Nutria, Nutria Pictures, Nutria Facts - National Geographic Size relative to a 6-ft (2-m) man Please add a "relative" entry to your dictionary. Nutria are large, web-footed rodents that are more agile in the water than on land. They live in burrows, or nests, never far from the water. Nutria may inhabit a riverbank or lakeshore, or dwell in the midst of wetlands. They are strong swimmers and can remain submerged for as long as five minutes. Nutria (also called coypu) are varied eaters, most fond of aquatic plants and roots. They also feast on small creatures such as snails or mussels. Nutria can be rather social animals and sometimes live in large colonies, reproducing prolifically. Females have two or three litters every year, each consisting of five to seven young. These animals mature quickly and remain with their mothers for only a month or two. In some areas, booming nutria populations have become troublesome as the animals develop a taste for farm fare.

The nutria's yellow or brown outer hair looks shaggy and unappealing, but it covers a lush fur undercoat, also called nutria, that is popular for use in clothing. Nutria are farmed and trapped for this fur. Nutria once lived only in southern South America, but they have been domesticated as fur animals and transplanted around the world. In many areas, including Canada and more than a dozen U.S. states, fur farm escapees quickly establish large wild populations near their new homes. Nutria Facts Nutria Facts Nutria Facts Nutria, also known as coypu, is a species of rodent that is native to South America. This animal has been introduced to Europe, Asia and North America in the previous century because of its luxurious fur and potentially lucrative business associated with it. A lot of animals managed to escape from the farms and to conquer new habitats, such as swamps, wetlands, river mouths and drainage canals. Nutria can survive in all ecosystems that provide enough water. Due to high reproduction rate, nutrias act like invasive species that disturb natural balance in ecosystems. Nutria is not on the list of endangered species.

Interesting Nutria Facts: Nutria can reach 14 inches in length and 16 to 18 pounds in weight. It has 12 to 17 inches long tail. Nutria is covered with two types of fur. Outer coat is made of shaggy hair that can be yellow or brown in color. Next layer is made of fine, grey fur. This type of fur was very popular in fashion industry couple of decades ago. Nutria looks like a small beaver with long whiskers, short legs and hairless tail. Nutria has long incisors that are yellow to orange or orange to red in color. Nutria has five fingers on front and hind feet. All fingers except one on the front feet have long nails. Webbed hind feet represent adaptation to the life near the water. Nutria has valves in mouth and nose that close automatically when animal dives. They prevent water from entering the stomach and lungs. Nutria is semi-aquatic creature. That means that it spends half of its life in the water. Nutria is excellent swimmer that can spend 5 minutes under water without returning to the surface to breathe. Females can breastfeed their young during the swimming session.

Nutria digs burrows near the water or uses platforms made of dead vegetation to sleep, eat and reproduce. Nutria is nocturnal animal (active during the night). It is mostly active around midnight. Nutria is vegetarian that eats grass, roots, rhizomes and all kind of water plants. It will invade plantations of sugarcane, corn and rice whenever possible. Nutria has huge appetite. It can eat 25% of its own weight every day. Nutria mates throughout the whole year. Male has a harem composed of 2 to 3 females. Pregnancy in females lasts around 130 days and ends with usually 4 to 5 babies. Young nutrias are covered with fur from the moment of birth. Babies normally drink mother's milk during the first 8 weeks of their life, but they can survive on their own 5 days after birth if necessary. Females are able to reproduce 48h after delivering of babies. They have couple of litters each year, ensuring large number of nutria in the wild. Nutria can survive between 8 and 10 years in the wild.

Related Links: National Trappers Association - Nutria Nutria Order - Rodentia Family - Myocastor This member of the rodent family is native to South America, and it was introduced both accidentally and purposely in the waterways in several American states. The species has proved to be overly destructive of habitat in some areas, creating problems for muskrats and waterfowl. This species can tolerate winters in temperate areas only. An important furbearer in Louisiana and Texas coastal area, nutria are viewed as detrimental in most other areas. Adult nutria are about 24 inches long from the nose to the base of the tail. The tail itself is 12 to 17 inches long, round, and hairless. Coloration is brownish, and both sexes are similar in appearance and weight. The nutria is unique in that it has 3 sets or lengths of fur. Primary guard hairs are about 3 inches in length. Beneath this layer is the secondary guard hairs, which are more numerous and give the species its overall coloration. The underfur is short, and less dense than either a muskrat or beaver underfur. The whiskers on a nutria are obvious.

These whiskers are about 4 inches in length, and very numerous. Teeth number 20, and include 4 large incisors, and allows the nutria to cut off underwater plants without getting water into its mouth. The mouth also has glands located near the corners which produce oils that the nutria uses to comb and waterproof its fur. Nutria average 16 to 18 pounds in weight. Occasional individuals may weigh 25 pounds or more. Also unique is the location of the mammary glands on the females. The teats are locate high on the sides of the nutria, which allows young nutria to nurse as the mother swims in the water. Front feet have five toes, including a small toe corresponding to our thumb. Hind feet are much larger, and unique in that all toes are connected by a skin web except for the toe corresponding to our little toe. Nutria are apt to breed in any month of the year in North America. One male usually has 2 or 3 mates which share the same burrow. Female nutria mature at about 5 1/2 months of age, and female nutria usually have two litters per year.

Many females breed within two days after giving birth to a litter. Litter sizes vary according to a cycle. The first litter is small, with 2 to 4 being born. The second litter is larger with 4 to 6 offspring. The third litter is smaller than the second, and the fourth again increases in size. For one reason or another, each litter is either larger or smaller than the litter previous preceding it, and according to a pattern. If nutria litter sizes were averaged, five would probably be the average size. Female nutria are capable of producing only 6 litters as a rule. Females who produce seven litters in their lifetime are rare. Habits Nutria spend most of their time in or near the water. Although they are awkward and vulnerable on land the species will travel inland to feed upon preferred foods, including crops. Nutria are vegetarians and they do have large appetites. Primarily a surface feeder, nutria often overharvest favored foods, causing the production of less favored foods for themselves and other wildlife species. Nutria commonly cut off a preferred food near the waterline and swim or carry it to a feeding platform for eating.

These platforms are used most often during the trapping seasons, possibly because they are warmer on the nutria's hairless feet. Favored foods for nutria include rushes, reeds, cattails, arrowhead, square-stem spike rush and sawgrass. Sugarcane, alfalfa, corn and rice are also eaten if available Nutria are thought of as colonial because the same den is shared by the dominant male with two or three females and their offspring. Den entrances are often a foot or two beneath the water's surface, and the den entrance is often as much as two feet in diameter. The inner chamber of the den is above the waterline, and lined with grasses brought in to serve for bedding. This species is territorial and tolerant of others of its kind. Four or five colonies of nutria to the mile of levees or dikes indicates a high population as a family or colony territory is about 1,000 feet in length. Nutria do not remain underwater for long periods of time. Research shows that they are capable of holding their breath while submerged for about five minutes. A shy and retiring species, nutria are not usually seen unless there is a deliberate attempt to find them.

Nutria burrow into banks of ponds and lakes, and these holes are usually larger and more destructive than muskrat burrows. • Adult nutria are about 14 inches long with a 12-17-inch tail, and can weigh up to 25 pounds. • They have 20 teeth and 4-inch-long whiskers. • Female nutria have two litters of 4-6 offspring per year, but are only capable of producing 6 litters. They are capable of mating any month of the year. • A nutria is considered old if it reaches four years of age. Range Tracks and Scat The largest concentrations of nutria are in the southern coastal areas. Populations also occur in the eastern and northwestern coastal areas as well. General Nutria usually have a negative impact on other wildlife species. Because they are colonial in habitat, nutria often overharvest edible plants within their small range, resulting in the killing of the desirable plant species. These "eat-outs" destroy productivity as often less desirable plants replace the more desirable ones. Large populations of nutria definitely have a negative impact on the ability of the habitat to support both muskrats and waterfowl.

