105-789: The Waiwhetū Stream is a small watercourse in Lower Hutt , in the North Island of New Zealand. The stream drains the eastern side of the Hutt Valley , and enters Wellington Harbour at the Hutt River estuary. Development and urbanisation of the Hutt Valley since the arrival of settlers led to increasing pollution and degradation of the stream environment. The stream was diverted into concrete culverts in some sections in an attempt to reduce flooding. Industrial development in
210-558: A diurnal cycle , becoming dark at day and pale at night. The skin also has photoreceptors , light sensitive cells, most of them concentrated in the tail, which helps them to stay buried. Lampreys may spend up to eight years as ammocoetes, while species such as the Arctic lamprey may only spend one to two years as larvae, prior to undergoing a metamorphosis which generally lasts 3–4 months, but can vary between species. While metamorphosing, they do not eat. The rate of water moving across
315-402: A notochord , dorsal hollow nerve cord , pharyngeal slits , pituitary gland / endostyle , and a post anal tail during the process of their development are considered to be chordates . Lampreys contain these characteristics that define them as chordates. Lamprey anatomy is very different based on what stage of development they are in. The notochord is derived from the mesoderm and is one of
420-401: A city it is New Zealand's sixth most populous , with a population of 115,500. The total area administered by the council is 376.4 km (145 sq mi) around the lower half of the Hutt Valley and along the eastern shores of Wellington Harbour , of which 78.54 km (30 sq mi) is urban. It is separated from the city of Wellington by the harbour, and from Upper Hutt by
525-715: A city. It incorporated Normandale in 1957. In 1987–1989 the New Zealand Government forced local authorities to consolidate, which led to Lower Hutt amalgamating with the adjacent Boroughs of Petone and Eastbourne and with the Wainuiomata District (which had its independence for barely a year), and to the abolition of the Hutt County Council. The area of Lower Hutt is covered by two general electorates ( Hutt South and Remutaka ) and by two Māori electorates ( Ikaroa-Rāwhiti in
630-498: A dark-colored back, which enables them to blend in with the ground below when seen from above by a predator. Their light-colored undersides allow them to blend in with the bright air and water above them if a predator sees them from below. Lamprey coloration can also vary according to the region and specific environment in which the species is found. Some species can be distinguished by their unique markings – for example, Geotria australis individuals display two bluish stripes running
735-417: A group of jawless fish comprising the order Petromyzontiformes / ˌ p ɛ t r oʊ m ɪ ˈ z ɒ n t ɪ f ɔːr m iː z / . The adult lamprey is characterized by a toothed, funnel-like sucking mouth. The common name "lamprey" is probably derived from Latin lampetra , which may mean "stone licker" ( lambere "to lick" + petra "stone"), though the etymology is uncertain. Lamprey
840-496: A major project to clean up the lower reaches. This project was declared complete in June 2010, after the removal of 56,000 tonnes of toxic waste. In 2010–2011, a community group was formed to lead restoration of the upper reaches of the stream. Over a period of 10 years, volunteers cleared invasive aquatic weeds and rubbish from six kilometres (3.7 mi) of the stream bed and established around 34,000 locally sourced native plants on
945-411: A model system to work out the fundamental principles of motor control in vertebrates starting in the spinal cord and working toward the brain. In a series of studies by Rovainen and his student James Buchanan, the cells that formed the neural circuits within the spinal cord capable of generating the rhythmic motor patterns that underlie swimming were examined. Note that there are still missing details in
1050-399: A population density of 307 people per km . The city's population has remained stable from the 1990s to the 2013 census. In the five years between the 2013 and 2018 censuses, the population grew steadily across the city with an increasing amount of homes being purchased and the area seen as more affordable comparable to the rest of the region. Lower Hutt City had a population of 107,562 in
1155-587: A property advertisement in 1928, the Waiwhetū Stream was described as "the Avon of Wellington". In 1937, the committee managing Hutt Park considered a proposal to build a weir in the adjacent Waiwhetū Stream so that it could be used for bathing, even during low tide. In 1904, there was strong criticism of the Health Department for allowing the continuing discharge of sewage from thousands of patrons at
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#17327905380501260-404: A short section of the stream between Seaview Road and the rail bridge just north of Hutt Park Holiday Village. Local groups urged that a cleanup be undertaken. A major cleanup project commenced in 2009 to remove 12,000 cubic metres (420,000 cu ft) of contaminated mud from the lower reaches of the stream. The work was funded by Hutt City Council , Greater Wellington Regional Council and
1365-441: A single pair of regular eyes as well as two parietal eyes : a pineal and parapineal one (the exception is members of Mordacia ). The eyes of juvenile lampreys are poorly developed eyespot-like structures that are covered in non-transparent skin, while the eyes of adult lampreys are well developed. Accommodation is done by flattening the cornea, which pushes the lens towards the retina. The eye of family Mordaciidae possess just
1470-423: A single type of photoreceptor (rod-like), the family Petromyzontidae possess two photoreceptor types (a cone-like and a rod-like), and the family Geotriidae possesses five types of photoreceptors. The buccal cavity , anterior to the gonads , is responsible for attaching the animal, through suction, to either a stone or its prey. This then allows the tongue to make contact with the stone to rasp algae , or tear at
