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93-498: The Alamitos Creek banks were inhabited by Native American tribes thousands of years ago and up until the time of Spanish exploration . Evidence of middens and traces of that hunter-gatherer civilization has been recorded from archeological excavations and surface finds. From the mid-19th century until the 1970s, operation of the New Almaden Quicksilver Mines discharged high levels of mercury into

186-600: A regional accent , with urban mallards in London being much louder and more vociferous compared to rural mallards in Cornwall , serving as an adaptation to persistent levels of anthropogenic noise. When incubating a nest, or when offspring are present, females vocalise differently, making a call that sounds like a truncated version of the usual quack. This maternal vocalisation is highly attractive to their young. The repetition and frequency modulation of these quacks form

279-816: A speculum on their wings; males especially tend to have blue speculum feathers. The mallard is 50–65 cm (20–26 in) long, of which the body makes up around two-thirds the length. The wingspan is 81–98 cm (32–39 in) and the bill is 4.4 to 6.1 cm (1.7 to 2.4 in) long. It is often slightly heavier than most other dabbling ducks, weighing 0.7–1.6 kg (1.5–3.5 lb). Mallards live in wetlands , eat water plants and small animals, and are social animals preferring to congregate in groups or flocks of varying sizes. The female lays 8 to 13 creamy white to greenish-buff spotless eggs , on alternate days. Incubation takes 27 to 28 days and fledging takes 50 to 60 days. The ducklings are precocial and fully capable of swimming as soon as they hatch. The mallard

372-630: A system of classification for societies in all human cultures, based on the evolution of social inequality and the role of the state . This system of classification contains four categories: Tribes are therefore considered to be a political unit formed from an organisation of families (including clans and lineages) based on social or ideological solidarity. Membership of a tribe may be understood as being based on factors such as kinship ("clan"), ethnicity ("race"), language, dwelling place, political group, religious beliefs, oral tradition and/or cultural practices . Archaeologists continue to explore

465-695: A 'late' clutch occurred in November 2011, in which a female successfully hatched and raised a clutch of eleven ducklings at the London Wetland Centre . During the breeding season, both male and female mallards can become aggressive, driving off competitors to themselves or their mate by charging at them. Males tend to fight more than females and attack each other by repeatedly pecking at their rival's chest, ripping out feathers and even skin on rare occasions. Female mallards are also known to carry out 'inciting displays', which encourage other ducks in

558-609: A brood of ducklings. Nesting sites are typically on the ground, hidden in vegetation where the female's speckled plumage serves as effective camouflage , but female mallards have also been known to nest in hollows in trees, boathouses, roof gardens and on balconies, sometimes resulting in hatched offspring having difficulty following their parent to water. Egg clutches number 8–13 creamy white to greenish-buff eggs free of speckles. They measure about 58 mm (2.3 in) in length and 32 mm (1.3 in) in width. The eggs are laid on alternate days, and incubation begins when

651-426: A city-state, such a unit as Jericho might have become in its later stages … tribalism can be viewed as reaction to the formation of complex political structure rather than a necessary preliminary stage in its evolution. The term "tribe" was in common use in the field of anthropology until the late 1950s and 1960s. The continued use of the term has attracted controversy among anthropologists and other academics active in

744-492: A combination of hot temperatures and reduced water levels place mallards at an increased risk of contracting botulism , as these conditions are ideal for Clostridium botulinum to propagate, with the birds also more likely to come into contact with botulinum toxin produced by the bacteria. Outbreaks of botulism among mallard populations can lead to mass die-offs. The predation-avoidance behaviour of sleeping with one eye open, allowing one brain hemisphere to remain aware while

837-529: A darker crown and eye-stripe. Mallards, like other sexually-dimorphic birds, can sometimes go though spontaneous sex reversal, often caused by damaged or nonfunctioning sex organs, such as the ovaries in mallard hens. This phenomenon can cause female mallards to exhibit male plumage, and vice versa (phenotypic feminisation or masculinisation). Both male and female mallards have distinct iridescent purple-blue speculum feathers edged with white, which are prominent in flight or at rest but temporarily shed during

930-510: A few blood vessels to prevent heat loss, and, as in the Greenland mallard, the bill is smaller than that of birds farther south, illustrating the rule. Due to the variability of the mallard's genetic code, which gives it its vast interbreeding capability, mutations in the genes that decide plumage colour are very common and have resulted in a wide variety of hybrids, such as Brewer's duck (mallard × gadwall, Mareca strepera ). The mallard

