or grey colour with many small dark spots across it's body.

The horn shark is a clumsy swimmer that prefers to use its flexible, muscular pectoral fins to push itself along the bottom of the ocean rather than swimming through it. The horn shark is usually solitary, though small groups have been recorded (particularly during the mating season). During the day, horn sharks rest motionless, hidden inside caves or crevices, or within thick mats of algae, though they remain relatively alert and will swim away quickly if disturbed. After dusk, they roam actively above the reef in search of food.

Horn sharks are carnivorous predators and although they do eat fish and marine invertebrates on the ocean floor, around 95% of the horn shark's diet is made up of hard-shelled molluscs and crustaceans which they horn shark uses its short, hardened head to break them apart before eating the fleshy insides. Horn sharks also feed on echinoderms such as sea urchins and star fish.

Despite being quite complex predators themselves, the relatively small size of the horn shark means that they are by no means at the top of the food chain within their natural environment. Large species of fish prey on the horn shark along with other sharks that share their native range. Humans are also one of the horn shark biggest threat as although they are not really hunted, horn sharks are often caught as by-catch when we are fishing for other things.

Horn sharks tend to mate in between December and January with the female laying her eggs 4 to 5 months later. Female horn sharks can lay up to 24 eggs over a period of 2 weeks, which float in the ocean in a spiralled casing. The female horn shark is one of the only shark species to display pre-natal care, as she collects her eggs in her mouth before depositing them into the safety of crevices in the rocks. The horn shark pups usually hatch within a month.

Today, as so little is known about the horn shark population off the Californian coast, they have been listed as being Data Deficient as their is not enough information about their status in the wild. Like many other species however, the horn shark populations are being threatened both by water pollution and commercial fishing in the area.

Angelfish

There are around 100 different species of angelfish that inhabit the waters of the southern hemisphere. There are two main types of angelfish, those that live in the freshwater rivers in South America (freshwater angelfish) and those angelfish that inhabit the salty ocean waters (marine angelfish).

The freshwater angelfish has a more triangular shape and will generally only grow to a few inches in length. The marine angelfish can grow up to 12 inches (the same length as a big ruler) and generally have very brightly coloured markings but the exact colours depend on the angelfish species.

Both the freshwater angelfish and the marine angelfish are known to be relatively difficult fish to keep in household aquariums, as both types of angelfish require very specific water conditions. Angelfish are very susceptible to changes in the water such as salt levels and pH levels, and will often die if changes are too drastic.

Despite the fact that their names are the same, freshwater angelfish and marine angelfish are not thought to be closely related. The freshwater angelfish is a tropical species of cichlid, distantly related to the cichlids found in specific lakes in Africa. The marine angelfish are believed to be most closely related to the butterfly fish.

Freshwater angelfish are native to the Amazon basin and are also found in the rivers running off it. Freshwater angelfish inhabit the cleaner waters and prefer to be in temperatures between 25 and 30 degrees centigrade.

Freshwater angelfish lay between 100 and 1,000 eggs which hatch in just a couple of days. Freshwater angelfish tend to lay their eggs on a flat leaf or an underwater log. The baby angelfish (known as fry) remain attached to the eggs for another week and feed off the remaining yolk in the egg sack. When they are bigger at a week old, the angelfish fry detach from their eggs and become free swimming. It is at this stage that the baby angelfish begin feeding from nutrients in the water and on plants.

The triangular shape of the freshwater angelfish, means that the angelfish is able to hide more easily amongst the aquatic plants in the water. Wild freshwater angelfish have very distinctive dark stripes that run vertically down their bodies, giving the freshwater angelfish the ability to blend in to it\'s surroundings. Freshwater angelfish usually breed for life and it is often found that if one of the angelfish parents dies, then the remaining angelfish parent has no interest in breeding.

Freshwater angelfish feed on smaller fish and invertebrates in their natural environment as well as eating particles of food found in the water. The freshwater angelfish is preyed upon by larger species of fish, birds and marine mammals.

Marine angelfish are generally found in shallow reefs in depths of up to 50 meters. Marine angelfish are reported to be almost fearless and are noted to be inquisitive and curious towards divers. Some species of marine angelfish are solitary by nature where other species of angelfish form territorial mating pairs or even groups. The groups of marine angelfish usually have one male and a number of females.