Nutria are preyed upon by alligators, cottonmouth moccasins, hawks, owls and eagles. Juveniles are usually most vulnerable to predation. Parasites include flatworms, roundworms, fleas and lice. The seeds of beggarstick also plague nutria as the barbed seeds entangle in the fur and puncture the skin, resulting in infections. The roundworms infesting nutria can cause health problems for man. The roundworm larvae is present in the water where nutria are found, and this larvae can penetrate human skin. Known as "nutria itch", severe inflammation can result, which requires medical attention. The sale of nutria furs is an important source of income for many trappers in regions where nutria are numerous. Most pelts are harvested in Louisiana, and around 2 million pelts are harvested annually. A nutria is considered as old at four years of age. How to Get Rid of Nutrias Advice and professional help for nutria problems. How to Get Rid of Nutrias The nutria, or coypu as it is also known, is not a native to North America.

Unfortunately, these animals that were once brought over with the intention of farming them for the fur trade have adapted amazingly well to the environment they found themselves in. Nutria are so acclimated now that they have become a nuisance animal on an extremely large scale in certain areas of the country. Herbivores, these animals feed on important wetland grasses and have wipe out hundreds of thousands of acres of protected wetlands in the south. Not only do coypus eat the vegetation needed to prevent erosion, they are extensive burrowers and often compromise the integrity of water dikes and levees with their tunnel systems. Nutria are not to be mistaken for muskrats. Both rodents have similar appearances, but the coypu has a rounded tail and the muskrat’s is flat. Need nutria removal in your hometown? Click here for my nationwide list of hundreds of wildlife removal experts , serving all 50 states! Updated year 2017. Deterrent Tactics: To get rid of nutria you’ll have to venture into its territory. This can mean wading into swamps and other watery areas. Accessibility is a big component to successful nutria removal.

If you cannot get into the area where the coypus are living, employing the use of floating rafts with set traps can be helpful. Nutria are not yard pests, so many of the deterrents on the market are not applicable to this animal. There are no decoys, chemical deterrents, or predator-based methods to eliminate this rodent. Property owners are not allowed to poison nutria, though licensed professional are given that option if they feel the situation warrants it. For the average person, most departments of wildlife control recommend the use of a fence to exclude coypus from your property. This fence needs to be buried at least a foot underground to prevent burrowing beneath it. It is also advised that the top portion be electrified and turned on at dawn and dusk when the rodents are most active. If you have a vast property this isn’t a very cost effective method of control. Contouring your banks to prevent burrows is also an option, but again, this will require the use of heavy machinery which may not be able to reach the problem habitats. Improving drainage is always an option as long as the body of water being affected isn’t a vital part of a large ecosystem.

Nutria Trapping: For most people, trapping and removing nutria is the most logical control method. Some states protect these animals because of their status as furbearing. Prior to trapping nutria, make sure you contact your local fish and game commission to see what permits and licenses are required. Once you know you are in the clear, decide if you wish to live trap or lethally trap the nutria. Often, when an animal is sizeable enough to warrant either type of trap, the number of creatures ultimately decides which method will be most effective. Live trapping is very good for one or two problem animals. If you have a large population of coypus, lethal trapping may be the most effective means of removal. Given the nuisance concerns surrounding nutria, live trapping and relocation is not always advised. Like most semi-aquatic animals, nutria can be trapped using leg hold traps like coilspring and longspring which are the most commonly used. These leg hold traps are placed near baited areas, often inside the pathways and channels created by frequent coypu usage. Drowning sets and body gripping traps are placed in areas of deeper water where the nutria must swim to get into runs and channels.

Both types of traps should be pre-baited prior to be set. Nutria are particularly fond of watermelon rinds, apples, carrots and potatoes. These bait foods are also vital for use with zinc phosphide, the only approved nutria toxicant available. Aside from trapping, shooting is considered an acceptable method of nutria control. Many areas have special shooting locations and season for harvesting coypus. Regardless of the nuisance and environmental concerns surrounding this non-native species, the revenue generated by nutria trapping and shooting is well into the multimillion dollar range annually. NUTRIA BIOLOGY AND INFORMATION: Nutria Appearance: Often confused with the muskrat, nutrias are larger, with round tails. They are not, however, as large as beavers, growing to be approximately fifteen pounds at three feet long. Nutrias are easily identified by a white patch of hair around their mouths as well as by their bright orange teeth. Like other semi-aquatic animals, nutrias are often brown, and their fur was once highly sought after. Similar to the coat of an otter, nutrias have a fine layer of fur guarded by a coarse layer on top providing insulation.

They have five toes on each paw, and the front feet are well designed for burrowing. The hind legs are longer than the front and boast webbed digits for better mobilization in the water. The nose and mouth of the nutria can be closed off while swimming underwater to prevent liquid intake. Another name for the nutria is coypu. Nutria Habitat and Behavior: Coypus are impressive burrowers, creating a network of tunnels in and out of embankments, though above-ground areas for grooming are often seen. They are semi-aquatic, and will build their homes off the edge of a river or stream. Burrow systems can range up to fifty feet in length and will usually house a family group of coypu rodents. Families are mostly female with one adult male. Young males will live alone until they can procure a mate and start their own family group. They prefer fresh water, though they will occupy man-made basins and canals. The nutria cannot tolerate cold temperatures like its cousin, the muskrat, so its distribution is not as widespread. Native to South America, it was brought north with the hope of raising the animal for food and fur purposes.

When the fur trade for coypu pelts went under, hundreds of the animals were released into the wild. Nutrias do not breed as abundantly as many other rodents. Females will give birth up to twice yearly, with offspring numbering around six. At four months of age, the coypu young are ready to breed on their own. At this age, males will move out and create their own nests. Burrows may be small at first, but will eventually grow to have multiple exits as well as intersecting tunnels. On occasion, groups of nutrias will migrate in cold weather. They are prone to frost bite on their tails, and the loss of a tail would result in an untimely death. When migrating, the animals appear awkward on the land, walking with a hunched posture due to longer hind legs. If threatened, they are surprisingly fast, and can move across dry land efficiently. Nutria Diet: Nutrias are herbivores. They feed on a variety of aquatic plants. In rare instances they will feed on mussels and bird eggs. Bark and roughage is a staple of the nutria’s diet.

Like all rodents, the front teeth grow continuously and must be kept at a reasonable length for the animal to be able to survive. Nutria Nuisance Concerns: Nutrias are not native to many parts of the world, and because of this invasive habitat change, they have caused widespread destruction through predation of vegetation. Coypus have devastated acres of wetlands. They eradicated the grasses needed to delay erosion in areas of the Louisiana coast, destroying over one hundred thousand acres of wetlands. In addition of wiping out species of aquatic grasses, the nutrias also destroyed eggs and nests of endangered birds. The coypu population in Louisiana alone was over two million at the height of the problem. Bounties were placed on nutria pelts to help quell the invasion of these rodents. Nutria Diseases: The most common disease associated with nutria is caused by strongyloides myopotami. This is nematode which causes “nutria rash” in people who handle the rodent. In reality, the rash is the nematode entering the skin and being attacked by the immune system. These rodents also carry leptospirosis, toxoplasmosis, and a host of other intestinal parasites.

