The bluefish (Pomatomus saltatrix) is the only extant species of the family Pomatomidae. It is a marine pelagic fish found around the world in temperate and subtropical waters, except for the northern Pacific Ocean.  Bluefish are known as tailor in Australia and New Zealand, elf and shad in South Africa.  It is a popular gamefish and food fish.
The bluefish is a moderately proportioned fish, with a broad, forked tail. The spiny first dorsal fin is normally folded back in a groove, as are its pectoral fins. Coloration is a grayish blue-green dorsally, fading to white on the lower sides and belly. Its single row of teeth in each jaw is uniform in size, knife-edged, and sharp. Bluefish commonly range in size from seven-inch (18-cm) "snappers" to much larger, sometimes weighing as much as 40 lb (18 kg), though fish heavier than 20 lb (9 kg) are exceptional.


Adult bluefish are typically between 20 and 60 cm (8 in. to 2 ft.) long, with a maximum reported size of 120 cm (4 ft.) and 14 kg (31 lb). They reproduce during spring and summer, and can live up to 9 years. Bluefish fry are zooplankton, and are largely at the mercy of currents. Spent bluefish have been found off east-central Florida, migrating north. As with most marine fish, their spawning habits are not well known. In the western side of the North Atlantic, at least two populations occur, separated by Cape Hatteras in North Carolina. The Gulf Stream can carry fry spawned to the south of Cape Hatteras to the north, and eddies can spin off, carrying them into populations found off the coast of the mid-Atlantic, and the New England states.


The four-striped grass mouse (Rhabdomys pumilio) or four-striped grass rat, is a species of rodent in the family Muridae.
It is found throughout the southern half of Africa up to 2,300 metres (7,500 ft) above sea level, extending as far north as the Democratic Republic of the Congo. Its natural habitats are savannas, shrublands, Mediterranean-type shrubby vegetation, hot deserts, arable land, rural gardens, and urban areas.


Cutthroat trout require cold, clear, well-oxygenated, shallow rivers with gravel bottoms or cold, moderately deep lakes. Healthy stream-side vegetation that reduces siltation is typical of healthy cutthroat trout habitat and beaver ponds may provide refuge during periods of drought and over winter. Most populations stay in fresh water throughout their lives and are known as nonmigratory, stream-resident or riverine populations. The coastal cutthroat trout (O. c. clarkii) is the only cutthroat trout subspecies to coevolve through its entire range with the coastal rainbow trout (O. m. irideus). Portions of the westslope cutthroat trout's (O. c. lewisi) range overlap with the Columbia River redband trout (O. m. gairdneri), but the majority of its native range is in headwater tributary streams above major waterfalls and other barriers to upstream migration. At least three subspecies are confined to isolated basins in the Great Basin and can tolerate saline or alkaline water.
Cutthroat trout are opportunistic feeders. Stream-resident cutthroat trout primarily feed on larval, pupal and adult forms of aquatic insects (typically caddisflies, stoneflies, mayflies and aquatic dipterans), and adult forms of terrestrial insects (typically ants, beetles, grasshoppers and crickets) that fall into the water, fish eggs, small fish, along with crayfish, shrimp and other crustaceans. As they grow the proportion of fish consumed increases in most populations. In saltwater estuaries and along beaches, Coastal cutthroat trout feed on small fish such as sculpins, sand lance, salmon fry and herring. They also consume shrimp, small squid and krill. In fresh water, they consume the same diet as stream resident trout—aquatic insects and crustaceans, amphibians, earthworms, small fish and fish eggs. Within the range of the bull trout (Salvelinus confluentus) the cutthroat trout is a forage fish for the piscivorous bull trout.


The cutthroat trout (Oncorhynchus clarkii) is a fish species of the family Salmonidae native to cold-water tributaries of the Pacific Ocean, Rocky Mountains, and Great Basin in North America. As a member of the genus Oncorhynchus, it is one of the Pacific trout, a group that includes the widely distributed rainbow trout. Cutthroat trout are popular gamefish, especially among anglers who enjoy fly fishing. The common name "cutthroat" refers to the distinctive red coloration on the underside of the lower jaw. The specific name clarkii was given to honor explorer William Clark, coleader of the Lewis and Clark Expedition.
Cutthroat trout usually inhabit and spawn in small to moderately large, clear, well-oxygenated, shallow rivers with gravel bottoms. They reproduce in clear, cold, moderately deep lakes. They are native to the alluvial or freestone streams that are typical tributaries of the rivers of the Pacific Basin, Great Basin and Rocky Mountains. Cutthroat trout spawn in the spring and may inadvertently but naturally hybridize with rainbow trout, producing fertile cutbows. Some populations of the coastal cutthroat trout (O. c. clarkii) are semi-anadromous.
Several subspecies of cutthroat trout are currently listed as threatened in their native ranges due to habitat loss and the introduction of non-native species. Two subspecies, O. c. alvordensis and O. c. macdonaldi, are considered extinct. Cutthroat trout are raised in hatcheries to restore populations in their native range, as well as stock non-native lake environments to support angling. The cutthroat trout type species and several subspecies are the official state fish of seven western U.S. states.