Unlike the freshwater angelfish, marine angelfish lay their tiny eggs straight into the water. The angelfish eggs float in the sea, becoming mixed in with the plankton, until they hatch. Unfortunately a vast number of marine angelfish eggs are inadvertently eaten by those many animals that feed on the plankton in the water.

Marine angelfish are most well known for the bright colours and patterns on their bodies. Marine angelfish vary in colour and size depending on the species of marine angelfish, although it is known that the patterns and colours of marine angelfish change drastically as they get older. It is believed that these colour changes indicate the position of the marine angelfish, within the marine angelfish social hierarchy.

Marine angelfish graze on algae on coral reefs and rocks are well as eating smaller fish and crustaceans such as shrimp and small species of prawn. Adult marine angelfish are preyed upon by sharks, marine mammals and humans, but the young and smaller marine angelfish are eaten by many different species of animal both in the water and those based on land (such as birds).

Tiger Shark

The tiger shark is the fourth biggest shark in the world and is found in warmer and tropical waters in the Southern Hemisphere. The tiger shark tends to be found in more coastal waters but tigers sharks are also known to go into the deeper ocean if they need to hunt for food.

The tiger shark is a fierce predator and tiger sharks hunt everything in the water including fish, seals, birds, turtles and even other sharks. The tiger shark gets it's name from the black stripes it has when it is young. Most tiger sharks lose these stripes as they get older.

Like most other species of shark, tiger sharks have sensors on the sides of their heads which enable them to detect small muscle movements from nearby creatures. The tiger shark also has a wedge-shaped head which allows the shark to turn quickly when it needs to. Tiger sharks can reach a top speed of around 20mph which is pretty fast in the water!

Tiger sharks are extremely aggressive animals are thought to be one of the most dangerous sharks for humans to come into contact with. Tiger sharks are solitary hunters and usually do most of their hunting at night when the tiger shark can move through the water unseen.

Female tiger sharks mate every three years or so and the time of year when this happens depends on where the tiger shark lives. Tiger sharks in the Northern Hemisphere mate from March to May, where tiger sharks in the Southern Hemisphere mate from November to January. The eggs hatch inside the female tiger shark and can remain inside her for up to 16 months. When they are big enough, the female tiger shark gives birth to between 10 and 80 baby tiger sharks.

Tiger sharks usually range from between 3 to 5 metres in length. Although much larger specimens have been seen, the largest a tiger shark tends to get is around 5.5 metres long. 

Spiny Dogfish

The spiny dogfish is one of the most abundant species of shark in the world is also commonly known as the piked dogfish, the codshark and the thorndog. The spiny dogfish is the most well-known of the dogfish species and is also thought to be the most well-researched shark species in the world.

The spiny dogfish is found worldwide across the Atlantic, Indian and Pacific Oceans. The spiny dogfish tends to be be found in the warmer coastal waters although it is not uncommon to spot spiny dogfish hunting in the freezing sub-Antarctic waters.

The spiny dogfish is a small-sized shark with a grey coloured body that has a light underside and little white spots on the back of the spiny dogfish. The spiny dogfish also has large eyes and a short snout and unlike many other species of shark, the spiny dogfish does has have an anal fin.

The most distinctive feature of the spiny dogfish are the two spikes found on the back of the spiny dogfish, one spike in front of each dorsal fin. The spikes on the back of the spiny dogfish are mildly poisonous and are mainly used in defence.

The spiny dogfish is a carnivorous animal and therefore survives on a purely meat-based diet. Fish, squid and crustaceans are the most common meals for the spiny dogfish, but the spiny dogfish is also known to hunt octopus and even other sharks.

Due to its relatively large size, aggressive nature and poisonous spikes, the only real predators of the spiny dogfish are larger sharks, humans and the occasional killer whale.

As with some other species of shark, the spiny dogfish does not lays its eggs in the water to hatch, but the spiny dogfish fry instead hatch inside their mother and then emerge into the open ocean. After a gestation period that can last up to 2 years (the longest of any other vertebrate), the female spiny dogfish will produce a little of between 2 and 15 spiny dogfish pups.

Gar

The gar (also known as the garpike) is an elongated species of fish, generally found in freshwater habitats across North and Central America. Despite their similar appearance, the gar is not to be confused with the marine garfish or needlefish that is a common sight throughout the tropical reefs of south-east Asia.

