THE NORTHERN LEOPARD FROG

 

Lithobates pipiens^[1][3][4][5] formerly Rana pipiens,^[6][7] commonly known as the northern leopard frog, is a species of leopard frog from the true frog family, native to parts of Canada and the United States. It is the state amphibian of Minnesota and Vermont. 

 

The northern leopard frog is a fairly large species of frog, reaching about 11 cm (4.3 in) in snout-to-vent length. It varies from green to brown in dorsal color, with large, dark, circular spots on its back, sides, and legs.^[8] Each spot is normally bordered by a lighter ring. A pair of dorsolateral folds starting from the back of the eye runs parallel to each other down the back. These dorsolateral folds are often lighter or occasionally pinkish in colour. Also, a pale stripe runs from the nostril, under the eye and tympanum, terminating at the shoulder. The ventral surface is white or pale green. The iris is golden and toes are webbed.Tadpoles are dark brown or grey, with light blotches on the underside. The tail is pale tan.

Brown morph northern leopard frog in a wood chip pile in Iowa

The northern leopard frog has several different color variations, with the most common two being the green and the brown morphs, with another morph known as the burnsi morph. Individuals with the burnsi 

Near Welland Canal, Ontario

Northern leopard frogs have a wide range of habitats. They are found in permanent ponds, swamps, marshes, and slow-moving streams throughout forest, open, and urban areas.^[11] They normally inhabit water bodies with abundant aquatic vegetation. In the summer, they often abandon ponds and move to grassy areas and lawns. They are well adapted to cold and can be found above 3,000 m (9,800 ft) above mean sea level. Males make a short, snore-like call from water during spring and summer. The northern leopard frog breeds in the spring (March–June). Up to 6500 eggs are laid in water, and tadpoles complete development within the breeding pond. Tadpoles are light brown with black spots, and development takes 70–110 days, depending on conditions. Metamorph frogs are 2–3 cm (0.79–1.18 in) long and resemble the adult.

 

 This species was once quite common through parts of western Canada and the United States until declines started occurring during the 1970s. Although the definitive cause of this decline is unknown, habitat loss and fragmentation, environmental contaminants, introduced fish, drought, and disease have been proposed as mechanisms of decline and are likely preventing species' recovery in many areas.^[8] Many populations of northern leopard frogs have not yet recovered from these declines.

 

 Northern leopard frogs are preyed upon by many different animals, such as snakes, raccoons, other frogs, and even humans. They do not produce distasteful skin secretions and rely on speed to evade predation.

They eat a wide variety of animals, including crickets, flies, worms, and smaller frogs. Using their large mouths, they can even swallow birds and garter snakes. In one case, a bat was recorded as prey of this frog.^[12] This species is similar to the pickerel frog (Lithobates palustris) and the southern leopard frog (Lithobates sphenocephalus).

The northern leopard frog produces specific ribonucleases to its oocytes. Those enzymes are potential drugs for cancer. One such molecule, called ranpirnase (onconase), is in clinical trials as a treatment for pleural mesothelioma and lung tumors. Another, amphinase, has been described as a potential treatment for brain tumors.^[13]

The northern leopard frog has been a preferred species for making discoveries about basic properties of neurons since the 1950s. The neuromuscular junction of the sciatic nerve fibers of the sartorius muscle of this frog has been the source of initial data about the nervous system.^{[14][15][16][17][18][19][20]}

The northern leopard frog is a popular species for in vitro experiments in muscle physiology and biomechanics due to the ease of accessibility for investigators in its native range and the ability of the sartorius muscle to stay alive in vitro for several hours. Furthermore, the reliance of the frog on two major modes of locomotion (jumping and swimming) allows for understanding how muscle properties contribute to organismal performance in each of these modes.

Northern leopard frogs occur from Great Slave Lake and Hudson Bay, Canada, south to Kentucky and New Mexico, USA.^[21][22] It is also found in Panama, where it is endemic to the central cordillera and western Pacific lowlands, although this is most likely an undescribed species.^[1] They occupy grasslands, lakeshores, and marshes. 