SOME SPECIFIC NUTRIA AREAS OF INTEREST: How To Get Rid Of Nutria In Your Yard Though the nutria is not an animal that is considered a high risk as a pest, they do in some rare cases become annoyances. They can invade the yard if they find a source of food. If you have a plant like bamboo for example you may find it damaged one day because nutria can chew on it. Depending on the actual size of the nutria they may not even be deterred by dogs and traps may not be easy to find if at all. So how do you get rid of nutria in your yard? First you need to know what the incentive they have to come to the yard is and then remove it. If you are planning to trap the nutria or to use any other removal methods you should first become familiar with the laws regarding nutria in your area. Because they are an animal used for its fur there may be regulations on them or you may get paid for ‘harvesting’ them. Make sure to check into it as knowing what you can do can help you get rid of them quicker. How To Get Nutria From Your Basement Nutria in your basement can be one big scary surprise.

Nutria is not the type of animal you would expect to find in your basement because of its size, but the river rat will get in there and when that happens, you need to know how to get it out. The first thing to know is that you should not try to handle nutria with your bare hands. The rodent could bite and an infection can set which can become dangerous. The best thing to do to get the nutria out is to do so by using traps. When you look for traps it is important that you get the right size and bait. The size should be about 9x9 and about 32 inches deep. If the nutria is a bigger size then a bigger trap is needed. As far as the bait goes, you will need to place some inside the trap and some on the way leading to it. Some of the best bait that you could use to entice nutria is a combination of carrots and sweet potatoes. The traps are humane and depending on what you will be doing with the nutria you may decide to humanely dispose of them as well. Do not release them without checking with your local laws as they are a severe pest in most areas with a population.

How To Get Rid Of Nutria In Your River Banks If you have nutria in your river banks it can quickly become a pest that extends outside of the river and into your yard. They can reproduce fast and they can then cause damage to your yard and garden. Unfortunately there are also rules and laws that you have to know before you attempt to capture or move nutria; luckily most of them are favorable to you. Because you have them in your river bank it will be easier if they have just arrived. Giving Nutria a couple of months will make catching all of them almost impossible. So what is the best way to get rid of nutria in your river banks? If it is ok for you to trap and transport the nutria in your community, then the best thing to do would be to use traps. Traps must be gotten according to the size and the number of nutria that you are trying to catch. The bait of fresh fruits or vegetables can be used. Make sure to check with local laws as many areas want these pest animals removed. They are a fur-bearing animal so in some cases you would receive money for their tails or hides. What Diseases Do Nutria Carry?

One of the reasons that animal control professionals recommend that you do not touch nutria is because they can carry diseases which can in some cases be transmitted to humans. The first thing to remember is that nutrias are rodents and therefore they can get diseases which most rodents are exposed to. The first disease to be discussed is the nutria-itch or swimmer’s itch, which is transmitted through blood flukes and parasites. Scientists also believe that nutria can infect humans with a host of diseases, but the research is not complete as of yet on some of them. One of the biggest concerns when it comes to the diseases that nutrias carry comes from those with livestock. The reason for that fear is that the livestock will in some cases drink from the same water which is the habitat of the nutria. That water may be contaminated with feces and urine and that is how the disease can be transmitted. More research is being done to determine the chances of nutria infecting humans with leptospirosis, paratyphoid, hemorrhagic septicemia and others. © 2002-2017  Webmaster email  Residential & Commercial  Licensed & Insured Nutria, Invasive Species Council Priority Species Photograph: U.S.

Fish and Wildlife Service Photograph: Washington Department of Fish and Wildlife What are they? Nutria are medium sized rodents that live in freshwater environments. They are native to South America. Nutria can grow up to 40 inches from its nose to the tip of its round, rat-like tail. They weigh an average of 12 pounds, although some can reach up to 40 pounds. They are herbivores and feed primarily on the roots and stems of wetland plants. Are they here yet? Yes. Nutria were introduced into Washington for the fur-farming industry in the 1930s. By 1943, there were feral populations. Nutria are prolific breeders, capable of producing two litters a year. Populations are spreading rapidly throughout western Washington and are beginning now to appear in central Washington. Why should I care? Nutria will consume about 25 percent of their body weight each day. Because they eat the roots and stems of plants, they destroy about ten times more plant matter than they eat. Nutria have been known to turn riparian areas into muddy bogs, destroying marshes that provide protection for flooding and habit for other animals, birds, and fish.

Nutria often construct circular platforms of compacted vegetation, which they use for feeding, birthing, resting, and grooming. Nutria are known to construct burrows in levees, dikes, and embankments, causing bank collapse and erosion. They also are host to a variety of parasites and pathogens. What should I do if I find one? Report a sighting How can we stop them? At this time the Washington Department of Fish and Wildlife recommends that property owners contact a state-licensed trapper to capture and remove the animals. Any live-trapped nutria must be euthanized and not returned to the wild or transported within the state. What are their characteristics? Male and female nutria are very similar in appearance. The average adult is about 2 feet long from nose to the base of the tail. The rat-like, sparsely haired tail is 1-1.5 feet long. The fur of a nutria has three lengths. The short under fur is less dense than that of either a muskrat or beaver. The next layer is longer, more dense, and is the primary overall coloration of the species. The outer layer hairs are about 3 inches long.

Nutria’s whiskers are about 4 inches long. The front feet have five toes, one of which is a small toe akin to the human thumb. The hind feet are much larger and all the toes, except the one corresponding to the little toe in humans, are connected by a skin web for swimming. The nutria has glands near the corners of the mouth that produce oils the nutria uses to groom itself and waterproof its fur. The mammary glands on females are high on their sides, which allows their young to nurse while the mother is swimming. Nutria spend much of their time in water. Where can I get more information? Video: Following the invasive Video: Using Radio Telemetry to Track Nutria Movement Nutria Control - Trapping, removal, & damage prevention services Nutria Control Call us now at 1-888-488-1415 or contact us online. Nutria Nutria Facts Identification The nutria (Myocastor coypus, Fig. 1) is a large, dark-colored, semiaquatic rodent that is native to southern South America.

At first glance, a casual observer may misidentify a nutria as either a beaver (Castor canadensis) or a muskrat (Ondatra zibethicus), especially when it is swimming. This superficial resemblance ends when a more detailed study of the animal is made. Other names used for the nutria include coypu, nutria-rat, South American beaver, Argentine beaver, and swamp beaver. Nutria are members of the family Myocastoridae. They have short legs and a robust, highly arched body that is approximately 24 inches (61 cm) long. Their round tail is from 13 to 16 inches (33 to 41 cm) long and scantily haired. Males are slightly larger than females; the average weight for each is about 12 pounds (5.4 kg). Males and females may grow to 20 pounds (9.1 kg) and 18 pounds (8.2 kg), respectively. The dense grayish underfur is overlaid by long, glossy guard hairs that vary in color from dark brown to yellowish brown.

The forepaws have four welldeveloped and clawed toes and one vestigial toe. Four of the five clawed toes on the hind foot are interconnected by webbing; the fifth outer toe is free. The hind legs are much larger than the forelegs. When moving on land, a nutria may drag its chest and appear to hunch its back. Like beavers, nutria have large incisors that are yellow- orange to orange-red on their outer surfaces. In addition to having webbed hind feet, nutria have several other adaptations to a semiaquatic life. The eyes, ears, and nostrils of nutria are set high on their heads. Additionally, the nostrils and mouth have valves that seal out water while swimming, diving, or feeding underwater. The mammae or teats of the female are located high on the sides, which allows the young to suckle while in the water. When pursued, nutria can swim long distances under water and see well enough to evade capture. three Canadian provinces in North America since their introduction. About one-third of these states still have viable populations that are stable or increasing in number. Some of the populations are economically important to the fur industry.