1575-446: A small number of radially arranged teeth, they lacked the specialised, heavily toothed discs with plate-like laminae present in modern lampreys, and it is possible that they fed by scraping algae off of animals, rather than feeding by predation/parasitism. They also lacked the modern three stage life cycle including ammocoetes found in modern lampreys, with the juvenile stages of these species closely resembling adults. Myxineidus from
1680-449: A sucking mouth. Those that are anadromous are carnivorous, feeding on fishes or marine mammals. Anadromous lampreys spend up to four years in the sea before migrating back to freshwater, where they spawn. Adults create nests (called redds ) by moving rocks, and females release thousands of eggs, sometimes up to 100,000. The male, intertwined with the female, fertilizes the eggs simultaneously. Being semelparous , both adults die after
1785-537: A typical repair time of 1 week, leading to repeated discharges of treated wastewater into the Waiwhetū Stream. Options presented to the Hutt City and Upper Hutt councils included refurbishment of the existing pipeline, or the construction of a new pipeline in Wellington Harbour. The forecast costs of a new outfall pipeline were approximately $ 700 million, with a further $ 300 million required for upgrades to
1890-571: Is also often simply called "the Hutt". Before European settlement, thick forest covered most of the Hutt Valley, with areas of marshland close to the river's mouth. Māori inhabited the shoreline, with a pā at each end of Petone beach. Māori welcomed the arrival of the New Zealand Company ship Tory in 1839, and William Wakefield (the company's agent) negotiated with some local chiefs to allow settlement. The first immigrant ship,
1995-415: Is anterior to the intestines. It contains the sinus , one atrium , and one ventricle protected by the pericardial cartilages. The pineal gland , a photosensitive organ regulating melatonin production by capturing light signals through the photoreceptor cell converting them into intercellular signals of the lamprey is located in the midline of its body, for lamprey, the pineal eye is accompanied by
2100-489: Is around nine kilometres (5.6 mi) in length and passes through the eastern suburbs of Fairfield , Waterloo , and Waiwhetū , and the industrial areas of Seaview and Gracefield before entering the estuary of the Hutt River Te Awa Kairangi as it reaches Wellington Harbour . The stream was traditionally a food source for local Māori , providing whitebait , eels and watercress . Prior to
2205-549: Is sometimes seen for the plural form. There are about 38 known extant species of lampreys and around seven known extinct species. They are classified in three families: two small families in the Southern Hemisphere ( Geotriidae , Mordaciidae ) and one large family in the Northern Hemisphere ; ( Petromyzontidae ). Genetic evidence suggests that lampreys are more closely related to hagfish ,
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#17327905380502310-534: Is still visible, notably at Hutt Central School. On New Year's Day 1859 the first permanent lighthouse to be built in New Zealand was lit at Pencarrow Head. New Zealand's only female lighthouse keeper, Mary Jane Bennett , became the inaugural operator of the lighthouse. The railway line from central Wellington reached Lower Hutt station (subsequently Western Hutt ) in April 1874, with the line running north up
2415-502: The 1855 Wairarapa earthquake , vessels large enough for coastal trade could navigate the lower reaches of the Waiwhetū stream, and there were several shipyards. One shipyard was located close to where Whites Line East crosses the stream. However, the earthquake raised the level of the valley floor by 1.5 metres (4 ft 11 in), and the stream was no longer navigable. Early plans by European settlers migrating to New Zealand included
2520-802: The 2018 census , and an increase of 9,213 people (9.5%) since the 2013 census . There were 52,563 males, 53,505 females and 465 people of other genders in 38,895 dwellings. 3.9% of people identified as LGBTIQ+ . The median age was 37.4 years (compared with 38.1 years nationally). There were 20,415 people (19.2%) aged under 15 years, 19,740 (18.5%) aged 15 to 29, 50,733 (47.6%) aged 30 to 64, and 15,642 (14.7%) aged 65 or older. People could identify as more than one ethnicity. The results were 64.1% European ( Pākehā ); 19.7% Māori ; 12.3% Pasifika ; 18.7% Asian ; 2.1% Middle Eastern, Latin American and African New Zealanders (MELAA); and 2.0% other, which includes people giving their ethnicity as "New Zealander". English
2625-818: The 2023 New Zealand census , an increase of 3,030 people (2.9%) since the 2018 census , and an increase of 9,324 people (9.5%) since the 2013 census . There were 53,082 males, 54,009 females and 468 people of other genders in 39,279 dwellings. 3.8% of people identified as LGBTIQ+ . The median age was 37.5 years (compared with 38.1 years nationally). There were 20,595 people (19.1%) aged under 15 years, 19,896 (18.5%) aged 15 to 29, 51,261 (47.7%) aged 30 to 64, and 15,807 (14.7%) aged 65 or older. People could identify as more than one ethnicity. The results were 64.3% European ( Pākehā ); 19.6% Māori ; 12.2% Pasifika ; 18.6% Asian ; 2.1% Middle Eastern, Latin American and African New Zealanders (MELAA); and 2.1% other, which includes people giving their ethnicity as "New Zealander". English
2730-708: The Aurora , arrived on 22 January 1840, an event still commemorated every year on the Monday closest as Wellington's Anniversary Day . A settlement, Britannia, grew up close to the mouth of the Hutt River ( Te Awa Kairangi in Māori language), and settlers set up New Zealand's first newspaper and bank. The city takes its name from the English name given to the river, named after one of the founding members, director and chairman of
