Friday, November 26, 2010

WATER POLLUTION






Water pollution is the contamination of water bodies (e.g. lakes, rivers, oceans and groundwater).

Water pollution affects plants and organisms living in these bodies of water; and, in almost all cases the effect is damaging not only to individual species and populations, but also to the natural biological communities.

Water pollution occurs when pollutants are discharged directly or indirectly into water bodies without adequate treatment to remove harmful compounds.
Contents

* 1 Introduction
* 2 Water pollution categories
o 2.1 Point source pollution
o 2.2 Non–point source pollution
* 3 Groundwater pollution
* 4 Causes of water pollution
o 4.1 Pathogens
o 4.2 Chemical and other contaminants
o 4.3 Thermal pollution
* 5 Transport and chemical reactions of water pollutants
* 6 Measurement of water pollution
o 6.1 Sampling
o 6.2 Physical testing
o 6.3 Chemical testing
o 6.4 Biological testing
* 7 Control of water pollution
o 7.1 Domestic sewage
o 7.2 Industrial wastewater
o 7.3 Agricultural wastewater
o 7.4 Construction site stormwater
o 7.5 Urban runoff (stormwater)

Introduction
Millions depend on the polluted Ganges river.

Water pollution is a major problem in the global context. It has been suggested that it is the leading worldwide cause of deaths and diseases,and that it accounts for the deaths of more than 14,000 people daily.An estimated 700 million Indians have no access to a proper toilet, and 1,000 Indian children die of diarrheal sickness every day.Some 90% of China's cities suffer from some degree of water pollution,and nearly 500 million people lack access to safe drinking water.In addition to the acute problems of water pollution in developing countries, industrialized countries continue to struggle with pollution problems as well. In the most recent national report on water quality in the United States, 45 percent of assessed stream miles, 47 percent of assessed lake acres, and 32 percent of assessed bay and estuarine square miles were classified as polluted.

Water is typically referred to as polluted when it is impaired by anthropogenic contaminants and either does not support a human use, like serving as drinking water, and/or undergoes a marked shift in its ability to support its constituent biotic communities, such as fish. Natural phenomena such as volcanoes, algae blooms, storms, and earthquakes also cause major changes in water quality and the ecological status of water.
Water pollution categories

Surface water and groundwater have often been studied and managed as separate resources, although they are interrelated.Sources of surface water pollution are generally grouped into two categories based on their origin.
Point source pollution
Point source pollution - Shipyard - Rio de Janeiro.

Point source pollution refers to contaminants that enter a waterway through a discrete conveyance, such as a pipe or ditch. Examples of sources in this category include discharges from a sewage treatment plant, a factory, or a city storm drain. The U.S. Clean Water Act (CWA) defines point source for regulatory enforcement purposes.The CWA definition of point source was amended in 1987 to include municipal storm sewer systems, as well as industrial stormwater, such as from construction sites.
Non–point source pollution

Non–point source (NPS) pollution refers to diffuse contamination that does not originate from a single discrete source. NPS pollution is often the cumulative effect of small amounts of contaminants gathered from a large area. The leaching out of nitrogen compounds from agricultural land which has been fertilized is a typical example. Nutrient runoff in stormwater from "sheet flow" over an agricultural field or a forest are also cited as examples of NPS pollution.

Contaminated storm water washed off of parking lots, roads and highways, called urban runoff, is sometimes included under the category of NPS pollution. However, this runoff is typically channeled into storm drain systems and discharged through pipes to local surface waters, and is a point source. However where such water is not channeled and drains directly to ground it is a non-point source.
Groundwater pollution
See also: Hydrogeology

Interactions between groundwater and surface water are complex. Consequently, groundwater pollution, sometimes referred to as groundwater contamination, is not as easily classified as surface water pollution. By its very nature, groundwater aquifers are susceptible to contamination from sources that may not directly affect surface water bodies, and the distinction of point vs. non-point source may be irrelevant. A spill or ongoing releases of chemical or radionuclide contaminants into soil (located away from a surface water body) may not create point source or non-point source pollution, but can contaminate the aquifer below, defined as a toxin plume. The movement of the plume, a plume front, can be part of a Hydrological transport model or Groundwater model. Analysis of groundwater contamination may focus on the soil characteristics and site geology, hydrogeology, hydrology, and the nature of the contaminants.
Causes of water pollution

The specific contaminants leading to pollution in water include a wide spectrum of chemicals, pathogens, and physical or sensory changes such as elevated temperature and discoloration. While many of the chemicals and substances that are regulated may be naturally occurring (calcium, sodium, iron, manganese, etc.) the concentration is often the key in determining what is a natural component of water, and what is a contaminant.