There are seven different species of gar found on the American continent where they can be found in fresh or brackish water habitats such as lakes and reservoirs, and in the larger slow-moving rivers. The gar is most commonly found in eastern parts of North America, Central America and also on a number of the Caribbean islands.

The gar is a generally quite large species of fish, with some individuals able to reach lengths of 3 meters or more. Although not all gar species are quite so big, they are all generally large fish and therefore dominant predators within their environments.

Gar are generally slow-moving fish and so must rely on the power and strength of their jaws in order to catch their prey. Gar have a long jaw which is filled with sharp, needle-like teeth and can often be seen together in small groups as they try to ambush their prey as one.

The gar is a carnivorous and dominant predator within its environment feeding only on other animals in the water. Gar primarily hunt fish, insects and other invertebrates such as crabs along with eggs and other animals in the water.

Due to its large size and aggressive temperament, the gar has few natural predators within its native environment. Larger animals including crocodiles, alligators, large fish species and humans are the main predators of the gar.

Many gar spawn during the warmer spring months between April and June although they have been known to mate until the autumn weather appears in early October. After mating, the female gar lays an average on 10 sticky eggs on a nearby leaf or branch, where they remain until they hatch. As with many other fish species, the gar parents do not look after their young once they have hatched.

Today, the gar is not considered to be a species that is under threat from extinction although gar populations have been decreasing in specific areas mainly due to over-hunting and pollution in the water.

Pike

The pike is a large species of freshwater fish, natively found in North America and across Eurasia. There are five recognised species of this large predatory fish which are the American pickerels, the Northern Pike, the Muskellunge, the Chain Pickerel and the Amur pike. Pikes are also one of the world's oldest fish, thought to have been found on earth for the past 65 million years.

Pike are most commonly found in large bodies of deep, slow-moving water such as lakes, rivers and occasionally in large streams. Pike inhabit areas where there is plenty of cover from the reeds, where they are able to lurk until dinner swims past. Pike are found in North America, Canada, across Europe and into parts of western Asia.

Pike are generally quite large in size, but it is the female pike that often become the largest predators within their environment. Pikes can range in size from just half a meter, to 1.8m in length depending on the species and the area which it inhabits. The grey-green scales of the pike give it perfect camouflage when it is hiding amongst the reeds.

The pike is one of the most easily recognised fish in the world, mainly due to their elongated body shape and sharply pointed head. The teeth of the pike are one of it's most characteristic features as they are pointed and very sharp, to make catching prey more efficient.

Although young pike may have the odd nibble on plants. pike generally have a purely carnivorous diet. Adult pike primarily feed on smaller fish in the water that the pike is able to ambush from it's hiding place amongst the aquatic weeds. Pike also hunt a number of other animals in the water including amphibians like frogs and toads and invertebrates such as snails and spiders.

Due to their large size and naturally aggressive nature, the pike tends to be the most dominant predator within it's environment and adult pike therefore have very few predators in the wild. Smaller pike however are preyed upon by mainly land-dwelling animals from foxes to large birds of prey.

As a rule of thumb, the heavier the pike, the more likely it is that the fish is a female as male pike rarely attains weights of 10 pounds or more. A large female pike can lay up 200,000 eggs at once although this number is often much lower, but is entirely dependent on the size of the fish. Female pike usually spawn in the spring when the weather begins to warm, meaning that the pike fry (babies) have the longest time possible to develop before the cold winter sets in.

Today, although still common across much of it's native range, pike populations are being affected on both the North American and European continents mainly due to over-fishing and chemical pollutants in the water.

Magellanic Penguin

The Magellanic penguin is a small to medium sized species of penguin found inhabiting the rocky islands off the coast of parts of South America. The Magellanic penguin is most closely related to the African penguin, the Galapagos penguin and the Humboldt penguin which it is similar in appearance to. Despite being classed as a threatened species, the Magellanic penguin is one of the most numerous of all of these types of penguin.

The Magellanic penguin is found breed off the coast of Argentina and southern Chile and on the Falkland islands further south. Like other species of penguin the Magellanic penguin spends the majority of it's time hunting for food in the surrounding ocean, coming onto land to nest in large colonies on the beaches.