Adverse climatic conditions, particularly extreme cold, are probably the main factors limiting range expansion of nutria in North America. Nutria populations in the United States are most dense along the Gulf Coast of Louisiana and Texas Habitat Nutria adapt to a wide variety of environmental conditions and persist in areas previously claimed to be unsuitable. In the United States, farm ponds and other freshwater impoundments, drainage canals with spoil banks, rivers and bayous, freshwater and brackish marshes, swamps, and combinations of various wetland types can provide a home to nutria. Nutria habitat, in general, is the semiaquatic environment that occurs at the boundary between land and permanent water. This zone usually has an abundance of emergent aquatic vegetation, small trees, and/or shrubs and may be interspersed with small clumps and hillocks of high ground. In the United States, all significant nutria populations are in coastal areas, and freshwater marshes are the preferred habitat. Food Habits Nutria are almost entirely herbivorous and eat animal material (mostly insects) incidentally, when they feed on plants. Freshwater mussels and crustaceans are occasionally eaten in some parts of their range.

Nutria are opportunistic feeders and eat approximately 25% of their body weight daily. They prefer several small meals to one large meal. The succulent, basal portions of plants are preferred as food, but nutria also eat entire plants or several different parts of a plant. Roots, rhizomes, and tubers are especially important during winter. Important food plants in the Range of the nutria introduced in North America. Range The original range of nutria was south of the equator in temperate South America. This species has been introduced into other areas, primarily for fur farming, and feral populations can now be found in North America, Europe, the Soviet Union, the Middle East, Africa, and Japan. M. c. bonariensis was the primary subspecies of nutria introduced into the United States. Fur ranchers, hoping to exploit new markets, imported nutria into California, Washington, Oregon, Michigan, New Mexico, Louisiana, Ohio, and Utah between 1899 and 1940. Many of the nutria from these ranches were freed into the wild when the businesses failed in the late 1940s.

State and federal agencies and individuals translocated nutria into Alabama, Arkansas, Georgia, Kentucky, Maryland, Mississippi, Oklahoma, Louisiana, and Texas, with the intent that nutria would control undesirable vegetation and enhance trapping opportunities. Nutria were also sold as “weed cutters” to an ignorant public throughout the Southeast. A hurricane in the late 1940s aided dispersal by scattering nutria over wide areas of coastal southwest Louisiana and southeast Texas. Accidental and intentional releases have led to the establishment of widespread and localized populations of nutria in various wetlands throughout the United States. Feral animals have been reported in at least 40 states and United States include cordgrasses (Spartina spp.), bulrushes (Scirpus spp.), spikerushes (Eleocharis spp.), chafflower (Alternanthera spp.), pickerelweeds (Pontederia spp.), cattails (Typha spp.), arrowheads (Sagittaria spp.), and flatsedges (Cyperus spp.). During winter, the bark of trees such as black willow (Salix nigra) and baldcypress (Taxodium distichum) may be eaten.

Nutria also eat crops and lawn grasses found adjacent to aquatic habitat. Because of their dexterous forepaws, nutria can excavate soil and handle very small food items. Food is eaten in the water; on feeding platforms constructed from cut vegetation; at floating stations supported by logs, decaying mats of vegetation, or other debris; in shallow water; or on land. In some areas, the tops of muskrat houses and beaver lodges may also be used as feeding platforms. GENERAL BIOLOGY, REPRODUCTION, & BEHAVIOR General Biology In the wild, most nutria probably live less than 3 years; captive animals, however, may live 15 to 20 years. Predation, disease and parasitism, water level fluctuations, habitat quality, highway traffic, and weather extremes affect mortality. Annual mortality of nutria is between 60% and 80%.

Predators of nutria include humans (through regulated harvest), alligators (Alligator mississippiensis), garfish (Lepisosteus spp.), bald eagles (Haliaeetus leucocephalus), and other birds of prey, turtles, snakes such as the cottonmouth (Agkistrodon piscivorus), and several carnivorous mammals. Nutria densities vary greatly. In Louisiana, autumn densities of about 18 animals per acre (44/ha) have been found in floating freshwater marshes. In Oregon, summer densities in freshwater marshes may be 56 animals per acre (138/ha). Sex ratios range from 0.6 to 1.6 males per female. In summer, nutria live on the ground in dense vegetation, but at other times of the year they use burrows. Burrows may be those abandoned by other animals such as armadillos (Dasypus novemcinctus), beavers, and muskrats, or they may be dug by nutria. Underground burrows are used by individuals or multigenerational family groups.

Burrow entrances are usually located in the vegetated banks of natural and human-made waterways, especially those having a slope greater than 45o. Burrows range from a simple, short tunnel with one entrance to complex systems with several tunnels and entrances at different levels. Tunnels are usually 4 to 6 feet (1.2 to 1.8 m) long; however, lengths of up to 150 feet (46 m) have been recorded. Compartments within the tunnel system are used for resting, feeding, escape from predators and the weather, and other activities. These vary in size, from small ledges that are only 1 foot (0.3 m) across to large family chambers that measure 3 feet (0.9 m) across. The floors of these chambers are above the water line and may be covered with plant debris discarded during feeding and shaped into crude nests. In addition to using land nests and burrows, nutria often build flattened circular platforms of vegetation in shallow water. Constructed of coarse emergent vegetation, these platforms are used for feeding, loafing, grooming, birthing, and escape, and are often misidentified as muskrat houses.

Initially, platforms may be relatively low and inconspicuous; however, as vegetation accumulates, some may attain a height of 3 feet (0.9 m). Reproduction Nutria breed in all seasons throughout most of their range, and sexually active individuals are present every month of the year. Reproductive peaks occur in late winter, early summer, and mid-autumn, and may be regulated by prevailing weather conditions. Under optimal conditions, nutria reach sexual maturity at 4 months of age. Female nutria are polyestrous, and nonpregnant females cycle into estrus (“heat”) every 2 to 4 weeks. Estrous is maintained for 1 to 4 days in most females. Sexually mature males can breed at any time because sperm is produced throughout the year. The gestation period for nutria ranges from 130 to 132 days. A postpartum estrus occurs within 48 hours after birth and most females probably breed again during that time. Litters average 4 to 5 young, with a range of 1 to 13. Litter sizes are generally smaller during winter, in suboptimal habitats, and for young females.

Females often abort or assimilate embryos in response to adverse environmental conditions. Young are precocial and are born fully furred and active. They weigh approximately 8 ounces (227 g) at birth and can swim and eat vegetation shortly thereafter. Young normally suckle for 7 to 8 weeks until they are weaned. Behavior Nutria tend to be crepuscular and nocturnal, with the start and end of activity periods coinciding with sunset and sunrise, respectively. Peak activity occurs near midnight. When food is abundant, nutria rest and groom during the day and feed at night. When food is limited, daytime feeding increases, especially in wetlands free from frequent disturbance. Nutria generally occupy a small area throughout their lives. In Louisiana, the home range of nutria is about 32 acres (13 ha). Daily cruising distances for most nutria are less than 600 feet (183 m), although some individuals may travel much farther. Nutria move most in winter, due to an increased demand for food. Adults usually move farther than young. Seasonal migrations of nutria may also occur.