Oxygen-depleting substances may be natural materials, such as plant matter (e.g. leaves and grass) as well as man-made chemicals. Other natural and anthropogenic substances may cause turbidity (cloudiness) which blocks light and disrupts plant growth, and clogs the gills of some fish species.

Many of the chemical substances are toxic. Pathogens can produce waterborne diseases in either human or animal hosts. Alteration of water's physical chemistry includes acidity (change in pH), electrical conductivity, temperature, and eutrophication. Eutrophication is an increase in the concentration of chemical nutrients in an ecosystem to an extent that increases in the primary productivity of the ecosystem. Depending on the degree of eutrophication, subsequent negative environmental effects such as anoxia (oxygen depletion) and severe reductions in water quality may occur, affecting fish and other animal populations.
[edit] Pathogens
A manhole cover unable to contain a sanitary sewer overflow.

Coliform bacteria are a commonly used bacterial indicator of water pollution, although not an actual cause of disease. Other microorganisms sometimes found in surface waters which have caused human health problems include:

* Burkholderia pseudomallei
* Cryptosporidium parvum
* Giardia lamblia
* Salmonella
* Novovirus and other viruses
* Parasitic worms (helminths).

High levels of pathogens may result from inadequately treated sewage discharges.This can be caused by a sewage plant designed with less than secondary treatment (more typical in less-developed countries). In developed countries, older cities with aging infrastructure may have leaky sewage collection systems (pipes, pumps, valves), which can cause sanitary sewer overflows. Some cities also have combined sewers, which may discharge untreated sewage during rain storms.

Pathogen discharges may also be caused by poorly managed livestock operations.
Chemical and other contaminants
Muddy river polluted by sediment. Photo courtesy of United States Geological Survey.

Contaminants may include organic and inorganic substances.

Organic water pollutants include:

* Detergents
* Disinfection by-products found in chemically disinfected drinking water, such as chloroform
* Food processing waste, which can include oxygen-demanding substances, fats and grease
* Insecticides and herbicides, a huge range of organohalides and other chemical compounds
* Petroleum hydrocarbons, including fuels (gasoline, diesel fuel, jet fuels, and fuel oil) and lubricants (motor oil), and fuel combustion byproducts, from stormwater runoff
* Tree and bush debris from logging operations
* Volatile organic compounds (VOCs), such as industrial solvents, from improper storage. Chlorinated solvents, which are dense non-aqueous phase liquids (DNAPLs), may fall to the bottom of reservoirs, since they don't mix well with water and are denser.
* Various chemical compounds found in personal hygiene and cosmetic products

Inorganic water pollutants include:

* Acidity caused by industrial discharges (especially sulfur dioxide from power plants)
* Ammonia from food processing waste
* Chemical waste as industrial by-products
* Fertilizers containing nutrients--nitrates and phosphates--which are found in stormwater runoff from agriculture, as well as commercial and residential use
* Heavy metals from motor vehicles (via urban stormwater runoff) and acid mine drainage
* Silt (sediment) in runoff from construction sites, logging, slash and burn practices or land clearing sites

Macroscopic pollution—large visible items polluting the water—may be termed "floatables" in an urban stormwater context, or marine debris when found on the open seas, and can include such items as:

* Trash (e.g. paper, plastic, or food waste) discarded by people on the ground, and that are washed by rainfall into storm drains and eventually discharged into surface waters
* Nurdles, small ubiquitous waterborne plastic pellets
* Shipwrecks, large derelict ships

Potrero Generating Station discharges heated water into San Francisco Bay.
Thermal pollution
Main article: Thermal pollution

Thermal pollution is the rise or fall in the temperature of a natural body of water caused by human influence. A common cause of thermal pollution is the use of water as a coolant by power plants and industrial manufacturers. Elevated water temperatures decreases oxygen levels (which can kill fish) and affects ecosystem composition, such as invasion by new thermophilic species. Urban runoff may also elevate temperature in surface waters.