The Magellanic penguin is a medium sized penguin that can grow up to 76cm in height. Like other penguin species, the flippers of the Magellanic penguin are not that long but act as the perfect tools for propelling the Magellanic penguin through the water when it is in search of food. Like the other penguins in their group, Magellanic penguins have white and brownish black markings, with a broad dark band running across the top of their white chest.

Like other penguin species, the Magellanic penguin is a highly sociable bird, living in flocks with numerous other Magellanic penguin individuals. As well as gathering together in large colonies on the beaches during the breeding season, the Magellanic penguin flocks also spend their time out at sea hunting together rather than on their own.

The Magellanic penguin is a carnivorous predator and it's diet is solely comprised of marine-dwelling animals. The Magellanic penguin primarily hunts cuttlefish and squid in the surrounding waters along with numerous species of fish (including sardines), and krill. Like other penguin species, the Magellanic penguin can dive quite deep for a few minutes at time in order to catch their prey.

The relatively small size of the Magellanic penguin means that it is preyed upon by a number of hungry marine carnivores. Leopard seals and large fur seals are the primary predators of the Magellanic penguin along with sharks and killer whales. Due to the fact that they nest on quite inhospitable land though, the Magellanic penguin has no natural predators on their breeding beaches.

Magellanic penguins nest together on beaches on the rocky islands in their natural range. The female Magellanic penguin lays two eggs in a nest on the beach which are incubated by both parents for up to 40 days. Once hatched, the chicks are cared for by their parents until they are about a month old and are able to fend for themselves.

Today, although quite numerous in some parts, the Magellanic penguin in considered to be a threatened species primarily due to changes in their natural habitats. Oil spills are thought to be the biggest threat to the Magellanic penguin and their native breeding sites across south-east Pacific.

Lionfish

The lionfish (also known as the turkeyfish, tigerfish, dragonfish, scorpionfish, and butterfly cod) is a poisonous spiky fish found in the warmer waters of the western and central Pacific Ocean. The lionfish is a predatory fish hunting small fish, but it's venom is capable of being fatal to larger creatures.

The lionfish is a popular aquarium fish around the world, although the lionfish is better kept in tanks with lots of space and few other fish. The lionfish can live to around 16 years in the wild and lionfish often live longer if looked after well in captivity.

There are around 8 different recognised species of lionfish that are found in the Pacific Ocean. The lionfish is natively found in coastal waters around rocky crevices and coral reefs where there are lots of smaller fish for the lionfish to eat and also places for the lionfish to hide.

The lionfish catches it's prey by hiding in a crevice in the rock or coral and then ambushing it as it swims past.The lionfish then corners it's prey with it's large fins before swallowing it whole.
Lionfish prey on a wide variety of small fish and crustaceans that inhabit the tropical reefs. The lionfish is prey to few predators due to the large size of the lionfish and the fact that the appearance of the lionfish is intimating to other animals. The spikes that protrude from the body of the lionfish contain venom that lionfish uses to defend itself if it is being pursued. The main predators of the lionfish are large fish, eels and humans that catch the lionfish to put into a tank.

Although the lionfish is a solitary animal and they only really come together to mate, a few lionfish inhabit a certain area of the reef. The lionfish group usually contains one male lionfish and a few female lionfish that he mates with. The male lionfish is highly territorial and protects the area in which by himself and his females live.

The female lionfish releases between 2,000 and 15,000 eggs into the water which are fertilised by the male lionfish. The lionfish pair then quickly hide so that their eggs can float into the ocean before being spotted by predators that eat the eggs. The lionfish eggs hatch in just 2 days and the tiny lionfish fry remain near the surface of the water until they are bigger. When the lionfish fry reach nearly an inch in length, they swim down into the ocean to join the reef community.

The Lionfish is also an invasive species, originally from the Indian and Western Pacific oceans. It was brought into Florida as an aquarium fish, and after a hurricane broke some of the aquariums containing the fish, they started to appear around the lower coast of Florida. They have now spread all the way up to Long Island, New York.

When scientists do dives to study the lionfish, sometimes they kill one, and trace it's DNA. The odd thing lately, is that all the fish trace back to an original six or seven Lionfish from the ocean in which they came.

Water Dragon

The water dragon is a large species of lizard native to the forests and jungles of Asia and Australia. Water dragons are arboreal animals meaning that they spend most of their time in the trees, often close to a large body of water.

