|
Atlantic Silverside
The Atlantic silverside (''Menidia menidia''), also known as spearing in the northeastern United States, is a small species of fish from the West Atlantic, ranging from the Gulf of St. Lawrence in Canada to northeastern Florida in the USA. It is one of the most common fish in the Chesapeake Bay and in the Barnegat Bay. It is a common subject of scientific research because of its sensitivity to environmental changes. The fish is about long, mostly silver and white. It eats smaller (biotic) animals and plants – small crustaceans, algae, annelid worms, shrimp, zooplankton, copepods, amphipods, squid, and insects. The Atlantic silverside's predators are larger predatory fish – striped bass, blue fish, Atlantic mackerel – and many water birds, including egrets, terns, cormorants, and gulls. The abiotic factors the Atlantic silverside needs to survive varies for populations of fish based on their geographical location. A rule of thumb for the species includes an average ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Linnaeus
Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the modern system of naming organisms. He is known as the "father of modern taxonomy". Many of his writings were in Latin; his name is rendered in Latin as and, after his 1761 ennoblement, as . Linnaeus was born in Råshult, the countryside of Småland, in southern Sweden. He received most of his higher education at Uppsala University and began giving lectures in botany there in 1730. He lived abroad between 1735 and 1738, where he studied and also published the first edition of his ' in the Netherlands. He then returned to Sweden where he became professor of medicine and botany at Uppsala. In the 1740s, he was sent on several journeys through Sweden to find and classify plants and animals. In the 1750s and 1760s, he continued to collect an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphipod
Amphipoda is an order of malacostracan crustaceans with no carapace and generally with laterally compressed bodies. Amphipods range in size from and are mostly detritivores or scavengers. There are more than 9,900 amphipod species so far described. They are mostly marine animals, but are found in almost all aquatic environments. Some 1,900 species live in fresh water, and the order also includes the terrestrial sandhoppers such as ''Talitrus saltator''. Etymology and names The name ''Amphipoda'' comes, via New Latin ', from the Greek roots 'on both/all sides' and 'foot'. This contrasts with the related Isopoda, which have a single kind of thoracic leg. Particularly among anglers, amphipods are known as ''freshwater shrimp'', ''scuds'', or ''sideswimmers''. Description Anatomy The body of an amphipod is divided into 13 segments, which can be grouped into a head, a thorax and an abdomen. The head is fused to the thorax, and bears two pairs of antennae and one pair of se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seagrass
Seagrasses are the only flowering plants which grow in marine environments. There are about 60 species of fully marine seagrasses which belong to four families (Posidoniaceae, Zosteraceae, Hydrocharitaceae and Cymodoceaceae), all in the order Alismatales (in the clade of monocotyledons). Seagrasses evolved from terrestrial plants which recolonised the ocean 70 to 100 million years ago. The name ''seagrass'' stems from the many species with long and narrow leaves, which grow by rhizome extension and often spread across large "meadows" resembling grassland; many species superficially resemble terrestrial grasses of the family Poaceae. Like all autotrophic plants, seagrasses photosynthesize, in the submerged photic zone, and most occur in shallow and sheltered coastal waters anchored in sand or mud bottoms. Most species undergo submarine pollination and complete their life cycle underwater. While it was previously believed this pollination was carried out without pollinators ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brackish
Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuaries, or it may occur in brackish fossil aquifers. The word comes from the Middle Dutch root '' brak''. Certain human activities can produce brackish water, in particular civil engineering projects such as dikes and the flooding of coastal marshland to produce brackish water pools for freshwater prawn farming. Brackish water is also the primary waste product of the salinity gradient power process. Because brackish water is hostile to the growth of most terrestrial plant species, without appropriate management it is damaging to the environment (see article on shrimp farms). Technically, brackish water contains between 0.5 and 30 grams of salt per litre—more often expressed as 0.5 to 30 parts per thousand (‰), which is a specific grav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypoxia (environmental)
Hypoxia refers to low oxygen conditions. Normally, 20.9% of the gas in the atmosphere is oxygen. The partial pressure of oxygen in the atmosphere is 20.9% of the total barometric pressure. In water, oxygen levels are much lower, approximately 7 ppm or 0.0007% in good quality water, and fluctuate locally depending on the presence of photosynthetic organisms and relative distance to the surface (if there is more oxygen in the air, it will diffuse across the partial pressure gradient). Atmospheric hypoxia Atmospheric hypoxia occurs naturally at high altitudes. Total atmospheric pressure decreases as altitude increases, causing a lower partial pressure of oxygen, which is defined as hypobaric hypoxia. Oxygen remains at 20.9% of the total gas mixture, differing from hypoxic hypoxia, where the percentage of oxygen in the air (or blood) is decreased. This is common in the sealed burrows of some subterranean animals, such as blesmols. Atmospheric hypoxia is also the basis of altitude tra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gulls