Thermal pollution can also be caused by the release of very cold water from the base of reservoirs into warmer rivers.
Transport and chemical reactions of water pollutants
See also: Marine pollution

Most water pollutants are eventually carried by rivers into the oceans. In some areas of the world the influence can be traced hundred miles from the mouth by studies using hydrology transport models. Advanced computer models such as SWMM or the DSSAM Model have been used in many locations worldwide to examine the fate of pollutants in aquatic systems. Indicator filter feeding species such as copepods have also been used to study pollutant fates in the New York Bight, for example. The highest toxin loads are not directly at the mouth of the Hudson River, but 100 kilometers south, since several days are required for incorporation into planktonic tissue. The Hudson discharge flows south along the coast due to coriolis force. Further south then are areas of oxygen depletion, caused by chemicals using up oxygen and by algae blooms, caused by excess nutrients from algal cell death and decomposition. Fish and shellfish kills have been reported, because toxins climb the food chain after small fish consume copepods, then large fish eat smaller fish, etc. Each successive step up the food chain causes a stepwise concentration of pollutants such as heavy metals (e.g. mercury) and persistent organic pollutants such as DDT. This is known as biomagnification, which is occasionally used interchangeably with bioaccumulation.
A polluted river draining an abandoned copper mine on Anglesey

Large gyres (vortexes) in the oceans trap floating plastic debris. The North Pacific Gyre for example has collected the so-called "Great Pacific Garbage Patch" that is now estimated at 100 times the size of Texas. Many of these long-lasting pieces wind up in the stomachs of marine birds and animals. This results in obstruction of digestive pathways which leads to reduced appetite or even starvation.

Many chemicals undergo reactive decay or chemically change especially over long periods of time in groundwater reservoirs. A noteworthy class of such chemicals is the chlorinated hydrocarbons such as trichloroethylene (used in industrial metal degreasing and electronics manufacturing) and tetrachloroethylene used in the dry cleaning industry (note latest advances in liquid carbon dioxide in dry cleaning that avoids all use of chemicals). Both of these chemicals, which are carcinogens themselves, undergo partial decomposition reactions, leading to new hazardous chemicals (including dichloroethylene and vinyl chloride).

Groundwater pollution is much more difficult to abate than surface pollution because groundwater can move great distances through unseen aquifers. Non-porous aquifers such as clays partially purify water of bacteria by simple filtration (adsorption and absorption), dilution, and, in some cases, chemical reactions and biological activity: however, in some cases, the pollutants merely transform to soil contaminants. Groundwater that moves through cracks and caverns is not filtered and can be transported as easily as surface water. In fact, this can be aggravated by the human tendency to use natural sinkholes as dumps in areas of Karst topography.

There are a variety of secondary effects stemming not from the original pollutant, but a derivative condition. An example is silt-bearing surface runoff, which can inhibit the penetration of sunlight through the water column, hampering photosynthesis in aquatic plants.
Measurement of water pollution
Environmental Scientists preparing water autosamplers.

Water pollution may be analyzed through several broad categories of methods: physical, chemical and biological. Most involve collection of samples, followed by specialized analytical tests. Some methods may be conducted in situ, without sampling, such as temperature. Government agencies and research organizations have published standardized, validated analytical test methods to facilitate the comparability of results from disparate testing events.
Sampling

Sampling of water for physical or chemical testing can be done by several methods, depending on the accuracy needed and the characteristics of the contaminant. Many contamination events are sharply restricted in time, most commonly in association with rain events. For this reason "grab" samples are often inadequate for fully quantifying contaminant levels. Scientists gathering this type of data often employ auto-sampler devices that pump increments of water at either time or discharge intervals.

