Bal-chatri are traps designed to catch birds of prey. The trap consists of a cage baited inside with a conspicuously visible live rodent or small bird, with a series of monofilament nooses attached to the surface to snare the legs of a free-flying raptor that attempts to take the bait; the name is derived from the Hindi word used by trappers in India. Modified bal-chatri traps are used for catching shrikes; the bal-chatri originated in East India as a trap developed and used by falconers to catch suitable birds of prey to train for use in hunting. It consisted of a small, cane cage, containing live lure birds to attract raptors, covered with attached horsehair nooses to entangle their feet; the term bal-chatri has been mistranslated as “boy’s umbrella”, or “small umbrella”, after their shape but is translated to "hair umbrella" and refers to the nooses made of horse-hair anchored to the umbrella-like frame. Bal-chatris continue to be used by falconers, but are used in ornithological research projects which require the capture of raptors for banding and other procedures, such as blood sampling.
Contemporary traps are made of more modern materials, such as wire mesh cages with nooses made of nylon monofilament. The traps vary from 25 -- 50 cm with the nooses 4 -- 12 cm in diameter, they are weighted to prevent them from being carried away by ensnared birds. The live lure, or bait, animals used for the trap are rodents such as house mice; the cage may have a double wall, or a removable roof or inner compartment, both to protect the bait animals from the raptors, to prevent them damaging the nooses by chewing them. The traps are designed to be portable and may be deployed opportunistically from a moving vehicle on a roadside when a hawk or falcon is sighted perch-hunting from a pole or utility line along a road, they may be used near nesting sites in order to trap a breeding pair. Active traps require continuous monitoring. Users require proper training. Hamerstrom, Frances.. Birding with a Purpose: Of Raptors and Other Creatures. Blackwell Publishing. ISBN 978-0-8138-0229-9
Squirrels are members of the family Sciuridae, a family that includes small or medium-size rodents. The squirrel family includes tree squirrels, ground squirrels, marmots, flying squirrels, prairie dogs amongst other rodents. Squirrels are indigenous to the Americas and Africa, were introduced by humans to Australia; the earliest known squirrels date from the Eocene period and are most related to the mountain beaver and to the dormouse among other living rodent families. The word "squirrel", first attested in 1327, comes from the Anglo-Norman esquirel, from the Old French escurel, the reflex of a Latin word sciurus; this Latin word was borrowed from the Ancient Greek word σκίουρος, which means shadow-tailed, referring to the bushy appendage possessed by many of its members. The native Old English word for the squirrel, ācweorna, survived only into Middle English before being replaced; the Old English word is of Common Germanic origin, cognates of which are still used in other Germanic languages, including the German Eichhörnchen, the Norwegian ikorn/ekorn, the Dutch eekhoorn, the Swedish ekorre and the Danish egern.
Squirrels are small animals, ranging in size from the African pygmy squirrel at 7–10 cm in length and just 10 g in weight, to the Laotian giant flying squirrel at 1.08 m in length and the Alpine marmot, which weighs from 5 to 8 kg. Squirrels have slender bodies with bushy tails and large eyes. In general, their fur is silky, though much thicker in some species than others; the coat color of squirrels is variable between—and even within—species. In most squirrel species, the hind limbs are longer than the fore limbs, while all species have either four or five toes on each paw; the paws, which include an poorly developed thumb, have soft pads on the undersides and versatile, sturdy claws for grasping and climbing. Tree squirrels, unlike most mammals, can descend a tree head-first, they do so by rotating their ankles 180 degrees, enabling the hind paws to point backward and thus grip the tree bark from the opposite direction. Squirrels live in every habitat, from tropical rainforest to semiarid desert, avoiding only the high polar regions and the driest of deserts.
They are predominantly herbivorous, subsisting on seeds and nuts, but many will eat insects and small vertebrates. As their large eyes indicate, squirrels have an excellent sense of vision, important for the tree-dwelling species. Many have a good sense of touch, with vibrissae on their limbs as well as their heads; the teeth of sciurids follow the typical rodent pattern, with large incisors that grow throughout life, cheek teeth that are set back behind a wide gap, or diastema. The typical dental formula for sciurids is 184.108.40.206.0.1.3. Many juvenile squirrels die in the first year of life. Adult squirrels can have a lifespan of 5 to 10 years in the wild; some can survive 10 to 20 years in captivity. Premature death may be caused when a nest falls from the tree, in which case the mother may abandon her young if their body temperature is not correct. Many such baby squirrels have been rescued and fostered by a professional wildlife rehabilitator until they could be safely returned to the wild, although the density of squirrel populations in many places and the constant care required by premature squirrels means that few rehabilitators are willing to spend their time doing this and such animals are euthanized instead.