Gulls, or colloquially seagulls, are seabirds of the family Laridae in the suborder Lari. They are most closely related to the terns and skimmers and only distantly related to auks, and even more distantly to waders. Until the 21st century, most gulls were placed in the genus ''Larus'', but that arrangement is now considered polyphyletic, leading to the resurrection of several genera. An older name for gulls is mews, which is cognate with German ''Möwe'', Danish ''måge'', Swedish ''mås'', Dutch ''meeuw'', Norwegian ''måke''/''måse'' and French ''mouette'', and can still be found in certain regional dialects. Gulls are typically medium to large in size, usually grey or white, often with black markings on the head or wings. They typically have harsh wailing or squawking calls; stout, longish bills; and webbed feet. Most gulls are ground-nesting carnivores which take live food or scavenge opportunistically, particularly the ''Larus'' species. Live food often includes crustac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cormorants
Phalacrocoracidae is a family of approximately 40 species of aquatic birds commonly known as cormorants and shags. Several different classifications of the family have been proposed, but in 2021 the IOC adopted a consensus taxonomy of seven genera. The great cormorant (''Phalacrocorax carbo'') and the common shag (''Gulosus aristotelis'') are the only two species of the family commonly encountered in Britain and Ireland and "cormorant" and "shag" appellations have been later assigned to different species in the family somewhat haphazardly. Cormorants and shags are medium-to-large birds, with body weight in the range of and wing span of . The majority of species have dark feathers. The bill is long, thin and hooked. Their feet have webbing between all four toes. All species are fish-eaters, catching the prey by diving from the surface. They are excellent divers, and under water they propel themselves with their feet with help from their wings; some cormorant species have been f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terns
Terns are seabirds in the family Laridae that have a worldwide distribution and are normally found near the sea, rivers, or wetlands. Terns are treated as a subgroup of the family Laridae which includes gulls and skimmers and consists of eleven genera. They are slender, lightly built birds with long, forked tails, narrow wings, long bills, and relatively short legs. Most species are pale grey above and white below, with a contrasting black cap to the head, but the marsh terns, the Inca tern, and some noddies have dark plumage for at least part of the year. The sexes are identical in appearance, but young birds are readily distinguishable from adults. Terns have a non-breeding plumage, which usually involves a white forehead and much-reduced black cap. Terns are long-lived birds and are relatively free from natural predators and parasites; most species are declining in numbers due directly or indirectly to human activities, including habitat loss, pollution, disturbance, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Egrets
Egrets ( ) are herons, generally long-legged wading birds, that have white or buff plumage, developing fine plumes (usually milky white) during the breeding season. Egrets are not a biologically distinct group from herons and have the same build. Biology Many egrets are members of the genera ''Egretta'' or '' Ardea'', which also contain other species named as herons rather than egrets. The distinction between a heron and an egret is rather vague, and depends more on appearance than biology. The word "egret" comes from the French word ''aigrette'' that means both "silver heron" and "brush", referring to the long, filamentous feathers that seem to cascade down an egret's back during the breeding season (also called "egrets"). Several of the egrets have been reclassified from one genus to another in recent years; the great egret, for example, has been classified as a member of either ''Casmerodius'', ''Egretta'', or ''Ardea''. In the 19th and early part of the 20th centuries, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlantic Mackerel
The Atlantic mackerel (''Scomber scombrus''), also known as Boston mackerel, Norwegian mackerel, Scottish mackerel or just mackerel, is a species of mackerel found in the temperate waters of the Mediterranean Sea, the Black Sea, and the northern Atlantic Ocean, where it is extremely common and occurs in huge shoals in the epipelagic zone down to about . It spends the warmer months close to shore and near the ocean surface, appearing along the coast in spring and departing with the arrival of colder weather in the fall and winter months. During the fall and winter, it migrates out into deeper and more southern water, seeking warmer temperatures. The Atlantic mackerel's body is elongate, steel-blue marked with wavy black lines dorsally and silvery-white ventrally, its snout long and pointed. It possesses two spiny dorsal fins, which are spaced far apart, two pectoral fins, and small caudal and anal fins, also spaced far apart. 4-6 dorsal finlets and 5 anal finlets are typical among ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blue Fish
The bluefish (''Pomatomus saltatrix'') is the only extant species of the family Pomatomidae. It is a marine pelagic fish found around the world in temperate and subtropical waters, except for the northern Pacific Ocean. Bluefish are known as tailor in Australia and New Zealand, elf and shad in South Africa. It is a popular gamefish and food fish. The bluefish is a moderately proportioned fish, with a broad, forked tail. The spiny first dorsal fin is normally folded back in a groove, as are its pectoral fins. Coloration is a grayish blue-green dorsally, fading to white on the lower sides and belly. Its single row of teeth in each jaw is uniform in size, knife-edged, and sharp. Bluefish commonly range in size from seven-inch (18-cm) "snappers" to much larger, sometimes weighing as much as 40 lb (18 kg), though fish heavier than 20 lb (9 kg) are exceptional. Systematics The bluefish is the only extant species now included in the family Pomatomidae. At one ti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