Sampling for biological testing involves collection of plants and/or animals from the surface water body. Depending on the type of assessment, the organisms may be identified for biosurveys (population counts) and returned to the water body, or they may be dissected for bioassays to determine toxicity.
Physical testing

Common physical tests of water include temperature, solids concentration like total suspended solids (TSS) and turbidity.
Chemical testing
See also: water chemistry analysis and environmental chemistry

Water samples may be examined using the principles of analytical chemistry. Many published test methods are available for both organic and inorganic compounds. Frequently used methods include pH, biochemical oxygen demand (BOD), chemical oxygen demand (COD), nutrients (nitrate and phosphorus compounds), metals (including copper, zinc, cadmium, lead and mercury), oil and grease, total petroleum hydrocarbons (TPH), and pesticides.
Biological testing
Main article: Bioindicator

Biological testing involves the use of plant, animal, and/or microbial indicators to monitor the health of an aquatic ecosystem.

For microbial testing of drinking water, see Bacteriological water analysis.

Control of water pollution
Domestic sewage
Main article: Sewage treatment
Deer Island Waste Water Treatment Plant serving Boston, Massachusetts and vicinity.

Domestic sewage is 99.9% pure water, the other 0.1% are pollutants. While found in low concentrations, these pollutants pose risk on a large scale.In urban areas, domestic sewage is typically treated by centralized sewage treatment plants. In the U.S., most of these plants are operated by local government agencies, frequently referred to as publicly owned treatment works (POTW). Municipal treatment plants are designed to control conventional pollutants: BOD and suspended solids. Well-designed and operated systems (i.e., secondary treatment or better) can remove 90 percent or more of these pollutants. Some plants have additional sub-systems to treat nutrients and pathogens. Most municipal plants are not designed to treat toxic pollutants found in industrial wastewater.

Cities with sanitary sewer overflows or combined sewer overflows employ one or more engineering approaches to reduce discharges of untreated sewage, including:

* utilizing a green infrastructure approach to improve stormwater management capacity throughout the system, and reduce the hydraulic overloading of the treatment plant
* repair and replacement of leaking and malfunctioning equipment
* increasing overall hydraulic capacity of the sewage collection system (often a very expensive option).

A household or business not served by a municipal treatment plant may have an individual septic tank, which treats the wastewater on site and discharges into the soil. Alternatively, domestic wastewater may be sent to a nearby privately owned treatment system (e.g. in a rural community).
Industrial wastewater
Main article: Industrial wastewater treatment
Dissolved air flotation system for treating industrial wastewater.

Some industrial facilities generate ordinary domestic sewage that can be treated by municipal facilities. Industries that generate wastewater with high concentrations of conventional pollutants (e.g. oil and grease), toxic pollutants (e.g. heavy metals, volatile organic compounds) or other nonconventional pollutants such as ammonia, need specialized treatment systems. Some of these facilities can install a pre-treatment system to remove the toxic components, and then send the partially treated wastewater to the municipal system. Industries generating large volumes of wastewater typically operate their own complete on-site treatment systems.

Some industries have been successful at redesigning their manufacturing processes to reduce or eliminate pollutants, through a process called pollution prevention.

Heated water generated by power plants or manufacturing plants may be controlled with:

* cooling ponds, man-made bodies of water designed for cooling by evaporation, convection, and radiation
* cooling towers, which transfer waste heat to the atmosphere through evaporation and/or heat transfer
* cogeneration, a process where waste heat is recycled for domestic and/or industrial heating purposes.

Agricultural wastewater
Main article: Agricultural wastewater treatment
Riparian buffer lining a creek in Iowa

Nonpoint source controls
Sediment (loose soil) washed off fields is the largest source of agricultural pollution in the United States.Farmers may utilize erosion controls to reduce runoff flows and retain soil on their fields. Common techniques include contour plowing, crop mulching, crop rotation, planting perennial crops and installing riparian buffers.

Nutrients (nitrogen and phosphorus) are typically applied to farmland as commercial fertilizer; animal manure; or spraying of municipal or industrial wastewater (effluent) or sludge. Nutrients may also enter runoff from crop residues, irrigation water, wildlife, and atmospheric deposition.Farmers can develop and implement nutrient management plans to reduce excess application of nutrients.