2835-645: The Middle Jurassic and the end of the Cretaceous . Modern lampreys spend the majority of their life in the juvenile "ammocoete" stage, where they burrow into the sediment and filter feed . Adult carnivorous lampreys are the most well-known species, and feed by boring into the flesh of other fish (or in rare cases marine mammals) to consume flesh and/or blood ; but only 18 species of lampreys engage in this predatory lifestyle (with Caspiomyzon suggested to feed on carrion rather than live prey ). Of
2940-578: The Ministry for the Environment , and cost over $ 20 million. At the time, the stream was described as one of the country's most polluted waterways. The cleanup was declared complete in June 2010, after the removal of 56,000 tonnes of toxic waste. In 2010–2011, a volunteer group of residents was formed as the Friends of Waiwhetū Stream to act as guardians and take action to restore the upper reaches of
3045-646: The Māori language means "river of food from the sky". Lower Hutt occupies the lower regions of the flood plain of the river, one of the most significant features of the city. In the 20th century the Hutt River Board built stopbanks to contain the river, but the threat of flooding from heavy rainfall persists. In 1985 the river burst its banks, and since then floods have been on a smaller scale. Smaller streams and storm-water drains have also caused occasional problems when rainfall exceeds average levels. Much of
3150-577: The Remutaka Range . Lower Hutt's boundaries also include the islands in Wellington Harbour, the largest of which is Matiu / Somes Island . Lower Hutt has a wet oceanic climate ( Köppen climate classification : Cfb ), which is similar to nearby Wellington, with relatively warm summers and mild winters with the occasional storm. A single major aquifer dominates the lower Hutt Valley: the river , originally named Heretaunga, and since 2010 known as "Te Awa Kairangi / Hutt River". Awakairangi in
3255-456: The T cells and B cells present in higher vertebrates immune system. Pouched lamprey ( Geotria australis ) larvae also have a very high tolerance for free iron in their bodies, and have well-developed biochemical systems for detoxification of the large quantities of these metal ions. The adults spawn in nests of sand, gravel and pebbles in clear streams. After hatching from the eggs, young larvae—called ammocoetes —will drift downstream with
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3360-529: The otic vesicle . The lamprey has been extensively studied because its relatively simple brain is thought in many respects to reflect the brain structure of early vertebrate ancestors. Beginning in the 1970s, Sten Grillner and his colleagues at the Karolinska Institute in Stockholm followed on from extensive work on the lamprey started by Carl Rovainen in the 1960s that used the lamprey as
3465-403: The pharyngeal slits , are openings found between the pharynx or throat. Pharyngeal slits are filter feeding organs that help the movement of water through the mouth and out of these slits when feeding. During the lamprey's larval stage they feed by filter feeding. Once lampreys reach their adult phase they become parasitic on other fish, and these gill slits become very important in aiding in
3570-400: The phylum Chordata , which also includes the invertebrate subphyla Tunicata (sea-squirts) and the fish-like Cephalochordata ( lancelets or Amphioxus). Recent molecular and morphological phylogenetic studies place lampreys and hagfish in the infraphylum Agnatha or Agnathostomata (both meaning without jaws). The other vertebrate infraphylum is Gnathostomata (jawed mouths) and includes
3675-605: The 11th-century Norman Conquest of England, lampreys were found as far upstream in the River Thames as Petersham . The reduction of pollution in the Thames and River Wear has led to recent sightings in London and Chester-le-Street . Distribution of lampreys may also be adversely affected by dams and other construction projects due to disruption of migration routes and obstruction of access to spawning grounds. Conversely,
3780-543: The 18 carnivorous species, nine migrate from saltwater to freshwater to breed (some of them also have freshwater populations), and nine live exclusively in freshwater. All non-carnivorous forms are freshwater species. Adults of the non-carnivorous species do not feed; they live on reserves acquired as ammocoetes. Lampreys live mostly in coastal and fresh waters and are found in most temperate regions. Some species (e.g. Geotria australis , Petromyzon marinus , and Entosphenus tridentatus ) travel significant distances in
3885-1072: The 20th century, both names were used indiscriminately, even by the same author in subsequent publications. In the mid-1970s, the ICZN was called upon to fix one name or the other, and after much debate had to resolve the issue by voting. Thus, in 1980, the spelling with a "t" won out, and in 1981, it became official that all higher-level taxa based on Petromyzon have to start with "Petromyzont-". Phylogeny based on Brownstein & Near, 2023. Geotria Gray 1851 (pouched lampreys) Mordacia Gray 1853 (southern topeyed lampreys) Caspiomyzon Berg 1906 Petromyzon Linnaeus 1758 ( Sea lamprey ) Ichthyomyzon Girard 1858 Entosphenus Gill 1863 Tetrapleurodon Creaser & Hubbs 1922 (Mexican lampreys) Western American " Lampetra " Lethenteron Creaser & Hubbs 1922 Eudontomyzon Regan 1911 Lampetra sensu stricto Bonnaterre 1788 (Eastern American and European Lampetra ) Recent studies differ regarding
3990-571: The Carboniferous of France, often considered to be a hagfish , has been found to be a lamprey in some studies. The earliest lamprey with the specialised toothed oral disc typical of modern lampreys is Yanliaomyzon from the Middle Jurassic of China around 163 million years old, which is thought to have had a predatory lifestyle like modern lampreys, and probably had a three stage life cycle including ammocoetes. Mesomyzon from
4095-472: The Early Cretaceous of China, which displays the three stage life cycle with ammocoetes, was found in one study to be more closely related to the family Petromyzonidae than to other living lampreys, though other studies have found it to be outside the group containing all living lampreys. Synapomorphies are certain characteristics that are shared over evolutionary history. Organisms possessing