Throughout their native and introduced ranges, cutthroat trout vary widely in size, coloration and habitat selection. Their coloration can range from golden to gray to green on the back. Cutthroat trout can generally be distinguished from rainbow trout by the presence of basibranchial teeth at the base of tongue and a maxillary that extends beyond the posterior edge of the eye. Depending on subspecies, strain and habitat, most have distinctive red, pink, or orange linear marks along the underside of their mandibles in the lower folds of the gill plates. These markings are responsible for the common name "cutthroat", first given to the trout by outdoor writer Charles Hallock in an 1884 article in The American Angler. These markings are not unique to the species. Some coastal rainbow trout (Oncorhynchus mykiss irideus) and Columbia River redband trout (O. m. gairdneri) populations also display reddish or pink throat markings.
At maturity, different populations and subspecies of cutthroat trout can range from 6 to 40 inches (15 to 102 cm) in length, depending on habitat and food availability. Sea-run forms of coastal cutthroat trout average 2 to 5 pounds (0.9 to 2.3 kg). The length and weights of mature inland forms vary widely depending on their particular environment and availability of food. Stream-resident fish are much smaller, 0.4 to 3.2 ounces (11 to 91 g), while lacustrine populations have attained weights ranging from 12 to 17 lb (5.4 to 7.7 kg) in ideal conditions. The largest cutthroat trout subspecies is the Lahontan cutthroat trout (O. c. henshawi). These fish average 8 to 9 in (20 to 23 cm) in small streams and 8 to 22 in (20 to 56 cm) in larger rivers and lakes. In ideal environments, the Lahontan cutthroat trout attains typical weights of 0.25 to 8 lb (0.11 to 3.63 kg). The world record cutthroat trout is a Lahontan at 39 in (99 cm) and 41 lb (19 kg).


Gemsbok live in herds of about 10–40 animals, which consist of a dominant male, a few nondominant males, and females. They are mainly desert-dwelling and do not depend on drinking water to supply their physiological needs. They can reach running speeds of up to 60 km/h (37 mph).


The gemsbok is generally a grazer but changes to browsing during the dry season or when grass is sparse. It may dig up to a meter deep to find roots and tubers, supplementing its water intake by eating wild tsama melons and cucumbers, which can provide all the water required (3 liters per 100 kg bodyweight and day).


In 1969, the New Mexico State Department of Game and Fish decided to introduce gemsbok to the Tularosa Basin, New Mexico, in the United States. Ninety-three were released from 1969 to 1977, with the current population estimated to be around 3,000 individuals. As they are capable of year-round breeding, the transplanted population thrives in the absence of their natural predators, such as the lion (Panthera leo), cheetah (Acinonyx jubatus) and leopard (Panthera pardus). Except for calves, the oryx is too large to be preyed on by the cougar (Puma concolor) and most other major American desert carnivores, since the jaguar (Panthera onca) is extirpated from the state, and the reintroduced Mexican wolf (Canis lupus baileyi) is too low in population numbers (and all known Mexican wolf populations are over 100 miles away). The species is therefore primarily managed by regulated hunting. Gradually expanding their range from Tularosa Basin towards the west and northwest, an unknown number of animals are now also established in the San Andres National Wildlife Refuge, the Jornada Biosphere Reserve as well as the endorheic drainage basins east of Caballo Mountains, especially where these are traversed by the Jornada del Muerto trail north of Upham.


The gemsbok, gemsbuck or South African oryx (Oryx gazella) is a large antelope in the genus Oryx. It is native to the arid regions of Southern Africa, such as the Kalahari Desert. Some authorities formerly included the East African oryx as a subspecies.
The gemsbok is depicted on the coat of arms of Namibia, where the current population of the species is estimated at 373,000 individuals. In the town of Oranjemund, gemsbok wander freely around the streets, taking advantage of the vegetation in the town, such as grass in the parks and the many trees.


The gemsbok is polygynous, with one resident male mating with the receptive females in the herd. The male is known to secure exclusive mating access to the females by attempting to herd mixed or nursery herds onto his territory. The gemsbok has no specified breeding season, but the young in a given herd tend to be of a similar age due to reproductive synchrony between females. Pregnant females leave the herd before giving birth. The gestation period lasts 270 days and mothers give birth to 1-2 offspring. The calf remains hidden 6 weeks after birth, after which mother and calf rejoin the herd. The calf is weaned at 3.5 months, becomes independent at 4.5 month, and achieves sexual maturity at 1.5–2 years in both sexes.


Gemsbok are widely hunted for their spectacular horns that average 85 cm (33 in) in length.  From a distance, the only outward difference between males and females is their horns, and many hunters mistake females for males each year.  In males horns tend to be thicker with larger bases.  Females have slightly longer, thinner horns.
Female gemsbok use their horns to defend themselves and their offspring from predators, while males primarily use their horns to defend their territories from other males.
Gemsbok are one of the few antelope species where female trophies are sometimes more desirable than male ones. A gemsbok horn can be fashioned into a natural trumpet and, according to some authorities, can be used as a shofar.


The blackstripe topminnow is found in Canada along a roughly 60 kilometre stretch of Ontario's Sydenham River. In the United States, it occupies other parts of the southern drainage of lakes Erie and Michigan and also the Mississippi drainage basin between Illinois and the Gulf of Mexico. The entire Canadian population of this small freshwater fish lives along a roughly 60 kilometre stretch of the Sydenham River in southwestern Ontario where its presence was discovered only in 1972, the blackstripe topminnow is a fairly hardy fish although its greatest threats come from changes to its habitat due to human activity.


The blackstripe topminnow, Fundulus notatus, is a small freshwater fish in the family Fundulidae, found in central North America.


Blackstripe topminnows have a lifespan of around two to three years. They are normally found in water with a slow current where there is vegetation along the river bank which provides a good amount of cover along the waters edge. They tend to stay near the surface in summer and feed on insects. They also eat insect larvae in the water, as well as tiny molluscs, spiders and crustaceans. In the winter, they retreat to deeper water. Spawning occurs between May and August. Females lay 20 to 30 eggs; these are fertilized and tucked away in underwater vegetation one at a time by the males.