Squirrels mate either once or twice a year and, following a gestation period of three to six weeks, give birth to a number of offspring that varies by species. The young are altricial, being born naked and blind. In most species of squirrel, the female alone looks after the young, which are weaned at six to ten weeks and become sexually mature by the end of their first year. In general, the ground-dwelling squirrel species are social living in well-developed colonies, while the tree-dwelling species are more solitary. Ground squirrels and tree squirrels are either diurnal or crepuscular, while the flying squirrels tend to be nocturnal—except for lactating flying squirrels and their young, which have a period of diurnality during the summer; because squirrels cannot digest cellulose, they must rely on foods rich in protein and fats. In temperate regions, early spring is the hardest time of year for squirrels because the nuts they buried are beginning to sprout, while many of the usual food sources have not yet become available.
During these times, squirrels rely on the buds of trees. Squirrels, being herbivores, eat a wide variety of plants, as well as nuts, conifer cones, fruits and green vegetation; some squirrels, however consume meat when faced with hunger. Squirrels have been known to eat small birds, young snakes, smaller rodents, as well as bird eggs and insects. Indeed, some tropical squirrel species have shifted entirely to a diet of insects. Predatory behavior has been observed in various species of ground squirrels, in particular the thirteen-lined ground squirrel. For example, Bailey, a scientist in the 1920s, observed a thirteen-lined ground squirrel preying upon a young chicken. Wistrand reported seeing this same species eating a freshly killed snake. Whitaker examined the stomachs of 139 thirteen-lined ground squirrels and found bird flesh in four of the specimens and the remains of a short-tailed shrew in one.
Flight interception trap
A flight interception trap is a used trapping system for flying insects. It is well-suited for collecting beetles, since these animals drop themselves after flying into an object, rather than flying upward. Flight Interception Traps are used to collect flying species which are not to be attracted to bait or light; the basis of any Flight Interception Trap consists of an upright placed see-through barrier under which one or more small basins are placed. The barrier may consist of such materials as plastic mesh, a transparent plastic sheet or Plexiglas, although the latter does not work well for day-active insects since it is visible to them due to its specific refraction; the basins are filled with a preserving fluid such as ethanol, propylene glycol, salt-saturated water or plain water. The best preservative to keep internal organs in good condition is FAACC, a solution of formaldehyde. A small amount of detergent is added causing the insects to sink. Yellow pans with soapy water may be used alone.
The water itself can be an attractant in dry environments. Depending on either the desired information or desired species the construction can be put in open land or in the forest, it is important to place the barrier in a straight angle with the most flying route for insects, such as to maximize results. The basins can be checked daily, weekly or less often. Maximum time between two checks depends on the used preservatives, since not all preservatives are suited for preserving insects for a longer time. To prevent the basins from filling up with litter, most researchers place some kind of roof over the trap; this keeps leaves from falling in while it keeps the rain out
A fish trap is a trap used for fishing. Fish traps can have the form of a lobster trap; some fishing nets are called fish traps, for example fyke nets. A typical contemporary trap consists of a frame of thick steel wire in the shape of a heart, with chicken wire stretched around it; the mesh wraps around the frame and tapers into the inside of the trap. When a fish swims inside through this opening, it cannot get out, as the chicken wire opening bends back into its original narrowness. Contemporary eel traps are constructed of many materials. In earlier times, traps were constructed of fibre. Traps are culturally universal and seem to have been independently invented many times. There are two types of trap, a permanent or semi-permanent structure placed in a river or tidal area and bottle or pot trap that are but not always baited to attract prey, are periodically lifted out of the water; the Mediterranean Sea, with an area of about of 2.5 million km2, is shaped according to the principle of a bottle trap.
It is easy for fish from the Atlantic Ocean to swim into the Mediterranean through the narrow neck at Gibraltar, difficult for them to find their way out. It has been described as "the largest fish trap in the world"; the prehistoric Yaghan people who inhabited the Tierra Del Fuego area constructed stonework in shallow inlets that would confine fish at low tide levels. Some of this extant stonework survives at Bahia Wulaia at the Bahia Wulaia Dome Middens archaeological site. In southern Italy, during the 17th century, a new fishing technique began to be used; the trabucco is an old fishing machine typical of the coast of Gargano protected as historical monuments by the homonym National Park. This giant trap, built in structural wood, is spread along the coast of southern Adriatic in the province of Foggia, in some areas of the Abruzzese coastlines and in some parts of the coast of southern Tyrrhenian Sea. Indigenous Australians were, prior to European colonisation, most populous in Australia's better-watered areas such as the Murray-Darling river system of the south-east.
