Ninespine stickleback | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Scorpaeniformes |
Family: | Gasterosteidae |
Genus: | Pungitius |
Species: | P. pungitius |
Binomial name | |
Pungitius pungitius | |
Synonyms [2] | |
|
The ninespine stickleback (Pungitius pungitius), also called the ten-spined stickleback, is a freshwater species of fish in the family Gasterosteidae that inhabits temperate waters. It is widely but locally distributed throughout Eurasia and North America. Despite its name, the number of spines can vary from 8 to 12.
The ninespine stickleback is a small fish, reaching a maximum size of around 12.5 cm. [3] It reaches an age of about 3 years. [3] The body of the ninespine stickleback tapers to a very narrow caudal peduncle and the caudal fin is fan-shaped. The body is less deep and more elongated than that of the three-spined stickleback with a thinner and longer caudal peduncle, but the best way of distinguishing these two species is the number of spines in front of the dorsal fin which, for this species, varies from seven to twelve although nine is the commonest number. This species does not have scales but there is a group of small bony plates on the narrowest part of the caudal peduncle at the lateral line. The mouth points upwards in this species. It is generally greyish or olive-brown with silvery flanks irregularly barred or blotched with darker colour. [4] During the breeding season, the males develop a black area around the pelvis and the pelvic spines become white. The eyes are dark with a gold ring around the pupils.
The ninespine stickleback lives in streams, lakes, ponds and rivers and favors thick submerged vegetation, as its small spines do not offer much protection. Like the three spined stickleback, they have a series of scutes or bony plates along the lateral line but, in freshwater populations, these are frequently reduced in number with a gap between the anterior and posterior plates.[ citation needed ]
The species occurs in freshwater systems draining into the Arctic Ocean and the Atlantic across Canada, Alaska, and south to New Jersey. It is present on the North American Pacific coast of Alaska and in the Great Lakes basin. It can also be found throughout most of Eurasia, including the United Kingdom, Greenland, Turkey and the Far East. [1]
During the breeding season (April to July), the male builds a nest suspended on a piece of waterweed, about an inch or so above the substrate at the bottom. The female is attracted by the male and she lays eggs inside the nest, but then departs, leaving parental care to the male. The male guards these eggs and the young fry when they hatch. Then, when they have their spines, he drives them away to look after themselves.
The ninespine stickleback is a euryhaline and eurythermal species of teleost fish, occupying both freshwater and marine habitats in higher latitudes of the world. Recently, this species has been under great examination due to pond populations' adaptations of morphology, life history, and behavior which separates them from their marine conspecifics. [5] Many recently isolated populations (<11,000 years) have been studied to identify ranges of phenotypic plasticity and possible genetic drift between populations. It has been found that marine populations exhibit metabolic rate reduction when in colder conditions, in addition to having an elevated hepatosomatic index (HSI) at all temperature conditions as compared to freshwater populations in those same conditions. Hepatosomatic index refers to the proportional size of the liver of the fish to its body mass, as in indication of energy reserves. In addition, certain freshwater pond populations have shown to be able to metabolically compensate to survive a wide range of temperatures, six degrees Celsius to nineteen degrees Celsius. Alterations to metabolic rate, such as decrease in standard metabolic rate, allowed pond population individuals to survive less than favorable conditions. Such physiological differences between populations has not been determined to be exclusively due to plasticity or generic changes; however, there has been found to be significant genetic diversity between marine and freshwater populations. [6]
Due to their climatic versatility, Ninespine Stickleback face much variation in dissolved oxygen in their environment. Ninespines are physoclists, so they lack a connection between their swim bladder and their digestive tract. [7] This means they cannot gulp air from the surface of the water, as physostome fish do, in order to compensate for an environment of low dissolved oxygen, hypoxia. Responses to hypoxia may include increased ventilation rate or slower gill perfusion. [8] Ninespines must rely solely on their gas secretion and absorption abilities, using aquatic surface respiration (ASR) when facing a hypoxic situation. Comparable physostomous fish could prevent ASR to an extent by gulping air, while Ninespines may only rely on only ASR when acclimating to hypoxic conditions. ASR is when the fish rise almost to the surface to ventilate with the top millimeter of water which is high in dissolved oxygen. Ninespine Stickleback do not regularly experience nocturnal hypoxia in their natural environments, and therefore, have slower and decreased control of their swim-bladder lift. Consequently, the Ninespines begin ASR at a much higher dissolved oxygen concentration in hypoxic environments, as compared to other stickleback species, such as the Brook Stickleback. [7]
The celebrated British zoologist Desmond Morris (born 1928) published a paper in 1952 — "Homosexuality in the ten-spined stickleback (Pygosteus pungitius L.)." [9] — which became the basis of his 1954 doctoral thesis at Oxford University. [10] (This work was undertaken under the tutelage of the famous ethologist Niko Tinbergen. [11] ) Morris described and illustrated the normal reproductive behavior of the stickleback as well as certain "pseudofemale" variants which he thought might be fairly frequent in occurrence. ("These observations reveal that the nervous mechanisms of the sexual behavior pattern of the other sex are present, although they are not normally functional.") Although these findings were considered fairly conventional at the time within his specialty, the topic represented a harbinger of the later controversy that Morris's popular publications would arouse when he extended the findings of the biological sciences to the interpretation of aspects of human behavior. He describes some of his adventures with the fish, and his roomful of aquaria, in his book Animal Days (1979).