Nutria living in some agricultural areas move in from marshes and swamps when crops are planted and leave after the crops are harvested. Nutria have relatively poor eyesight and sense danger primarily by hearing. They occasionally test the air for scent. Although they appear to be clumsy on land, they can move with surprising speed when disturbed. When frightened, nutria head for the nearest water, dive in with a splash, and either swim underwater to protective cover or stay submerged near the bottom for several minutes. When cornered or captured, nutria are aggressive and can inflict serious injury to pets and humans by biting and scratching. DAMAGE AND DAMAGE IDENTIFICATION Kinds of Damage Nutria damage has been observed throughout their range. Most damage is from feeding or burrowing. In the United States, most damage occurs along the Gulf Coast of Louisiana and Texas. The numerous natural and human-made waterways that traverse this area are used extensively for travel by nutria. Burrowing is the most commonly reported damage caused by nutria. Nutria are notorious in Louisiana and Texas for undermining and breaking through water-retaining levees in flooded fields used to produce rice and crawfish. Additionally, nutria burrows sometimes weaken flood control levees that protect low-lying areas.

In some cases, tunneling in these levees is so extensive that water will flow unobstructed from one side to the other, necessitating their complete reconstruction. Nutria sometimes burrow into the styrofoam flotation under boat docks and wharves, causing these structures to lean and sink. They may burrow under buildings, which may lead to uneven settling or failure of the foundations. Burrows can weaken roadbeds, stream banks, dams, and dikes, which may collapse when the soil is saturated by rain or high water or when subjected to the weight of heavy objects on the surface (such as vehicles, farm machinery, or grazing livestock). Rain and wave action can wash out and enlarge collapsed burrows and compound the damage. Nutria depredation on crops is well documented. In the United States, sugarcane and rice are the primary crops damaged by nutria. Grazing on rice plants can significantly reduce yields, and damage can be locally severe. Sugarcane stalks are often gnawed or cut during the growing season. Often only the basal internodes of cut plants are eaten.

Other crops that have been damaged include corn, milo (grain sorghum), sugar and table beets, alfalfa, wheat, barley, oats, peanuts, various melons, and a variety of vegetables from home gardens and truck farms. Nutria girdle fruit, nut, and shade trees and ornamental shrubs. They also dig up lawns and golf courses when feeding on the tender roots and shoots of sod grasses. Gnawing damage to wooden structures is common. Nutria also gnaw on styrofoam floats used to mark the location of traps in commercial crawfish ponds. At high densities and under certain adverse environmental conditions, foraging nutria can significantly impact natural plant communities. In Louisiana, nutria often feed on seedling baldcypress and can cause the complete failure of planted or naturallyregenerated stands. Overutilization of emergent marsh plants can damage stands of desirable vegetation used by other wildlife species and aggravate coastal erosion problems by destroying vegetation that holds marsh soils together. Nutria are fond of grassy arrowhead (Sagittaria platyphylla) tubers and may destroy stands propagated as food for waterfowl in artificial impoundments.

Nutria can be infected with several pathogens and parasites that can be transmitted to humans, livestock, and pets. The role of nutria, however, in the spread of diseases such as equine encephalomyelitis, leptospirosis, hemorrhagic septicemia (Pasteurellosis), paratyphoid, and salmonellosis is not well documented. They may also host a number of parasites, including the nematodes and blood flukes that cause “swimmer’s-itch” or “nutria-itch” (Strongyloides myopotami and Schistosoma mansoni), the protozoan responsible for giardiasis (Giardia lamblia), tapeworms (Taenia spp.), and common liver flukes (Fasciola hepatica). The threat of disease may be an important consideration in some situations, such as when livestock drink from water contaminated by nutria feces and urine. Damage Identification The ranges of nutria, beavers, and muskrats overlap in many areas and damage caused by each may be similar in appearance. Therefore, careful examination of sign left at the damage site is necessary to identify the responsible species.

On-site observations of animals and their burrows are the best indicators of the presence of nutria. Crawl outs, slides, trails, and the exposed entrances to burrows often have tracks that can be used to identify the species. The hind foot, which is about 5 inches (13 cm) long, has four webbed toes and a free outer toe. A drag mark left by the tail may be evident between the footprints. Droppings may be found floating in the water, along trails, or at feeding sites. These are dark green to almost black in color, cylindrical, and approximately 2 inches (5 cm) long and 1/2 inch (1.3 cm) in diameter. Additionally, each dropping usually has deep, parallel grooves along its entire length. Trees girdled by nutria often have no tooth marks, and bark may be peeled from the trunk. The crowns of seedling trees are usually clipped (similar to rabbit [Sylvilagus spp.] damage) and discarded along with other woody portions of the plant. In rice fields, damage caused by nutria, muskrats, and Norway rats (Rattus norvegicus) can be confused.

Nutria and muskrats damage rice plants by clipping stems at the water line in flooded fields; Norway rats reportedly clip stems above the surface of the water (E. A. Wilson, personal communication). Legal Status Nutria are protected as furbearers in some states or localities because they are economically important. Permits may be necessary to control animals that are damaging property. In other areas, nutria have no legal protection and can be taken at any time by any legal means. Consequently, citizens experiencing problems with nutria should be familiar with local wildlife laws and regulations. Complex problems should be handled by professional wildlife damage control specialists who have the necessary permits and expertise to do the job correctly. Your state wildlife agency can provide the names of qualified wildlife damage control specialists and information on pertinent laws and regulations. Damage Prevention and Control Methods Preventive measures should be used whenever possible, especially in areas where damage is prevalent. When control is warranted, all available techniques should be considered before a control plan is implemented. The objective of control is to use only those techniques that will stop or alleviate anticipated or ongoing damage or reduce it to tolerable levels. In most cases, successful control will depend on integrating a number of different techniques and methods.

Timing and location of control activities are important factors governing the success or failure of any control project. Control in sugarcane, for example, is best applied during the growing season, after damage has started. At this time, nutria in affected areas are relatively stationary and concentrated in drainages adjacent to fields. Conversely, efforts to protect rice field levees or the shorelines of southern lakes and ponds should be initiated during the winter when animals are mobile and concentrated in major ditches and other large bodies of water. Nutria are best controlled where they are causing damage or where they are most active. Baiting is sometimes used to concentrate nutria in specific locations where they can be controlled more easily. After the main concentrations of nutria are removed, control efforts should be directed at removing wary individuals. Exclusion Fences, walls, and other structures can reduce nutria damage, but high costs usually limit their use. As a general rule, barriers are too expensive to be used to control damage to agricultural crops. Low fences (about 4 feet [1.2 m]) with an apron buried at least 6 inches (15 cm) have been used effectively to exclude nutria from home gardens and lawns.

Sheet metal shields can be used to prevent gnawing damage to wooden and styrofoam structures and trees. Barriers constructed of sheet metal can be expensive to erect and unsightly. Protect baldcypress and other seedlings with hardware cloth tubes around individual plants or wire mesh fencing around the perimeter of a stand. Extensive use of these is neither practical nor cost-effective. Plastic seedling protectors are not effective in controlling damage to baldcypress seedlings because nutria can chew through them. Sheet piling, bulkheads, and riprap can effectively protect stream banks from burrowing nutria. Installation requires heavy equipment and is expensive. Use is usually restricted to industrial or commercial applications. Cultural Methods and Habitat Modification Land that is well-drained and free of dense, weedy vegetation is generally unattractive to nutria. Use of other good farming practices, such as precision land leveling and weed management, can minimize nutria damage in agricultural areas. Draining and Grading. Any drainage that holds water can be used by nutria as a travel route or home site. Consequently, eliminate standing water in drainages to reduce their attractiveness to nutria.