There are two different species of water dragon, which are the Australian water dragon and the Asian water dragon. The Australian water dragon is the smaller of the two water dragon species and is found on the east coast of Australia. Australian water dragons have powerful legs and sharp claws which help them to climb trees more effectively.

The Asian water dragon is the larger and more colourful of the two water dragon species and is found in forests and jungles throughout India, China, Laos, Vietnam, Burma and Thailand. The Asian water dragon also has a third eye (known as the pineal gland), which is thought to be able to detect difference in light.

Although water dragons are generally tree-dwelling animals, they also spend a great deal of time in or very close to the water. Water dragons are strong and capable swimmers and often leap into the water from the branches high above in order to escape approaching danger.

Like many other lizard species, water dragons are omnivorous animals eating a variety of plant and animal species. Water dragons primarily prey upon small animals such as lizards, frogs and rodents, insects and fish which they catch will there long tongue.

Due to their relatively large size, water dragons have limited predators within their natural environment, although this is entirely dependent on where the area which the water dragon inhabits. Snakes, large birds and carnivorous mammals are the primary predators of the water dragon.

Water dragons hibernate during the cooler winters and begin breeding when they emerge in the spring. The female water dragon digs a burrow in the ground where she lays up to 18 eggs, and then buries them. The water dragon young hatch within a few months and remain close to the nest until they become bigger and more adventurous.

Bottle Nosed Dolphin

Bottlenose Dolphins  are the most common and well-known type of dolphin. Bottlenose dolphins are found inhabiting warm seas worldwide.

Bottlenose dolphins are grey in colour and grow between 2 and 4 meters long. These dolphins typically stay in groups from 15 to 2,000 in number, meaning that bottlenose dolphins can often be found in large groups.

Dolphins are thought to be one of the more intelligent animals of the mammal world, along with bigger primates and humans. Dolphins are thought to communicate to other dolphins through a series of clicking sounds.

Bottlenose dolphins generally have a good relationship with humans and due to their intelligence, bottlenose dolphins have been trained by military forces for tasks such as locating sea mines or detecting and marking enemy divers. In some areas the bottlenose dolphins have been known to help the local fishermen by driving fish towards the fishermen and then eating the fish that escape the fishermens nets. Some interactions with humans however are harmful to the dolphins as people hunt bottlenose dolphins for food, and dolphins are often killed by accident when there is mass tuna fishing.

Bottlenose dolphins are generally known to have a calm and playful temperament, particularly

Discus

• Discus Classification and Evolution

The Discus is a species of tropical Cichlid, found in the Amazon basin of South America. There are three recognised sub-species of the Discus which are the Green Discus, the Blue Discus and the Brown Discus. The Discus was first described by Dr. Heckel in 1840 and despite variations in colour, all are similar in appearance but are found in different geographic locations. There is however some disagreement over the scientific names for each species, but many agree that most captive bred Discus are thought to have originated from these three sub-species.

• Discus Anatomy and Appearance

The Discus is a medium sized Fish, with a round, flattened body and large extended fins which also add to it's disk-like shape (from which it get it's name). Discus have small mouths and small bright red eyes, and vary in colour depending on the species (either green, blue or brown in the wild, but there are many new variations found in aquariums around the world today such as red). The round body of the Discus also has nine dark, vertical stripes which are thought to be used both for camouflage (along with it's colour and flattened body) and to communicate within the school.

• Discus Distribution and Habitat

The Discus is one of only a few Cichlid species found outside of Africa. They are found inhabiting sections of deep, calm, well-wooded waters in the Amazon Basin and it's tributaries. These slow-moving rivers and backwaters of the Amazon river system that stretch through Brazil, Columbia and Peru, provide the perfect habitat for these large Fish, which generally shelter amongst the submerged roots and branches. Discus are known to be fussy about the water conditions in artificial habitats and are not for the inexperienced keeper. In their natural environment, Discus inhabit soft, acidic, and very warm waters, where there is less competition from other Fish.

• Discus Behaviour and Lifestyle

Unlike many other Cichlid species, the Discus is a very sociable Fish and is often found in large groups (known as schools), in their native habitats. Living in these large groups means that the Discus displays very advanced behaviour for a Cichlid, as other species are not schooling Fish. Discus are generally mild mannered but are known to become aggressive within their pair bonds, or when defending their young or territory. One common observation from those kept in tanks, is that the Fish at the bottom of the social ladder, can be bullied extensively by groups of Discus higher up the chain, so much in fact that it can lead to death in some cases.

