Animal facts for kids

The stark image of a solitary coyote is familiar to many, thanks to its use in countless Westerns. It has been a persistent image, and for long the coyote was considered to be a solitary animal. But recent studies have shown that in some situations coyotes live cooperatively in a way similar to wolves.

The coyote-whose name derives from the original Aztec word for the species, coyote-is a medium-sized canid with a rather narrow muzzle, large pointed ears and long slender legs. Size varies between populations and from one locale to another, and adult males are usually heavier and larger than adult females.

While the geographic ranges of most predators are shrinking, that of the coyote is increasing. A northerly and, particularly, an easterly expansion from the central Great Plains began in the late 19th century, as local populations of the larger canids, the Gray wolf (Canis lupus) and the Red wolf (C.rufus), were decimated by man.

Coyotes can interbreed with the Domestic dog, the Red wolf and, probably, the Gray wolf (the so-called Eastern coyotes are now thought to be fertile coyote-Gray wolf hybrids). The coyote-Domestic dog hybrid (“coydog”) can reproduce at one year old and has two litters a year. Coydogs are even more liable to attack farm and domestic animals than are coyotes.

Like jackals and wolves, the coyote is an opportunistic predator. Mammals, including carrion, generally make up over 90 percent of its diet. Ground squirrels, rabbits and mice predominate, but larger animals such as the Pronghorn antelope, deer and Rocky mountain sheep are included. Coyotes also eat fruit and insects. Small prey are hunted singly, but larger animals are hunted cooperatively. Coyotes normally stalk small prey from a few meters, but occasionally from as far as 50 meters (165 ft) and for as long as 15 minutes. Two or more coyotes may chase larger prey for up to 400m (1,300ft).

Both sexes attain sexual maturity during the first breeding season (January to March) following birth. Females produce one litter a year, averaging six pups per litter. The young are born blind and helpless in a den and are nursed for a period Of 5-7 weeks. At three weeks pups begin to eat semisolid food regurgitated by both parents and other pack members of both sexes. Most young disperse in their first year and may travel up to 160 km (100mi) before settling down.

The basic social unit in most coyote populations is the breeding pair; and the size of the home range varies from 14 to 65 sqkm (5.5 to 25 sq mi) for males, with an average Of 25 sqkm (9.9 sqmi) for females. Coyotes are now known to form packs similar to wolf-packs, in certain situations. Such packs are formed by delayed dispersal of the young, who remain as “helpers” in a pack; a typical pack consists of about six closely related adults, yearlings and young. It is usually the dominant male and female that breed.

Pack members sleep, travel and hunt larger prey together and cooperate in territorial disputes and defense of carrion. In general, coyote packs are smaller than wolf packs and associations between individuals less stable. The reasons for this may be the early expression of aggression, which is found in coyotes but not in wolves, and the fact that coyotes often mature in their first year whereas wolves do so in their second.

Variation in social organization enables the coyote to thrive on diverse prey and this flexibility is probably the reason for the wide, and expanding, geographic range of the species. Coyotes living in packs are more effective predators of large animals, and where such prey (eg deer, elk) is available, packs Of 3-8 coyotes are found. Where the principal prey is small mammals, the pups disperse early, packs are not formed, and most sightings are of solitary coyotes. Seasonal variation in social structure also occurs: when Ground squirrels and the young of large mammals are available as prey, coyotes spend less time together.

Coyotes use urine marking and calls to define their territory, to communicate with each other, and to strengthen social bonds. The coyote’s howl is unique and consists of a series of high-pitched staccato yelps followed by a prolonged siren wail. Their vocalizations also include barks, barkhowls, group yip-howls and group howls.

During the last 150 years, coyotes have been responsible for large economic losses to US agriculture, especially sheep farming. Some ranchers have lost up to 67 percent of their lambs and 20 percent of their sheep to coyotes in a single year; others lose very few. In fact, there is evidence that attempts to control coyotes by poisoning may also deplete the numbers of their natural prey and lead to increasing attacks by coyotes on farm animals. Although the species is not endangered, it is now totally protected in I2 states and the coyote harvest is regulated by a hunting or trapping season in most of the remaining states and Canada.

The jackal has a bad name: the word can also mean “one who performs menial tasks for others, especially of a base nature.” But the facts about jackals are rather more edifying than the popular image of a cowardly scavenger. Jackals are much less dependent on carrion than is commonly supposed, and their family life is noted for its stability: partnerships between male and female are unusually durable for a mammal.

Jackals are small slender dog-like omnivores with long sharp canines and well developed carnassial teeth used for shearing tough skin. Like most other canids, jackals are lithe muscular runners with long legs and bushy tails. They have large erect ears and an elaborate repertoire of ear, muzzle and tail postures. The average weight of 11kg (241b) applies to all species except the South African Silverbacked jackal, where in some populations the male is usually 1kg (2.2lb) heavier than the female.