1023-436: A few mammals on the lower reaches such as raccoon . Vegetation includes upland tree species such as coast live oak and California bay laurel ; understory growth such as coyote brush , toyon and poison oak ; and riparian vegetation such as red willow and wild blackberry . In the extreme downstream reaches rufous-crowned sparrow , California thrasher and American kestrel can be observed on chaparral slopes. In

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1116-669: A few metres deep. They are attracted to bodies of water with aquatic vegetation. The mallard is omnivorous and very flexible in its choice of food. Its diet may vary based on several factors, including the stage of the breeding cycle, short-term variations in available food, nutrient availability, and interspecific and intraspecific competition . The majority of the mallard's diet seems to be made up of gastropods , insects (including beetles, flies, lepidopterans , dragonflies , and caddisflies ), crustaceans , other arthropods , worms, feces of other birds, many varieties of seeds and plant matter, and roots and tubers . During

1209-404: A glass window. This paper was awarded an Ig Nobel Prize in 2003. Mallards are opportunistically targeted by brood parasites , occasionally having eggs laid in their nests by redheads , ruddy ducks , lesser scaup , gadwalls , northern shovellers , northern pintails , cinnamon teal , common goldeneyes , and other mallards. These eggs are generally accepted when they resemble the eggs of

1302-547: A large warm lake area difficult for trout to migrate through. Santa Clara Valley Water District is in the process of separating the creek from the lake to address these problems, expecting to be done in 2022. After it exits the lake, Alamitos Creek is joined by Guadalupe Creek . This confluence is the origin of the Guadalupe River mainstem, just east of Almaden Expressway and north of Coleman Road. Alamitos Creek once supported runs of steelhead. In July and August 1997,

1395-505: A leadership responsive to the needs of neighboring states (the so-called tribes of the United States or British India provide good examples of this). The British favored the label "aboriginal tribe" for some communities. India adopted a republican constitution in 1950, after three years of debate in its Constituent Assembly. During the debate, Jaipal Singh, a member of Munda tribe from Central India advocated for special provisions for

1488-448: A lineage or clan , but smaller than a chiefdom , ethnicity , nation or state . These terms are similarly disputed. In some cases tribes have legal recognition and some degree of political autonomy from national or federal government, but this legalistic usage of the term may conflict with anthropological definitions. In the United States, Native American tribes are legally considered to have "domestic dependent nation" status within

1581-562: A location along Alamitos Creek about .6 mile below the confluence with Arroyo Calero . Alamitos Creek drains an area of approximately 38 square miles (98 km), and begins at the base of Almaden Reservoir , although the reservoir is fed by Herbert Creek whose source is just south of the peak of Mount Umunhum . In addition to Herbert Creek, the reservoir has several minor tributaries including Barret Creek, Jacques Gulch, and Larrabee Creek. Barret Creek begins in Barret Canyon draining

1674-447: A mallard) to huge bald ( Haliaeetus leucocephalus ) and golden eagles ( Aquila chrysaetos ), and about a dozen species of mammalian predators, not counting several more avian and mammalian predators who threaten eggs and nestlings. Mallards are also preyed upon by other waterside apex predators , such as grey herons ( Ardea cinerea ), great blue herons ( Ardea herodias ) and black-crowned night herons ( Nycticorax nycticorax ),

1767-434: A meadow once grazed by dairy cows into the lake. Mercury and Canada goose excrement pollute the lake so that it remains closed to the public. Lake Almaden is a great impediment to native steelhead trout ( Oncorhynchus mykiss ) migration, as it is home to many non-native predatory fish, such as largemouth bass ( Micropterus salmoides ). It also serves as a heat sink elevating river water temperatures downstream and creating

1860-579: A narrow crawl corridor below the Almaden Expressway bridge, hikers can continue by using sidewalks and the signalized intersection of Coleman Road/Almaden Expressway, trail users can follow the Guadalulpe Creek Trail westward to Meridian Avenue (unpaved, interim gravel surface). Tribe The term tribe is used in many different contexts to refer to a category of human social group . The predominant worldwide usage of

1953-541: A river bank, but not always near water. It is highly gregarious outside of the breeding season and forms large flocks , which are known as "sordes". Mallards usually form pairs (in October and November in the Northern Hemisphere) until the female lays eggs at the start of the nesting season, which is around the beginning of spring. At this time she is left by the male who joins up with other males to await

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2046-441: A separate subspecies, the Greenland mallard ( A.   p.   conboschas ). The mallard is a medium-sized waterfowl species that is often slightly heavier than most other dabbling ducks. It is 50–65 cm (20–26 in) long – of which the body makes up around two-thirds – has a wingspan of 81–98 cm (32–39 in), and weighs 0.7–1.6 kg (1.5–3.5 lb). Among standard measurements,