This may be extremely difficult or impossible to accomplish in low-lying areas near coastal marshes and permanent bodies of water. Higher sites, such as those used for growing sugarcane and other crops, are better suited for this type of management. On poorly drained soils, contour small ditches to eliminate low spots and sills and enhance rapid drainage. Use precision leveling on well-drained soils to eliminate small ditches that are occasionally used by nutria. Grading and bulldozing can destroy active burrows in the banks of steepsided ditches and waterways. In addition, contour bank slopes at less than 45o to discourage new burrowing. Sculpting rice field levees to make them gently sloping is similarly effective. Continued deep plowing of land undermined by nutria can destroy shallow burrow systems and discourage new burrowing activity. Vegetation Control Eliminate brush, trees, thickets, and weeds from fence lines and turn rows that are adjacent to ditches, drainages, waterways, and other wetlands to discourage nutria. Burn or remove cleared vegetation from the site. Brush piles left on the ground or in low spots can become ideal summer homes for nutria.

Water Level Manipulation Many low-lying areas along the Gulf Coast are protected by flood control levees and pumps that can be used to manipulate water levels. By dropping water levels during the summer, stressful drought conditions that cause nutria to concentrate in the remaining aquatic habitat can be simulated, thus increasing competition for food and space, exposure to predators, and emigration to other suitable habitat. Raising water levels in winter will force nutria out of their burrows and expose them to the additional stresses of cold weather. Water level manipulation is expensive to implement and has not yet been proven to be effective. Nevertheless, this method should be considered when a comprehensive nutria control program is being developed. Other Cultural Methods Alternate field and garden sites should be considered in areas where nutria damage has occurred on a regular basis. New fields, gardens, and slab-on-grade buildings should be located as far as possible from drainages, waterways, and other water bodies where nutria live. Late-planted baldcypress seedlings are less susceptible to damage by nutria than those planted in the spring. For this reason, plant unprotected seedlings in the early fall when alternative natural foods are readily available. Frightening Nutria are wary creatures and will try to escape when threatened.

Loud noises, high pressure water sprays, and other types of harassment have been used to scare nutria from lawns and golf courses. The success of this type of control is usually short-lived and problem animals soon return. Consequently, frightening as a control technique is neither practical nor effective. Repellents No chemical repellents for nutria are currently registered. Other rodent repellents (such as Thiram) may repel nutria, but their effectiveness has not been determined. Use of these without the proper state and federal pesticide registrations is illegal. Toxicants Zinc phospide is the only toxicant that is registered for controlling nutria. Zinc phosphide is a Restricted Use Pesticide that can only be purchased and applied by certified pesticide applicators or individuals under their direct supervision. It is a grayish-black powder with a heavy garlic-like smell and is widely used for controlling a variety of rodents. When used properly, zinc phosphide poses little hazard to nontarget species, humans, pets, or livestock. Zinc phosphide is highly toxic to wildlife and humans, so all precautions and instructions on the product label should be carefully reviewed, understood, and followed precisely.

Use an approved respirator and wear elbowlength rubber gloves when handling this chemical to prevent accidental poisoning. Mix and store baits treated with zinc phosphide only in wellventilated areas to reduce exposing humans to chemical fumes and dust. When possible, mix zinc phosphide at the baiting site to avoid having to store and transport treated baits. Never transport mixed bait or open zinc phosphide containers in the cab of any vehicle. Store unused zinc phosphide in a dry place in its original watertight container because moisture causes it to deteriorate. Immediately wash off any zinc phosphide that gets on the skin. Past studies have shown that zinc phosphide can kill over 95% of the nutria present along waterways when applied to fresh baits at a 0.75% (7,500 ppm) rate. Today, the use of zinc phosphide at this concentration is illegal. Federal and state registrations, however, allow lower rates to be used. For example, the label held by USDAAPHIS- ADC (EPA Reg. No. 56228-9) allows for a maximum 0.67% (6,700 ppm) treatment rate.

At this rate, approximately 94 pounds (42.7 kg) of bait can be treated with 1 pound (0.4 kg) of 63.2% zinc phosphide concentrate. Where to Bait The best places to bait nutria are in waterways, ponds, and ditches where permanent standing water and recent nutria sign are found. Baiting in these areas increases efficiency and reduces the likelihood that nontarget animals will be affected. Small chunks of unpeeled carrots, sweet potatoes, watermelon rind, and apples can be used as bait. The best baiting stations for large waterways are floating rafts spaced 1/4 to 1/2 mile (0.4 to 0.8 km) apart throughout the damaged area. In ponds, use one raft per 3 acres (1.2 ha).

Rafts measuring 4 feet (1.2 m) square or 4 x 8 feet (1.2 x 2.4 m) are easily made from sheets of 3/8- to 3/4-inch (1.0- to 1.9- cm) exterior plywood and 3-inch (7.6-cm) styrofoam flotation. Install a thin wooden strip around the perimeter of the raft’s surface to keep bait from rolling into the water. The raft should float 1 to 4 inches (2.5 to 10.2 cm) above the surface and should be anchored to the bottom with a heavy weight or tied to the shore. In small ditches or areas where nutria densities are low, use 6-inch (15.2-cm) square floating bait boards made of wood and styrofoam, in lieu of rafts. These can be maintained in place with a long slender anchoring pole made of bamboo, reed, or other suitable material that is placed through a hole in the center of the platform. This allows the board to move up and down as water levels change. Attach baits to small nails driven into the surface of the platform.

Bait boards should be spaced 50 to 100 feet (15.2 to 30.5 m) apart in areas where nutria are active. Other natural sites surrounded by water can also be baited for nutria. Small islands, exposed tree stumps, floating logs, and feeding platforms are excellent baiting sites. Avoid placing baits on muskrat houses and beaver lodges. Baits can be attached to trees, stumps, or other structures with small nails and should be kept out of the water. Baiting on the ground should only be used when water sites are unsuitable or lacking. Ground baiting is justified and effective when eliminating the last few nutria in a local population. Use care when ground baiting because baits may be accessible to nontarget animals and humans. Place ground baits near sites of nutria activity, such as trails and entrances to burrows. Prebaiting. Prebaiting is a crucial step when using zinc phosphide because it leads to nutria feeding at specific sites on specific types of food (such as the baits; carrots or sweet potatoes are preferred).

Nutria tend to be communal feeders, and if one nutria finds a new feeding spot, other nutria in the area will also begin feeding there. To prebait, lightly coat small (approximately 2-inch [5.1-cm] long) chunks of untreated bait with corn oil. Place the bait at each baiting station in late afternoon, and leave it overnight. Use no more than 10 pounds (4.5 kg) of bait per raft, 4 pieces of bait per baiting board, or 2 to 5 pieces at other sites at one time. Prebaiting should continue at least 2 successive nights after nutria begin feeding at a baiting site. Large Fig. 5. Examples of a 4-foot (1.2-m) square raft (left) and a 6-inch (15.2-cm) square baiting board, which are used to concentrate nutria for shooting, trapping, or poisoning. These baiting platforms are constructed of plywood and styrofoam and baited with sweet potatoes. More than 1 week gaps in the prebaiting sequence necessitate that the process be started over.