 

 

 

 

 

 

 Range of L. pipiens

 

 

 

 

 

 

 

 

THE BLACK- NECKED CRANE

 

The Black-necked Crane (Grus nigricollis) is a medium-sized crane in Asia that breeds on the Tibetan Plateau and remote parts of India and Bhutan. It is 139 cm (55 in) long with a 235 cm (7.8 ft) wingspan, and it weighs 5.5 kg (12 lbs). It is whitish-gray, with a black head, red crown patch, black upper neck and legs, and white patch to the rear of the eye. It has black primaries and secondaries. Both sexes are similar. Some populations are known to make seasonal movements. It is revered in Buddhist traditions and culturally protected across much of its range. A festival in Bhutan celebrates the bird while the Indian union territory of Jammu and Kashmir considers it as the state bird.

 At Bronx Zoo, New York, USA.

 

Description

 

 

This medium-sized crane is mostly grey with a black head and neck. The lores and crown are naked and dull red. A small patch of white feathers are present below and behind the eye. The tail is black and makes it easy to distinguish at a distance from the similar looking common crane which has grey tail.^[2]

 

From Phobjikha Valley, Bhutan.

The black-necked crane summers mainly in the high altitude Tibetan Plateau. The breeding areas are alpine meadows, lakeside and riverine marshes and river valleys. They also make use of barley and wheat fields in these areas. Wintering areas tend to be in sheltered valleys or lower altitudes. The largest populations are in China with smaller numbers extending into Vietnam, Bhutan and India.^[3] Small populations have been noted in northern Sikkim.^[4] A small group of 20 to 40 was once known to regularly visit the Subansiri area in the Apa Tani valley^[5] until 1975^[6] and vagrants have been recorded in Nepal.^[7]

 

 

In 1996 there were about 4,000 of the birds, most of whom spent their winters in Tibet in the valleys of the Nyanga, Lhasa and Pengbo rivers and the middle reaches of the Yarlung Tsangpo.^[8] The Hutoushan Reservoir in the Pengbo valley is an important winter resting place, with a 96 square kilometres (37 sq mi) Linzhou Black-necked Crane Preservation Zone established in 1993.^[9] Black-necked cranes also winter in small numbers in two valleys of western Arunachal Pradesh, India. These are Sangti and Zemithang.^[10][11][12]

 

Behaviour and ecology

 

Black-necked cranes forage on the ground in small groups, often with one bird acting as a sentinel. In winter, the groups arrive and leave the feeding grounds together, but may split into family groups, each group keeping their own small feeding territories in a big marshes or fields.^[6] They spend nearly 75% of the day foraging with peak feeding in the early morning and late afternoon.^[3] While foraging, they keep walking and they also walk long distances between the feeding spots. In this manner, they cover several kilometers a day while foraging.^[13] They feed on the tubers of sedges, plant roots, earthworms, insects and other invertebrates, frogs and other small vertebrates. They may also feed on fallen grains of barley, oats and buckwheat and will sometimes dig up and feed on potatoes, carrots and turnips.^[3][14] Their loud trumpeting calls are similar to those of other cranes.^[2]

 A 1938 photograph of a flock in the Brahmaputra valley

These birds are very wary, but in some areas they are accustomed to the local people who do not disturb them. These cranes appear to be able to distinguish people in traditional dress and are especially wary of others.^[13]

100 odd of this species come to India every year for breeding. Photograph has been taken at Tso Kar, Ladakh, Jammu and Kashmir, India.

 

 

Like many other crane species, they are believed to form long-lasting pair bonds and dancing displays are made during the breeding season. The breeding birds are territorial and will chase away any intruders of the same species immediately, though they are generally tolerant of other species.^[13] The nest site is usually a pre-existing mud island inside a large shallow wetland, sometimes shared along with bar-headed goose. The nest varies from a scantily lined scratch in the ground to a structure made of grass, rushes and weeds with a depression in the centre, sometimes the eggs laid directly on the grass without any structure.^[15][16] Eggs are laid mainly in May and June. One or two eggs.^[2][17] The birds are relatively more wary when the young ones are small. Till the time when the young ones are able to fly, the family kept moving around the nesting location, but later the family started traveling far and wide in the course of a day. Though the young ones are able to forage independently, usually they accompany the parents during foraging. Short, subdued nasal "kurrr" calls are used by the family to keep in contact and also by adults to indicate availability of food to juveniles. The adults were found to feed the young ones mainly with fish in Ladakh, adults fishing like herons.^[13] They are endangered because of the hunters.