2139-432: A sequence of 2-10 quacks in a row, starting loud and with the volume gradually decreasing. Male mallards make a sound phonetically similar to that of the female, a typical quack , but it is deeper and quieter compared to that of the female. Research conducted by Middlesex University on two English mallard populations found that the vocalisations of the mallard varies depending on their environment and have something akin to

2232-466: A severe threat to indigenous waterfowl's genetic integrity. Mallards and their hybrids compete with indigenous birds for resources, including nest sites, roosting sites, and food. Availability of mallards, mallard ducklings, and fertilised mallard eggs for public sale and private ownership, either as poultry or as pets, is currently legal in the United States, except for the state of Florida , which has currently banned domestic ownership of mallards. This

2325-777: A strong flavour. They were first domesticated in Southeast Asia at least 4,000 years ago, during the Neolithic Age , and were also farmed by the Romans in Europe, and the Malays in Asia . As the domestic duck and the mallard are the same species as each other, it is common for mallards to mate with domestic ducks and produce hybrid offspring that are fully fertile. Because of this, mallards have been found to be contaminated with

2418-588: A verbal root meaning 'to be'. Latin tribus is held to derive from the Proto-Indo-European compound * tri-dʰh₁u/o- ('rendered in three, tripartite division'; compare with Umbrian trifu 'trinity, district', Sanskrit trídha 'threefold'). Considerable debate has accompanied efforts to define and characterize tribes. In the popular imagination, tribes reflect a primordial social structure from which all subsequent civilizations and states developed. Anthropologist Elman Service presented

2511-418: A very small and fluctuating population. Mallards sometimes arrive on its island home during migration, and can be expected to occasionally have remained and hybridised with Laysan ducks as long as these species have existed. However, these hybrids are less well adapted to the peculiar ecological conditions of Laysan Island than the local ducks, and thus have lower fitness . Laysan ducks were found throughout

2604-518: A white square on the wings in flight, and is a smaller bird. More similar to the female mallard in North America are the American black duck ( A.   rubripes ), which is notably darker-hued in both sexes than the mallard, and the mottled duck ( A.   fulvigula ), which is somewhat darker than the female mallard, and with slightly different bare-part colouration and no white edge on

2697-605: Is a dabbling duck that breeds throughout the temperate and subtropical Americas , Eurasia , and North Africa . It has been introduced to New Zealand, Australia, Peru, Brazil, Uruguay, Argentina, Chile, Colombia, the Falkland Islands, and South Africa. This duck belongs to the subfamily Anatinae of the waterfowl family Anatidae . Males (drakes) have green heads, while the females (hens) have mainly brown-speckled plumage . Both sexes have an area of white-bordered black or iridescent purple or blue feathers called

2790-560: Is a paved, 4.7-mile (7.6 km) pedestrian and bicycle trail that runs along Alamitos Creek, from Harry Road (south) to Lake Almaden Park (north). As the trail crosses beneath the Coleman Road bridge, it meets the confluence of Guadalupe Creek and becomes the Guadalupe River Trail . A paved trail system which continues along the Guadalupe River extending northward to Chynoweth Avenue. As an alternative to walking under

2883-676: Is considered to be a species of least concern by the International Union for Conservation of Nature (IUCN). Unlike many waterfowl, mallards are considered an invasive species in some regions. It is a very adaptable species, being able to live and even thrive in urban areas which may have supported more localised, sensitive species of waterfowl before development. The non-migratory mallard interbreeds with indigenous wild ducks of closely related species through genetic pollution by producing fertile offspring. Complete hybridisation of various species of wild duck gene pools could result in

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2976-478: Is currently introgressing into the mallard populations of the Primorsky Krai , possibly due to habitat changes from global warming . The Mariana mallard was a resident allopatric population – in most respects a good species – apparently initially derived from mallard-Pacific black duck hybrids; it became extinct in the late 20th century. The Laysan duck is an insular relative of the mallard, with

3069-420: Is more a consequence of local ducks declining than of mallards spreading; allopatric speciation and isolating behaviour have produced today's diversity of mallard-like ducks despite the fact that, in most, if not all, of these populations, hybridisation must have occurred to some extent. Mallards are causing severe "genetic pollution" to South Africa's biodiversity by breeding with endemic ducks even though

3162-635: Is not warranted a vulnerable rating. Also, the population size of the mallard is very large. Unlike many waterfowl, mallards have benefited from human alterations to the world – so much so that they are now considered an invasive species in some regions. They are a common sight in urban parks, lakes, ponds, and other human-made water features in the regions they inhabit, and are often tolerated or encouraged in human habitat due to their placid nature towards humans and their beautiful and iridescent colours. While most are not domesticated, mallards are so successful at coexisting in human regions that