Observations of prebaited sites will help you decide how the control program should proceed. If nontarget animals are feeding at these sites (as determined by sign or actual observations of animals), then prebaiting should start over at another location. Prepare and apply zinc phosphidetreated baits when nutria become regular users of prebaited baiting stations and nontarget animals are not a problem. Applying Zinc Phosphide Prepare zinc phosphide baits as needed to prevent deterioration. Treated baits are prepared in 10-pound (4.5-kg) batches (enough to treat one raft) by using the following ingredients: 10 pounds (4.5 kg) of bait (carrots or sweet potatoes are preferred), prepared as for prebaiting; 1 fluid ounce or 2 tablespoons (30 ml) of corn oil; and 1.7 ounces or 7.5 tablespoons (48.2 g) of 63.2% zinc phosphide concentrate. To prepare treated baits, add corn oil to the bait in a 5 gallon (18.9 l) plastic or metal container.

Stir the mixture until the bait is lightly coated with corn oil. Sprinkle zinc phosphide over the mixture and stir until the bait is uniformly coated. Treated baits have a shiny black appearance and should be dried for about 1 hour in a wellventilated area until the color changes to a dull gray. Properly dried baits are weather-resistant and remain toxic until they deteriorate. Although treated baits can survive light rain, they should not be used when heavy rains are expected or on open water that is subject to heavy wave action. The amount of untreated bait eaten the last night of prebaiting determines how much treated bait should be used on the first night. When all or most of the untreated prebait is gone from baiting stations by morning, the same amount of treated bait is used on the stations the following night (e.g., up to 10 pounds [4.5 kg] per raft, 4 pieces per baiting board, and 2 to 5 pieces at other sites). When smaller quantities are eaten, reduce the amount of treated bait that is used per station proportionately.

When only a few pieces of prebait on a raft are eaten, the raft should be removed and replaced with several scattered baiting boards. The quantity of treated bait eaten each treatment night is the quantity that should be put out the following afternoon. Continue baiting until no more bait is being taken. Most nutria can be controlled after 4 nights of baiting. When densities are high, control may require more time. Post-Control Procedures Usually only 25% of the poisoned nutria die where they can be found. Many nutria die in dens, dense vegetation, and other inaccessible areas. Carcasses of nutria killed with zinc phosphide should be collected as soon as possible and disposed of by deep burial or burning to prevent exposure of domestic and wild scavengers to undigested stomach material containing zinc phosphide. Dispose of any leftover treated bait in accordance with label directions. Cessation of damage is the best indicator that zinc phosphide is controlling problem animals. You can quantify the reduction in nutria activity by putting out untreated bait at baiting stations after the last application of zinc phosphide. The amount eaten at this time is compared to the amount of bait eaten on the last night of prebaiting.

Fumigants Several fumigants are registered for controlling burrowing rodents but none are registered for use against nutria. Some, such as aluminum phosphide, may have potential as nutria control agents, but their efficacy has not been scientifically demonstrated. Carbon monoxide gas pumped into dens has reportedly been used to kill nutria, but this method is neither practical nor legal because it is not registered for this purpose. Trapping Commercial Harvest Damage to crops, levees, wetlands, and other resources is minimal in areas where nutria are harvested by commercial trappers. The commercial harvest of nutria on private and public lands should be encouraged as part of an overall program to manage nutriacaused damage. Landowners may be able to obtain additional information on nutria management, trapping, and a list of licensed trappers in their area from their state wildlife agency. Leghold traps Leghold traps are the most commonly used traps for catching nutria. Double longspring traps, No. 11 or 2, are preferred by most trappers; however, the No. 1 1/2 coilspring, No. 3 double longspring, or the soft-catch fox trap can also be used effectively.

Legholds are more efficient and versatile than body-grip traps and are highly recommended for nutria control work. Leghold traps should be used with care to prevent injury to children and pets. Several ways of setting leghold traps are effective. Set traps just under the water where a trail enters a ditch, canal, or other body of water. Make trail sets by placing a trap offset from the trail’s center line so that nutria are caught by the foot. Traps can be lightly covered with leaves or other debris to hide them, but nutria are easily captured in unconcealed traps. Bait can be used to lure nutria to leghold sets. Nutria use their teeth to pick up large pieces of food; therefore, bait should be placed beside, rather than inside, the trap jaws. Leghold traps are also effective when set on floating rafts that have been prebaited for a short period of time. Use drowning sets when deep water is available. Otherwise, stake leghold traps to the ground, or anchor them to solid objects in the water or on land (such as floating logs, stumps, or trees and shrubs).

Nutria caught in nondrowning leghold sets should be humanely dispatched with a shot or hard blow to the head. Nontarget animals should be released. Live Traps Nutria are easily captured in single- or double-door live traps that measure 9 x 9 x 32 inches (22.8 x 22.8 x 81.3 cm) or larger. Use these when leghold and body-grip traps cannot be set or when animals are to be translocated. Bait live traps with sweet potatoes and carrots and place them along active trails or wherever nutria or their sign are seen. A short line of baits leading to the entrance of a live trap will increase capture success. Live traps placed on floating rafts will effectively catch nutria but prebaiting is necessary. A large raft can hold up to 8 traps. Unwanted nutria should be destroyed with a shot or blow to the head. Nontarget animals should be released. Floating, drop-door live traps catch nutria but are bulky and cumbersome to use. The same is true for expensive suitcase-type beaver traps. Unwary nutria can be captured using a longhandled dip net.

This method should only be used by trained damage control professionals who should take special precautions to prevent being bitten or clawed. Live nutria can be immobilized with an injection of ketamine hydrochloride. Funnel traps are not effective for controlling nutria. Place set snares in trails and other travel routes, feeding lanes, trails, and bank slides. Snares do not kill the animals they catch, so anchor the snare securely. Check snares frequently because they are often knocked down by nutria and other animals. Snared nutria should be dispatched with a shot or blow to the head. Release any nontarget animals that are captured. Shooting Shooting can be used as the primary method of nutria control or to supplement other control techniques. Shooting is most effective when done at night with a spotlight, however, night shooting is illegal in many states and should not be done until proper permits have been obtained. Once shooting has been approved by the proper authorities, nutria can be shot from the banks of waterways and other bodies of water or from boats.

In some cases, 80% of the nutria in an area can be removed by shooting with a shotgun or small caliber rifle, such as the .22 rimfire. Care should be taken when shooting over open water to prevent bullets from ricocheting. Shooting at Bait Stations Baits can attract large numbers of nutria to floating rafts, baiting boards, and other areas where they can be shot. Shooting from dusk to about 10:00 p.m. for 3 consecutive nights is effective once a regular feeding pattern has been established. Feeding sites should be lit continuously by a spotlight and easily visible to the shooter from a vehicle or other stationary blind. At night, nutria can be located by their red-shining eyes and the V-shaped wake left by swimming animals. As many as 4 to 5 nutria per hour may be taken by this method. Shooters should wait 2 to 3 weeks before shooting nutria at the same site again. Boat Shooting Shooting can also be done in the late afternoon or early evening from a small boat paddled slowly along waterways and large ditches or along the shores of small lakes and ponds.

Nutria are especially vulnerable to this method when water levels are extremely high or vegetative Body-gripping Traps. The Conibear® trap, No. 220-2, is the most commonly used body-gripping trap for controlling nutria. Nos. 160-2 and 330-2 Conibear® traps can also be used. Place sets in trails, at den entrances, in culverts, and in narrow waterways. Large body-grip traps can be dangerous and should be handled with extreme caution. These traps should not be set in areas frequented by children, pets, or desirable wildlife species. Other Traps Use locking snares to catch nutria when other traps cannot be set. Snares are relatively easy to set, safer than leghold and body-grip traps, and almost invisible to the casual observer. Snares constructed with 3/32-inch (0.2-cm) diameter, flexible (7 x 7-winding) stainless steel or galvanized aircraft cable are suitable for catching nutria.