Here, where water levels fluctuate seasonally, indigenous people constructed ingenious stone fish traps. Most have been or destroyed; the largest and best-known are those on the Barwon River at Brewarrina, New South Wales, which are at least preserved. The Brewarrina fish traps caught huge numbers of migratory native fish as the Barwon River rose in flood and fell. In southern Victoria, indigenous people created an elaborate system of canals, some more than 2 km long; the purpose of these canals was to catch eels, a fish of short coastal rivers. The eels were caught by a variety of traps including stone walls constructed across canals with a net placed across an opening in the wall. Traps at different levels in the marsh came into operation as the water level fell. Somewhat similar stone-wall traps were constructed by Native American Pit River people in north-eastern California. A technique called; this involves the construction of a temporary dam resulting in a drop in the water levels downstream— allowing fish to be collected.
Used in Chile in Chiloé, which were unusually abundant. The manner in which fish traps are used depends on local conditions and the behaviour of the local fish. For example, a fish trap might be placed in shallow water near rocks. If placed traps can be effective, it is not necessary to check the trap daily, since the fish remain alive inside the trap unhurt. Because of this, the trap allows for the release of undersized fish as per fishing regulations. Animal trapping Fishing net Slack-Smith RJ Fishing with Traps and Pots Volume 26 of FAO training series, FAO, Rome. ISBN 9789251043073. Alvarez, R. Munita, M. Fredes, J. y Mera, R. Corrales de pesca en Chiloé. Imprenta América. Media related to Fish traps at Wikimedia Commons Media related to Bottle traps at Wikimedia Commons Corral de pesca Fish traps
A Timms trap is a device used to capture and kill common brushtail possums. Their use is commonplace in New Zealand. In Australia, where the possum is a protected native species, the Timms trap is illegal, despite the high population there; the trap uses a spring-loaded metal mouth to break the neck of the animal, resulting in a rapid and humane death. It requires baiting with fresh fruit in order to attract a pest, which inserts its head through the hole at the front, springing the trap. A Timms trap, as a form of kill trap, is inexpensive, simple to use, provides an effective means of pest control for gardens and similar-sized areas; the use of fruit as bait reduces the likelihood. Timms traps for possum control, Auckland Regional Council Possums, New Zealand Government Web Site
Animal trapping, or trapping, is the use of a device to remotely catch an animal. Animals may be trapped for a variety of purposes, including food, the fur trade, pest control, wildlife management. Neolithic hunters, including the members of the Cucuteni-Trypillian culture of Romania and Ukraine, used traps to capture their prey. An early mention in written form is a passage from the self-titled book by Taoist philosopher Zhuangzi describes Chinese methods used for trapping animals during the 4th century BC; the Zhuangzi reads, "The sleek-furred fox and the elegantly spotted leopard...can't seem to escape the disaster of nets and traps.” "Modern" steel jaw-traps were first described in western sources as early as the late 16th century. The first mention comes from Leonard Mascall's book on animal trapping, it reads, "a griping trappe made all of yrne, the lowest barre, the ring or hoope with two clickets." The mousetrap, with a strong spring device spring mounted on a wooden base, was first patented by William C. Hooker of Abingdon, Illinois, in 1894.
Native Americans trapped fur bearing animals with pits, dead falls, snares. Trapping was widespread in the early days of North American settlements, companies such as the Canadian fur brigade were established. In the 18th century blacksmiths manually built leghold traps, by the mid-19th century trap companies manufacturing traps and fur stretchers, became established; the monarchs and trading companies of Europe invested in voyages of exploration. The race was on to establish trading posts with the natives of North America, as trading posts could function as forts and legitimize territorial claims; the Hudson's Bay Company was one such business. They traded commodities such as rifles, knives, frying pans and blankets for furs from trappers and Native Americans. Trappers and mountain men were the first European men to cross the Great Plains to the Rocky Mountains in search of fur, they traded with Native Americans from whom they learned trapping skills. Beaver was one of the main animals of interest to the trappers as the fur wore well in coats and hats.
Beaver hats became popular in the early 19th century but the fashion changed. Towards the end of the century beaver became locally extinct in others; the decline in key species of fur-bearers, due to over-harvesting, the emergence of the first regulatory laws marked the end of the heyday of unregulated trapping. Many trappers turned to buffalo hunting, serving as scouts for the army or leading wagon trains to the American west; the trails that trappers used to get through the mountains were used by settlers heading west. Trapping is carried out for a variety of reasons, it was for food and other animal products. Trapping has since been expanded to encompass "pest control", wildlife management, the pet trade, zoological specimens. In the early days of the colonization settlement of North America, the trading of furs was common between the Dutch and Native Americans, the French and Native Americans or English and the local Native Americans. Many locations where trading took place were referred to as trading posts.
