Halomonas titanicae
Scientists at Dalhousie University in Halifax, Canada, collected samples of the R.M.S. Titanic's icicle-like rust formations, called rusticles, in 1991.
Although the formations were teaming with life, nobody had identified the specific microbes on the ship, instead grouping them into broad categories such as bacteria or fungi.
So Henrietta Mann and then graduate student Bhavleen Kaur, now of the Ontario Science Centre, decided to isolate and identify one species of bacteria from the mess of microscopic life-forms.
The one they chose turned out to be a new species, which the pair dubbed Halomonas titanicae. The bacteria is part of a family that had never been seen before in waters as deep as those in which the Titanic sits, about 2.4 miles (3.8 kilometers) below the surface, Kaur said.
Humpback Whale
The humpback whale (Megaptera novaeangliae) is a species of baleen whale. One of the larger rorqual species, adults range in length from 12–16 metres (39–52 ft) and weigh approximately 36,000 kilograms (79,000 lb). The humpback has a distinctive body shape, with unusually long pectoral fins and a knobbly head. It is an acrobatic animal, often breaching and slapping the water. Males produce a complex whale song, which lasts for 10 to 20 minutes and is repeated for hours at a time. The purpose of the song is not yet clear, although it appears to have a role in mating.
Found in oceans and seas around the world, humpback whales typically migrate up to 25,000 kilometres (16,000 mi) each year. Humpbacks feed only in summer, in polar waters, and migrate to tropical or sub-tropical waters to breed and give birth in the winter. During the winter, humpbacks fast and live off their fat reserves. The species' diet consists mostly of krill and small fish. Humpbacks have a diverse repertoire of feeding methods, including the bubble net feeding technique.
Like other large whales, the humpback was and is a target for the whaling industry. Due to over-hunting, its population fell by an estimated 90% before a whaling moratorium was introduced in 1966. Stocks have since partially recovered; however, entanglement in fishing gear, collisions with ships, and noise pollution also remain concerns. There are at least 80,000 humpback whales worldwide. Once hunted to the brink of extinction, humpbacks are now sought by whale-watchers, particularly off parts of Australia, New Zealand, South America, Canada, and the United States.
Humpback whales are rorquals (family Balaenopteridae), a family that includes the blue whale, the fin whale, the Bryde's whale, the sei whale and the minke whale. The rorquals are believed to have diverged from the other families of the suborder Mysticeti as long ago as the middle Miocene. However, it is not known when the members of these families diverged from each other.
Though clearly related to the giant whales of the genus Balaenoptera, the humpback has been the sole member of its genus since Gray's work in 1846. More recently though, DNA sequencing analysis has indicated the Humpback is more closely related to the gray whale (Eschrichtius robustus) and to certain rorquals, such as the fin whale (Balaenoptera physalus) than it is to other rorquals such as the minke whales. If further research confirms these relationships, it will be necessary to reclassify the rorquals.
Arctic Circle
The Arctic Circle is one of the five major circles of latitude that mark maps of the Earth. For Epoch 2011, it is the parallel of latitude that runs 66° 33′ 44″ (or 66.5622°) north of the Equator.
The region north of this circle is known as the Arctic, and the zone just to the south is called the Northern Temperate Zone. The equivalent polar circle in the Southern Hemisphere is called the Antarctic Circle.
The Arctic Circle marks the southern extremity of the polar day (24-hour sunlit day, often referred to as the "midnight sun") and polar night (24-hour sunless night). North of the Arctic Circle, the sun is above the horizon for 24 continuous hours at least once per year and below the horizon for 24 continuous hours at least once per year. On the Arctic Circle those events occur, in principle, exactly once per year, at the June and December solstices, respectively.
In fact, because of atmospheric refraction and because the sun appears as a disk and not a point, part of the midnight sun may be seen on the night of the northern summer solstice up to about 50′ (90 km (56 mi)) south of the Arctic Circle; similarly, on the day of the northern winter solstice, part of the sun may be seen up to about 50′ north of the Arctic Circle. That is true at sea level; those limits increase with elevation above sea level although in mountainous regions, there is often no direct view of the horizon.
