American white ibis
The American white ibis is a species of bird in the ibis family, Threskiornithidae. It is found from Virginia via the Gulf Coast of the United States south through most of the coastal New World tropics; this particular ibis is a medium-sized bird with an overall white plumage, bright red-orange down-curved bill and long legs, black wing tips that are only visible in flight. Males have longer bills than females; the breeding range runs along the Gulf and Atlantic Coast, the coasts of Mexico and Central America. Outside the breeding period, the range extends further inland in North America and includes the Caribbean, it is found along the northwestern South American coastline in Colombia and Venezuela. Populations in central Venezuela interbreed with the scarlet ibis; the two have been classified by some authorities as a single species. Their diet consists of small aquatic prey, such as insects and small fishes. Crayfish are its preferred food in most regions, but it can adjust its diet according to the habitat and prey abundance.
Its main foraging behavior is probing with its beak at the bottom of shallow water to feel for and capture its prey. It does not see the prey. During the breeding season, the American white ibis gathers in huge colonies near water. Pairs are predominantly monogamous and both parents care for the young, although males tend to engage in extra-pair copulation with other females to increase their reproductive success. Males have been found to pirate food from unmated females and juveniles during the breeding season. Human pollution has affected the behavior of the American white ibis via an increase in the concentrations of methylmercury, released into the environment from untreated waste. Exposure to methylmercury alters the hormone levels of American white ibis, affecting their mating and nesting behavior and leading to lower reproduction rates; the American white ibis was one of the many bird species described by Carl Linnaeus in the 1758 10th edition of his Systema Naturae, where it was given the binomial name of Scolopax albus.
The species name is the Latin adjective albus "white". Alternative common names that have been used include white curlew. English naturalist Mark Catesby mistook immature birds for a separate species, which he called the brown curlew. Local creole names in Louisiana include bec petit flaman. Johann Georg Wagler gave the species its current binomial name in 1832 when he erected the new genus Eudocimus, whose only other species is the scarlet ibis. There has long been debate on whether the two should be considered subspecies or related species, the American Ornithologists' Union considers the two to be a superspecies as they are parapatric; the lack of observed hybrids was a large factor in the view. However, in a field study published in 1987, researchers Cristina Ramo and Benjamin Busto found evidence of interbreeding in a population where the ranges of the scarlet and white ibises overlap along the coast and in the Llanos region of Colombia and Venezuela, they observed individuals of the two species mating and pairing, as well as hybrid ibises with pale orange plumage, or white plumage with occasional orange feathers.
Hybrid ibises have been recorded in Florida, where the scarlet ibis has been introduced into wild populations of American white ibis. Birds of intermediate to red plumage have persisted for generations. Ornithologists James Hancock and Jim Kushlan consider the two to be a single species, with the differences in plumage, skin coloration and degree of bill darkening during breeding season forming the diagnostic characters, they have proposed the populations recontacted in northwestern South America after a period of separation, that the color difference is due to the presence of an enzyme that allows uptake of pigment in the diet. They have questioned whether white-plumaged birds of South America are in fact part of the ruber rather than the albus taxon, acknowledge that more investigation is needed to determine this; the white plumage and pink facial skin of adult American white ibises are distinctive. Adults have black wingtips that are only visible in flight. In non-breeding condition the long downcurved bill and long legs are bright red-orange.
During the first ten days of the breeding season, the skin darkens to a deep pink on the bill and an purple-tinted red on the legs. It fades to a paler pink, the tip of the bill becomes blackish, it is difficult to determine the sex of an adult American white ibis from its external appearance, since the sexes have similar plumage. However, there is sexual dimorphism in size and proportion as males are larger and heavier than females and have longer and stouter bills. A study of the American white ibis in southern Florida yielded weight ranges of 872.9 to 1,261 g for males and 592.7 to 861.3 g for females, with average weights of 1,036.4 g for males and 764.5 g for females. The length of adult female and male birds ranges from 53 to 70 cm with a 90 to 105 cm wingspan. Among standard measurements, American white ibis measure 20.5–31 cm along each wing, have a tail measurement of 9.3–12.2 cm, a tarsus of 6.75–11.3 cm and a culmen of 11–16.9 cm. The newly hatched American white ibis is covered with violet down feathers, deepening to dark brown or black on the head and wings.