The blackstripe topminnow gets its name from the horizontal black stripe that runs the length of its body along its sides. The fish has a small mouth that turns slightly upward, and has a flat-topped head with a multi-coloured spot on it. The average length of this fish is between 5 and 7 cm. The males and females look distinct from one another. Males have dark vertical bars above and below their stripes, yellow-hued fins, and their dorsal and anal fins are longer and more pointed. Females have no bars, white fins and shorter, more rounded dorsal and anal fins.


Asian elephants inhabit grasslands, tropical evergreen forests, semi-evergreen forests, moist deciduous forests, dry deciduous forests and dry thorn forests, in addition to cultivated and secondary forests and scrublands. Over this range of habitat types elephants occur from sea level to over 3,000 m (9,800 ft). In the eastern Himalaya in northeast India, they regularly move up above 3,000 m (9,800 ft) in summer at a few sites.
In China, the Asian elephant survives only in the prefectures of Xishuangbanna, Simao, and Lincang of southern Yunnan. Estimated population is around 300 individual (in 2020).
In Bangladesh, some isolated populations survive in the south-east Chittagong Hills. A herd of 20–25 wild elephants was reported as being present in the Garo Hills of Mymensingh in the late-1990s, being detached from a big herd in the Peack hills of India and prevented from returning by fences put up in the meantime by the Indian border security force. The herd was estimated at about 60 individuals in 2014.
Three subspecies are recognised:
the Sri Lankan elephant occurs in Sri Lanka;
the Indian elephant occurs in mainland Asia: Bangladesh, Bhutan, Cambodia, China, India, Laos, Malay Peninsula, Myanmar, Nepal, Thailand, Vietnam;
the Sumatran elephant occurs in Sumatra.
The Borneo elephant occurs in Borneo's northeastern parts, primarily in Sabah (Malaysia), and sometimes in Kalimantan (Indonesia). In 2003, mitochondrial DNA analysis and microsatellite data indicated that the Borneo elephant population is derived from stock that originated in the region of the Sunda Islands. The genetic divergence of Borneo elephants warrants their recognition as a separate Evolutionarily Significant Unit.


Asian elephants are crepuscular. They are classified as megaherbivores and consume up to 150 kg (330 lb) of plant matter per day. They are generalist feeders, and are both grazers and browsers. They are known to feed on at least 112 different plant species, most commonly of the order Malvales, as well as the legume, palm, sedge and true grass families. They browse more in the dry season with bark constituting a major part of their diet in the cool part of that season. They drink at least once a day and are never far from a permanent source of fresh water. They need 80–200 litres of water a day and use even more for bathing. At times, they scrape the soil for clay or minerals.
Cows and calves move about together as groups, while bulls disperse from their mothers upon reaching adolescence. Bulls are solitary or form temporary "bachelor groups".
Cow-calf units generally tend to be small, typically consisting of three adults (most likely related females) and their offspring. Larger groups of as many as 15 adult females have also been recorded.
Seasonal aggregations of 17 individuals including calves and young adults have been observed in Sri Lanka's Uda Walawe National Park. Until recently, Asian elephants, like African elephants, were thought to be under the leadership of older adult females, or matriarchs. It is now recognized that cows form extensive and very fluid social networks, with varying degrees of associations between individuals. Social ties generally tend to be weaker than in African elephants.
Unlike African elephants, which rarely use their forefeet for anything other than digging or scraping soil, Asian elephants are more agile at using their feet in conjunction with the trunk for manipulating objects. They can sometimes be known for their violent behavior.
Asian elephants are recorded to make three basic sounds: growls, squeaks and snorts. Growls in their basic form are used for short distance communication. During mild arousal, growls resonate in the trunk and become rumbles while for long-distance communication, they escalate into roars. Low-frequency growls are infrasonic and made in many contexts. Squeaks come in two forms; chirpings and trumpets. Chirping consists of multiple short squeaks and signal conflict and nervousness. Trumpets are lengthened squeaks with increased loudness and produced during extreme arousal. Snorts signal changes in activity and increase in loudness during mild or strong arousal. During the latter case, when an elephant bounces the tip of the trunk it creates booms which serve as threat displays. Elephants are able to distinguish low-amplitude sounds.
Rarely, tigers have been recorded attacking and killing calves, especially if the calves become separated from their mothers, stranded from their herd, or orphaned. Adults are largely invulnerable to natural predation. There is a singular anecdotal case of a mother Asian elephant allegedly being killed alongside her calf; however, this account is contestable. In 2011 and 2014, two instances were recorded of tigers successfully killing adult elephants; one by a single tiger in Jim Corbett National Park on a 20-year-old elephant, and another on a 28-year-old elephant in Kaziranga National Park further east, which was taken down and eaten by several tigers hunting cooperatively.