The position of the Arctic Circle is not fixed, but directly depends on the Earth's axial tilt, which fluctuates within a margin of 2° over a 40,000 year period, notably due to tidal forces resulting from the orbit of the Moon. The Arctic Circle is currently drifting northwards at a speed of about 15 m (49 ft) per year.
Relatively few people live north of the Arctic Circle due to the Arctic climate. The three largest communities above the Arctic Circle are situated in Russia: Murmansk (population 325,100), Norilsk (135,000), and Vorkuta (85,000). Tromsø (in Norway) has about 62,000 inhabitants. In contrast, the largest North American community north of the circle, Barrow, Alaska, has approximately 4,000 inhabitants. Rovaniemi (in Finland), which lies slightly south of the line, has a population of approximately 58,000, and is the largest settlement in the immediate vicinity of the Arctic Circle.
Tidal Bore
A tidal bore (or simply bore in context, or also aegir, eagre, or eygre) is a tidal phenomenon in which the leading edge of the incoming tide forms a wave (or waves) of water that travel up a river or narrow bay against the direction of the river or bay's current. As such, it is a true tidal wave and not to be confused with a tsunami, which is a large ocean wave traveling primarily on the open ocean.
Bores occur in relatively few locations worldwide, usually in areas with a large tidal range (typically more than 6 metres (20 ft) between high and low water), and where incoming tides are funneled into a shallow, narrowing river or lake via a broad bay. The funnel-like shape not only increases the tidal range, but it can also decrease the duration of the flood tide, down to a point where the flood appears as a sudden increase in the water level. Note the tidal bore takes place during the flood tide and never during the ebb tide.
A tidal bore may take on various forms, ranging from a single breaking wavefront with a roller — somewhat like a hydraulic jump — to ‘undular bores’, comprising a smooth wavefront followed by a train of secondary waves (whelps). Large bores can be particularly very unsafe for shipping,but also present opportunities for river surfing.
Two key features of a tidal bore are the intense turbulence and turbulent mixing generated during the bore propagation, as well as its rumbling noise. The visual observations of tidal bores highlight the turbulent nature of the surging waters. The tidal bore induces a strong turbulent mixing in the estuarine zone, and the effects may be felt along considerable distances. The velocity observations indicate a rapid deceleration of the flow associated with the passage of the bore as well as large velocity fluctuations. A tidal bore creates a powerful roar that combines the sounds caused by the turbulence in the bore front and whelps, entrained air bubbles in the bore roller, sediment erosion beneath the bore front and of the banks, scouring of shoals and bars, and impacts on obstacles. The bore rumble is heard far away because its low frequencies can travel over long distances. The low-frequency sound is a characteristic feature of the advancing roller in which the air bubbles entrapped in the large-scale eddies are acoustically active and play the dominant role in the rumble sound generation.
The word bore derives through Old English from the Old Norse word bára, meaning a wave or swel
Tiger Shark
The tiger shark, Galeocerdo cuvier, is a species of requiem shark and the only member of the genus Galeocerdo. Tiger sharks are relatively large macropredators, capable of attaining a length of over 5 m (16 ft). This shark typically reaches maturity at lengths of 2 to 3 m (6.6 to 9.8 ft). It is found in many tropical and temperate oceans, and is especially common around central Pacific islands. Its name derives from the dark stripes down its body, which resemble a tiger's pattern and fade as the shark matures.
The tiger shark is a solitary, mostly night-time hunter. Its diet involves a wide range of prey, including crustaceans, fish, seals, birds, smaller sharks, squid, turtles, sea snakes, and dolphins.
While the tiger shark is considered to be one of the sharks most dangerous to humans, the attack rate is surprisingly low according to researchers. The tiger is second on the list of number of recorded attacks on humans, with the great white shark being first. They often visit shallow reefs, harbours and canals, creating the potential for encounter with humans.
Tiger sharks are considered a near threatened species due to excessive finning and fishing by humans.