• Discus Reproduction and Life Cycles

Discus form pair bonds when they are about 75% of their adult size and these pairs tend to remain together for life. They choose a nearly vertical spawning site, which is then cleaned in preparation for the female to lay between 80 and 400 eggs. The male then fertilises them and both parents help to guard their eggs until they hatch. Like other Cichlids, Discus parents care for their young well and even secrete a slimy substance through their scales for their fry to feed off for the first couple of weeks. Discus can live until they are between 10 and 15 years old but it is not uncommon for those kept in well-run artificial habitats, to reach even older ages.

• Discus Diet and Prey

Like many other Fish, Discus will eat almost anything that will fit in their mouths. Despite this, they have a predominately meat-based diet that is high in protein. They mainly feed on small Fish and fry, along with Larvae and other Aquatic Insects, and invertebrates such as Worms. They tend to eat relatively slowly, grazing through the surrounding waters for tasty morsels. Those kept in captivity are also commonly fed Brine Shrimp and Bloodworm which are both protein-rich, along with standard Fish flakes (although this needs to be monitored to avoid over feeding).

• Discus Predators and Threats

Discus inhabit areas where there is plenty of underwater debris for them to hide amongst. Their unique shape, colours and markings also provide them with camouflage from approaching predators in the Amazon river system. Larger species of Fish, Turtles and other water-dwelling animals are the most common predators of the Discus, along with other predators such as Bats and Birds that hunt the Discus from the sky above. Discus populations across South America are also threatened by habitat destruction, caused both by deforestation and pollution of the surrounding water.

• Discus Interesting Facts and Features

The Discus today is an incredibly popular aquarium species and it is thought to be one of the most written about tropical Fish, over a period of just 50 years. Although Fish today are all thought to have come from the green, brown and blue Discus in the wild, others colours are much more common in tanks including yellow, black and red. Today there is a major industry behind the captive breeding of Discus, which primarily occurs in Fish farms in a number of countries in Asia. They are relatively peaceful Fish, co-inhabiting their surroundings with other, generally smaller Fish that provide no competition for food.

• Discus Relationship with Humans

The grace and elegance of the Discus have fascinated Fish enthusiasts from around the world since they were first discovered in South America in the mid 1800s. However, excessive captive breeding has led to the fading of their dark stripes meaning that they can communciate less effectively within the group. They can also be very difficult to keep in artificial habitats as a great deal of care and attention needs to be paid to both their water quality and their feeding, along with the other species that they are sharing their environment with.

• Discus Conservation Status and Life Today

Today, the Discus is listed as a Threatened species in it's natural habitat meaning that if the situation progresses unchanged, the Discus will be at threat from extinction in the wild in the near future. Although many variations of Discus occur in tanks around the world, population numbers of the original Discus species in the wild are declining, primarily due to the decreasing quality of the surrounding water.

Barb

Barb are a small sized group of fish that are naturally found in the freshwater rivers and lakes across the southern hemisphere. There are over 2,000 known species of barb in the world inhabiting the frehswater regions of Asia, Africa and South America.

The barb fish is often referred to as a freshwater shark, due to the fact that barb are one of the few species of freshwater fish to have rows of teeth in their mouths. Despite their small size, barbs are known to be ferocious hunters and are dominant predators in the world of small fish in their natural environment. Barb do only prey upon the fish that are smaller than them, but also on medium sized fish that can sometimes be double the size of the barb.

Due to their small size and bright colours barb are commonly kept in household aquariums worldwide. The most common barb kept in aquariums are the cherry barb (pink/red in colour) and the tiger barb (silver body with thick, black stripes and red fin on it's belly) .

Barb are known to be relatively hardy fish and can easily adapt to changes in the water including changes in pH levels and temperate. It is known that barbs can successfully inhabit unheated tanks, and although this has proved to be successful in many cases, it is not recommended as barb are naturally found in warmer tropical waters.

Due to their aggressive and dominant nature, it is not ideal to keep barbs in artificial tanks with smaller species of tropical fish. At the same time, barb will also hunt medium sized fish if there is a lack of food, and so are best kept on their own (just barbs) or with much larger species of fish.