4200-505: The Hutt City Council commissioned a mosaic mural that celebrates the return of flora and fauna following the restoration of the stream. Prior to 2001, wastewater from the entire Hutt Valley was screened and then pumped without any further treatment via a pipeline along the eastern coastline of Wellington Harbour to an ocean outfall near the harbour entrance at Pencarrow Head . By the 1990s, the discharge of untreated sewage into
4305-608: The Hutt Park racecourse into the lower reaches of the Waiwhetū Stream. There were reports of illegal dumping into the Waiwhetū Stream as early as 1928. In 1926, the Government accepted tenders for the construction of new railway workshops in an industrial area close to the Waiwhetū Stream. In April 1929, the Lower Hutt Borough Council made a provision of £6,250 for the construction of septic tanks near
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4410-470: The Hutt River, in what is now Alicetown , formed the village then known as Aglionby. In 1846 conflict arose between European settlers and Māori , which led to armed conflict in the Hutt Valley Campaign . The 1855 Wairarapa earthquake (in the range of magnitude 8.1 to 8.3) raised part of the lower valley, allowing reclamation of land from swamp. The fault escarpment from the earthquake
4515-527: The New Zealand Company, Sir William Hutt . The dual name of Hutt River Te Awa Kairangi has been used since 2010. Within weeks of settlement the Hutt River flooded, and in March 1840 the majority of Britannia settlers decided to move to Thorndon , (as of 2013 in the heart of Wellington city), though some settlers remained at the north end of the harbour. In the 1840s an area on the west bank of
4620-690: The Seaview treatment plant, including a replacement sludge drier. 41°13′16″S 174°55′26″E / 41.221°S 174.924°E / -41.221; 174.924 Lower Hutt Lower Hutt ( Māori : Te Awa Kairangi ki Tai ) is a city in the Wellington Region of New Zealand. Administered by the Hutt City Council , it is one of the four cities that constitute the Wellington metropolitan area . If considered
4725-732: The Southern Hemisphere. It is thought that most modern lamprey diversity emerged during the Cenozoic, particularly within the last 10–20 million years. The oldest fossil lamprey, Priscomyzon , is known from the latest Devonian of South Africa around 360 million years ago, with other stem-group lampreys, like Pipiscius , Mayomyzon and Hardistiella known from the Carboniferous of North America. These Paleozoic stem-lampreys are small relative to modern lampreys, and while they had well developed oral discs with
4830-618: The Taita Gorge. Lower Hutt is unique among New Zealand cities, as the name of the council does not match the name of the city it governs. Special legislation has since 1991 given the council the name "Hutt City Council", while the name of the place itself remains "Lower Hutt City". This name has led to confusion, as Upper Hutt is administered by a separate city council, the Upper Hutt City Council. The entire Hutt Valley includes both Lower and Upper Hutt cities. Lower Hutt
4935-473: The Taitā Gorge at the northern end of Lower Hutt, separating the city from neighbouring Upper Hutt. Lower Hutt includes the cluster of small settlements that extend down the eastern coast of Wellington Harbour . These include the two large townships of Wainuiomata and Eastbourne . The city also includes a large area of sparsely-populated land to the east of the harbour, extending to Pencarrow Head and into
5040-612: The World classifies lampreys within the Class Petromyzontida, a taxon called Petromyzonti in Eschmeyer's Catalog of Fishes . The debate about their systematics notwithstanding, lampreys constitute a single order Petromyzontiformes . Sometimes still seen is the alternative spelling "Petromyzoniformes" , based on the argument that the type genus is Petromyzon and not "Petromyzonta" or similar. Throughout most of
5145-643: The algal blooms as the cause of death of a small number of dogs swimming in the river, as well as of skin reactions in the case of swimmers. Seven bridges cross the Hutt River within the city of Lower Hutt, with several other bridges built and replaced from the 1850s onwards. Tributaries of the Hutt River within Lower Hutt include: Here are listed the following suburbs of Lower Hutt City (unofficial suburbs are in italics ). Notes: Lower Hutt City covers 376.40 km (145.33 sq mi) and had an estimated population of 115,500 as of June 2024, with
5250-473: The ammocoetes' feeding apparatus is the lowest recorded in any suspension feeding animal, and they therefore require water rich in nutrients to fulfill their nutritional needs. While the majority of (invertebrate) suspension feeders thrive in waters containing under 1 mg suspended organic solids per litre (<1 mg/L), ammocoetes demand minimum 4 mg/L, with concentrations in their habitats having been measured up to 40 mg/L. During metamorphosis
5355-408: The animal attach itself to its prey. Made of keratin and other proteins, lamprey teeth have a hollow core to give room for replacement teeth growing under the old ones. Some of the original blood-feeding forms have evolved into species that feed on both blood and flesh, and some who have become specialized to eat flesh and may even invade the internal organs of the host. Tissue feeders can also involve
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#17327905380505460-449: The area around the lower reaches of the stream led to that section becoming an industrial sewer. Discharges of industrial waste into the lower reaches ceased in the 1980s when trade wastes were connected to piped sewer mains. However, the stream remained highly polluted with toxic sediments. In 2010, the stream was described as one of the most polluted waterways in New Zealand. Pressure from the community beginning around 2003 helped to trigger