The tiger shark is often found close to the coast, in mainly tropical and sub-tropical waters worldwide, though they can reside in temperate waters. Along with the Great White shark, Pacific sleeper shark, Greenland shark and sixgill shark, tiger sharks are among the largest extant sharks. The shark's behavior is primarily nomadic, but is guided by warmer currents, and it stays closer to the equator throughout the colder months. The shark tends to stay in deep waters that line reefs but does move into channels to pursue prey in shallower waters. In the western Pacific Ocean, the shark has been found as far north as Japan and as far south as New Zealand.
Sperm Whale
The sperm whale, Physeter macrocephalus, is a marine mammal species, order Cetacea, a toothed whale (odontocete) having the largest brain of any animal. The name comes from the milky-white waxy substance, spermaceti, found in the animal's head. The sperm whale is the only living member of genus Physeter. The synonym Physeter catodon refers to the same species. It is one of three extant species in the sperm whale superfamily, along with the pygmy sperm whale and dwarf sperm whale.
A bull can grow to 20.5 metres (67 ft) long. It is the largest living toothed animal. The head can take up to one-third of the animal's length. It has a cosmopolitan distribution across the oceans. The species feeds on squid and fish, diving as deep as 3 kilometres (9,800 ft), which makes it the deepest diving mammal. Its diet includes giant squid and colossal squid. The sperm whale's clicking vocalization is the loudest sound produced by any animal, but its functions are uncertain. These whales live in groups called pods. Pods of females and their young live separately from older males. The females cooperate to protect and nurse their young. Females give birth every three to six years, and care for the calves for more than a decade.
Historically, the sperm whale was also known as the common cachalot; "cachalot" is derived from an archaic French word for "tooth". Over most of the period from the early 18th century until the late 20th century, the sperm whale was hunted to obtain spermaceti and other products, such as sperm oil and ambergris. Spermaceti found many important uses, such as candles, soap, cosmetics and machine oil. Due to its size, the sperm whale could sometimes defend itself effectively against whalers. In the most famous example, a sperm whale attacked and sank the American whaleship Essex in 1820. As a result of whaling, the sperm whale is currently listed as vulnerable by the IUCN. The sperm whale has few natural predators, since few are strong enough to successfully attack a healthy adult; orcas attack pods and kill calves. The sperm whale can live for more than 70 years.
The name sperm whale is an apocopation of spermaceti whale. Spermaceti is the semi-liquid, waxy substance found in the spermaceti organ or case in front of and above the skull bone and also in the junk, the area below the spermaceti organ and just above the upper jaw. The case consists of a soft white, waxy substance saturated with spermaceti oil. The junk is composed of cavities filled with the same wax and spermaceti oil and intervening connective tissue. The sperm whale is also known as the "cachalot", which is thought to derive from the archaic French for "tooth" or "big teeth", as preserved for example in cachau in the Gascon dialect (a word of either Romance or Basque origin). The etymological dictionary of Corominas says the origin is uncertain, but it suggests that it comes from the vulgar Latin cappula, plural of cappulum, sword hilt. According to Encarta Dictionary, the word cachalot came to English "via French from Spanish or Portuguese cachalote, perhaps from [Portuguese] cachola, 'big head'".
Ghost Knifefish
The ghost knifefishes are a family, Apteronotidae, of ray-finned fishes in the order Gymnotiformes. These fish can be found in the freshwater of Panama and South America.
They are distinguished from other gymnotiform fishes by the presence of a caudal fin (all other families lack a caudal fin) as well as a fleshy dorsal organ represented by a longitudinal strip along the dorsal midline. The longest Apteronotid is Apteronotus magdalenensis, reaching 1.3 metres. These nocturnal fish have small eyes. Also, sexual dimorphism exists in some genera in snout shape and jaws.
Apteronotids use a high frequency tone-type (also called wave-type) electric organ discharge (EOD) to communicate.