Barbs are known to lay numerous eggs in order for a few to hatch successfully. The baby barb are called fry and generally hatch within a few days of being laid. Like their hardy barb parents, the barb fry are able to adapt well to changes in their surroundings.

Barbs are opportunists and will therefore eat almost anything that they can find. Although barbs prefer a predominantly meat based diet that includes smaller fish, insects and bloodworm, barb are also known to eat aquatic plants particularly those that are softer and therefore easier to ingest. The exact diet of the barb however, depends on the species and the region in which it inhabits. 

Catfish

Catfish are a group of bottom-feeding fish that are found in freshwater habitats and coastal regions on and around every continent in the world with the exception of Antarctica. Catfish are most easily identified by their flattened broad heads and the long whisker-like barbels that protrude from the mouth of the catfish.

The long barbels of the catfish contain the taste buds of the catfish and so are often most commonly used for smelling and therefore sensing what is about to eat (and to hide from) in the surrounding waters. Despite the name however, not all catfish species have prominent whisker-like barbels.

There are nearly 3,000 known species of catfish in the world but it is thought that the actual number of catfish species could be as high as 4,500 as many species of catfish are found in areas where there is little or no human contact. Although catfish can generally be found in faster-flowing rivers and streams, some catfish species have adapted to living in shallow salt-water environments while other catfish species live their lives in caves underground.

The average catfish is around a meter in length usually slightly less depending on the species. Catfish however can range in size from just a centimetre in length to more than two meters long. The largest species of catfish is the Mekong catfish, which is found inhabiting parts of the Mekong river that flows through Laos, Thailand, Cambodia and Vietnam. The largest Mekong catfish ever found measured nearly 3 meters in length.

Catfish generally have a carnivorous diet, although the tiny catfish species have been known to ingest small aquatic plants. Catfish tend to feed on fish, insects and worms that dwell close to the river bed, along with amphibians such as frogs and newts and occasionally small reptiles and mammals.

Due to the wide diversity and range of the catfish, the catfish has numerous predators all around the world. Large fish, amphibians, reptiles, mammals and even birds all prey on the 3,000 different catfish species.

Female catfish spawn (lay their eggs) close to the surface of the water where they are safe from other bottom-dwelling aquatic animals. Female catfish lay between 10 and 90 little eggs at a time which hatch in less than a week.

Basking Shark

The basking shark is the second largest species of shark (and fish) in the world behind the enormous whale shark. Basking sharks are also commonly known as the sunfish, the elephant shark and the big mouth shark

The basking shark is found inhabiting temperate coastal waters around the world, with the exception of the Indian Ocean. The basking shark is one of only three plankton-feeding shark species and is the largest fish in British waters.

Basking sharks are most well known for their enormous mouths which balloon out in order to take in as much water into it as possible, and are able to process over 1,500 gallons at a time. As filter-feeders, the basking shark's mouth contains hundreds of tiny teeth which are used to filter food particles out of the water.

Basking sharks are generally solitary animals found hunting alone, although basking sharks are also commonly seen in schools of up to 100 basking shark individuals usually during seasonal migrations. Basking sharks are also known to spend most of their time closer to the surface of the water where they can be easily spotted as they munch their way through the ocean.

As with other large fish and shark species, the basking shark is a carnivorous animal meaning that it only gets it's nutrients by eating other animals. Plankton is the primary source of food for the basking shark along with other small organisms such as fish, squid and crustaceans.

As the second largest shark species in the world, the basking shark has few natural predators. Apart from hunting by humans, the great white shark and the killer whale are the only real threat to the basking shark, mainly due to the fact that basking sharks are slow and generally sluggish swimmers.

Basking sharks reach sexual maturity (can begin breeding) when they are about three years old. Basking sharks are known to mate during the warmer summer months, and their pups (the largest of all shark pups) are born live after up to 3 years of development. Basking shark pups are known to become independent immediately, swimming away from their mother just after birth.

Due to over hunting and rising levels of pollution, the world's basking shark populations have severely declined meaning that today, the basking shark is considered to be an animal that is under threat from extinction.

Seahorse

The seahorse is a small species of vertebrate that is found in the tropical shallows and temperate waters around the world. The sea horse is also commonly found around coral reefs where there is plenty of food and places for the seahorse to hide.