3255-526: Is sometimes still used this way. It was derived from the Old French malart or mallart for "wild drake" although its true derivation is unclear. It may be related to, or at least influenced by, an Old High German masculine proper name Madelhart , clues lying in the alternative English forms "maudelard" and "mawdelard". Masle (male) has also been proposed as an influence. Mallards frequently interbreed with their closest relatives in

3348-600: Is to prevent hybridisation with the native mottled duck . The mallard is considered an invasive species in Australia and New Zealand, where it competes with the Pacific black duck (known as the grey duck locally in New Zealand) which was over-hunted in the past. There, and elsewhere, mallards are spreading with increasing urbanisation and hybridising with local relatives. The eastern or Chinese spot-billed duck

3441-712: Is widely distributed across the Northern and Southern Hemispheres; in North America its range extends from southern and central Alaska to Mexico, the Hawaiian Islands , across the Palearctic , from Iceland and southern Greenland and parts of Morocco ( North Africa ) in the west, Scandinavia and Britain to the north, and to Siberia, Japan, and South Korea. Also in the east, it ranges to south-eastern and south-western Australia and New Zealand in

3534-586: The Agreement on the Conservation of African-Eurasian Migratory Waterbirds – an agreement to protect the local waterfowl populations – applies to the mallard as well as other ducks. The hybrids of mallards and the yellow-billed duck are fertile, capable of producing hybrid offspring. If this continues, only hybrids occur and in the long term result in the extinction of various indigenous waterfowl. The mallard can crossbreed with 63 other species, posing

3627-785: The D-loop sequence suggest that mallards may have evolved in the general area of Siberia . Mallard bones rather abruptly appear in food remains of ancient humans and other deposits of fossil bones in Europe , without a good candidate for a local predecessor species . The large Ice Age palaeosubspecies that made up at least the European and West Asian populations during the Pleistocene has been named Anas platyrhynchos palaeoboschas . Mallards are differentiated in their mitochondrial DNA between North American and Eurasian populations, but

3720-584: The European herring gull ( Larus argentatus ), the wels catfish ( Silurus glanis ), and the northern pike ( Esox lucius ). Crows ( Corvus   spp. ) are also known to kill ducklings and adults on occasion. Also, mallards may be attacked by larger anseriformes such as swans ( Cygnus   spp. ) and geese during the breeding season, and are frequently driven off by these birds over territorial disputes. Mute swans ( Cygnus olor ) have been known to attack or even kill mallards if they feel that

3813-541: The Native American tribes of North America, tribes are considered sovereign nations , that have retained their sovereignty or been granted legal recognition by the federal government. Mallard A. p. platyrhynchos Linnaeus, 1758 A. p. domesticus Linnaeus, 1758 A. p. conboschas C. L. Brehm , 1831 (disputed) [REDACTED] The mallard ( / ˈ m æ l ɑːr d , ˈ m æ l ər d / ) or wild duck ( Anas platyrhynchos )

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3906-841: The Old World mallards and the New World mallard demonstrates the extent to which the genome is shared among them such that birds like the Chinese spot-billed duck are highly similar to the Old World mallard, and birds such as the Hawaiian duck are highly similar to the New World mallard. The size of the mallard varies clinally ; for example, birds from Greenland , though larger, have smaller bills, paler plumage, and stockier bodies than birds further south and are sometimes classified as

3999-570: The Santa Clara Valley Water District electrofished sites near Alamitos Creek's confluence with Golf Creek near the McKean Road crossing. In the downstream rocky streambed reaches of the creek there are a variety of birds commonly observed including mallard , black phoebe , common merganser , red-shouldered hawk , snowy egret , belted kingfisher , great blue heron and black-crowned night-heron . There are

4092-775: The genus Anas , such as the American black duck , and also with species more distantly related, such as the northern pintail , leading to various hybrids that may be fully fertile. The mallard has hybridised with more than 40 species in the wild, and an additional 20 species in captivity, though fertile hybrids typically have two Anas parents. Mallards and their domestic conspecifics are fully interfertile; many wild mallard populations in North America contain significant amounts of domestic mallard DNA. Genetic analysis has shown that certain mallards appear to be closer to their Indo-Pacific relatives, while others are related to their American relatives. Mitochondrial DNA data for

4185-466: The oak woodlands along the creek, acorn woodpecker , California quail , Anna's hummingbird , scrub jay , oak titmouse , bushtit , Bewick's wren , and spotted towhee can be found. The California Office of Environmental Health Hazard Assessment has issued a "Do Not Eat" for any fish caught in Alamitos Creek due to elevated mercury. The Los Alamitos Creek Trail or Alamitos Creek Trail