Many Apteronotids are aggressive predators of small aquatic insect larvae and fishes, though there are also piscivorous and planktivorous species. Magosternarchus spp. are very unusual, preying on the tails of other electric fishes. Other species, such as Sternarchorhynchus and Sternarchorhamphus, have tubular snouts and forage on the beds of aquatic insect larvae and other small animals which burrow into the river bottom. At least one species (Sternarchogiton nattereri) eats freshwater sponges which grow on submerged trees, stumps, and other woody debris. The genus Apteronotus is artificial and many of the species do not actually belong in it.
The black ghost knifefish (Apteronotus albifrons) and brown ghost knifefish (Apteronotus leptorhynchus) are readily available as aquarium fish. Others, are known to appear in the trade, but are quite rare.
Tiger Catfish
Pseudoplatystoma is a genus of several South American catfish species of family Pimelodidae. The three species are known by a number of different common names. They inhabit the major rivers of north-eastern Argentina, Paraguay, Peru, Bolivia, Uruguay and Brazil. They prefer the main channels and tend to stay at maximum depth. They have robust bodies, and are important food fish.
In their native waters, these fish may be called Surubí in guaraní. This name is also used in some Spanish speaker countries. In Peruvian Spanish is called Doncella or Zúngaro. P. corruscans may be called molequepintado. They often are referred to in the vernacular as or
Bagre rayado or Pintadillo (tiger catfish or tiger–shovelnose). P. corruscans, P. fasciatum, and P. tigrinum are also known as Spotted Sorubim, Barred Sorubim, and Tiger Sorubim, respectively. This genus contains the fish commonly known as the tiger shovelnose catfish in the aquarium hobby, though the species in this genus are relatively easy to confuse.
Pseudoplatystoma species live in a diverse range of habitats such as great rivers, lakes, side channels, floating meadows, and flooded forests. P. fasciatum is found in river beds and sometimes in flooded forests. Though it is biologically similar to P. tigrinum, this fish seems to favor shadier streams. P. tigrinum occurs in estuarine zones, mainly upstream of the first rapids up to the basin's headwaters. They live in the main bed of slow or fast zones, and the juveniles particularly live in flooded forests.
Pseudoplatystoma species are all large, boldly striped or spotted catfishes. They are familiar due to their distinctively marked color patterns. They are also recognized due to a depressed head, an occipital process extending backward to contact the pre dorsal plate, and a very long fontanel.
Goodwin Sands
The Goodwin Sands are a 10-mile-long sand bank in the English Channel, lying six miles east of Deal in Kent, England. The Brake Bank lying shorewards is part of the same geological unit. As the shoals lie close to major shipping channels, more than 2,000 ships are believed to have been wrecked upon them, and as a result they are marked by lightvessels and buoys. Notable shipwrecks include the VOC ship Rooswijk, HMS Stirling Castle, the SS Montrose and the South Goodwin Lightship'. Several naval battles have been fought nearby, including the Battle of Goodwin Sands in 1652 and the Battle of Dover Strait in 1917.
There is currently a lightship on the end of the sands, on the farthest part out, to warn ships. The sands were once covered by two lighthouses on the Kent mainland, one each at the north and south ends of the sands. The southern lighthouse is now owned by the National Trust, and the northern one is still in operation.
Bluntnose Sixgill Shark
The bluntnose sixgill shark, Hexanchus griseus, often simply called the cow shark, is the largest hexanchoidshark, growing to more than 5.4 m (18 ft) in length.
The bluntnose sixgill shark is a member of the Hexanchidae family. Many of its relatives are extinct. The living species that are closest genetically include the dogfish, the Greenland shark, as well as other six- and sevengilled sharks. There are more closely related relatives in the fossil record than living species. Some of the shark's relatives date back to 200 million years ago. This shark is a notable species due to both its primitive and current physical characteristics.
This species typically inhabits depths greater than 90 m (300 ft), and has been recorded as deep as 1,875 m (6,150 ft). Like many deep-sea creatures, the bluntnose sixgill shark is known to undertake nightly vertical migrations (travelling surfaceward at night, returning to the depths before dawn).