The Asian elephant (Elephas maximus), also known as the Asiatic elephant, is the only living species of the genus Elephas and is distributed throughout the Indian subcontinent and Southeast Asia, from India in the west, Nepal in the north, Sumatra in the south, and to Borneo in the east. Three subspecies are recognised—E. m. maximus from Sri Lanka, E. m. indicus from mainland Asia and E. m. sumatranus from the island of Sumatra. Formerly, there was also the Syrian elephant or Western Asiatic elephant (Elephas maximus asurus) which was the westernmost population of the Asian elephant (Elephas maximus). This subspecies became extinct in ancient times. Skeletal remains of E. m. asurus have been recorded from the Middle East: Iran, Iraq, Syria, and Turkey from periods dating between at least 1800 BC and likely 700 BC. It is one of only three living species of elephants or elephantids anywhere in the world, the others being the African bush elephant and African forest elephant.
The Asian elephant is the largest living land animal in Asia. Since 1986, the Asian elephant has been listed as Endangered on the IUCN Red List, as the population has declined by at least 50 percent over the last three elephant generations, which is about 60–75 years. It is primarily threatened by loss of habitat, habitat degradation, fragmentation and poaching. In 2019, the wild population was estimated at 48,323-51,680 individuals.  Female captive elephants have lived beyond 60 years when kept in semi-natural surroundings, such as forest camps. In zoos, Asian elephants die at a much younger age; captive populations are declining due to a low birth and high death rate.
The genus Elephas originated in Sub-Saharan Africa during the Pliocene and spread throughout Africa before expanding into the southern half of Asia. The earliest indications of captive use of Asian elephants are engravings on seals of the Indus Valley civilisation dated to the 3rd millennium BC.


Bulls will fight one another to get access to oestrous cows. Strong fights over access to females are extremely rare. Bulls reach sexual maturity around the age of 12–15. Between the age of 10 and 20 years, bulls undergo an annual phenomenon known as "musth". This is a period where the testosterone level is up to 100 times greater than non-musth periods, and they become aggressive. Secretions containing pheromones occur during this period, from the paired temporal glands located on the head between the lateral edge of the eye and the base of the ear.
The gestation period is 18–22 months, and the cow gives birth to one calf, only occasionally twins. The calf is fully developed by the 19th month, but stays in the womb to grow so that it can reach its mother to feed. At birth, the calf weighs about 100 kg (220 lb), and is suckled for up to three years. Once a female gives birth, she usually does not breed again until the first calf is weaned, resulting in a four to five-year birth interval. Females stay on with the herd, but mature males are chased away.
Asian elephants reach adulthood at 17 years of age in both sexes. Average elephant life expectancy is 60 years in the wild and 80 in captivity, although this has been exaggerated in the past.
Generation length of the Asian elephant is 22 years.
Females produce sex pheromones. A principal component thereof, (Z)-7-dodecen-1-yl acetate, has also been found to be a sex pheromone in numerous species of insects.


Tusks serve to dig for water, salt, and rocks, to debark and uproot trees, as levers for maneuvering fallen trees and branches, for work, for display, for marking trees, as a weapon for offence and defence, as trunk-rests, and as protection for the trunk. Elephants are known to be right or left tusked.
Cows usually lack tusks; if tusks—in that case, called "tushes"—are present, they are barely visible and only seen when the mouth is open. The enamel plates of the molars are greater in number and closer together in Asian elephants. Some bulls may also lack tusks; these individuals are called "filsy makhnas", and are especially common among the Sri Lankan elephant population.
A record tusk described by George P. Sanderson measured 5 ft (1.5 m) along the curve, with a girth of 16 in (41 cm) at the point of emergence from the jaw, the weight being 104+1⁄2 lb (47.4 kg). This was from an elephant killed by Sir Brooke and measured 8 ft (2.4 m) in length, and nearly 17 in (43 cm) in circumference, and weighed 90 lb (41 kg). The tusk's weight was, however, exceeded by the weight of a shorter tusk of about 6 ft (1.8 m) in length which weighed 100 lb (45 kg).


It is commonly found in shallow reefs, from 2–46 metres (6.6–150.9 ft) deep, in the Pacific Ocean (Ryukyu, Mariana, Marshall, Marcus, Wake, and Hawaiian islands), west of Hawaii and east of Japan. There have also been reports that they have been found off the coast of Florida in the Western Central Atlantic. Their habitat is tropical with a temperature range of 24-28 degrees Celsius. Hawaii is the most common place for aquarium harvesting, where up to 70% of the yellow tangs for the aquarium industry are sourced from. Over 70% of the yellow tang's natural range is protected from collection and fishing. The yellow tang is listed as "Least Concern" by the International Union for Conservation of Nature (IUCN).
The yellow tang has been recorded in waters around Florida, where it is not native.


In the wild, yellow tangs feed on benthic turf algae and other marine plant material. In captivity, they are commonly fed meat/fish-based aquarium food, but the long term health effects of this diet are questionable. However, most experts in the marine aquarium industry express little scepticism that such a well rounded and balanced diet including plant and animal material would be in any way detrimental to mostly herbivorous fishes like tangs since they still need on occasion, complex amino acids and nutrients that only ocean animals can provide. In the wild, yellow tangs provide cleaner services to marine turtles, by removing algal growth from their shells.


The yellow tang has many natural predators, including larger fish, sharks, crabs, and octopuses.   Another threat is habitat destruction that is caused by humans.  Examples of habitat destruction caused by humans are pollution that started on land and flows into the water, physical damage and destruction from harmful fishing practices, as well as overfishing, coral harvesting,  and snorkeling, which can potentially cause reef damage.


Adult fish can grow to 20 centimetres (7.9 in) in length, and 1–2 centimetres (0.39–0.79 in) in thickness. Adult males tend to be larger than females. Yellow tangs are bright yellow in color. At night, the yellow coloring fades slightly, and a prominent brownish patch develops in the middle with a horizontal white band. They rapidly regain their bright yellow color during daylight. They can be aggressive, are prone to marine ich, and may damage coral within a reef tank. Male and female yellow tang look very similar. When mating, however, males change color and have a "shimmering" behavior which makes them identifiable.  The yellow tang has 5 dorsal spines along with 23-26 dorsal soft rays.  The yellow tang also has 3 anal spines as well as 19-22 anal soft rays.  There is a white spine on its caudal peduncle that it can use for defense.  Its snout is moderately protruding.  Its mouth is small with spatulate teeth that are place classed relatively close together inside of the yellow tang’s mouth.  In juveniles, there are 12 upper and 14 lower teeth.  In adults, there are 18 upper and 22 lower teeth.
The yellow tang is a marine fish that lives in reefs. The yellow tang is found by itself or in very small groups/schools. The yellow tang is mainly herbivorous and eats filamentous algae.