To minimize pesticide impacts, farmers may use Integrated Pest Management (IPM) techniques (which can include biological pest control) to maintain control over pests, reduce reliance on chemical pesticides, and protect water quality.
Confined Animal Feeding Operation in the United States

Point source wastewater treatment
Farms with large livestock and poultry operations, such as factory farms, are called concentrated animal feeding operations or confined animal feeding operations in the U.S. and are being subject to increasing government regulation.Animal slurries are usually treated by containment in lagoons before disposal by spray or trickle application to grassland. Constructed wetlands are sometimes used to facilitate treatment of animal wastes, as are anaerobic lagoons. Some animal slurries are treated by mixing with straw and composted at high temperature to produce a bacteriologically sterile and friable manure for soil improvement.
Construction site stormwater
Silt fence installed on a construction site.

Sediment from construction sites is managed by installation of:

* erosion controls, such as mulching and hydroseeding, and
* sediment controls, such as sediment basins and silt fences.

Discharge of toxic chemicals such as motor fuels and concrete washout is prevented by use of:

* spill prevention and control plans, and
* specially designed containers (e.g. for concrete washout) and structures such as overflow controls and diversion berms.

Urban runoff (stormwater)
Main article: Urban runoff
Retention basin for controlling urban runoff

Effective control of urban runoff involves reducing the velocity and flow of stormwater, as well as reducing pollutant discharges. Local governments use a variety of stormwater management techniques to reduce the effects of urban runoff. These techniques, called best management practices (BMPs) in the U.S., may focus on water quantity control, while others focus on improving water quality, and some perform both functions.

Pollution prevention practices include low impact development techniques, installation of green roofs and improved chemical handling (e.g. management of motor fuels & oil, fertilizers and pesticides).Runoff mitigation systems include infiltration basins, bioretention systems, constructed wetlands, retention basins and similar devices.

Thermal pollution from runoff can be controlled by stormwater management facilities that absorb the runoff or direct it into groundwater, such as bioretention systems and infiltration basins. Retention basins tend to be less effective at reducing temperature, as the water may be heated by the sun before being discharged to a receiving stream

CASSOWARY VERY DANGER BIRD






For other uses, see Cassowary (disambiguation).
Cassowary
Fossil range: Pliocene to present
Southern Cassowary at Jurong Bird Park, Singapore
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Casuariiformes
Family: Casuariidae
Genus: Casuarius
Brisson, 1760
Species

Casuarius casuarius
Southern Cassowary
Casuarius unappendiculatus
Northern Cassowary
Casuarius bennetti
Dwarf Cassowary
†Casuarius lydekki

The cassowary (genus Casuarius) is a very large flightless bird native to the tropical forests of New Guinea, nearby islands and northeastern Australia.[2]

The Southern Cassowary is the third tallest and second heaviest living bird, smaller only than the ostrich and emu.

Cassowaries feed mainly on fruits, though all species are truly omnivorous and will take a range of other plant food including shoots, grass seeds, and fungi in addition to invertebrates and small vertebrates.

Cassowaries are very shy, but when disturbed, they are capable of inflicting serious injuries to dogs and children.
Contents


* 1 Taxonomy and evolution
* 2 Description
* 3 Behaviour
o 3.1 Reproductive
o 3.2 Diet
* 4 Distribution and habitat
* 5 Threats
* 6 Cassowary attacks
* 7 Role in seed dispersal and germination

Taxonomy and evolution

Cassowaries (from the Malay name kesuari)are part of the ratite group, which also includes the Emu, rheas, ostriches, and kiwis, and the extinct moas and elephant birds. There are three extant species recognized today and one extinct:

* Casuarius casuarius, Southern Cassowary or Double-wattled Cassowary, found in southern New Guinea, northeastern Australia, and the Aru Islands,mainly in lowlands.
* Casuarius bennetti, Dwarf Cassowary or Bennett's Cassowary, found in New Guinea, New Britain, and on Yapen,mainly in highlands.
* Casuarius unappendiculatus, Northern Cassowary or Single-wattled Cassowary, found in the northern and western New Guinea, and Yapen,mainly in lowlands.
* Casuarius lydekki Extinct

Presently, most authorities consider the above monotypic, but several subspecies have been described of each (some have even been suggested as separate species, e.g., C. (b) papuanus).It has proven very difficult to confirm the validity of these due to individual variations, age-related variations, the relatively few available specimens (and the bright skin of the head and neck–the basis of which several subspecies have been described–fades in specimens), and that locals are known to have traded live cassowaries for hundreds, if not thousands, of years, some of which are likely to have escaped or deliberately introduced to regions away from their origin.
Illustration of cassowary skull