The bluntnose sixgill shark can be seen at depths of 30 m (100 ft) and shallower during parts of the year in some specific places e.g. Flora Islet, near Hornby Island, Sightings during shallow evening dives in Whytecliff Park West Vancouver in British Columbia, in Puget Sound, Monterey Canyon off Monterey, California and in fjords in Norway. The sharks are deepsea sharks, but like most fish that prefer the deep, they come to the shallower depths to feed.
Clownfish
Clownfish or anemonefish are fishes from the subfamily Amphiprioninae in the family Pomacentridae. About twenty-nine species are recognized, one in the genus Premnas, while the remaining are in the genus Amphiprion. In the wild they all form symbiotic mutualisms with sea anemones. Depending on species, clownfish are overall yellow, orange, reddish or blackish, and many show white bars or patches. The largest can reach a length of 18 centimetres (7.1 in), while some barely can reach 10 centimetres (3.9 in). In popular culture, "Finding Nemo" by Pixar / Disney prominently features clownfish as the main characters.
Clownfish are native to warmer waters of the Indian and Pacific oceans, including the Great Barrier Reef and the Red Sea. While most species have restricted distributions, others are widespread. They are generally highly host specific, and especially the genera Heteractis and Stichodactyla, and the species Entacmaea quadricolor are frequent partners.
Clownfish live at the bottom of the sea in sheltered reefs or in shallow lagoons, usually in pairs. They are also found in northwest Australia, southeast Asia, Japan and the Indo-Malaysian region. There are no clownfish in the Caribbean.
Clownfish live in pairs inhabiting a single anemone. When the female dies, the dominant male changes sex and becomes the female. This life history strategy is known as sequential hermaphroditism. Because clownfish are all born as males, they are protandrous hermaphrodites (pro=first; androus=male). On the top of the hierarchy is the reproducing female followed by the mating male. Below them are a bunch of non-mating males. But, if the female dies, the whole hierarchy gets disrupted. The predominant male then morphs into a female and chooses a partner from the various non-mating males. The largest fish in the group is a female and the second biggest is a male. All the other clownfish are neuter, which means they have not fully developed functioning sex organs for either gender. If the female should die, the male will change sex, while the biggest neuter clownfish will develop functioning male sex organs to replace the male.
In a group of clownfish, there is a strict hierarchy of dominance. The largest and most aggressive female is found at the top. Only two clownfish, a male and a female, in a group reproduce through external fertilization. The clownfish are hermaphrodites, meaning that they develop into males first, and when they mature, they become females. Also, as mentioned earlier, more than one clownfish is able to live in a sea anemone. If the female clownfish is removed from the group, such as by death, one of the largest and most dominant males would become a female. The rest of the remaining males will move up a rank on the hierarchy.
Fiddler Crab
A fiddler crab, sometimes known as a calling crab, may be any of approximately 94 species of semi-terrestrial marine crabs which make up the genus Uca. As members of the family Ocypodidae, fiddler crabs are most closely related to the ghost crabs of the genus Ocypode. This entire group is composed of small crabs – the largest being slightly over two inches across. Fiddler crabs are found along sea beaches and brackish inter-tidal mud flats, lagoons and swamps.
Like all crabs, fiddler crabs shed their shells as they grow. If they have lost legs or claws during their present growth cycle a new one will be present when they molt. If the large fiddle claw is lost, males will develop one on the opposite side after their next molt. Newly molted crabs are very vulnerable because of their soft shells. They are reclusive and hide until the new shell hardens.
Fiddler crabs communicate by a sequence of waves and gestures; males have an oversized claw or cheliped; used in clashes of ritualised combat of courtship over a female and signal their intentions between conspecifics. The movement of the smaller claw from ground to mouth during feeding underlines the crabs' common name; it seems that animal plays the larger claw somewhat like a fiddle.
Fiddler crabs live rather brief lives of no more than two years (up to three years in captivity). During courtship, the males wave their oversized claws high in the air and tap them on the ground in an effort to attract females. Fights between males will also occur, which are presumably meant to impress the females; if a male loses his larger claw, the smaller one will begin to grow larger and the lost claw will regenerate into a new (small) claw. For at least some species of fiddler crabs, however, the small claw remains small, while the larger claw regenerates over a period of several molts, being about half its former size after the first molt. The female fiddler carries her eggs in a mass on the underside of her body. She remains in her burrow during a two week gestation period, after which she ventures out to release her eggs into the receding tide. The larvae remain planktonic for a further two weeks.