The Moorish idol (Zanclus cornutus) is a marine fish species, the sole extant representative of the family Zanclidae (from the Greek ζαγκίος, zagkios, "oblique") in order Acanthuriformes.  A common inhabitant of tropical to subtropical reefs and lagoons, the Moorish idol is notable for its wide distribution throughout the Indo-Pacific.  A number of butterflyfishes (genus Heniochus) closely resemble the Moorish idol. It is closely related to, if not a direct descendant of, the extinct Eozanclus brevirostris, from the Middle Eocene of Monte Bolca.
The Moorish idol got its name from the Moors of Africa, who purportedly believed the fish to be a bringer of happiness.  Moorish idols are also a coveted aquarium fish but, despite their abundance and wide array of habitats, they are notoriously finicky and hard to adjust to captivity. Their omnivorous diet can be extremely difficult to replicate in aquaria, as the vegetation which they live on is normally exterminated and they have a habit of eating corals and sponges.


Generally denizens of shallow waters, Moorish idols prefer flat reefs. This fish may be found at depths from 0.3 to 180 m (1 ft 0 in to 590 ft 7 in), in both murky and clear conditions. Their range includes: East Africa, the Indian Ocean, Persian Gulf, the Ducie Islands, Hawaii, southern Japan and all of Micronesia; they are also found from the southern Gulf of California south to Peru.


Sponges, coral polyps, tunicates and other benthic invertebrates constitute the bulk of the Moorish idol's diet.


With distinctively compressed and disk-like bodies, Moorish idols stand out in contrasting bands of black, white and yellow, which makes them attractive to aquarium keepers. The fish have relatively small fins, except for the dorsal fin, whose six or seven spines are dramatically elongated to form a trailing, sickle-shaped crest called the philomantis extension. Moorish idols have small terminal mouths at the end of long, tubular snouts; many long bristle-like teeth line the mouth. The Moorish idol differs from butterflyfish in having a prominent black, triangular anal fin.
The eyes are set high on the fish's deeply keeled body; in adults, perceptible bumps are located above each. The anal fin may have two or three spines. Moorish idols reach a maximum length of 23 cm (9.1 in). The sickle-like dorsal spines shorten with age.


The hippopotamus (/ˌhɪpəˈpɒtəməs/ HIP-ə-POT-ə-məs; Hippopotamus amphibius), also called the hippo, common hippopotamus, or river hippopotamus, is a large semiaquatic mammal native to sub-Saharan Africa. It is one of only two extant species in the family Hippopotamidae, the other being the pygmy hippopotamus (Choeropsis liberiensis or Hexaprotodon liberiensis). Its name comes from the ancient Greek for "river horse" (ἱπποπόταμος).
Aside from elephants and rhinos, the hippopotamus is the largest land mammal. It is also the largest extant land artiodactyl. Despite their physical resemblance to pigs and other terrestrial even-toed ungulates, the closest living relatives of the Hippopotamidae are cetaceans (whales, dolphins, porpoises, etc.), from which they diverged about 55 million years ago. Hippos are recognisable for their barrel-shaped torsos, wide-opening mouths with large canine tusks, nearly hairless bodies, pillar-like legs, and large size: adults average 1,500 kg (3,310 lb) for bulls (males) and 1,300 kg (2,870 lb) for cows (females). Despite its stocky shape and short legs, it is capable of running 30 km/h (19 mph) over short distances.
Hippos inhabit rivers, lakes, and mangrove swamps. Territorial bulls each preside over a stretch of water and a group of five to thirty cows and calves. Reproduction and birth both occur in the water. During the day, hippos remain cool by staying in water or mud, emerging at dusk to graze on grasses. While hippos rest near each other in the water, grazing is a solitary activity and hippos typically do not display territorial behaviour on land. Hippos are among the most dangerous animals in the world due to their highly aggressive and unpredictable nature. They are threatened by habitat loss and poaching for their meat and ivory (canine teeth).