 

A couple of black-necked Tibetan cranes spotted in 2013 near Yamdrok Lake, Tibet Autonomous Region

 

 

 

The estimated population of the black-necked crane is between 8800 and 11000 individuals. These birds are legally protected in China, India and Bhutan. However habitat modification, drying of lakes and agriculture are threats to the populations. In many areas, dogs belonging to herders are a major threat to young birds. An incident of leopards preying on the roosting cranes during the night has been recorded from the Phobjika valley of Bhutan.^[18] In Bhutan, collisions with power lines have been another cause of mortality in some areas.^[1][19] Eggs may also be preyed on by ravens that may use the opportunity 

 

 

provided when humans disturb the parents.^[3] The drying of wetlands can cause increased accessibility of the nests leading to predation while a rise in the water level can submerge nests.^[20] Loss and degradation of habitat are the main threats facing the black-necked cranes. The problems are most serious in the wintering areas, where wetlands are extensively affected by human activity including irrigation, dam construction, draining, and grazing pressure. In Tibet, widespread changes in traditional agricultural practices have reduced the availability of waste barley and spring wheat.^[20]

Populations in Bhutan are well protected both culturally and legally although some disturbance from tourism exists.^[21]

The black-necked crane is evaluated as Near Threatened on the IUCN Red List of Threatened Species.^[1] It is listed on Appendix I of CITES.

See also

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

THE BRAZILIAN PORCUPINE

 

The Brazilian porcupine (Coendou prehensilis) is a porcupine found in Brazil, Argentina, Uruguay, Colombia, Venezuela, Guyana, French Guiana, Peru, Paraguay, Suriname, Bolivia and Trinidad, with a single record from Ecuador. It inhabits tropical forests at elevations up to 1500 m.^[2]

The body is covered with short, thick spines that are whitish or yellowish in color, mixed with the darker hair, while the underside is grayish. The lips and nose are fleshy. The tail is prehensile, with the tip curling upward so as to get a better grip on tree branches. This porcupine can grow to forty inches long (1 m), but half of that is tail. It weighs about nine pounds (4.1 kg). No spines are found on the tail, which is long (330–485 mm (13.0–19.1 in)). Its feet are reflective of their arboreal lifestyle, well-adapted for gripping branches, with four long-clawed toes on each.

 

This shy, nocturnal porcupine is solitary or lives in pairs in the branches of trees. During the day it rests in a cavity in a hollow tree or in a well-shaded area of the canopy, 6 to 10 meters above the ground. It rarely descends to the ground, but it shows little fear if it happens to be caught. It is not aggressive but will defend itself ferociously if attacked. Its diet consists of leaves, fruit, small fresh twigs and shoots, seeds, roots, flowers, stems, bark and cambium layer of some trees, buds and agricultural crops like corn and bananas.^[3][4] This creature can easily be tamed enough to be kept in captivity. Intra-specific interactions consist of biting and attempts to injure adversaries with their sharp quills. When excited, porcupines stamp their hind feet. Vocalizations consist of growls and cries. If caught, the porcupine rolls into a ball. The prehensile tail is used to curl around branches when climbing.

As a rule the female gives birth to a single young one in the spring. The newborn porcupine is covered with red hairs and small spines, which harden shortly after birth. 

 

 

 

 

 

 

 

 

 

 

 

THE CHINCHILLA

 

 

 Chinchillas are either of two species (Chinchilla chinchilla and Chinchilla lanigera)^[3] of crepuscular rodents of the parvorder Caviomorpha. They are slightly larger and more robust than ground squirrels, and are native to the Andes mountains in South America.^[4] They live in colonies called "herds" at high elevations up to 4,270 m (14,000 ft). Historically, chinchillas lived in an area that included parts of Bolivia, Peru, Argentina, and Chile, but today, colonies in the wild are known only in Chile.^[5] Along with their relatives, viscachas, they make up the family Chinchillidae. They are also related to the chinchilla rat.

The chinchilla has the densest fur of all mammals that live on land. In the water, the sea otter has a denser coat. The chinchilla is named after the Chincha people of the Andes, who once wore its dense, velvet-like fur.^[6] By the end of the 19th century, chinchillas had become quite rare after being hunted for their ultra-soft fur. Most chinchillas currently used by the fur industry for clothing and other accessories are farm-raised.^[7] Domestic chinchillas descended from C. lanigera are sometimes kept as pets, and may be considered a type of pocket pet.