Nurse Shark
The nurse shark, Ginglymostoma cirratum, is a shark in the nurse sharks (Ginglymostomatidae) family, the only member of its genus Ginglymostoma. Nurse sharks can reach a length of 4.3 m (14 ft) and a weight of 330 lbs (150 kg).
The nurse shark is a common inshore bottom-dwelling shark, found in tropical and subtropical waters on the continental and insular shelves. It is frequently found at depths of one metre or less but may occur down to 75 m. Its common habitats are reefs, channels between mangrove islands and sand flats. It occurs in the Western Atlantic from Rhode Island down to southern Brazil; in the Eastern Atlantic from Cameroon to Gabon (and possibly ranges further north and south); in the Eastern Pacific from the southern Baja California to Peru; and around the islands of the Caribbean.
Nurse sharks are nocturnal animals, spending the day in large inactive groups of up to 40 individuals. Hidden under submerged ledges or in crevices within the reef, the nurse sharks seem to prefer specific resting sites and will return to them each day after the night's hunting. By night, the sharks are largely solitary; they spend most of their time rifling through the bottom sediments in search of food. Their diet consists primarily of crustaceans, molluscs, tunicates, sea snakes, and other fish, particularly stingrays.
Elephant Seal
Elephant seals are large, oceangoing seals in the genus Mirounga. There are two species: the Northern Elephant Seal (M. angustirostris) and the Southern Elephant Seal (M. leonina). Both were hunted to the brink of extinction by the end of the nineteenth century, but numbers have since recovered. The Northern Elephant Seal, somewhat smaller than its southern relative, ranges over the Pacific coast of the U.S., Canada and Mexico. The most northerly breeding location on the Pacific Coast is at Race Rocks, at the southern tip of Vancouver Island in the Strait of Juan de Fuca. The Southern Elephant Seal is found in the southern hemisphere on islands such as South Georgia, Macquarie Island, and on the coasts of New Zealand, South Africa, and Argentina in the Peninsula Valdés, which is the fourth largest elephant seal colony in the world.
Elephant seals take their name from the large proboscis of the adult males (bulls) which resembles an elephant's trunk. The bull's proboscis is used in producing extraordinarily loud roaring noises, especially during the mating season. More importantly, however, the nose acts as a sort of rebreather, filled with cavities designed to reabsorb moisture from the animals' exhalations. This is important during the mating season when the male seals rarely leave the beach to feed and therefore must conserve body moisture as they have no incoming source of water. Bulls of both the Northern Elephant Seal and the Southern Elephant Seal reach a length of 16 ft (5 m) and a weight of 6,000 lb (2,700 kg) and are much larger than the cows, which typically measure about 10 ft (3 m) and 1,900 lb (900 kg). The largest known bull elephant seal weighed 11,000 lb (5,000 kg) and measured 22.5 ft (6.9 m) in length. This makes the elephant seal the largest member of the order Carnivora.
Leopard Shark
The leopard shark (Triakis semifasciata) is a species of houndshark, family Triakidae, found along the Pacific coast of North America from the U.S. state of Oregon to Mazatlán in Mexico. Typically measuring 1.2–1.5 m (3.9–4.9 ft) long, this slender-bodied shark is immediately identifiable by the striking pattern of black saddle-like markings and large spots over its back, from which it derives its common name. Large schools of leopard sharks are a common sight in bays and estuaries, swimming over sandy or muddy flats or rock-strewn areas near kelp beds and reefs. They are most common near the coast, in water less than 4 m (13 ft) deep.