The hippopotamus is a megaherbivore and is exceeded in size among land animals only by elephants and some rhinoceros species. The mean adult weight is around 1,480 kg (3,260 lb) for bulls and 1,365 kg (3,010 lb) for cows. Exceptionally large males have been recorded reaching 2,660 kg (5,860 lb). Male hippos appear to continue growing throughout their lives, while females reach maximum weight at around age 25. Hippos measure 2.90 to 5.05 m (9.5 to 16.6 ft) long, including a tail of about 35 to 56 cm (1.15 to 1.84 ft) in length and 1.30 to 1.65 m (4.3 to 5.4 ft) tall at the shoulder, with males and females ranging 1.40 to 1.65 m (4.6 to 5.4 ft) and 1.30 to 1.45 m (4.3 to 4.8 ft) tall at the shoulder respectively. The species has a typical head-body length of 3.3–3.45 m (10.8–11.3 ft) and an average standing height of 1.4 m (4.6 ft) at the shoulder.
Hippos have barrel-shaped bodies with short tails and legs, and an hourglass-shaped skull with a long muzzle. Their skeletal structures are graviportal, adapted to carrying their enormous weight, and their dense bones and low centre of gravity allows them to sink and move along the bottom of the water. Hippopotamuses have small legs (relative to other megafauna) because the water in which they live reduces the weight burden. The pelvis rests at an angle of 45 degrees. Though they are bulky animals, hippos can gallop at 30 km/h (19 mph) on land, but they normally trot. They are incapable of jumping but do climb up steep banks.
The eyes, ears, and nostrils of hippos are placed high on the roof of their skulls. This allows these organs to remain above the surface while the rest of the body is submerged. Muscular closing valves exist in the nostrils while nictitating membranes cover the eyes. Despite being semiaquatic and having webbed feet, an adult hippo is not a particularly good swimmer, nor can it float. It is rarely found in deep water; when it is, the animal moves by porpoise-like leaps off the bottom. Adult hippos move at speeds of up to 8 km/h (5 mph) in water, typically resurfacing to breathe every three to five minutes. The young have to breathe every two to three minutes. The hippopotamus sleeps with both hemispheres of the brain resting, as in all land mammals. Despite this, it is able to sleep while submerged, intermittently surfacing to breathe seemingly without waking. They may be able to transition between different phases of sleep more quickly than other mammals.
The hippo's jaw is powered by a large masseter and a well-developed digastric; the latter loops up behind the former to the hyoid. The jaw hinge is located far back enough to allow the animal to open its mouth at almost 180°. A moderate folding of the orbicularis oris muscle allows the hippo to achieve such a large gape without tearing any tissue. Hippo teeth sharpen themselves as they grind together. The lower canines and lower incisors are enlarged, especially in bulls, and grow continuously. The incisors can reach 40 cm (1 ft 4 in), while the canines can grow to up to 50 cm (1 ft 8 in). The canines and incisors are used for combat and play no role in feeding. Hippos rely on their broad, rough lips to grasp and pull grasses which are then ground by the molars. The hippo is considered to be a pseudoruminant; it has a complex three-chambered stomach, but does not "chew cud".
Unlike most other semiaquatic animals, hippos have very little hair. The skin is 6 cm (2 in) thick, providing the hippo with great protection against predators and other hippos. By contrast, its subcutaneous fat layer is thin. The animals' upper parts are purplish-grey to blue-black, while the under parts and areas around the eyes and ears can be brownish-pink. Their skin secretes a natural, red-coloured sunscreen substance that is sometimes referred to as "blood sweat" but is neither blood nor sweat. This secretion is initially colourless and turns red-orange within minutes, eventually becoming brown. Two highly acidic pigments have been identified in the secretions; one red (hipposudoric acid) and one orange (norhipposudoric acid), which inhibit the growth of disease-causing bacteria and their light-absorption profile peaks in the ultraviolet range, creating a sunscreen effect. Regardless of diet, all hippos secrete these pigments so food does not appear to be their source; rather, they may be synthesised from precursors such as the amino acid tyrosine. This natural sunscreen cannot prevent the animal's skin from cracking if it stays out of water too long.
The testes of the males descend only partially and a scrotum is not present. In addition, the penis retracts into the body when not erect. The genitals of the female hippos are unusual in that the vagina is ridged and two large diverticula protrude from the vulval vestibule. The function of these is unknown.
A hippo's lifespan is typically 40 to 50 years. Donna the Hippo was one of the oldest living hippos in captivity. She lived at the Mesker Park Zoo in Evansville, Indiana, in the US until her death in 2012 at the age of 61. The oldest hippo ever recorded was called Bertha; she had lived in the Manila Zoo in the Philippines since it first opened in 1959. When she died in 2017, her age was estimated to be 65.


Cows reach sexual maturity at five to six years of age and have a gestation period of eight months. A study of endocrine systems revealed cows may begin puberty at as early as three or four years. Males reach maturity at around 7.5 years. A study of hippo reproductive behaviour in Uganda showed that peak conceptions occurred during the end of the wet season in the summer, and peak births occurred toward the beginning of the wet season in late winter. This is because of the female's oestrous cycle; as with most large mammals, male hippo spermatozoa is active year-round. Studies of hippos in Zambia and South Africa also showed evidence of births occurring at the start of the wet season. After becoming pregnant, a female hippo will typically not begin ovulation again for 17 months.
Mating occurs in the water, with the cow submerged for most of the encounter, her head emerging periodically to draw breath. Cows isolate themselves to give birth and return to the pod within 10 to 14 days. Calves are born underwater weighing between 25 and 50 kg (55 and 110 lb) and at an average length of around 127 cm (4.17 ft). They must swim to the surface to take their first breaths. A mother typically gives birth to only one calf, though sometimes they give birth to twins. The young often rest on their mothers' backs when the water is too deep for them, and they swim under water to suckle. They will suckle on land as well when the mother leaves the water.
Mother hippos are very protective of their young and may keep others at a distance. One cow was recorded protecting a calf's carcass after it had died. Calves are occasionally left in nurseries which are guarded by one or a few adults. Calves in nurseries often engage in playfights. Weaning starts between six and eight months after birth, and most calves are fully weaned after a year. Like many other large mammals, hippos are described as K-strategists, in this case typically producing just one large, well-developed infant every couple of years (rather than many small, poorly developed young several times per year, as is common among small mammals such as rodents).


The groundhog prefers open country and the edges of woodland, and is rarely far from a burrow entrance. Marmota monax has a wide geographic range. It is typically found in low-elevation forests, small woodlots, fields, pastures, and hedgerows. It constructs dens in well-drained soil, and most have summer and winter dens. Human activity has increased food access and abundance, allowing M. monax to thrive.


