|
Tunas
A tuna is a saltwater fish that belongs to the tribe Thunnini, a subgrouping of the Scombridae (mackerel) family. The Thunnini comprise 15 species across five genera, the sizes of which vary greatly, ranging from the bullet tuna (max length: , weight: ) up to the Atlantic bluefin tuna (max length: , weight: ), which averages and is believed to live up to 50 years. Tuna, opah and mackerel sharks are the only species of fish that can maintain a body temperature higher than that of the surrounding water. An active and agile predator, the tuna has a sleek, streamlined body, and is among the fastest-swimming pelagic fish – the yellowfin tuna, for example, is capable of speeds of up to . Greatly inflated speeds can be found in early scientific reports and are still widely reported in the popular literature. Found in warm seas, the tuna is commercially fished extensively as a food fish, and is popular as a bluewater game fish. As a result of overfishing, some tuna species, su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern Bluefin Tuna
The southern bluefin tuna (''Thunnus maccoyii'') is a tuna of the family (biology), family Scombridae found in open southern Hemisphere waters of all the world's oceans mainly between 30th parallel south, 30°S and 50th parallel south, 50°S, to nearly 60th parallel south, 60°S. At up to and weighing up to , it is among the larger bony fishes. Southern bluefin tuna, like other pelagic tuna species, are part of a group of bony fishes that can maintain their body core temperature up to above the ambient temperature. This advantage enables them to maintain high metabolic output for predation and migrating large distances. The southern bluefin tuna is an opportunistic feeder, preying on a wide variety of fish, crustaceans, cephalopods, salps, and other marine animals. Environmental/physical challenges The southern bluefin tuna is a predatory organism with a high metabolic need. These are pelagic animals, but migrate vertically through the water column, up to in depth. They also m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thunnus
''Thunnus'' is a genus of ocean-dwelling, ray-finned bony fish from the mackerel family, Scombridae. More specifically, ''Thunnus'' is one of five genera which make up the tribe Thunnini – a tribe that is collectively known as the tunas. Also called the true tunas or real tunas, ''Thunnus'' consists of eight species of tuna (more than half of the overall tribe), divided into two subgenera. The word is the Middle Latin form of the Greek (, "tuna, ") – which is in turn derived from (, "to rush; to dart"). The first written use of the word was by Homer. Their coloring, metallic blue on top and shimmering silver-white on the bottom, helps camouflage them from above and below. Atlantic bluefin tuna, the largest member of this genus, can grow to long and weigh up to . All tunas are extremely strong swimmers, and the yellowfin tuna is known to reach speeds of up to when pursuing prey. As with all tunas, members of this genus are warm-blooded, which is a rare trait among fis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albacore
The albacore (''Thunnus alalunga''), known also as the longfin tuna, is a species of tuna of the order Perciformes. It is found in temperate and tropical waters across the globe in the epipelagic and mesopelagic zones. There are six distinct stocks known globally in the Atlantic, Pacific, and Indian oceans, as well as the Mediterranean Sea. The albacore has an elongate, fusiform body with a conical snout, large eyes, and remarkably long pectoral fins. Its body is a deep blue dorsally and shades of silvery white ventrally. Individuals can reach up to in length. Albacore are pelagic predators that eat a wide variety of foods, including but not limited to fish, crustaceans, and cephalopods. They are unique among most tuna in that their primary food source is cephalopods, with fish making up a much smaller portion of their diet. Reproduction usually occurs from November to February and is oviparous. An adult female can release over two million eggs in a single cycle. Fry (juvenile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auxis
''Auxis'' is a genus of ocean-dwelling ray-finned bony fish in the family Scombridae, and tribe Thunnini, also known as the tunas. ''Auxis'', commonly and collectively called the frigate tunas, is one of five genera of tunas which comprise the Thunnini tribe. Species There are four species in the genus ''Auxis'', which were formerly regarded as two polytypic species, each with two subspecies. In 2021, the species ''Auxis koreanus'' was described from South Korea. * '' Auxis brachydorax'' Collette & Aadland, 1996 * '' Auxis eudorax'' Collette & Aadland, 1996 * '' Auxis koreanus'' Nam et al., 2021 * '' Auxis rochei'' Risso, 1810 (bullet tuna) * '' Auxis thazard'' Lacépède, 1800 (frigate tuna) Description ''Auxis'' can reach a length of . They have a strong, fusiform body with a sharpened head. The teeth are small and conical. The two dorsal fins are separated by a wide gap. The pectoral fins are short. They have a dark, blue-black back, the top of the head may be deep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlantic Bluefin Tuna
The Atlantic bluefin tuna (''Thunnus thynnus'') is a species of tuna in the family Scombridae. It is variously known as the northern bluefin tuna (mainly when including Pacific bluefin as a subspecies), giant bluefin tuna or individuals exceeding and formerly as the tunny. Atlantic bluefins are native to both the western and eastern Atlantic Ocean, as well as the Mediterranean Sea. They have become extinct in the Black Sea. The Atlantic bluefin tuna is a close relative of the other two bluefin tuna species—the Pacific bluefin tuna and the southern bluefin tuna. Atlantic bluefin tuna have been recorded at up to in weight, and rival the black marlin, blue marlin, and swordfish as the largest Perciformes. Throughout recorded history, the Atlantic bluefin tuna has been highly prized as a food fish. Besides their commercial value as food, the great size, speed, and power they display as apex predators has attracted the admiration of fishermen, writers, and scientists. The At ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelagic Fish