The evolutionary history of cassowaries, as of all ratites, is not well known. A fossil species was reported from Australia, but for reasons of biogeography this assignment is not certain and it might belong to the prehistoric "emuwaries", Emuarius, which were cassowary-like primitive emus.
Description

The Northern and Dwarf Cassowaries are not well known. All cassowaries are usually shy birds of the deep forest, adept at disappearing long before a human knows they are there. Even the more accessible Southern Cassowary of the far north Queensland rain forests is not well understood.

Females are bigger and more brightly coloured. Adult Southern Cassowaries are 1.5 to 1.8 metres (59–71 in) tall, although some females may reach 2 metres (79 in),[5] and weigh 58.5 kilograms (129 lb).

All cassowaries have feathers that consist of a shaft and loose barbules. They do not have retrices (tail feathers) or a preen gland. Cassowaries have small wings with 5-6 large remeges. These are reduced to stiff, keratinous quills, like porcupine quills, with no barbs.A claw is on each second finger.The furcula and coracoid are degenerate, and their palatal bones and sphenoid bones touch each other.These, along with their wedge-shaped body, are thought to be adaptations to ward off vines, thorns and saw-edged leaves, allowing them to run quickly through the rainforest.

A cassowary's three-toed feet have sharp claws. The second toe, the inner one in the medial position, sports a dagger-like claw that is 125 millimetres (5 in) long[6]. This claw is particularly fearsome since cassowaries sometimes kick humans and animals with their enormously powerful legs (see Cassowary Attacks, below). Cassowaries can run up to 50 km/h (31 mph) through the dense forest. They can jump up to 1.5 metres (4.9 ft)[citation needed]and they are good swimmers, crossing wide rivers and swimming in the sea as well.
Detail of a Southern Cassowary head.

All three species have horn-like but soft and spongy crests called casques on their heads, up to 18 cm (7 in).These consist of "a keratinous skin over a core of firm, cellular foam-like material".Several purposes for the casques have been proposed. One possibility is that they are secondary sexual characteristics. Other suggestions include that they are used to batter through underbrush, as a weapon for dominance disputes, or as a tool for pushing aside leaf litter during foraging. The latter three are disputed by biologist Andrew Mack, whose personal observation suggests that the casque amplifies deep sounds.However, the earlier article by Crome and Moore says that the birds do lower their heads when they are running "full tilt through the vegetation, brushing saplings aside and occasionally careening into small trees. The casque would help protect the skull from such collisions." Mack and Jones also speculate that the casques play a role in either sound reception or acoustic communication. This is related to their discovery that at least the Dwarf Cassowary and Southern Cassowary produce very-low frequency sounds, which may aid in communication in dense rainforest.This "boom" is the lowest known bird call, and is on the edge of human hearing.

The average lifespan of wild cassowaries is believed to be about 40 to 50 years.
Behaviour

Cassowaries are solitary birds except during courtship, egg-laying, and sometimes around ample food supplies.[8] Male cassowaries defend a territory of about 7 square kilometres (2.8 square miles) for itself and its mate, while females have overlapping territories of several males.
Southern Cassowary at Brevard Zoo, USA
Reproductive

The breeding season starts in May or June. Females lay three to eight large, dark bright green or pale green-blue eggs in each clutch into a prepared heap of leaf litter.These eggs measure about 9 by 14 centimetres (3.5 by 5.5 in) — only Ostrich and Emu eggs are larger. The female does not care for the eggs or the chicks but moves on to lay eggs in the nests of several other males. The male incubates the eggs for 50–52 days, removing or adding litter to regulate the temperature, then protects the brown-striped chicks who stay in the nest for about nine months, defending them fiercely against all potential predators, including humans. The young males then go off to find a territory of their own.

"Young cassowaries are brown and have buffy stripes. They are often kept as pets in native villages [in New Guinea], where they are permitted to roam like barnyard fowl. Often they are kept until they become nearly grown and someone gets hurt. Mature cassowaries are placed beside native houses in cribs hardly larger than the birds themselves. Garbage and other vegetable food is fed them, and they live for years in such enclosures; for in some areas their plumage is still as valuable as shell money. Caged birds are regularly bereft of their fresh plumes."