Active-swimming predators, groups of leopard sharks often follow the tide onto intertidal mudflats to forage for food, mainly clams, spoon worms, crabs, shrimp, bony fish, and fish eggs. Most leopard sharks tend to remain within a particular area rather than undertaking long movements elsewhere, which has led to genetic divergence between populations of sharks living in different regions. This species is aplacental viviparous, meaning that the young hatch inside the uterus and are nourished by yolk. From March to June, the female gives birth to as many as 37 young after a gestation period of 10–12 months. It is relatively slow-growing and takes many years to mature.
Harmless to humans, the leopard shark is caught by commercial and recreational fisheries for food and the aquarium trade. This species is mostly fished in the waters off California where, after a period of population decline in the 1980s, new fishing regulations in the early 1990s reduced harvesting to sustainable levels. The International Union for Conservation of Nature has assessed this species as of Least Concern, while noting that local stocks may easily become overfished because of the shark's slow growth and limited migratory habits.
The leopard shark occurs in the cool to warm-temperate continental waters of the northeastern Pacific Ocean, from Coos Bay, Oregon to Mazatlán, Mexico, including the Gulf of California. It favors muddy or sandy flats within enclosed bays and estuaries, and may also be encountered near kelp beds and rocky reefs, or along the open coast. Numbers have been known to gather near discharges of warm effluent from power plants. Leopard sharks generally swim close to the bottom and are most abundant from the intertidal zone to a depth of 4 m (13 ft), though they may be found as deep as 91 m (299 ft). Many leopard sharks, particularly in the north, leave their coastal habitats in winter and return in early spring. A study in Tomales Bay in northern California determined that they depart when the water temperature drops below 10–12° C (50–54° F); one tagged shark was found to have swum some 140 km (87 mi) south.
Barramundi
The Barramundi (Lates calcarifer), also known as Asian Seabass, is a species of catadromous fish in familyLatidae of order Perciformes. The native species is widely distributed in the Indo-West Pacific region from the Persian Gulf, through Southeast Asia to Papua New Guinea and Northern Australia. Known in Thai language as Pla Krapong (Thai: ปลากระพง), it is very popular in Thai cuisine. It is known as pandugappa in the Telugu language in India.
Barramundi is a loanword from an Australian Aboriginal language of the Rockhampton area in Queensland Originally, the name barramundi referred to saratoga and Gulf saratoga. meaning "large-scaled river fish". However, the name was appropriated for marketing reasons during the 1980s, a decision which has aided in raising the profile of this fish significantly.L. calcarifer is broadly referred to as Asian seabass by the international scientific community, but is also known as giant perch, giant seaperch, Australian seabass, and by a variety of names in other local languages, such as Ikan Siakap or Ikan Kakap Putih in Indonesian and also known as selunsung in local sabahan. 'Barra Mundi' when pronounced as two words, is clearly of Indian origin meaning 'big head'.
Reef Squid
The Caribbean Reef Squid (Sepioteuthis sepioidea), also known as just the Reef Squid, is a small (20 cm) torpedo-shaped squid with fins that extend nearly the entire length of the body and undulate rapidly as it swims. The squid has recently become notable when it was discovered that it could fly out of the water; a discovery which finally led to identification of six species of flying squid.
The Caribbean Reef Squid is found throughout the Caribbean Sea as well as off the coast of Florida, commonly in small schools of 4-30 in the shallows associated with reefs. The habitat of the Reef Squid changes according to the squid's stage of life and size. New hatchlings tend to reside close to the shore in areas from 0.2-1 meters below the surface on or under vegetation. Young small squid typically congregate in shallow turtle grass near islands and remain several centimeters to two meters from the surface to avoid bird predators. Adults venture out into open water and can be found in depths up to 100 m. When mating, adults are found near coral reefs in depths of 1.5-8 m. The Caribbean Reef Squid is the only squid species commonly sighted by divers over inshore reefs in the Florida, Bahamas and Caribbean region.
Killer Whale
The killer whale (Orcinus orca), commonly referred to as the orca, and less commonly as the blackfish, is a toothed whale belonging to the oceanic dolphin family. Killer whales are found in all oceans, from the frigid Arctic and Antarctic regions to tropical seas. Killer whales as a species have a diverse diet, although individual populations often specialize in particular types of prey. Some feed exclusively on fish, while others hunt marine mammals such as sea lions, seals, walruses and even large whales. Killer whales are regarded as apex predators, lacking natural predators and preying on even large sharks.