 Chinchilla lanigera at the Wrocław Zoo in Poland

The two living species of chinchilla are Chinchilla chinchilla^[1][2] (formerly known as Chinchilla brevicaudata) and Chinchilla lanigera. C. chinchilla has a shorter tail, a thicker neck and shoulders, and shorter ears than C. lanigera. The former species is currently facing extinction; the latter, though rare, can be found in the wild.^[8] Domesticated chinchillas are thought to be of the C. lanigera species.

Chinchilla habitat in the Andes mountains of Chile

 

 Formerly, chinchillas occupied the coastal regions, hills, and mountains of Chile, Peru, Argentina, and Bolivia. Overexploitation caused the downturn of these populations and, as early as 1914, one scientist claimed that the species was headed for extinction. Five years of fieldwork (published in 2007) in Jujuy Province, Argentina, failed to find a single specimen. Populations in Chile were thought extinct by 1953, but the animal was found to inhabit an area in the Antofagasta Region in the late 1900s and early 2000s. The animal may be extinct in Bolivia and Peru, though one specimen found (in a restaurant in Cerro de Pasco) may hail from a native population.^[5]

 

 In their native habitats, chinchillas live in burrows or crevices in rocks. They are agile jumpers and can jump up to 1.8 m (6 ft). Predators in the wild include birds of prey, skunks, felines, snakes and canines. Chinchillas have a variety of defensive tactics, including spraying urine and releasing fur if bitten. In the wild, chinchillas have been observed eating plant leaves, fruits, seeds, and small insects.^[8]

 In nature, chinchillas live in social groups that resemble colonies, but are properly called herds. Herd sizes can range from 14 members up to 100, this is both for social interaction as well as protection from predators.^[9] They can breed any time of the year. Their gestation period is 111 days, longer than most rodents. Due to this long pregnancy, chinchillas are born fully furred and with eyes open. Litters are usually small in number, predominantly two.^[10]

 Both species of chinchilla are currently listed as Endangered by the IUCN Red List of Threatened Species due to a severe population loss approximated at a 90% global population loss over the last 15 years.^[1] The severe population decline has been caused by chinchilla hunting by humans. The long tailed-species was listed on The IUCN Red List as “Very rare and believed to be decreasing in numbers” in 1965. From 1982 to 1996, both species were listed as Indeterminate. In 2006, the long-tailed species was listed as "Vulnerable" while the short-tailed species was listed as "Critically Endangered". By 2008, both were listed as "Critically Endangered", and in 2016 they were reclassified as "Endangered" due to limited recovery in some areas.^[11][12]

 

Fur industry

 

Chinchilla fur trade on an international level goes back to the 16th century. Their fur is popular due to its extremely soft feel, which is caused by the sprouting of 60 hairs (on average) from each hair follicle. The color is usually very even, which makes it ideal for small garments or the lining of larger ones, though some large pieces can be made entirely from the fur. A single, full-length coat made from chinchilla fur may require as many as 150 pelts, as chinchillas are relatively small.^[13] Their use for fur led to the extinction of one species, and put serious pressure on the other two. Though it is illegal to hunt wild chinchillas, they are now on the verge of becoming extinct because of continued poaching. Domesticated chinchillas are still bred for fur.^[14]

 

As pets

 

The domestic chinchilla is descended from Chinchilla lanigera, the long-tailed Chinchilla, and the more common one in the wild after the other species, Chinchilla chinchilla, or short-tailed Chinchilla, has been hunted nearly to extinction. Therefore, domestic chinchillas have thinner bodies, longer tails and larger ears.