The chest is bare and there can be a white tuft on the head. The irises are brown; the exposed skin is pi
Taxodium distichum is a deciduous conifer in the family Cupressaceae. It is native to the southeastern United States. Hardy and tough, this tree adapts to swampy, it is noted for the russet-red fall color of its lacy needles. This plant has some cultivated varieties and is used in groupings in public spaces. Common names include bald cypress, swamp cypress, white cypress, tidewater red cypress, gulf cypress and red cypress. Taxodium distichum is a large, slow-growing, long-lived tree, it grows to heights of 35–120 feet and has a trunk diameter of 3–6 feet. The main trunk is surrounded by cypress knees; the bark is grayish brown to reddish brown and fibrous with a stringy texture. The needle-like leaves are 1⁄2 to 3⁄4 inch long and are simple, alternate and linear, with entire margins. In autumn, the leaves turn yellow or copper red; the bald cypress drops its needles each winter and grows a new set in spring. This species is monoecious, with male and female flowers on a single plant forming on slender, tassel-like structures near the edge of branchlets.
The tree flowers in April and the seeds ripen in October. The male and female strobili are produced from buds formed in late autumn, with pollination in early winter, mature in about 12 months. Male cones emerge on panicles. Female cones are round and green while young, they turn hard and brown as the tree matures. They are 2.0 -- 3.5 cm in diameter. They have from 20 to 30 spirally arranged, four-sided scales, each bearing one, two, or three triangular seeds; each cone contains 20 to 40 large seeds. The cones disintegrate at maturity to release the seeds; the seeds are 5–10 mm long, the largest of any species of Cupressaceae, are produced every year, with heavy crops every 3–5 years. The seedlings have three to nine, but six, cotyledons each; the bald cypress grows in full sunlight to partial shade. This species can tolerate dry soil, it is moderately able to grow in aerosols of salt water. The cones are consumed by wildlife; this tree is suitable for cultivation in light and heavy soils. It does well in acid and alkaline soils and can grow in alkaline and saline soils.
It can grow in no shade. It can grow in water, it can tolerate atmospheric pollution. The tallest known specimen, near Williamsburg, Virginia, is 44.11 m tall, the stoutest known, in the Real County near Leaky, has a diameter at breast height of 475 in. The oldest known living specimen, in Bladen County, North Carolina, is over 1,620 years old, rendering it one of the oldest living plants in North America. Although there are specimens estimated to be nearly 2,000 years old at Sky Lake in Humphreys County, Mississippi determining their age is difficult because older trees become hollow; the related Taxodium ascendens is treated by some botanists as a distinct species, while others classify it as a variety of bald cypress, as Taxodium distichum var. imbricatum Croom. It differs in shorter leaves borne on erect shoots, in ecology, being confined to low-nutrient blackwater habitats. A few authors treat Taxodium mucronatum as a variety of bald cypress, as T. distichum var. mexicanum Gordon, thereby considering the genus as comprising only one species.
The native range extends from southeastern New Jersey south to Florida and west to East Texas and southeastern Oklahoma, inland up the Mississippi River. Ancient bald cypress forests, with some trees more than 1,700 years old, once dominated swamps in the Southeast; the range had been believed to extended north only as far as Delaware, but researchers have now found a natural forest on the Cape May Peninsula in southern New Jersey. The species can be found growing outside its natural native range; the largest remaining old-growth stands are at Corkscrew Swamp Sanctuary, near Naples, in the Three Sisters tract along eastern North Carolina's Black River. The Corkscrew trees are around 500 years of age, some exceed 40 m in height; the Black River trees were cored by dendrochronologist David Stahle from the University of Arkansas. He found that some began growing as early as 364 AD; this species is native to humid climates where annual precipitation ranges from about 760 mm or 30 inches in Texas to 1,630 mm or 64 inches along the Gulf Coast.