Gasterosteoidei is a suborder of ray-finned fishes that includes the sticklebacks and relatives, the 5th edition of Fishes of the World classifies this suborder within the order Scorpaeniformes.
The sticklebacks are a family of ray-finned fishes, the Gasterosteidae which have a Holarctic distribution in fresh, brackish and marine waters. They were thought to be related to the pipefish and seahorses but are now thought to be more closely related to the eelpouts and sculpins.
The three-spined stickleback is a fish native to most inland and coastal waters north of 30°N. It has long been a subject of scientific study for many reasons. It shows great morphological variation throughout its range, ideal for questions about evolution and population genetics. Many populations are anadromous and very tolerant of changes in salinity, a subject of interest to physiologists. It displays elaborate breeding behavior and it can be social making it a popular subject of inquiry in fish ethology and behavioral ecology. Its antipredator adaptations, host-parasite interactions, sensory physiology, reproductive physiology, and endocrinology have also been much studied. Facilitating these studies is the fact that the three-spined stickleback is easy to find in nature and easy to keep in aquaria.
Dead zones are hypoxic (low-oxygen) areas in the world's oceans and large lakes. Hypoxia occurs when dissolved oxygen (DO) concentration falls to or below 2 mg of O2/liter. When a body of water experiences hypoxic conditions, aquatic flora and fauna begin to change behavior in order to reach sections of water with higher oxygen levels. Once DO declines below 0.5 ml O2/liter in a body of water, mass mortality occurs. With such a low concentration of DO, these bodies of water fail to support the aquatic life living there. Historically, many of these sites were naturally occurring. However, in the 1970s, oceanographers began noting increased instances and expanses of dead zones. These occur near inhabited coastlines, where aquatic life is most concentrated.
"Fixed action pattern" is an ethological term describing an instinctive behavioral sequence that is highly stereotyped and species-characteristic. Fixed action patterns are said to be produced by the innate releasing mechanism, a "hard-wired" neural network, in response to a sign/key stimulus or releaser. Once released, a fixed action pattern runs to completion.
The epaulette shark is a species of longtailed carpet shark of the family Hemiscylliidae, found in shallow, tropical waters off Australia and New Guinea. The common name of this shark comes from the very large, white-margined black spot behind each pectoral fin, which are reminiscent of military epaulettes. A small species usually under 1 m (3.3 ft) long, the epaulette shark has a slender body with a short head and broad, paddle-shaped paired fins. The caudal peduncle comprises over half the shark's length. Adults are light brown above, with scattered darker spots and indistinct saddles.
The brook stickleback is a small freshwater fish that is distributed across the US and Canada. It grows to a length of about 2 inches. It occupies the northern part of the eastern United States, as well as the southern half of Canada. Small populations are scattered throughout the Mississippi-Great Lakes basin extending to Colorado, New Mexico, Kentucky, Tennessee, etc., though some of these areas are not native to the species. This small fish inhabits clear, cool streams and lakes. They eat small invertebrates, algae, insect larvae, and occasionally their own eggs. They are also preyed upon by smallmouth bass and northern pike. Feeding time is usually dawn and sunset. The brook stickleback does have active competition mostly from minnows, but feeding times are different, along with diet. Spawning occurs in midsummer. Males secure a territory, build a nest, and mate with females. Males provide protection for the eggs, ward off predators, and usually die later in the season. This is considered an annual species. The nests are built out of aquatic grasses. Though the brook stickleback is not considered a threatened species, deforesting and changing waters are altering ecosystems of the species. Harvesting of trees around riparian environments is having a large effect of the stream ecosystem where the brook stickleback resides.
Pungitius hellenicus, the Greek ninespine stickleback or ellinopygósteos, is a species of fish in the family Gasterosteidae. It is endemic to Greece. Its natural habitats are rivers and freshwater spring. It is threatened by habitat loss and considered critically endangered in the International Red List of IUCN, Bern Convention.
Pungitius is a genus of sticklebacks.