Mosaic Chinchilla

Chinchillas are popular pets, though they require extensive exercise and dental care,^[15] due to their teeth continually growing throughout their life span, and since they lack the ability to sweat, they require a temperature-controlled environment.^[16]

 

The animals instinctively clean their fur by taking dust baths, in which they roll around in special dust made of fine pumice, a few times a week; they do not bathe in water. Their thick fur resists parasites, such as fleas, and reduces loose dander.^[17]

 

 

As pets, Chinchilla not only need scrupulous physically care, like temperature control, diet control, but also psychological care, which refers to simply, playing with them.^[18] It is probably^{[clarification needed]} correct to say that the chinchilla is more sensitive psychologically than physically. It can survive an astonishingly bad diet, mistreatment and poor physical environment^{[further explanation needed]} if psychological factors such as those caused by moving the animal from its accustomed quarters or shipping it. Spending a few minutes to give them some touches^{[clarification needed]} or let them out from the cage would satisfy their basic emotional need^{[citation needed]}.

 

Chinchillas have been used in research since the 1950s. Since the 1970s, the prime interest in chinchillas by researchers is their auditory system.^[19] Other research fields in which chinchillas are used as an animal model include the study of Chagas disease, gastrointestinal diseases, pneumonia, and listeriosis, as well as of Yersinia and Pseudomonas infections.^[20]

 

Veterinary medicine

 

Fractures

 

Chinchillas live active lives and can recover well from minor physical injury.^[21] Fractures may be problematic, because chinchillas will want to sit on their hind legs and eat with their front paws, so many types of injuries will disturb their natural eating behavior.^[21]

 

Convulsions

 

Chinchilla breeders sometimes report seeing their animals have convulsions. Typically this happens only irregularly and then only for a few seconds, and not more than a few minutes at the most.^[22] Convulsions are a symptom that can have many causes, including a brain problem such as hemorrhaging, a vitamin or dietary element deficiency in the diet, or some kind of nervous system injury.^[22] If convulsions are observed after chinchillas mate then it is likely related to a circulatory problem.^[22] Some chinchillas who are kept in groups have stress convulsions during feeding if they see other chinchillas getting food first.^[23] Vitamin B, cardiac medication, or a calcium injection may be used to prevent convulsions.^[22]

 

Infectious diseases

A standard domestic chinchilla

Listeriosis is not a typical chinchilla disease, but in group housing conditions it can spread as a digestive tract disease in a community.^[24] Pasteurella can be contracted from food and then transmitted among a group of chinchillas.^[25] Symptoms include apathy, digestive disorder, and fever.^[26] Pseudomonas aeruginosa infections are widely distributed in nature and can affect chinchillas like many other animals.^[27] They can cause wide deaths in populations of chinchillas and spontaneous abortion in pregnant chinchillas.^[27]

 

 

Respiratory tract infections can be caused by many pathogens, but, regardless of cause, usually result in difficult breathing and a nasal discharge.^[28] Young chinchilla are more likely to be affected and these infections are unlikely to result in an epidemic, even if transmissible.^[28]

 

 

Gastrointestinal disorders are observed as either constipation or diarrhea.^[28] These are almost always the result of a problem with the diet, but if the diet is optimal, they could be the symptom of an infectious disease.^[29] Constipation in chinchillas is difficult to observe in groups because it may not be obvious than an animal is not contributing to the population's waste.^[29] If it is identified, mild treatments include feeding paraffin to soften the feces.^[29]

 

 

Chinchillas are easily distressed, and when they are unhappy, they may exhibit physical symptoms.^[30] A common indicator of stress in pet chinchillas is fur-chewing (or fur barbering), an excessive grooming behavior that results in uneven patches of fur; chinchillas may chew their own fur or that of their cagemates.^[31] Fur-chewing can sometimes be alleviated through changes in living environment, but is regarded by some experts to be passed genetically from parents to offspring.^[32] Usually, fur-chewing itself is a benign symptom that does not cause physiological distress.^[33]

 

 

Sick chinchillas may stop eating if they are stressed, which can make them even more weak.^[34] Chinchillas that live in communities are especially sensitive in their breeding seasons of February to March and August to September.^[34] Chinchillas are social animals and are likely to be upset to have their breeding mate changed in breeding season.^[34] They are known to be disturbed by a change of diet in these times.^[34]

 

Pharmaceutical treatment

 

Chinchillas may be treated with chloramphenicol, neomycin, or spectinomycin for digestive problems.^[34] Sulfonamides dissolved in drinking water may be used.^[35] Colistin can be an effective antibiotic.^[35]

 

 

 

 

 

 

 

 

 Range of C. lanigera and C. chinchilla. 

 

  C. chinchilla

  C. lanigera