Diet

Cassowaries are predominantly frugivorous, but they will take flowers, fungi, snails, insects, frogs, birds, fish, rats, mice, and carrion. Fruit from at least twenty-six plant families have been documented in the diet of cassowaries. Fruits from the laurel, podocarp, palm, wild grape, nightshade, and myrtle families are important items in the diet.The cassowary plum takes its name from the bird.

Where trees are dropping fruit, cassowaries will come in and feed, with each bird defending a tree from others for a few days. They move on when the fruit is depleted. Fruit is swallowed whole, even items as large as bananas and apples.

Cassowaries are a keystone species of rain forests because they eat fallen fruit whole and distribute seeds across the jungle floor via excrement.

As for eating the Cassowary, it is supposed to be quite tough. Australian administrative officers stationed in New Guinea were advised that it "should be cooked with a stone in the pot: when the stone is ready to eat so is the Cassowary".
Distribution and habitat

Cassowaries are native to the humid rainforests of New Guinea and nearby smaller islands, and northeastern Australia.They will, however, venture out into palm scrub, grassland, savanna, and swamp forest.It is unclear if some islands' populations are natural or the result of trade in young birds by natives.
Threats
A road sign in Cairns, Queensland, Australia

The Southern Cassowary is endangered in Queensland, Australia. Kofron and Chapman (2006) assessed the decline of this species. They found that, of the former cassowary habitat, only 20 - 25% remains. They stated that habitat loss and fragmentation is the primary cause of decline.They then studied 140 cases of cassowary mortality and found that motor vehicle strikes accounted for 55% of them, and dog attacks produced another 18%. Remaining causes of death included hunting (5 cases), entanglement in wire (1 case), the removal of cassowaries that attacked humans (4 cases), and natural causes (18 cases), including tuberculosis (4 cases). 15 cases were for unknown reasons.

Hand feeding of cassowaries poses a big threat to their survival, because it lures them into suburban areas. There, the birds are more susceptible to vehicles and dogs.Contact with humans encourages Cassowaries to take food from picnic tables.

Feral pigs are a huge problem. They destroy nests and eggs but their worst effect is as competitors for food, which could be catastrophic for the Cassowaries during lean times.
Cassowary attacks

Cassowaries have a reputation for being dangerous to people and domestic animals. During World War II American and Australian troops stationed in New Guinea were warned to steer clear of them. Many internet entries about cassowaries state that they can disembowel a human or dog with one kick, with the long second toe claw cutting the gut open.

In his book "Living Birds of the World" from 1958, Ornithologist Thomas E. Gilliard wrote;

"The inner or second of the three toes is fitted with a long, straight, murderous nail which can sever an arm or eviscerate an abdomen with ease. There are many records of natives being killed by this bird."

However, Gilliard did not include any such records or any references for them, and although this assessment of the danger posed by cassowaries has been repeated in print by authors including Gregory S. Paul (1988)and Jared Diamond (1997), recent research on hundreds of cassowary attacks has only been able to find one human death. A 2003 study of attacks by the Southern Cassowary in Queensland found no wounds larger than punctures about 1.5 cm in diameter.Of 221 attacks studied, 150 were against humans. 75% of these were from cassowaries that had been fed by people. 71% of the time the bird chased or charged the victim. 15% of the time they kicked. Of the attacks, 73% involved the birds expecting or snatching food, 5% involved defending natural food sources, 15% involved defending themselves from attack, 7% involved defending their chicks or eggs. Of all 150 attacks there was only one human death.

The one documented human death caused by a cassowary was that of Phillip McClean, aged 16, and it happened on 6 April 1926. He and his brother, aged 13, were attempting to beat the cassowary to death with clubs. They were accompanied by their dog. The bird kicked the younger boy, who fell and ran away. Then the older boy struck the bird. The bird charged and knocked the older boy to the ground. While on the ground, Phillip was kicked in the neck, opening a 1.25 cm wound. Phillip got up and ran but died shortly afterwards from the hemorrhaging blood vessel in his neck.