Killer whales are highly social; some populations are composed of matrilineal family groups which are the most stable of any animal species. Their sophisticated hunting techniques and vocal behaviors, which are often specific to a particular group and passed across generations, have been described as manifestations of culture.
The IUCN currently assesses the orca's conservation status as data deficient because of the likelihood that one or more killer whale types are separate species. Some local populations are considered threatened or endangered due to prey depletion, habitat loss, pollution (by PCBs), capture for marine mammal parks, and conflicts with fisheries. In late 2005, the killer whales known as the "southern resident killer whales" were placed on the U.S. Endangered Species list.
Wild killer whales are not considered a threat to humans, although there have been cases of captives killing or injuring their handlers at marine theme parks. Killer whales feature strongly in the mythologies of indigenous cultures.
Pleco
Hypostomus plecostomus is the scientific name for a type of freshwater tropical Central and South American fish belonging to the family Loricariidae. They are large algae eaters, and to differentiate them from small algae eaters, they are often referred to as plecostomus, often abbreviated as plecos or plecs. They are extremely popular in aquaria for their ability to clean tanks by eating algae growth. In Malaysia, these fish are called 'ikan bandaraya' or 'municipal fish' in English because of their ability to clean fish tanks. These friendly-natured fish can typically be purchased when about 8 cm (3 inches) and may grow up to 60 cm (2 ft) if there is adequate room, making them mostly impracticable for any but the largest aquariums.
Plecos are omnivorous but, in the wild, feed mostly on plant material at night. During the day, their unusual omega irides block a lot of the light out of their eyes, but they are usually open at night. They can roll their eye within their sockets.
As they age, their foreheads enlarge in a peculiar manner. Plecos may become more peaceful with age and are best kept individually in tanks. Because of their potentially large size and peaceful behaviour, it may be advisable to procure a less aggressive catfish. In a suitably large tank, a solitary plecostomus will live amicably enough in a community alongside other tropical fish. These catfish may survive in tanks with "cold-water" species like goldfish, but it is generally not advised due to the different temperature preferences and the fact that some plecos will suck the protective slime coat off the goldfish. This however would indicate your pleco is starving and seeking the algae stuck to the slime coat.
Plecostomus catfish are some of the most commonly kept algae-eating catfish, and are also some of the largest. Individuals measuring over 60 cm (2 ft) long have been reported in ponds and large tanks; most people think they only grow large enough for their aquarium, but a small tank may only slow their rate of growth. Their growth may also become stunted in a smaller tank, leading to bad health and possibly an early death.
River Dolphins
River dolphins are four living species of dolphin which reside in freshwater rivers and estuaries. River dolphins inhabit areas of Asia and South America. They are classed in the Platanistoidea superfamily of cetaceans. Three species live in fresh water rivers. The fourth species, the La Plata Dolphin, lives in salt-water estuaries and near-shore marine environments. However, it is scientifically classed in the river dolphin group rather than the oceanic dolphin family.
River dolphins are in danger of extinction due to habitat loss, hunting by humans, and naturally low numbers.
The largest river dolphins usually grow up to 2.4 meters (8 feet) long, but most of the animals are smaller. River dolphins may be white, pink, yellow, brown, gray, or black.
The four families of river dolphins are classified by Rice, 1998 as belonging to Platanistoidea. Formerly Platanistidae was listed as the only extant family of the Platanistoidea superfamily. The previously accepted classification treated all four families as belonging to this family and treated the Ganges and Indus River Dolphins as separate species. Five lineages of dolphin have evolved to live in big, muddy rivers. River dolphins are thought to have relictual distributions. Their ancestors originally occupied marine habitats, but were then displaced from these habitats by modern dolphin lineages. Many of the morphological similarities and adaptations to freshwater habitats arose due to convergent evolution. A December 2006 survey found no members of Lipotidae (commonly known as the Yangtze River dolphin) and declared the species functionally extinct.