4278-723: The social sciences with scholars of anthropological and ethnohistorical research challenging the utility of the concept. In 1970, anthropologist J. Clyde Mitchell wrote: Despite the membership boundaries for a tribe being conceptually simple, in reality they are often vague and subject to change over time. In his 1975 study, The Notion of the Tribe , Fried provided numerous examples of tribes that encompassed members who spoke different languages and practiced different rituals, or who shared languages and rituals with members of other tribes. Similarly, he provided examples of tribes in which people followed different political leaders, or followed

4371-402: The wing chord is 25.7 to 30.6 cm (10.1 to 12.0 in), the bill is 4.4 to 6.1 cm (1.7 to 2.4 in), and the tarsus is 4.1 to 4.8 cm (1.6 to 1.9 in). The breeding male mallard is unmistakable, with a glossy bottle-green head and a white collar that demarcates the head and neck from the purple-tinged brown breast, grey-brown wings, and a pale grey belly. The rear of

4464-464: The 'Adibasi' -- a translation into Hindi of 'aboriginal'. His arguments proved persuasive. These communities were to have seats in the legislatures and positions in government employment 'reserved' for them. Each of the assembly members prepared a list of communities that deserved special protections. These names were listed in a "Schedule" (appendix) to the Constitution. So these came to be called

4557-444: The 'Scheduled Tribes', often abbreviated to ST. Second, bands could form "secondary" tribes as a means to defend against state expansion. Members of bands would form more clearly bounded and centralized polities, because such polities could begin producing surpluses that could support a standing army that could fight against states, and they would have a leadership that could co-ordinate economic production and military activities. In

4650-489: The District developed a comprehensive flood control plan and retained Earth Metrics Inc. to prepare an independent Environmental Impact Report . The resulting study developed the first comprehensive data base of biology , water quality , geology and cultural resources information for Alamitos Creek. In 1989 the city of San Jose undertook an analysis to create a creekside trail from Almaden Quicksilver County Park to

4743-402: The Greenland mallard which is larger than the mallards further south. Allen's Rule says that appendages like ears tend to be smaller in polar forms to minimise heat loss, and larger in tropical and desert equivalents to facilitate heat diffusion, and that the polar taxa are stockier overall. Examples of this rule in birds are rare as they lack external ears, but the bill of ducks is supplied with

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4836-515: The Hawaiian archipelago before 400   AD, after which they suffered a rapid decline during the Polynesian colonisation. Now, their range includes only Laysan Island. It is one of the successfully translocated birds, after having become nearly extinct in the early 20th century. Mallards have often been ubiquitous in their regions among the ponds, rivers, and streams of human parks, farms, and other human-made waterways – even to

4929-526: The Southern hemisphere. It is strongly migratory in the northern parts of its breeding range, and winters farther south. For example, in North America, it winters south to the southern United States and northern Mexico , but also regularly strays into Central America and the Caribbean between September and May. A drake later named "Trevor" attracted media attention in 2018 when it turned up on

5022-460: The annual summer moult. Upon hatching, the plumage of the duckling is yellow on the underside and face (with streaks by the eyes) and black on the back (with some yellow spots) all the way to the top and back of the head. Its legs and bill are also black. As it nears a month in age, the duckling's plumage starts becoming drab, looking more like the female, though more streaked, and its legs lose their dark grey colouring. Two months after hatching,

5115-535: The auditory basis for species identification in offspring, a process known as acoustic conspecific identification. In addition, females hiss if the nest or offspring are threatened or interfered with. When taking off, the wings of a mallard produce a characteristic faint whistling noise. The mallard is a rare example of both Allen's Rule and Bergmann's Rule in birds. Bergmann's Rule, which states that polar forms tend to be larger than related ones from warmer climates, has numerous examples in birds, as in case of

5208-408: The beginning and the end of the summer moulting period. The adulthood age for mallards is fourteen months, and the average life expectancy is three years, but they can live to twenty. Several species of duck have brown-plumaged females that can be confused with the female mallard. The female gadwall ( Mareca strepera ) has an orange-lined bill, white belly, black and white speculum that is seen as

5301-400: The breeding season, male birds were recorded to have eaten 37.6% animal matter and 62.4% plant matter, most notably the grass Echinochloa crus-galli , and nonlaying females ate 37.0% animal matter and 63.0% plant matter, while laying females ate 71.9% animal matter and only 28.1% plant matter. Plants generally make up the larger part of a bird's diet, especially during autumn migration and in