Although it grows best in warm climates, the natural northern limit of the species is not due to a lack of cold tolerance, but to specific reproductive requirements: further north, regeneration is prevented by ice damage to seedlings. Larger trees are able to tolerate lower humidity. In 2012 scuba divers discovered an underwater cypress forest several miles off the coast of Mobile, Alabama, in 60 feet of water; the forest contains trees that could not be dated with radiocarbon methods, indicating that they are more than 50,000 years old and thus most lived in the early glacial interval of the last ice age. The cypress forest is well preserved, when samples are cut they still smell like fresh cypress. A team, which has not yet published its results in a peer-reviewed journal, is studying the site. One possibility is that hurricane Katrina exposed the grove of bald cypress, protected under ocean floor sediments; the bald cypress is monoecious. Male and female strobili mature in one growing season from buds formed t
Black-crowned night heron
The black-crowned night heron, or black-capped night heron shortened to just night heron in Eurasia, is a medium-sized heron found throughout a large part of the world, except in the coldest regions and Australasia. Adults are 64 cm long and weigh 800 g, they have a black crown and back with the remainder of the body white or grey, red eyes, short yellow legs. They white under parts. Two or three long white plumes, erected in greeting and courtship displays, extend from the back of the head; the sexes are similar in appearance although the males are larger. Black-crowned night herons do not fit the typical body form of the heron family, they are stocky with shorter bills and necks than their more familiar cousins, the egrets and "day" herons. Their resting posture is somewhat hunched but when hunting they extend their necks and look more like other wading birds. Immature birds have dull grey-brown plumage on their heads and backs, with numerous pale spots, their underparts streaked with brown. The young birds have orange eyes and duller yellowish-green legs.
They are noisy birds in their nesting colonies, with calls that are transcribed as quok or woc. The breeding habitat is salt-water wetlands throughout much of the world; the subspecies N. n. hoactli breeds in North and South America from Canada as far south as northern Argentina and Chile, N. n. obscurus in southernmost South America, N. n. falklandicus in the Falkland Islands, the nominate race N. n. nycticorax in Europe and Africa. Black-crowned night herons nest in colonies on platforms of sticks in a group of trees, or on the ground in protected locations such as islands or reedbeds. Three to eight eggs are laid; this heron is otherwise resident. The North American population winters in Mexico, the southern United States, Central America, the West Indies, the Old World birds winter in tropical Africa and southern Asia. A colony of the herons has summered at the National Zoo in Washington, D. C. for more than a century. There are two archaeological specimens of the black-crowned night heron in Great Britain.
The oldest is from the Roman London Wall and the more recent from the Royal Navy's late medieval victualling yards in Greenwich It appears in the London poulterers price lists as the Brewe, a bird, thought to have been the Whimbrel or Glossy Ibis, which has now been shown to refer to the black-crowned night heron, derived from the medieval French Bihoreau. Black-crowned night heron may have bred in the wider landscape of pre-modern Britain, they were imported for the table so the bone specimens themselves do not prove they were part of the British avifauna. In modern times the Black-crowned Night Heron is a vagrant and feral breeding colonies were established at Edinburgh Zoo from 1950 into the 21st Century and at Great Witchingham in Norfolk where there were 8 pairs in 2003 but breeding was not repeated in 2004 or 2005. A pair of adults were seen with two fledged juveniles in Somerset in 2017, the first proven breeding record of wild black-crowned night herons in Great Britain; these birds stand still at the water's edge and wait to ambush prey at night or early morning.
They eat small fish, frogs, aquatic insects, small mammals, small birds. They are among the seven heron species observed to engage in bait fishing. During the day they rest in bushes. N. n. hoactli is more gregarious outside the breeding season than the nominate race. A thorough study performed by J. Sitko and P. Heneberg in the Czech Republic in 1962–2013 suggested that the central European black-crowned night herons host 8 helminth species; the dominant species consisted of Neogryporhynchus cheilancristrotus, Contracaecum microcephalum and Opistorchis longissimus. The mean number of helminth species recorded per host individual reached 1.41. In Ukraine, other helminth species are found in black-crowned night herons too, namely Echinochasmus beleocephalus, Echinochasmus ruficapensis, Clinostomum complanatum and Posthodiplostomum cuticola. Nycticorax means "night raven" and derives from the Ancient Greek nuktos "night" and korax, "raven", it refers to the nocturnal feeding habits and croaking crow-like call of this species.