5565-498: The area. The consent was opposed by the Friends of Waiwhetū Stream and local Māori. In March 2022, Wellington Water reported a leak in the pipeline to the outfall, in the Seaview area. Repairs required the shutdown of the pipeline, and the discharge of fully treated wastewater into Waiwhetū Stream while the repairs were carried out. In September 2023, Wellington Water predicted that pipeline shutdowns for repairs will become increasingly frequent, possibly rising to 30 times per year, with
5670-621: The banks of the stream. Waiwhetū means "star reflecting water" in Māori , and is the name given to the original pā site in the area, the local marae , the suburb, and the stream. Waiwhetū Stream is an official name recognised by the New Zealand Geographic Board . The stream has its headwaters in the Eastern Hutt hills, above the suburbs of Wingate and Naenae in Lower Hutt. It has a catchment area of around 18 square kilometres (6.9 sq mi). The stream
5775-568: The body, which pull rather than push their bodies through the water. Different species of lamprey have many shared physical characteristics. The same anatomical structure can serve different functions in the lamprey depending on whether or not it is carnivorous . The mouth and suction capabilities of the lamprey not only allow it to cling to a fish as a parasite , but provide it with limited climbing ability so that it can travel upstream and up ramps or rocks to breed. This ability has been studied in an attempt to better understand how lampreys battle
5880-425: The census question. Of those at least 15 years old, 19,026 (22.1%) people had a bachelor's or higher degree, 41,766 (48.5%) had a post-high school certificate or diploma, and 19,980 (23.2%) people exclusively held high school qualifications. The median income was $ 47,800, compared with $ 41,500 nationally. 12,957 people (15.0%) earned over $ 100,000 compared to 12.1% nationally. The employment status of those at least 15
5985-425: The census question. Of those at least 15 years old, 19,188 (22.1%) people had a bachelor's or higher degree, 42,231 (48.6%) had a post-high school certificate or diploma, and 20,148 (23.2%) people exclusively held high school qualifications. The median income was $ 47,800, compared with $ 41,500 nationally. 13,125 people (15.1%) earned over $ 100,000 compared to 12.1% nationally. The employment status of those at least 15
6090-596: The classes Chondrichthyes (sharks), Osteichthyes (bony fishes), Amphibia , Reptilia , Aves , and Mammalia . Some researchers have classified lampreys as the sole surviving representatives of the Linnean class Cephalaspidomorphi . Cephalaspidomorpha is sometimes given as a subclass of the Cephalaspidomorphi. Fossil evidence now suggests lampreys and cephalaspids acquired their shared characters by convergent evolution . The 5th edition of Fishes of
6195-431: The closure of the trade waste discharges from the industries in the area, the river was still highly polluted with toxic sediments. Mud in the stream bed down to a depth of 1.5 metres (4 ft 11 in) was heavily contaminated with lead, zinc, DDT and hydrocarbons including diesel, oil and petrol. In 2003, it was estimated that there was 30,000 cubic metres (1,100,000 cu ft) of heavily contaminated sediment in
6300-537: The construction of artificial channels has exposed new habitats for colonisation, notably in North America where sea lampreys have become a significant introduced pest in the Great Lakes . Active control programs to control lampreys are undergoing modifications due to concerns of drinking water quality in some areas. Adults superficially resemble eels in that they have scaleless , elongated bodies, with
6405-421: The construction of the weir in the stream. A particularly large eel weighing almost 11 kilograms (25 lb) was caught in the stream in 1876. The Acclimatisation Society liberated perch into the Waiwhetū Stream in 1913. An unusual catch was made in 1924 with the capture of a lamprey in the stream. In 1906, a newspaper featured photographs of picturesque scenes on the upper reaches of the Waiwhetū Stream. In
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#17327905380506510-502: The current and move forward despite only being able to hold onto the rock at a single point. Some scientists are also hoping to design ramps that will optimize the lamprey's climbing ability, as lampreys are valued as food in the Northwest United States and need to travel upstream to reproduce. Many lampreys exhibit countershading , a form of camouflage . Similarly to many other aquatic species, most lampreys have
6615-429: The current till they reach soft and fine sediment in silt beds, where they will burrow in silt, mud and detritus, taking up an existence as filter feeders, collecting detritus, algae, and microorganisms. The eyes of the larvae are underdeveloped, but are capable of discriminating changes in illuminance. Ammocoetes can grow from 3–4 inches (8–10 centimetres) to about 8 inches (20 cm). Many species change color during
6720-410: The defining characteristics of a chordate. The notochord provides signaling and mechanical cues to help the organism when swimming. The dorsal nerve cord is another characteristic of lampreys that defines them as chordates. During development this part of the ectoderm rolls creating a hollow tube. This is often why it is referred to as the dorsal "hollow" nerve cord. The third chordate feature, which are
6825-421: The eggs are fertilized. Research on sea lampreys has revealed that sexually mature males use a specialized heat-producing tissue in the form of a ridge of fat cells near the anterior dorsal fin to stimulate females. After having attracted a female with pheromones, the heat detected by the female through body contact will encourage spawning. Taxonomists place lampreys and hagfish in the subphylum Vertebrata of