5394-455: The centre tail feather (drake feather) is curled, but in females, the centre tail feather is straight. During the final period of maturity leading up to adulthood (6–10 months of age), the plumage of female juveniles remains the same while the plumage of male juveniles gradually changes to its characteristic colours. This change in plumage also applies to adult mallard males when they transition in and out of their non-breeding eclipse plumage at

5487-841: The clutch is almost complete. Incubation takes 27–28   days and fledging takes 50–60   days. The ducklings are precocial and fully capable of swimming as soon as they hatch. However, filial imprinting compels them to instinctively stay near the mother, not only for warmth and protection but also to learn about and remember their habitat as well as how and where to forage for food. Though adoptions are known to occur, female mallards typically do not tolerate stray ducklings near their broods, and will violently attack and drive away any unfamiliar young, sometimes going as far as to kill them. When ducklings mature into flight-capable juveniles, they learn about and remember their traditional migratory routes (unless they are born and raised in captivity). In New Zealand, where mallards are naturalised ,

5580-659: The creek near its headwaters and the remaining piles of exposed mine tailings still contaminate the creek beyond natural levels. Warning signs to not eat fish caught in the Alamitos Creek still run the length of its course. In the 1940s and 1950s, rapid residential development expanded into this portion of the Almaden Valley including building which encroached into the 100-year floodplain . The Santa Clara Valley Water District began studying this watershed with emphasis upon flood control functions, and made some minor streambed alterations such as energy dissipators . In 1976

5673-458: The development of pre-state tribes. Current research suggests that tribal structures constituted one type of adaptation to situations providing plentiful yet unpredictable resources. Such structures proved flexible enough to coordinate production and distribution of food in times of scarcity, without limiting or constraining people during times of surplus. Anthropologist Morton Fried argued in 1967 that bands organized into tribes in order to resist

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5766-480: The ducks pose a threat to their offspring. Common loons ( Gavia inmer ) are similarly territorial and aggressive towards other birds in such disputes, and will frequently drive mallards away from their territory. However, in 2019, a pair of common loons in Wisconsin were observed raising a mallard duckling for several weeks, having seemingly adopted the bird after it had been abandoned by its parents. In summer,

5859-436: The extinction of many indigenous waterfowl. The mallard itself is the ancestor of most domestic ducks, and its naturally evolved wild gene pool gets genetically polluted in turn by the domestic and feral populations. Over time, a continuum of hybrids ranging between almost typical examples of either species develop; the speciation process is beginning to reverse itself. This has created conservation concerns for relatives of

5952-463: The extinction of many indigenous waterfowl. This species is the main ancestor of most breeds of domestic duck , and its naturally evolved wild gene pool has been genetically polluted by the domestic and feral mallard populations. The mallard was one of the many bird species originally described in the 1758 10th   edition of Systema Naturae by Carl Linnaeus . He gave it two binomial names : Anas platyrhynchos and Anas boschas . The latter

6045-423: The female. Lebret (1961) calls this behaviour "Attempted Rape Flight", and Stanley Cramp and K.E.L. Simmons (1977) speak of "rape-intent flights". Male mallards also occasionally chase other male ducks of a different species, and even each other, in the same way. In one documented case of "homosexual necrophilia", a male mallard copulated with another male he was chasing after the chased male died upon flying into

6138-414: The fledgling period has ended, and the duckling is now a juvenile. The duckling is able to fly 50–60 days after hatching. Its bill soon loses its dark grey colouring, and its sex can finally be distinguished visually by three factors: 1)   the bill is yellow in males, but black and orange in females; 2)   the breast feathers are reddish-brown in males, but brown in females; and 3)   in males,

6231-408: The flock to begin fighting. It is possible that this behaviour allows the female to evaluate the strength of potential partners. The drakes that end up being left out after the others have paired off with mating partners sometimes target an isolated female duck, even one of a different species, and proceed to chase and peck at her until she weakens, at which point the males take turns copulating with

6324-564: The form is a result of borrowing directly from Latin (the Middle English plural tribuz 1250 may be a direct representation of Latin plural tribūs ). Modern English tribe may also be a result of a common pattern wherein English borrows nouns directly from Latin and drops suffixes, including -us . Latin tribus is generally held by linguists to be a compound formed from two elements: tri- 'three' and bhu , bu , fu ,

6417-402: The genes of the domestic duck. While the keeping of domestic breeds is more popular, pure-bred mallards are sometimes kept for eggs and meat, although they may require wing clipping to restrict flying. Mallards are one of the most common species shot in waterfowl hunting due to their large population size. The ideal location for hunting mallards is considered to be where the water level

6510-420: The host mallard, but the hen may attempt to eject them or even abandon the nest if parasitism occurs during egg laying. In addition to human hunting, mallards of all ages (but especially young ones) and in all locations must contend with a wide diversity of predators including raptors and owls , mustelids , corvids , snakes , raccoons , opossums , skunks , turtles , large fish , felids , and canids ,