The seahorse is most closely related to a pipe fish although, the seahorse does not have scales like most fish and instead the seahorse has a bone structure that is made up of little plates and covered with a thin layer of skin.

There are 32 recognised species of seahorse found in all water types worldwide, with the exception of the polar regions. Seahorses are generally small animals averaging around 10cm in height although this is dependent on the species. Seahorses can also be found in many different colours but the exact colour of the seahorse is down to the particular species of seahorse and the area in which it lives.

Seahorses spend their time bobbing in the sea grasses and coral reefs and due to their colourings, seahorses are able to camouflage themselves pretty effectively into the aquatic plants and larger coral so as to hide from their predators.

The seahorse has a number of distinctive features which help the seahorse to survive in it's marine environment. The seahorse has a long snout for sucking in food and a long tail which the seahorse uses both for moving through the water and also for clinging onto coral and aquatic plants, which the seahorse does by curling this long tail around things in order to anchor itself down.

The seahorse is an omnivorous animal and the seahorse therefore eats a mixture of plant and animal matter which the seahorse does by sucking the food into it's body through it's elongated snout. The seahorse primarily feeds on brine shrimp. plankton, tiny species of fish and algae.

Due to the small size and vulnerability of the seahorse, the seahorse has numerous predators within it's natural environment. Crustaceans such as crabs, fish and rays are all common predators of the seahorse along with humans who harvest the seahorse for use in medicine. The seahorse is also vulnerable to bad weather as in storms, seahorses are often thrown from the place that they were clinging onto and onto the shore.

The sea horse is best known for the remarkable fact that the male seahorse is the one that actually carries the eggs before they hatch. In most other animal species the female of the species if the one to protect the offspring until birth. Instead the female seahorse lays her eggs (anywhere between 8 and 600 eggs are laid depending on the species of seahorse), into the male's brooding pouch where they remain until they hatch within around 3 weeks.

The seahorse is a highly endangered animal mainly due to habitat loss and over-hunting. The seahorse is a popular ingredient in medicine (mainly in the far east), and hundreds to thousands of seahorse are harvested every year for this purpose.

Tang

The tang is a small to medium sized fish that is found in the warmer coastal waters of the tropics. Tangs are well know for their bright colours and are closely related to surgeon fish and unicorn fish.

There are 80 known species of tang, that inhabit the tropical waters of the southern hemisphere, including the largest species of the tang group, the white margin unicorn fish that has been known to grow over a meter long.

Tang are found around shallow coral reefs where there is an abundance of food and plenty of places to hide from approaching predators. The tang is named after the razor-sharp scalpel (also known as tang) at the base of their tails. When the tang feels threatened, it hides in a crevice in the coral or rocks and anchors itself in using this scalpel. The scalpel at the base of the tang's tail can also be used to defend itself if it is caught.

Although the tang is an omnivorous animal, it has a predominantly vegetarian diet. Tang mainly feed on algae and other plants around the coral reefs as well as picking the larger food particles out of the plankton in the water. Later species of tang also feed on small invertebrates and fish. Due to the tang's love of algae, tang can often be seen with sea turtles as they swim along with them cleaning the algae off their shells.

Due to it's small size, the tang has many predators in it's shallow ocean environment including larger fish, eels, sharks, crustaceans and large invertebrates such as jellyfish. Tang are also preyed upon by human who mainly catch them to keep in artificial aquariums.

Tangs are known to breed all year round in the tropical regions, beginning with a male tang securing himself a temporary breeding territory that includes a pair or group of female tang. The female tang release an average of 40,000 eggs into the water which are then fertilised by the male tang. The baby tang are known as fry and hatch in less than a week. Tangs however are reported to breed as well when in captivity.

The tang is one of the most popular species of marine fish to be kept in tanks and aquariums around the world. People are charmed by the peaceful and gentle nature of the tang, along with it's bright colours and the fact that tangs can live for a long time (average is between 12 and 15 years), especially compared to other species of marine fish of a similar size.

Tang are not recommended to be kept in small aquariums as tang have the potential to get pretty big. The most common type of tang kept in salt-water aquariums are the yellow tang and the bright blue regal tang but despite the fact that the tang is popular fish to keep they need to be well looked after and have specific water conditions maintained.