6930-411: The establishment of a new town, to be called Britannia, that would be located in the Hutt Valley bounded by the hills to the west, and the Waiwhetū Stream to the east, with Hutt River running through the middle. However, these plans were changed within a short time, after a large flood in the Hutt River persuaded the settlers that the town should be located at the opposite side of the harbour. This new town
7035-492: The flesh of their prey to yield blood. The last common ancestor of lampreys appears to have been specialized to feed on the blood and body fluids of other fish after metamorphosis. They attach their mouthparts to the target animal's body, then use three horny plates (laminae) on the tip of their piston-like tongue, one transversely and two longitudinally placed, to scrape through surface tissues until they reach body fluids. The teeth on their oral disc are primarily used to help
7140-470: The highest number of chromosomes (164–174) among vertebrates. Due to certain peculiarities in their adaptive immune system , the study of lampreys provides valuable insight into the evolution of vertebrate adaptive immunity. Generated from a somatic recombination of leucine-rich repeat gene segments, lamprey leukocytes express surface variable lymphocyte receptors (VLRs). This convergently evolved characteristic allows them to have lymphocytes that work as
7245-428: The jaws of juvenile lampreys, a muscular flap-like structure called the velum is present, which serves to generate a water current towards the mouth opening, which enables feeding and respiration. The unique morphological characteristics of lampreys, such as their cartilaginous skeleton , suggest they are the sister taxon (see cladistics ) of all living jawed vertebrates ( gnathostomes ). They are usually considered
7350-515: The lamprey loses both the gallbladder and the biliary tract , and the endostyle turns into a thyroid gland. Some species, including those that are not carnivorous and do not feed even following metamorphosis, live in freshwater for their entire lifecycle, spawning and dying shortly after metamorphosing. In contrast, many species are anadromous and migrate to the sea, beginning to prey on other animals while still swimming downstream after their metamorphosis provides them with eyes, teeth, and
7455-720: The land adjacent to the river is protected as reserve by the City Council and managed by the Greater Wellington Regional Council to provide popular recreational areas. From the river mouth, walking and cycling trails and grassed areas occur at various points along both sides of the river up the Hutt Valley to Te Mārua , 28 km further north in Upper Hutt. With lower river-levels in mid-summer, algal blooms have contributed to making slow-flowing areas anoxic. The Regional Council has cited
7560-436: The largest species, the sea lamprey having a maximum body length of around 1.2 metres (3.9 ft). Lacking paired fins , adult lampreys have one nostril atop the head and seven gill pores on each side of the head. The brain of the lamprey is divided into the telencephalon , diencephalon , midbrain , cerebellum , and medulla . Lampreys have been described as the only living vertebrates to have four eyes, having
7665-444: The length of its body as an adult. These markings can also sometimes be used to determine what stage of the life cycle the lamprey is in; G. australis individuals lose these stripes when they approach the reproductive phase and begin to travel upstream. Another example is Petromyzon marinus , which shifts to more of an orange color as it reaches the reproductive stage in its life cycle. Northern lampreys ( Petromyzontidae ) have
7770-414: The main line between Lower Hutt and Petone. Two years later the railway workshops moved from Petone to a new larger site off the new branch at Woburn . In the late 1940s new suburbs of state housing developed along the eastern side of the Hutt Valley, from Waiwhetū to Taitā (then known as Taita), to alleviate nationwide housing shortages and to cater for the booming population . Between 1946 and 1954
7875-468: The most basal group of the Vertebrata . Instead of true vertebrae, they have a series of cartilaginous structures called arcualia arranged above the notochord. Hagfish , which resemble lampreys, have traditionally been considered the sister taxon of the true vertebrates (lampreys and gnathostomes) but DNA evidence suggests that they are in fact the sister taxon of lampreys. The heart of the lamprey
7980-473: The north and Te Tai Tonga in the south). The city centres on the lower southern valley of the Hutt River , to the northeast of the city of Wellington . The valley widens into a delta as the river nears its mouth, so the central urban area of the city forms a triangle with its longest side along the shoreline. In the upper reaches of the city the Western and Eastern Hutt Hills become closer, culminating in
8085-405: The ocean had become environmentally unacceptable. Planning for a new sewage treatment plan began in the mid 1990s. In 1998, tenders were called for a design, build and operate contract for a treatment plant to be built in Seaview that would provide secondary treatment of all sewage from the Hutt Valley and Wainuiomata. It was to be located close to the Waiwhetū Stream. A contract was let in 1999, and
8190-466: The only other living group of jawless fish, than they are to jawed vertebrates , forming the superclass Cyclostomi . The oldest fossils of stem-group lampreys are from the latest Devonian Period , around 360 million years ago, with modern looking forms only appearing during the Jurassic Period , around 163 million years ago, with the modern families likely splitting from each sometime between
8295-408: The open ocean, as evidenced by their lack of reproductive isolation between populations. Other species are found in land-locked lakes. Their larvae ( ammocoetes ) have a low tolerance for high water temperatures, which may explain why they are not distributed in the tropics. Lamprey distribution may be adversely affected by river habitat loss, overfishing and pollution. In Britain, at the time of