Mostly herbivorous, groundhogs eat primarily wild grasses and other vegetation, including berries and agricultural crops, when available. In early spring, dandelion and coltsfoot are important groundhog food items. Some additional foods include sheep sorrel, timothy-grass, buttercup, tearthumb, agrimony, red and black raspberries, mulberries, buckwheat, plantain, wild lettuce, all varieties of clover, and alfalfa. Groundhogs also occasionally eat small animals, such as grubs, grasshoppers, snails, and even baby birds, but are not as omnivorous as many other Sciuridae.
An adult groundhog can eat more than a pound of vegetation daily. In early June, woodchucks' metabolism slows, and while their food intake decreases, their weight increases by as much as 100% as they produce fat deposits to sustain them during hibernation and late winter. Instead of storing food, groundhogs stuff themselves to survive the winter without eating. Thought not to drink water, groundhogs are reported to obtain needed liquids from the juices of food-plants, aided by their sprinkling with rain or dew.


In the wild, groundhogs can live up to six years with two or three being average. In captivity, groundhogs reportedly live up to 14 years. Human development, which often produces openings juxtaposed with second growth trees that are incidentally also favored by groundhogs, often ensures that groundhogs in well-developed areas are nearly free of predators, beyond humans (through various forms of pest control or roadkills) or mid-to-large sized dogs.
Wild predators of adult groundhogs in most of eastern North America include coyotes, badgers, bobcats, and foxes (largely only red fox). Many of these predators are successful stealth stalkers so can catch groundhogs by surprise before the large rodents can escape to their burrows; badgers likely hunt them by digging them out from their burrows. Coyotes in particular are sizable enough to overpower any groundhog, with the latter being the third most significant prey species per a statewide study in Pennsylvania.
Large predators such as gray wolf and eastern cougar are basically extirpated in the east but still may hunt groundhogs on occasion in Canada. Golden eagles can also prey on adult groundhogs, but seldom occur in the same range or in the same habitats as this marmot. Likewise, great horned owls can reportedly, per Bent (1938), prey upon groundhogs, but this owl rarely does so, especially given the temporal differences in their behaviors.
Young groundhogs (usually those less than a couple months in age) may also be taken by an American mink, perhaps other smallish mustelids, cats, timber rattlesnakes, and hawks. Red-tailed hawks can take groundhogs at least of up to the size of yearling juveniles, and northern goshawks can take them up to perhaps weak emergent-adult groundhogs in the Spring.
Beyond their large size, groundhogs have several successful anti-predator behaviors, usually retreating to the safety of their burrow which most predators will not attempt to enter, but also being ready to fight off with their sharp claws and large incisors any who press the attack. They can also scale trees to escape a threat.
Occasionally, woodchucks may suffer from parasitism and a woodchuck may die from infestation or from bacteria transmitted by vectors. In areas of intensive agriculture and the dairying regions of the state of Wisconsin, particularly in its southern parts, the woodchuck by 1950 had been almost extirpated. Jackson (1961) suggested that exaggerated reports of damage done by the woodchuck led to excessive culling, substantially reducing its numbers in the state.
In some areas woodchucks are important game animals and are killed regularly for sport, food, or fur. In Kentucky, an estimated 267,500 M. monax were taken annually from 1964 to 1971 (Barbour and Davis 1974). Woodchucks had protected status in the state of Wisconsin until 2017. Woodchuck numbers appear to have decreased in Illinois.


The groundhog (Marmota monax), also known as a woodchuck, is a rodent of the family Sciuridae, belonging to the group of large ground squirrels known as marmots.
The groundhog is a lowland creature of North America; it is found through much of the Eastern United States, across Canada and into Alaska.
It was first scientifically described by Carl Linnaeus in 1758.
The groundhog is also referred to as a chuck, wood-shock, groundpig, whistlepig, whistler, thickwood badger, Canada marmot, monax, moonack, weenusk, red monk, land beaver, and, among French Canadians in eastern Canada, siffleux. The name "thickwood badger" was given in the Northwest to distinguish the animal from the prairie badger. Monax (Móonack) is an Algonquian name of the woodchuck, which means "digger" (cf. Lenape monachgeu). Young groundhogs may be called chucklings.
The groundhog, being a lowland animal, is exceptional among marmots. Other marmots, such as the yellow-bellied and hoary marmots, live in rocky and mountainous areas. Groundhogs play an important role maintaining healthy soil in woodlands and plains. The groundhog is considered a crucial habitat engineer. Groundhogs are considered the most solitary of the marmot species. They live in aggregations, and their social organization also varies across populations. Groundhogs do not form stable, long-term pair-bonds, and during mating season male-female interactions are limited to copulation. In Ohio, adult males and females associate with each other throughout the year and often from year to year. Groundhogs are an extremely intelligent animal forming complex social networks, able to understand social behavior, form kinship with their young, understand and communicate threats through whistling, and work cooperatively to solve tasks such as burrowing.


Usually groundhogs breed in their second year, but a small proportion may breed in their first. The breeding season extends from early March to mid- or late April, after hibernation. Woodchucks are polygynous  but only alpine and woodchuck marmot females have been shown to mate with multiple males. A mated pair remains in the same den throughout the 31- to 32-day gestation period. As birth of the young approaches in April or May, the male leaves the den. One litter is produced annually. Female woodchucks give birth to one to nine offspring, with most litters ranging between 3 and 5 pups. Groundhog mothers introduce their young to the wild once their fur is grown in and they can see. At this time, if at all, the father groundhog comes back to the family. By the end of August, the family breaks up; or at least, the larger number scatter, to burrow on their own.