6603-493: The hundreds,” said Vice President Marti Tedesco of the Peninsula Open Space Trust. Downstream of Almaden Reservoir, Alamitos Creek has another major tributary, Arroyo Calero . Arroyo Calero's upstream reach was dammed to form Calero Reservoir . Alamitos Creek feeds into Lake Almaden (not to be confused with Almaden Reservoir ). Lake Almaden was formed by a private gravel quarry operation which changed

6696-507: The island of Niue , an atypical location for mallards. The mallard inhabits a wide range of habitats and climates, from the Arctic tundra to subtropical regions. It is found in both fresh- and salt-water wetlands, including parks, small ponds, rivers, lakes and estuaries , as well as shallow inlets and open sea within sight of the coastline. Water depths of less than 0.9 metres (3.0 ft) are preferred, with birds avoiding areas more than

6789-472: The last two including domestic cats and dogs. The most prolific natural predators of adult mallards are red foxes ( Vulpes vulpes ; which most often pick off brooding females) and the faster or larger birds of prey, (e.g. peregrine falcons , Aquila or Haliaeetus eagles). In North America, adult mallards face no fewer than 15 species of birds of prey, from northern harriers ( Circus hudsonius ) and short-eared owls ( Asio flammeus ) (both smaller than

6882-734: The main conservation risk they pose comes from the loss of genetic diversity among a region's traditional ducks once humans and mallards colonise an area. Mallards are very adaptable, being able to live and even thrive in urban areas which may have supported more localised, sensitive species of waterfowl before development. The release of feral mallards in areas where they are not native sometimes creates problems through interbreeding with indigenous waterfowl . These non-migratory mallards interbreed with indigenous wild ducks from local populations of closely related species through genetic pollution by producing fertile offspring. Complete hybridisation of various species of wild duck gene pools could result in

6975-447: The male is black, with white-bordered dark tail feathers. The bill of the male is a yellowish-orange tipped with black, with that of the female generally darker and ranging from black to mottled orange and brown. The female mallard is predominantly mottled, with each individual feather showing sharp contrast from buff to very dark brown, a coloration shared by most female dabbling ducks, and has buff cheeks, eyebrow, throat, and neck, with

7068-494: The mallard species. Ecological changes and hunting have also led to a decline of local species; for example, the New Zealand grey duck population declined drastically due to overhunting in the mid-20th century. Hybrid offspring of Hawaiian ducks seem to be less well adapted to native habitat, and using them in re-introduction projects apparently reduces success. In summary, the problems of mallards "hybridising away" relatives

7161-549: The mallard, such as the Hawaiian duck , the New Zealand grey duck ( A.   s. superciliosa) subspecies of the Pacific black duck , the American black duck, the mottled duck , Meller's duck , the yellow-billed duck , and the Mexican duck , in the latter case even leading to a dispute as to whether these birds should be considered a species (and thus entitled to more conservation research and funding) or included in

7254-1280: The modern state system. Tribes have lost their legitimacy to conduct traditional functions, such as tithing , delivering justice and defending territory, with these being replaced by states functions and institutions, such as taxation, law courts and the military. Most have suffered decline and loss of cultural identity. Some have adapted to the new political context and transformed their culture and practices in order to survive, whilst others have secured legal rights and protections. Fried proposed that most surviving tribes do not have their origin in pre-state tribes, but rather in pre-state bands. Such "secondary" tribes, he suggested, developed as modern products of state expansion. Bands comprise small, mobile, and fluid social formations with weak leadership . They do not generate surpluses, pay no taxes, and support no standing army. Fried argued that secondary tribes develop in one of two ways. First, states could set them up as means to extend administrative and economic influence in their hinterland, where direct political control costs too much. States would encourage (or require) people on their frontiers to form more clearly bounded and centralized polities, because such polities could begin producing surpluses and taxes, and would have

7347-478: The moulting period, which begins in June (in the Northern Hemisphere). During the brief time before this, however, the males are still sexually potent and some of them either remain on standby to sire replacement clutches (for female mallards that have lost or abandoned their previous clutch) or forcibly mate with females that appear to be isolated or unattached regardless of their species and whether or not they have

7440-479: The nature, structure and practices of tribes. Writing on the Kurdish peoples, anthropologist Martin van Bruinessen argued, "the terms of standard anthropological usage, 'tribe', 'clan' and 'lineage' appear to be a straitjacket that ill fits the social reality of Kurdistan". There are further negative connotations of the term "tribe" that have reduced its use. Writing in 2013, scholar Matthew Ortoleva noted that "like