Cassowary strikes to the abdomen are among the rarest of all, but there is one case of a dog that was kicked in the belly in 1995. The blow left no puncture, but there was severe bruising. The dog later died from an apparent intestinal rupture.
Role in seed dispersal and germination
Casuarius casuarius scat

Cassowaries feed on the fruits of several hundred rainforest species and usually pass viable seeds in large dense scats. They are known to disperse seeds over distances greater than a kilometre, and thus play an important role in the ecosystem. Germination rates for seeds of the rare Australian rainforest tree Ryparosa were found to be much higher after passing through a cassowary's gut (92% versus 4%).
In popular culture

In the video game series Ty the Tasmanian Tiger, the main antagonist of the series is a mammal-loathing cassowary named Boss Cass.

Cassowaries were in the animated film Ferngully: The Last Rainforest

ABOUT GREEN ANACONDA





















This article is about the snake. For other uses, see Anaconda (disambiguation).
"Anaconda" is often used to refer only to the green anaconda, Eunectes murinus.

Anacondas are large, nonvenomous boas of the genus Eunectes. They are found in tropical South America.

The most familiar species is the green anaconda, Eunectes murinus, notable for being one of the world's largest snakes. Green anacondas can grow to more than 5.21 m (17 ft) in length and weighing 97.5 kg (215 lb).[1] They are found east of the Andes in Colombia, Venezuela, the Guianas, Ecuador, Peru, Bolivia, Brazil, and on the island of Trinidad.

Other anacondas are the yellow anaconda, Eunectes notaeus, a smaller species found in eastern Bolivia, southern Brazil, Paraguay and northeastern Argentina, the dark-spotted anaconda, Eunectes deschauenseei, a rare species found in northeastern Brazil, coastal French Guiana and Guyana; and the Bolivian anaconda, Eunectes beniensis, discovered in 2002 in the flood plains of Bolivia's Pando province. It was the first new anaconda species identified since 1936, and became only the fourth known type of that reptile, according to the WWF.

All four species are aquatic snakes that prey on other aquatic animals, including fish, river fowl, caiman, and capybaras. Some accounts exist of anacondas preying on domestic animals such as goats[citation needed] and ponies[citation needed] that venture too close to the water.

While encounters between people and anacondas may be dangerous, they do not regularly hunt humans. Nevertheless, threat from anacondas is a familiar trope in comics, movies and adventure stories set in the Amazon jungle. Anacondas have also figured prominently in South American folklore, where they are sometimes depicted as shapeshifting mythical creatures called encantados. Local communities and some European explorers have given accounts of giant anacondas, legendary snakes of much greater proportion than any confirmed specimen.

Applied loosely, the term "anaconda" may also refer to any large snake that "crushes" its prey by constricting.
Etymology

The Merriam-Webster online dictionary states the word is probably a modification of the Sinhalese word henakandayā,which is used to refer to a small slender green whip snake found in Sri Lanka. However, certain other literature state henakandayā refers to a now extinct constrictor once found there. Richard Boyle (the Sri Lankan English consultant to the Oxford English Dictionary) writes in his book 'Sinbad In Serendib':
The first reference to the anaconda in English is by R. Edwin (probably a pseudonym) in a letter to the Scots magazine concerning an encounter with a tiger-devouring serpent in then Dutch-held Ceylon. This was published in the 1768 issue under the discursive heading, "Description of the ANACONDA, a monstrous species of serpent. In a letter from an English gentleman, many years resident in the island of Ceylon, in the East Indies."However, this account of an incident on the outskirts of Colombo is a figment of the imagination, full of the popular misconceptions regarding constrictors in an age of limited scientific knowledge of snakes.
—Richard Boyle

The Oxford English Dictionary gives a first source as John Ray's "List of Indian Serpents" from the Leyden Museum, as "anacandaia of the Ceylonese, i.e. he that crushes the limbs of buffaloes and yoke beasts," but that "anacandaia" is "not now a native name in Sri Lanka, and not satisfactorily explained either in Cingalese [Sinhalese] or Tamil"—though Henry Yule lists "āṇaik'k'onḍa" to means "having killed an elephant" in Tamil.

 
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