Much trading occurred along the Hudson River area in the early 1600s. In some locations in the US and in many parts of southern and western Europe, trapping generates much controversy as it is seen as a contributing factor to declining populations in some species. One such example is the Canadian Lynx. In the 1970s and 1980s, the threat to lynx from trapping reached a new height when the price for hides rose to as much as $600 each. By the early 1990s, the Canada lynx was a clear candidate for Endangered Species Act protection. In response to the lynx’s plight, more than a dozen environmental groups petitioned FWS in 1991 to list lynx in the lower 48 states. Fish and Wildlife Services (FW regional offices and field biologists supported the petition, but FWS officials in the Washington, D. C. headquarters turned it down. In March 2000, the FWS listed the lynx as threatened in the lower 48. In recent years, the prices of fur pelts have declined so low, that some trappers are considering not to trap as the cost of trapping exceeds the return on the furs sold at the end of the season.
Beaver castors are used in many perfumes as a sticky substance. Trappers are paid by the government of Ontario to harvest the castor sacs of beavers and are paid from 10–40 dollars per dry pound when sold to the Northern Ontario Fur Trappers Association. In the early 1900s, muskrat glands were used in making perfume or women just crush the glands and rub them on their body. Trapping is used for pest control of beaver, raccoon, bobcat, Virginia opossum, squirrel, rat and mole in order to limit damage to households, food supplies, farming and property. Traps are used as a method of pest control as an alternative to pesticides. Spring traps which holds the animal are used — mousetraps for mice, or the larger rat traps for larger rodents like rats and squirrel. Specific traps are designed for inverterbrates such as spiders; some mousetraps can double as an insect or universal trap, like the glue traps which catch any small animal that walks upon them. Though it is common to state that trapping is an effective means of pest control, a counter-example is found in the work of Dr. Jon Way, a biologist in Massachusetts.
Dr Way reported that the death or disappearance of a territorial male coyote can lead to double litters, postulates a possible resultant increase in coyote density. Coexistence programs that take this scientific research into account are being pursued by groups such as the Association for the Protection of Fur-Bearing Animal
Artificial shelter for spiders
Artificial shelters known as artificial cover objects, are a type of trap, used to capture spiders. Artificial shelters are designed to be a place; these traps can be used in research to record the presence or absence of a spider, the approximate age and the species of the spider. This type of trap is considered suitable for the insect hobbyist. Artificial shelters made to capture arachnids can be made out of nearly any construction material at hand; some of the more common materials are plastic. However, other materials like cardboard or bubble wrap have been used. Arachnid traps can vary in their design as well. However, the basic principle remains: these traps are meant for the animal to seek shelter inside. To properly attract spiders, one must make the area of the trap dark, to make it a desirable place for the target to build a web; this can be done either by covering the surface that lets in light with black plastic and/or positioning the trap in a way that light doesn't hit it. Artificial shelters can be made out of many different materials, though some of the more common ones are listed below.
Untreated pine wood Transparent acetate or acrylic for a “viewing window” stapled over the wood shelter. Black polythene to block light from entering the shelter. Plastic coated wire for tree attachment Corrugated cardboard Bubble wrap Twine or tape, used to secure trap to tree Most of the advantages and disadvantages depend on the materials used in constructing the trap. For example, using cardboard may be inexpensive, easy to assemble, economically advantageous to create many at once, but will deteriorate with any precipitation. Conversely, an artificial cover object made of untreated pine wood may be more expensive and require specialty skills and equipment to build, but is sturdy and long lasting; the placement of these traps is dependent on which type of spiders are desired. The time of the year these traps are set will influence the species and maturity of caught spiders. For grass spiders, mature adults can best be caught in early fall. Placement of traps for this species would be most effective in a grass-like habitat on the ground.
For best results, these traps should be left undisturbed for a length of time. This time span can range from a couple weeks to a month or more; the time given for collection varies, but there is a higher rate of capture the longer the trap is set. Collection of spiders from artificial cover traps is possible but methods vary with the design of the trap. Collection involves removing the spider from the trap and placing them into containers for long term preservation. Glass jars are most used for this since they are transparent and do not deteriorate in reaction to the chemicals used for preserving specimens. For long and narrow traps, tipping the opening into the collection jar and tapping it until the spider falls out is effective. However, it is sometimes necessary to use a thin object to dislodge the spider. For traps such as the artificial cover object, placing the collection jar just beneath the spider and using a probe to push it into the jar seems to be an effective method. After the spider has been caught, one prepares it for long term preservation.
Ethanol mixed with water has been considered the best by many for preserving arachnids. However, pure ethanol is rare and expensive, so isopropyl alcohol is used instead; this preservative does not harden the spiders as much as ethanol. When using isopropyl alcohol, a 70-80% concentration solution is most effective and can be purchased at any convenience store. Spider Insect trap Malaise trap Pitfall trap Pheromone trap Insect collecting Preserving Insects and Related Arthropods