Of the four species, the Golden jackal has the widest distribution (East Africa to Burma); the others are limited to Africa. In East Africa, distribution of Golden, Silverbacked and Sidestriped jackals overlaps: but each species occupies a different habitat.

Skeletal remains of Silverbacked jackals 1.7 million years old found in Olduvai Gorge provide the earliest fossil record of a present-day Canis; the species still lives in the brush woodland nearby the gorge.

Coat color and markings also distinguish the species, the coat of the Simien jackal being the most colorful. In the Golden jackal, coat color varies with season and region: on the Serengeti Plain in north Tanzania it is brown-tipped yellow in the rainy season, changing to pale gold in the dry season.

Jackals are opportunistic foragers for their very varied diet. They eat fruits, invertebrates, reptiles, amphibia, birds, small mammals from rodents to Thomson’s gazelles and carrion. In the Silverbacked jackal’s diet, rodents and fruit are the most important items, and the fruit of the tree Balanites aegyptiaca which is highly nutritious and often favored, may even function as a natural “wormer” to alleviate infestation by parasites. In the Serengeti, scavenging usually contributes less than 6 percent of a jackal’s diet.

Cooperative hunting is important for Golden and Silverbacked jackals. In both species, pairs have been observed to be three times more successful than individuals in hunting Thomson’s gazelle fawns. Members of the same family will also cooperate in sharing larger food items, ranging in size from hares to perhaps a wildebeest carcass, and will transport food in their stomachs for later regurgitation to pups or a lactating mother. Food is also cached.

Both sexes mature at 11 months, although they may not breed at once. Some yearlings stay on as “helpers” to assist their parents in raising the next litter. Serengeti Golden jackals court at the end of the dry season (October) and produce pups in the rainy season (December-January). Thus whelping occurs during the period of greatest food abundance on the shortgrass plains.

Silverbacked jackals whelp in July-October, which coincides with a peak in rodent numbers and with fruiting of the balanites tree. Most jackal species have a maximum litter size of nine, but a pregnant Sidestriped jackal has been found with 12 fetuses, so reabsorption of fetuses, or other early mortality, may occur. The number of pups which reach maturity varies; in Serengeti Silverbacked jackal litters without a helper, only one pup survives on average; with one helper, three or more may live.

Evidence of helping behavior has merged in all members of the dog family that have been studied in detail. The jackal helper is fully mature (jackals reach sexual maturity at 11 months), and while subordinate to its parents, is an important member of the family.

Young jackal pups remain in the den-a natural shelter or simple excavation for some three weeks, during which time the mother spends about 90 percent of her time with them, perhaps to keep them warm. She nurses the pups until they are about eight weeks old. The female initiates all den changes, which may be as frequent as every two weeks. When Silverbacked jackal pups are three months old they stop using a den. Pups are fed regularly by regurgitation until about five months old, and may occasionally be fed until they leave their parents, at one or two years of age.

Jackal pairs hold territories Of 0.5-2.5sq km (o.2-1sq mi) throughout the year. They forage and rest together and all their behavior is highly synchronized. They tend to scent mark their territory in tandem, with either male or female making the first mark, probably advertising to intruders that both members of the pair are in residence. The males are strictly monogamous, perhaps because divided paternal care might reduce the number of cubs that survive. Females reserve their aggression for female intruders, thus preventing the sharing of the male and his paternal investment.

Since females may be able to produce litters with several sires, the male needs to ensure that he alone copulates with his mate, if a wasted investment in pups that he has not sired is to be avoided. It is not surprising therefore that the male of a pair fiercely threatens and attacks any male intruder on the territory. Both members of a pair have important roles in maintaining their territory and in raising the young. When one parent dies, the rest of the family is unlikely to survive.

In addition to posture and scent, each jackal species communicates through its own repertoire of calls. These may include howls, yelps, barks and other vocalizations. Silverbacked and Golden are more vocal than Sidestriped jackals. In the Serengeti Goldens locate each other by howling, while the contact call of the Silverbacked jackal is a series of yelps.

In agricultural areas jackals tend to be persecuted by man; and jackals are also killed for their fur. In Ethiopia the Simien jackal’s numbers have been so reduced that this is now an endangered species, with only an estimated 5oo left in the wild.

This non-sporting breed was the first purebred dog developed in America, originated by crossing an English bulldog with an English terrier. Developed in 1869, the breed was first recognized by the American Kennel Club as a distinct breed in 1893. All pure Boston Terriers today are descended from a dog owned about 1884 by a native of Boston.

The Boston Terrier is a small dog, weighing about 7 to 11 kg (about 15 to 25 lb). It has a square, flat skull; large, round, dark eyes that are alert and intelligent; a smooth coat, usually brindle in color with white markings, or black with white markings; a short, square muzzle; small, thin ears; a wide chest; and a short, tapering tail.

Due to its Massachusetts origins, the Massachusetts legislature designated the Boston Terrier as the official state dog in 1979.