In the Falkland Islands, the bird is called "quark", an onomatopoeia similar to its name in many other languages, like "qua-bird" in English, "kwak" in Dutch and West Frisian, "kvakoš noční" in Czech, "квак" in Ukrainian, "кваква" in Russian, "vạc" in Vietnamese, "kowak-malam" in Indonesian, "waqwa" in Quechua. Black-crowned night heron on F. Gary. A Guide to the Birds of Costa Rica. Cornell University Press. ISBN 978-0-8014-9600-4. Hancock, James. Herons and Egrets of the World. Academic Press. ISBN 978-0-12-322725-6. Sibley, David; the Sibley Guide to Birds. Knopf. ISBN 978-0-679-45122-8. Blasco-Zumeta, Javier. "Black-crowned night heron". Identification Atlas of Aragon's Birds. Black-crowned Night-Heron Species Account – Cornell Lab of Ornithology Black-crowned night-heron - Nycticorax nycticorax - USGS Patuxent Bird Identification InfoCenter Blackcrowned Night Heron - The Atlas of Southern African Birds Black-crowned
Duckweeds, or water lenses, are flowering aquatic plants which float on or just beneath the surface of still or slow-moving bodies of fresh water and wetlands. Known as "bayroot", they arose from within the arum or aroid family, so are classified as the subfamily Lemnoideae within the Araceae. Other classifications those created prior to the end of the 20th century, place them as a separate family, Lemnaceae; these plants leaves. The greater part of each plant is a small organized "thallus" or "frond" structure only a few cells thick with air pockets that allow it to float on or just under the water surface. Depending on the species, each plant may have one or more simple rootlets. Reproduction is by asexual budding, which occurs from a meristem enclosed at the base of the frond. Three tiny "flowers" consisting of two stamens and a pistil are produced, by which sexual reproduction occurs; some view this "flower" as a pseudanthium, or reduced inflorescence, with three flowers that are distinctly either female or male and which are derived from the spadix in the Araceae.
Evolution of the duckweed inflorescence remains ambiguous due to the considerable evolutionary reduction of these plants from their earlier relatives. The flower of the duckweed genus Wolffia is the smallest known, measuring 0.3 mm long. The fruit produced through this occasional reproduction is a utricle, a seed is produced in a bag containing air that facilitates flotation. One of the more important factors influencing the distribution of wetland plants, aquatic plants in particular, is nutrient availability. Duckweeds tend to be associated with fertile eutrophic conditions, they can be spread by waterfowl and small mammals, transported inadvertently on their feet and bodies, as well as by moving water. In water bodies with constant currents or overflow, the plants are carried down the water channels and do not proliferate greatly. In some locations, a cyclical pattern driven by weather patterns exists in which the plants proliferate during low water-flow periods are carried away as rainy periods ensue.
Duckweed is an important high-protein food source for waterfowl. The tiny plants provide cover for fry of many aquatic species; the plants are used as shelter by pond-water species such as bullfrogs and fish such as bluegills. They provide shade and, although confused with them, can reduce certain light-generated growths of photoautotrophic algae. Duckweed is eaten by humans in some parts of Southeast Asia; as it contains more protein than soybeans, it is sometimes cited as a significant potential food source. Some initial investigations to what extent duckweed could be introduced in European markets show little consumer objection to the idea; the plants can provide nitrate removal, if cropped, the duckweeds are important in the process of bioremediation because they grow absorbing excess mineral nutrients nitrogen and phosphates. For these reasons, they are touted as water purifiers of untapped value; the Swiss Department of Water and Sanitation in Developing Countries, associated with the Swiss Federal Institute for Environmental Science and Technology, asserts that as well as the food and agricultural values, duckweed may be used for wastewater treatment to capture toxins and for odor control, that if a mat of duckweed is maintained during harvesting for removal of the toxins captured thereby, it prevents the development of algae and controls the breeding of mosquitoes.