8400-413: The outlet of the Waiwhetū Stream. In 1936, an abatement notice was issued to the flock mill to cease the discharge of dust into the stream. In 1936, 1937 and 1938, there were multiple complaints from the caretaker of Hutt Park and the Hutt River Board's engineer that the stream was being polluted by a continuing discharge of oil from the railway workshops. By 1938, children were forbidden from swimming in
8505-511: The outlet of the stream. In 1931, the Hutt River Board reported that it had spent £1,000 in the previous 12 months on dredging the Waiwhetū Stream. In 1935, the Hutt Park committee received support from the Department of Lands and Survey for a project to plant trees on either side of Waiwhetū Stream in the vicinity of Hutt Park. The lower reaches of the stream had been used as an industrial sewer. In 2001, despite 20 years having passed since
8610-488: The parapineal organ. One of the key physical components to the lamprey are the intestines , which are located ventral to the notochord . Intestines aid in osmoregulation by intaking water from its environment and desalinating the water they intake to an iso-osmotic state with respect to blood, and are also responsible for digestion . Studies have shown that lampreys are among the most energy-efficient swimmers. Their swimming movements generate low-pressure zones around
8715-442: The plant was commissioned in 2001. In 2011, the Hutt City Council sought a 35 year consent for temporary discharges of treated effluent directly into the Waiwhetū Stream. These discharges would be required when maintenance was required on the main outfall pipeline. The temporary discharges cause pollution in the lower reaches of Waiwhetū Stream and in the estuary of the Hutt River, making it unsafe to collect shellfish, fish or swim in
8820-539: The railway line from Waterloo extended through these new suburbs to Haywards , becoming the main line in 1954 when the existing main line between Haywards and Melling closed. By the end of the 1950s, Lower Hutt had a population of 80,000. The Hutt City Council comprises a mayor and 12 councillors. Campbell Barry became New Zealand's youngest mayor and was first elected in 2019, succeeding Ray Wallace . The city's six electoral wards (Northern, Western, Central, Eastern, Harbour and Wainuiomata) each elect one councillor, with
8925-445: The remaining six councillors elected at-large. Mayor and councillors elected in the 2022 local-body elections: Neighbouring councils are Wellington City Council (adjoining to the west), Porirua City Council to the north, Upper Hutt City Council to the north-east and South Wairarapa District Council to the east. The boundaries of the Lower Hutt city local body have evolved from a series of amalgamations and boundary changes over
9030-425: The respiration of the organism. The final chordate synapomorphy is the post anal tail, which is muscular and extends behind the anus. Oftentimes adult amphioxus and lamprey larvae are compared by anatomists due to their similarities. Similarities between adult amphioxus and lamprey larvae include a pharynx with pharyngeal slits, a notochord, a dorsal hollow nerve cord and a series of somites that extend anterior to
9135-419: The river had shown that there are no longer any Cape pond weed plants present. The group also controls other invasive plants on the banks of the stream such as tradescantia and blackberry , and contributes to surveys of fish and invertebrates in the stream. Over the period from 2011 to 2021, volunteers planted 34,000 eco-sourced plants, along six kilometres (3.7 mi) of the stream's banks. In April 2019,
9240-544: The stream, with the support of the Greater Wellington Regional Council and Hutt City Council. One of the early tasks undertaken was the removal of the invasive aquatic plant Cape pond weed that had smothered the stream and impeded water flows. Over a period of three years, volunteers removed by hand approximately 300,000 plants from 3.4 kilometres (2.1 mi) of the stream. In 2023, the Friends of Waiwhetū Stream reported that annual sweeps of
9345-458: The stream. Development in the Hutt Valley and urbanisation led to clearing of vegetation on the banks of the stream, and changes to its natural contours. It became polluted and was affected by illegal rubbish dumping. The lower reaches were polluted with industrial discharges, including dyes from an adjacent carpet factory. In 1972, the stream caught fire because of the quantity of solvents that were being discharged. A Waiwhetū Stream Working Group
9450-796: The studios were eventually sold off in 2012 to a consortium of Wellington investors. Avalon continues to operate independently with seven film and television studios used as primarily as a feature film production base. A large proportion of Lower Hutt's residents commute to the mainly commercial, service and government offices in Wellington City 12 km to the south-west. The Civil Aviation Authority of New Zealand (CAA) has its headquarters in Aviation House in Petone , Lower Hutt. Lamprey Lampreys / ˈ l æ m p r eɪ z / (sometimes inaccurately called lamprey eels ) are
9555-441: The teeth on the oral disc in the excision of tissue. As a result, the flesh-feeders have smaller buccal glands as they do not require the production of anticoagulant continuously and mechanisms for preventing solid material entering the branchial pouches, which could otherwise potentially clog the gills. A study of the stomach content of some lampreys has shown the remains of intestines, fins and vertebrae from their prey. Close to
9660-543: The timing of the last common ancestor of all living lampreys, with some suggesting a Middle Jurassic date, around 175 million years ago, while other studies have suggested a younger split, dating to the Late Cretaceous. The older date study posited that the Northern and Southern Hemisphere lampreys diverged as part of the breakup of Pangea , while the Late Cretaceous study suggested that modern lampreys emerged in