7533-444: The nesting season has been found to be longer, eggs and clutches are larger and nest survival is generally greater compared with mallards in their native range. In cases where a nest or brood fails, some mallards may mate for a second time in an attempt to raise a second clutch, typically around early-to-mid summer. In addition, mallards may occasionally breed during the autumn in cases of unseasonably warm weather; one such instance of

7626-896: The north slope of Loma Prieta, the tallest peak in the Santa Cruz Mountains, and joins Herbert Creek from the south just before joining Almaden Reservoir. Barret Creek gained significant protection in 2018 when the Peninsula Open Space Trust , the Santa Clara Valley Open Space Authority and the Midpeninsula Regional Open Space District purchased 500 acres of land to preserve as open space. “Rainbow trout in Barret Creek were [once] so plentiful that fishermen used to catch them by

7719-485: The nuclear genome displays a notable lack of genetic structure. Haplotypes typical of American mallard relatives and eastern spot-billed ducks can be found in mallards around the Bering Sea . The Aleutian Islands hold a population of mallards that appear to be evolving towards becoming a subspecies , as gene flow with other populations is very limited. Also, the paucity of morphological differences between

7812-510: The other half sleeps, was first demonstrated in mallards, although it is believed to be widespread among birds in general. Since 1998, the mallard has been rated as a species of least concern on the IUCN Red List of Endangered Species . This is because it has a large range–more than 20,000,000 km (7,700,000 mi ) and because its population is increasing, rather than declining by 30% over ten years or three generations and thus

7905-525: The point of visiting water features in human courtyards . Mallards have had a long relationship with humans. Almost all domestic duck breeds derive from the mallard, with the exception of a few Muscovy breeds, and are listed under the trinomial name A. p. domesticus . Mallards are generally monogamous while domestic ducks are mostly polygamous . Domestic ducks have no territorial behaviour and are less aggressive than mallards. Domestic ducks are mostly kept for meat; their eggs are also eaten, and have

7998-416: The same leaders as members of other tribes. He concluded that tribes in general are characterized by fluid boundaries, heterogeneity and dynamism, and are not parochial. Part of the difficulty with the term is that it seeks to construct and apply a common conceptual framework across diverse cultures and peoples. Different anthropologists studying different peoples therefore draw conflicting conclusions about

8091-406: The speculum. In captivity, domestic ducks come in wild-type plumages, white, and other colours. Most of these colour variants are also known in domestic mallards not bred as livestock, but kept as pets, aviary birds, etc., where they are rare but increasing in availability. A noisy species, the female has the deep quack stereotypically associated with ducks. The female will often call with

8184-458: The term in English is in the discipline of anthropology . Its definition is contested, in part due to conflicting theoretical understandings of social and kinship structures, and also reflecting the problematic application of this concept to extremely diverse human societies. The concept is often contrasted by anthropologists with other social and kinship groups, being hierarchically larger than

8277-490: The territorial United States, with a government-to-government relationship with the federal government. The modern English word tribe stems from Middle English tribu , which ultimately derives from Latin tribus . According to the Oxford English Dictionary , it remains unclear if this form is the result of a borrowing from a Romance language source (such as Old French tribu ) or if

8370-422: The violence and exploitation of early kingdoms and states. He wrote: In fact, there is no absolute necessity for a tribal stage as defined by Sahlins and Service, no necessity, that is, for such a stage to appear in the transit from a single settlement with embedded political organization, to a complex-state structured polity. Such a developmental process could have gone on within a unit that we may conceptualize as

8463-487: The winter. The mallard usually feeds by dabbling for plant food or grazing; there are reports of it eating frogs , other amphibians , and fish , including carcasses . However, in 2017 a flock of mallards in Romania were observed hunting small migratory birds, including grey wagtails and black redstarts , the first documented occasion they had been seen attacking and consuming large vertebrates. It usually nests on

8556-415: The word Indian , [t]ribe is a word that has connotations of colonialism." Survival International says "It is important to make the distinction between tribal and indigenous because tribal peoples have a special status acknowledged in international law as well as problems in addition to those faced by the wider category of indigenous peoples." Few tribes today remain isolated from the development of

8649-523: Was generally preferred until 1906 when Einar Lönnberg established that A.   platyrhynchos had priority, as it appeared on an earlier page in the text. The scientific name comes from Latin Anas , "duck" and Ancient Greek πλατυρυγχος, platyrhynchus , "broad-billed" (from πλατύς, platys , "broad" and ρυγχός, rhunkhos , "bill"). The genome of Anas platyrhynchos was sequenced in 2013. The name mallard originally referred to any wild drake, and it

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