The same publication provides an extensive list of references for many duckweed-related topics. These plants may play a role in conservation of water because a cover of duckweed will reduce evaporation of water when compared to the rate of a sized water body with a clear surface. Despite some of these benefits, because duckweed thrives in high-nutrient wetland environments, they can be seen as a nuisance species when conditions allow them to excessively proliferate in environments that are traditionally low in nutrients; this is the case within the Everglades, where surface runoff and agricultural pollution have introduced increased levels of nutrients into an otherwise low-nutrient wetland system, which allows fast growing species such as duckweed to establish themselves and displace other native species such as sawgrass. The duckweeds have long been a taxonomic mystery, have been considered to be their own family, the Lemnaceae, they reproduce asexually. Flowers, if present at all, are small.
Roots are either much reduced, or absent entirely. They were suspected of being related to the Araceae as long ago as 1876, but until the advent of molecular phylogeny, testing this hypothesis was difficult. Starting in 1995, studies began to confirm their placement in the Araceae and since most systematists consider them to be part of that family, their position within their family has been less clear, but several 21st-century studies place them in the position shown below. They are not related to Pistia, an aquatic plant in the family Araceae; the genera of duckweeds are: Spirodela, Lemna and Wolffia. Duckweed genome sizes have a 10-fold range representing diploids to octaploids; the ancestral genus of Spirodela has the smallest genome size, while the most derived genus, contains plants with the largest genome size. DNA sequencing has shown that Wolffiella and Wolffia are more related than the others. Spirodela is at the basal position of the taxon, followed by Lemna, Wo
The common gallinule is a bird in the family Rallidae. It was split from the common moorhen by the American Ornithologists' Union in July 2011, it lives around well-vegetated marshes, ponds and other wetlands in the Americas. The species is not found in many tropical rainforests. Elsewhere, the common gallinule is the most seen rail species in much of North America, excepting the American coot in some regions; the gallinule has dark plumage apart from yellow legs and a red frontal shield. The young lack the red shield, it will emit loud hisses when threatened. This is a common breeding bird in well-vegetated lakes. Populations in areas where the waters freeze, such as southern Canada and the northern USA, will migrate to more temperate climes; this species will consume a wide variety of small aquatic creatures. It forages in the water, sometimes upending in the water to feed, its wide feet allow it to hop about on lily pads. It is secretive, but can become tame in some areas. Despite loss of habitat in parts of its range, the common gallinule remains plentiful and widespread.
The common gallinule will fight to defend its territory. The nest is a basket built on the ground in dense vegetation. Laying starts between mid-March and mid-May in northern hemisphere temperate regions. About 8 eggs are laid per female early in the season. Nests may be re-used by different females. Incubation lasts about three weeks. Both parents feed the young; these fledge after 40–50 days, become independent a few weeks thereafter, may raise their first brood the next spring. When threatened, the young may cling to a parent's body, after which the adult birds fly away to safety, carrying their offspring with them; this species is parasitized by the moorhen flea, Dasypsyllus gallinulae. Seven subspecies are today considered valid. Most are not readily recognizable, as differences are rather subtle and clinal; the location of a sighting is the most reliable indication as to subspecies identification, but the migratory tendencies of this species make identifications based on location not reliable.
In addition to the extant subspecies listed below, there is a Pleistocene population known from fossils: the larger and long-winged paleosubspecies G. g. brodkorbi is known from the Ichetucknee River deposits in Florida. It was described as a distinct species, but is the direct ancestor of some of today's common gallinules; the presence in the same deposits of fossils typical of the shorter-winged and more delicate G. g. cerceris suggests that G. g. brodkorbi was not ancestral to the Antillean gallinule of our time but rather to the more northerly North American subspecies. Dronen, Norman O.. S. A.. Zootaxa 1131: 49–58. PDF fulltext Olson, Storrs L.: The Pleistocene Rails of North America. Condor 76: 169–175. DjVu fulltext PDF fulltext Common Gallinule Species Account – Cornell Lab of Ornithology Common Moorhen - Gallinula chloropus - USGS Patuxent Bird Identification InfoCenter