Ready-made snares and components (for example, cable, one-way cable locks, swivels, and cable stops) for making homemade snares can be purchased from trapping suppliers. cover is scarce. At times, animals can be stimulated to vocalize or decoyed to a boat or blind by making a “maw” call, which imitates the nutria’s nocturnal feeding and assembly call. This call can be learned from someone who knows it or by listening to nutria vocalizations at night. Nutria become wary quickly, so limit shooting to no more than 3 nights, followed by 2 to 3 weeks of no activity. Bank Shooting Nutria can be shot by slowly stalking along the banks of ditches and levees; this can be an effective control method where nutria have not been previously harassed. Unlike night shooting from a boat or blind, bank shooting is most effective at twilight, both in the evening and morning. Several nutria can usually be shot the first night, however, success decreases with each successive night of shooting. Daytime shooting from the bank of a waterway is effective in some situations. Economics of Damage and Control Nutria can have either positive or negative values.

They are economically important furbearers when their pelts provide income to commercial trappers. Conversely, they are considered pests when they damage property. From 1977 to 1984, an average of 1.3 million nutria pelts were harvested annually in the United States. Based on prices paid to Louisiana trappers during this period, these pelts were worth about $7.3 million. The estimated value of sugarcane and rice damaged by nutria each year has ranged from several thousand dollars to over a million dollars. If losses of other resources are added to this amount, the estimated average loss would probably exceed $1 million annually. Management plans developed for nutria should be comprehensive and should consider the needs of all stakeholders. Regulated commercial trapping should be an integral part of any management scheme because it can provide continuous, long-term income to trappers; maintain acceptable nutria densities; and reduce damage to tolerable levels. The value of the protected resource must be compared with the cost of control when determining whether nutria control is economically feasible. Most people will not control nutria if costs exceed the value of the resource being protected or if control will adversely impact income derived from trapping.

Of course, there are exceptions, especially when the resource has a high sentimental or aesthetic value to the owner or user. *The above information was taken from a University of Nebraska Web site with express permission of Stephen Vatassel, wildlife damage project coordinator. Click here to see our Can dog food help Louisiana's wetlands? Can dog food help Louisiana's wetlands? <iframe src="" frameborder="0" width="100%" height="240px"></iframe> Copy Close Robert Raymond captures 2,000 nutrias a year. - Noam Eshel Robert Raymond is a nutria's biggest nightmare. The retired trapper captures almost 2,000 of the 15-pound, invasive, coastal-wetlands-destroying mammals every year. The state of Louisiana relies on people like Raymond to keep the wild nutria population under control. The bad news is, trappers like Raymond are a dying breed. A Business Opportunity Gone Wild Nutria damage thousands of acres of coastal wetlands in Louisiana each year. Originally from South America where they are called Coypu, the rodents were introduced to Louisiana in the 1930s to supplement the state's booming fur market.

Marketers peddled the creatures as a get-rich scheme -- cultivate them, sell the fur, make a fortune! They even came up with a new name: “nutria.” That translates in Spanish as “otter,” an animal with a prized coat in the fur industry at the time. A nutria in Ljubljanica, Slovenia. (Source: Petar Milošević / Wikimedia Commons) The newly christened beasts soon escaped into Louisiana's coastal marshland where they thrived, earning them another name: “river rat.” An apt one; the creatures are essentially marsh lawnmowers, scarfing down vegetation and leaving the coastal wetlands increasingly susceptible to erosion. A robust fur market and Louisiana's trapping tradition once kept the feral nutria population in check. Today, that's no longer the case. Edmond Mouton directs the nutria control program for the Louisiana Department of Fish and Wildlife. He says trapping was once standard work in the winter for crabbers, shrimpers, and fishermen. “It was kind of the lifestyle of the coastal people,” Mouton says, “and a lot of that has since gone by the wayside.” Why? Money.

At the height of the fur market in the '70s, Mouton says nutria pelts used to go for $9 a piece. There were about 15,000 trappers in the state back then he says, and they brought in two million nutria a year. Now the price of nutria fur is down to around $2 a pelt, and the number of trappers to about 2,000. As the trappers dropped off, the nutria population bloomed. Mouton says estimates for the number of nutria in the mid-'90s range to over 25 million. The rodents were chewing up the wetlands. A dozen years ago the state started offering a bounty for a dead nutria. It started at $4 for a tail and has since risen to $5. Mouton says, “the idea behind the program is to create an artificial inflated price to emulated a good fur market.” So far the initiative has been pretty successful. Trappers are bringing in around 320,000 nutria a year. But it comes at a cost -- about $3 million in state and federal funds.

The dream is to bring back a market for the creature. Searching for an Alternative Market Louisiana has promoted nutria as eco-friendly fur and ran a campaign to convince people they are culinary delicacies. Perhaps it's because of the association with rats, or those teeth -- protruding out from their mouths like two, tobacco-stained daggers -- but for whatever reason, neither the food nor the fur concept has taken off. That brings us to the dogs. “Maybe it's the wild taste of it,” Veni Harlan says, “but they absolutely go crazy over it.” Veni Harlan and her brother Hansel have a new business plan for nutria: protein-rich, allergen-free, locally-sourced, and very eco-conscious dog treats. Their company is called Marsh Dog . On their packages they tout the biscuits and jerky as “good for your dog and great for coastal wetlands.” Hansel Harlan says they aim to create a market that will encourage people to trap more nutria. “It's sort of harnessing the forces of capitalism to address a larger good,” he says. Achieving that larger good means eradicating nutria, which, Veni admits, puts them in a funny position as a business.

“Well, our goal,” Veni says, “would be to be put out of business.” With several million nutria running around the state, they won't be disappearing anytime soon. Especially if trappers like Raymond really start retiring. Sam tweeted about the backstory of his reporting. Follow him at @SamWHarnett . Nutria Rat Destroying Louisiana - Business Insider The nutria is a large rodent that looks like a large rat or a beaver. Wikipedia Oh rats. A very large rodent that looks like a beaver with a rat-like tail is destroying coastal Louisiana, chomping its way through the state's wetland vegetation and removing the plants and grasses that are critical to preventing these marshes from turning into open water. The nutria, a web-footed animal with shaggy, brown outer fur and large, orange teeth, is originally from South America. The swamp creature was brought to the United States in the early 19th century and farmed for its fur. But as fur declined in popularity over the next century, many farms were shut down. Some animals were released into the wild by their owners, others are believed to have escaped.

By the 1950s, there were around 20 million nutria running around coastal Louisiana , according to the U.S. Geological Survey. Today that number has been vastly reduced thanks to a series of efforts to control overpopulation , including a $4 bounty on each nutria tail and an extensive trapping and harvest program. There is also a growing market for nutria meat, which is high in protein. The large rodents have voracious appetites, which in turn, is destroying Louisiana's wetland vegetation. Wikipedia Documentary filmmaker Chris Metzier, who is currently making a movie about nutria called "Rodents of Unusual Size" (taken from the name of creatures that lived in the fire swamp in "The Princess Bride"), said in an interview with Take Part that the Louisiana nutria population is presently around 5 million . Nutria are known for their hearty appetite and remain a serious threat to Louisiana's wetlands because they feed on the roots of plants. Without the root system to hold the soil together, the land becomes even more vulnerable to erosion and flooding. The Louisiana government estimates that at any one point in time, nutria impact more than 46,000 acres of Louisiana's coastal wetlands.

The silver lining is that that number is down from 80,000 acres, before nutria-control methods were implemented in 2002 .

Question: What sort of creature is a coypu?
Answer: Rodent