The Ukrainian stickleback also known as the Caspian ninespine stickleback, southern ninespine stickleback, and Aral ninespine stickleback, is a species of fish in the family Gasterosteidae. It is found in Afghanistan, Bulgaria, Iran, Kazakhstan, Moldova, Romania, Russia, Serbia, Montenegro, and Ukraine.
The purple shore crab is a common crab of the family Varunidae that is indigenous to the west coast of United States, Canada, and Mexico. H. nudus was first described in 1847 by Adam White, and in 1851, James Dwight Dana formally classified the species. H. nudus is a small, amphibious crab that is similar physically and behaviorally to Pachygrapsus crassipes and Hemigrapsus oregonensis. The purple shore crab is generally a dark purple color with olive green, red, and white spots. Mating season for H. nudus begins in mid-winter and larval crabs undergo 5 zoeal stages and a juvenile stage. Adult crabs mainly feed on algae but will occasionally scavenge other animals. H. nudus prefers inter-tidal and sub-tidal zones, and it can oftentimes be found sheltering under rocks or other debris. H. nudus demonstrates complex compensatory mechanisms to counteract fluctuating salinity and water oxygen concentrations, permitting it to live in a variety of different environments.
Hypoxia refers to low oxygen conditions. For air-breathing organisms, hypoxia is problematic. But for many anaerobic organisms, hypoxia is essential. Hypoxia applies to many situations, but usually refers to the atmosphere and natural waters.
Spinachia is a monospecific genus of ray-finned fish belonging to the family Gasterosteidae, the sticklebacks. The only species in the genus is Spinachia spinachia, the sea stickleback, fifteen-spined stickleback or fifteenspine stickleback, a species which lives in benthopelagic and in brackish environments of the northeastern Atlantic Ocean. This species, the largest of the sticklebacks, grows to a length of 22 centimetres (8.7 in) SL. This species is the only known member of its genus Spinachia. It is of no interest as a commercial fish.
Apeltes is a monospecific genus old ray-finned fish belonging to the family Gasterosteidae, the sticklebacks. The only species in the genus is Apeltes quadracus, the fourspine stickleback or bloody stickleback, which lives in freshwater, brackish and benthopelagic environments of the northwestern Atlantic Ocean between Newfoundland and South Carolina.
Fish are exposed to large oxygen fluctuations in their aquatic environment since the inherent properties of water can result in marked spatial and temporal differences in the concentration of oxygen. Fish respond to hypoxia with varied behavioral, physiological, and cellular responses to maintain homeostasis and organism function in an oxygen-depleted environment. The biggest challenge fish face when exposed to low oxygen conditions is maintaining metabolic energy balance, as 95% of the oxygen consumed by fish is used for ATP production releasing the chemical energy of nutrients through the mitochondrial electron transport chain. Therefore, hypoxia survival requires a coordinated response to secure more oxygen from the depleted environment and counteract the metabolic consequences of decreased ATP production at the mitochondria.
The Gulf killifish is one of the largest members of the genus Fundulus; it is capable of growing up to 7 inches (18 cm) in length, whereas the majority of other Fundulus reach a maximum length of 4 inches (10 cm). Therefore, F. grandis is among the largest minnows preyed upon by many sport fish, such as flounder, speckled trout, and red drum. Fundulus derives from the Latin meaning "bottom," and grandis means "large". The Gulf killifish is native to the Gulf of Mexico from Texas to Florida and the eastern coast of Florida and the Caribbean Sea in the Atlantic Ocean. Threats to the survival of the Gulf killifish include extreme changes in salinity, changes in temperatures, and toxic events such as the hypoxic dead zone in Louisiana and the Deepwater Horizon oil spill. The Gulf killifish is currently being used to test the effects of oil and oil dispersants on the physiology of marine species affected by these substances. This is significant to conservation biology, because with the continued extraction of oil and other natural resources from North American waters, it has become increasingly important to understand the risks and consequences in worst-case scenarios, such as the Deepwater Horizon oil spill, and the lasting effects on the marine ecosystem.
Pungitius laevis, commonly known as smoothtail ninespine stickleback, is a species of freshwater fish of the family Gasterosteidae. It is distributed in temperate brackish benthopelagic waters of coastal western Europe.
Gasterosteus nipponicus is a species of ray-finned fish belonging to the family Gasterosteidae, the sticklebacks. This species is found in the northwestern Pacific Ocean.
Astyanax abramis is a small freshwater fish from the inland rivers of South America. It is plentiful in almost the entire continent, with a habitat including the La Plata, upper Amazon, and Meta River basins. The body shape is subrhomboidal and laterally compressed, and the scales are largely silver, with a blue or green tint on the dorsal side.