9765-564: The west side of the Hutt River to Silverstream opening two years later. Before the Second World War of 1939–1945, urban settlement in the lower Hutt Valley concentrated mainly on Petone , central Lower Hutt and Eastbourne, with a total population of 30,000. In 1927 the Public Works Department completed the construction of a branch railway line to Waterloo on the east side of the river; the route diverging from
9870-567: The world. Over the past 25 years service, distribution, and consumer-oriented sectors have increased. Lower Hutt remains the main location for light industrial activity in the Wellington Region. Until post-war housing development took over, the central and northern areas of the city were largely market gardens. In 2010 the lower reaches of the Waiwhetū Stream was cleaned up to remove toxins from decades of industry use. The channel
9975-561: The years. The Hutt County Council , established in 1877, covered the region from Wellington's south coast up to Waikanae , excluding the Wellington City Council area. As the region grew, urban parts of the Hutt County became autonomous boroughs: Petone in 1888, Lower Hutt in 1891, Eastbourne in 1906, Johnsonville in 1908, Upper Hutt in 1908, Porirua in 1962 and Kapiti in 1974. In 1941 Lower Hutt became
10080-681: Was also widened to better protect against floods and native plantings and management has seen native waterlife and birds return to their habitat. Petone's Jackson Street and neighbouring areas have seen a resurgence in to one of Wellington's most popular retail and hospitality area. Lower Hutt has one of the greatest proportion of science, technology and high value manufacturing businesses in New Zealand. Crown research institute GNS Science and New Zealand's innovation centre and business accelerator Callaghan Innovation are based in Lower Hutt, along with over 800 research organisations in high-end manufacturing, research and technology. The suburb of Avalon
10185-462: Was another emergency discharge of sewage from a pumping station into the stream, leading to protests from local Māori. The Hutt River Board called tenders in November 1925 for clearing the upper reaches of the stream. In 1928, the Hutt River Board agreed to the clearing of the stream between the road bridge and the outlet. Later in 1929, the Hutt River Board commenced work on deepening and clearing
10290-524: Was established in 1898 in Fairfield, adjacent to the Waiwhetū Stream at the intersection of what is now Rumgay Street and Riverside Drive. It used a weir in the stream and a breastshot water wheel as a source of mechanical power. The flock mill operated for around 50 years, but was the subject of litigation in 1909–1910 that was heard in the Supreme Court over the effects of the flooding caused by
10395-521: Was formed in 2000 to advocate for the restoration of the stream. In 2003, a report on the state of the environment published by Greater Wellington Regional Council listed Waiwhetū Stream as one of the five most polluted streams in the region. In July 2021, the stream was polluted with the discharge of untreated sewage from pumping stations for a short period following exceptionally heavy rainfall. During another heavy rainfall event in December 2021, there
10500-507: Was home to New Zealand's television industry from 1975 until the late 1980s. The Avalon film and television studios were New Zealand's first purpose-built television studios, and is the largest television studio complex in Australasia. The studios were home to Television One from 1975 to 1980, when it merged with South Pacific Television to form Television New Zealand (TVNZ). After 1989 most of TVNZ's operations moved to Auckland, and
10605-557: Was spoken by 95.1%, Māori language by 5.1%, Samoan by 4.2% and other languages by 17.8%. No language could be spoken by 2.3% (e.g. too young to talk). New Zealand Sign Language was known by 0.6%. The percentage of people born overseas was 27.6, compared with 28.8% nationally. Religious affiliations were 33.9% Christian , 4.5% Hindu , 1.4% Islam , 1.1% Māori religious beliefs , 1.3% Buddhist , 0.4% New Age , 0.1% Jewish , and 1.8% other religions. People who answered that they had no religion were 49.6%, and 6.1% of people did not answer
10710-557: Was spoken by 95.1%, Māori language by 5.1%, Samoan by 4.3% and other languages by 17.9%. No language could be spoken by 2.3% (e.g. too young to talk). New Zealand Sign Language was known by 0.6%. The percentage of people born overseas was 27.7, compared with 28.8% nationally. Religious affiliations were 34.0% Christian , 4.5% Hindu , 1.4% Islam , 1.1% Māori religious beliefs , 1.3% Buddhist , 0.4% New Age , 0.1% Jewish , and 1.8% other religions. People who answered that they had no religion were 49.4%, and 6.1% of people did not answer
10815-573: Was that 47,736 (55.4%) people were employed full-time, 10,263 (11.9%) were part-time, and 2,679 (3.1%) were unemployed. Historically, Petone, Seaview and Gracefield have been the main area for industry in the Wellington region, with industries including meat processing and freezing, motor vehicle assembly, and timber processing. As business have taken advantage of global manufacturing efficiencies, much of this large scale industry has changed to smaller design-led and medium-sized industries exporting to
10920-422: Was that 48,201 (55.4%) people were employed full-time, 10,395 (12.0%) were part-time, and 2,694 (3.1%) were unemployed. Lower Hutt's urban area covers 78.54 km (30.32 sq mi) and had an estimated population of 114,500 as of June 2024, with a population density of 1,458 people per km . Lower Hutt had a population of 106,530 in the 2023 New Zealand census , an increase of 2,985 people (2.9%) since
11025-522: Was to be called Wellington. From the earliest times of colonial settlement, the Waiwhetū Stream was the source of occasional floods that caused stock losses and damage to property. Heavy rain in July 1912 and August 1928 led to the Waiwhetū Stream overflowing its banks and flooding the nearby Hutt Park and surrounding area. Residents living close to the stream were required to evacuate their homes on 15 November 2016 because of high flood levels. A flock mill
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