Pelagic fish live in the pelagic zone of ocean or lake waters—being neither close to the bottom nor near the shore—in contrast with demersal fish that do live on or near the bottom, and reef fish that are associated with coral reefs. The marine pelagic environment is the largest aquatic habitat on Earth, occupying 1,370 million cubic kilometres (330 million cubic miles), and is the habitat for 11% of known fish species. The oceans have a mean depth of . About 98% of the total water volume is below , and 75% is below . Moyle and Cech, p. 585 Marine pelagic fish can be divided into coastal (inshore) fish and oceanic (offshore) fish. Coastal pelagic fish inhabit the relatively shallow and sunlit waters above the continental shelf, while oceanic pelagic fish inhabit the vast and deep waters beyond the continental shelf (even though they also may swim inshore). Pelagic fish range in size from small coastal forage fish, such as herrings and sardines, to large apex pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skipjack Tuna
The skipjack tuna (''Katsuwonus pelamis'') is a medium-sized perciform fish in the tuna family, Scombridae. It is otherwise known as the balaya (Sri Lanka), bakulan/kayu (North Borneo), tongkol/aya (Malay Peninsula/Indonesia), aku (Hawaii), cakalang (Indonesia), katsuo, arctic bonito, mushmouth, oceanic bonito, striped tuna or victor fish. It grows up to 1 m (3 ft) in length. It is a cosmopolitan pelagic fish found in tropical and warm-temperate waters. It is a very important species for fisheries. Description It is a streamlined, fast-swimming pelagic fish, common in tropical waters throughout the world, where it inhabits surface waters in large shoals (up to 50,000 fish), feeding on fish, crustaceans, cephalopods, and mollusks. It is an important prey species for sharks and large pelagic fishes and is often used as live bait when fishing for marlin. It has no scales, except on the lateral line and the corselet (a band of large, thick scales forming a circle around th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yellowfin Tuna
The yellowfin tuna (''Thunnus albacares'') is a species of tuna found in pelagic waters of tropical and subtropical oceans worldwide. Yellowfin is often marketed as ahi, from the Hawaiian language, Hawaiian , a name also used there for the closely related bigeye tuna. The species name, ''albacares'' ("white meat") can also lead to confusion: in English, the albacore (''Thunnus alalunga'') is a different species, while yellowfin is officially designated ''albacore'' in French language, French and referred to as ''albacora'' by Portuguese fishermen. Description The yellowfin tuna is among the larger tuna species, reaching weights over , but is significantly smaller than the Atlantic bluefin tuna, Atlantic and Pacific bluefin tuna, Pacific bluefin tunas, which can reach over , and slightly smaller than the bigeye tuna and the southern bluefin tuna. The second dorsal fin and the anal fin, as well as the finlets between those fins and the tail, are bright yellow, giving this fish its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Katsuwonus
The skipjack tuna (''Katsuwonus pelamis'') is a medium-sized perciform fish in the tuna family, Scombridae. It is otherwise known as the balaya (Sri Lanka), bakulan/kayu (North Borneo), tongkol/aya (Malay Peninsula/Indonesia), aku (Hawaii), cakalang (Indonesia), katsuo, arctic bonito, mushmouth, oceanic bonito, striped tuna or victor fish. It grows up to 1 m (3 ft) in length. It is a cosmopolitan pelagic fish found in tropical and warm-temperate waters. It is a very important species for fisheries. Description It is a streamlined, fast-swimming pelagic fish, common in tropical waters throughout the world, where it inhabits surface waters in large shoals (up to 50,000 fish), feeding on fish, crustaceans, cephalopods, and mollusks. It is an important prey species for sharks and large pelagic fishes and is often used as live bait when fishing for marlin. It has no scales, except on the lateral line and the corselet (a band of large, thick scales forming a circle around th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yellowfin Tuna
The yellowfin tuna (''Thunnus albacares'') is a species of tuna found in pelagic waters of tropical and subtropical oceans worldwide. Yellowfin is often marketed as ahi, from the Hawaiian language, Hawaiian , a name also used there for the closely related bigeye tuna. The species name, ''albacares'' ("white meat") can also lead to confusion: in English, the albacore (''Thunnus alalunga'') is a different species, while yellowfin is officially designated ''albacore'' in French language, French and referred to as ''albacora'' by Portuguese fishermen. Description The yellowfin tuna is among the larger tuna species, reaching weights over , but is significantly smaller than the Atlantic bluefin tuna, Atlantic and Pacific bluefin tuna, Pacific bluefin tunas, which can reach over , and slightly smaller than the bigeye tuna and the southern bluefin tuna. The second dorsal fin and the anal fin, as well as the finlets between those fins and the tail, are bright yellow, giving this fish its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesotherm
A mesotherm (from Greek μέσος ''mesos'' "intermediate" and ''thermē'' "heat") is a type of animal with a thermoregulatory strategy intermediate to cold-blooded ectotherms and warm-blooded endotherms. Definition Mesotherms have two basic characteristics: # Elevation of body temperature via metabolic production of heat. # Weak or absent metabolic control of a particular body temperature. The first trait distinguishes mesotherms from ectotherms, the second from endotherms. For instance, endotherms, when cold, will generally resort to shivering or metabolizing brown fat to maintain a constant body temperature, leading to higher metabolic rates. A mesotherm, however, will experience lower body temperatures and lower metabolic rates as ambient temperature drops. In addition, mesotherm body temperatures tend to rise as body size increases (a phenomenon known as gigantothermy), unlike endotherms. This reflects the lower surface area to volume ratio in large animals, which reduces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of living fish species are ray-finned fish, belonging to the class Actinopterygii, with around 99% of those being teleosts. The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts. Fish would continue to evolve through the Paleozoic era, diversifying into a wide variety of forms. Many fish of the Paleozoic developed external armor that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many (such as sharks) became formidable marine predators rather than just the prey of arthropods. Mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Albacore")