The time spent observing groundhogs by field biologists represents only a small fraction of time devoted to the field research. W.J. Schoonmaker reports that groundhogs may hide when they see, smell, or hear an observer. Marmot researcher Ken Armitage states that the social biology of the groundhog is poorly studied.
Despite their heavy-bodied appearance, groundhogs are accomplished swimmers and occasionally climb trees when escaping predators or when they want to survey their surroundings. They prefer to retreat to their burrows when threatened; if the burrow is invaded, the groundhog tenaciously defends itself with its two large incisors and front claws. Groundhogs are generally agonistic and territorial among their own species and may skirmish to establish dominance.
Outside their burrow, individuals are alert when not actively feeding. It is common to see one or more nearly motionless individuals standing erect on their hind feet watching for danger. When alarmed, they use a high-pitched whistle to warn the rest of the colony, hence the name "whistle-pig". Groundhogs may squeal when fighting, seriously injured, or caught by a predator. Other sounds groundhogs may make include low barks and a sound produced by grinding their teeth. David P. Barash wrote that he witnessed only two occasions of upright play-fighting among woodchucks and that the upright posture of play-fighting involves sustained physical contact between individuals and may require a degree of social tolerance virtually unknown in M. monax. He said it was possible to conclude, alternatively, that upright play-fighting is part of the woodchuck's behavioral repertory but rarely shown because of physical spacing and/or low social tolerance.


In the United Kingdom and Ireland, the grey seal breeds in several colonies on and around the coasts.  Notably large colonies are at Blakeney Point in Norfolk, Donna Nook in Lincolnshire, the Farne Islands off the Northumberland Coast (about 6,000 animals), Orkney and North Rona. off the north coast of Scotland, Lambay Island off the coast of Dublin and Ramsey Island off the coast of Pembrokeshire. In the German Bight, colonies exist off the islands Sylt and Amrum and on Heligoland.
In the Western North Atlantic, the grey seal is typically found in large numbers in the coastal waters of Canada and south to Nantucket in the United States. In Canada, it is typically seen in areas such as the Gulf of St. Lawrence, Newfoundland, the Maritimes, and Quebec. The largest colony in the world is at Sable Island, NS. In the United States it is found year-round off the coast of New England, in particular Maine and Massachusetts. Archaeological evidence confirms grey seals in southern New England with remains found on Block Island, Martha's Vineyard and near the mouth of the Quinnipiac River in New Haven, Connecticut. Its natural range now extends much further south than previously recognised with confirmed sightings in North Carolina. Also, there is a report by Farley Mowat of historic breeding colonies as far south as Cape Hatteras, North Carolina.
An isolated population exists in the Baltic Sea, forming the H. grypus balticus subspecies.
Besides these very large colonies, many much smaller ones exist, some of which are well known as tourist attractions despite their small size. Such colonies include one on the Carrack rocks in Cornwall.
During the winter months, grey seals can be seen hauled out on rocks, islands, and shoals not far from shore, occasionally coming ashore to rest. In the spring recently weaned pups and yearlings occasionally strand on beaches after becoming separated from their group.
Grey seals are vulnerable to typical predators for a pinniped mammal. Large sharks are known to prey on grey seals in Canada, particularly great white sharks but also, upon evidence, additionally Greenland sharks. In the waters of Great Britain, grey seals are a fairly common prey species for killer whales. Apparently, grey seal pups are sometimes taken alive by white-tailed eagles, as well.


The grey seal feeds on a wide variety of fish, mostly benthic or demersal species, taken at depths down to 70 m (230 ft) or more. Sand eels (Ammodytes spp) are important in its diet in many localities. Cod and other gadids, flatfish, herring, wrasse and skates are also important locally. However, it is clear that the grey seal will eat whatever is available, including octopus and lobsters. The average daily food requirement is estimated to be 5 kg (11 lb), though the seal does not feed every day and it fasts during the breeding season.
Recent observations and studies from Scotland, The Netherlands, and Germany show that grey seals will also prey and feed on large animals like harbour seals and harbour porpoises. In 2014, a male grey seal in the North Sea was documented and filmed killing and cannibalising 11 pups of his own species over the course of a week. Similar wounds on the carcasses of pups found elsewhere in the region suggest that cannibalism and infanticide may not be uncommon in grey seals. Male grey seals may engage in such behaviour potentially as a way of increasing reproductive success through access to easy prey without leaving prime territory.


While it was originally understood that marine mammals communicate vocally, new research conducted by researchers at Monash University shows that grey seals clap their flippers as another form of communication. They clap their flippers underwater to deter a predator from attacking. If done during the mating season, the clapping can be used as a way to find a potential mate. The Monash researchers point out that seals are typically known for clapping, so this behavior may not be a surprise, but the clapping we know typically occurs in captivity. Clapping seals are associated with aquariums and zoos, but were never observed in the wild for this behavior. They were astonished at how loud these marine mammals were able to clap underwater, but it is logical for the reasons they do this.


Grey seals are capital breeders; they forage to build up stored blubber, which is utilised when they are breeding and weaning their pups, as they do not forage for food at this time. They give birth to a single pup every year, with females' reproductive years beginning as early as 4 years old and extending up to 30 years of age. All parental care is provided by the female. During breeding, males don't provide parental care but they defend females against other males for mating. The pups are born at around the mass of 14 kg. They are born in autumn (September to December) in the eastern Atlantic and in winter (January to February) in the west, with a dense, soft silky white fur; at first small, they rapidly fatten up on their mothers' extremely fat-rich milk. The milk can consist of up to 60% fat.  Grey seal pups are precocial, with mothers returning to the sea to forage once pups are weaned. Pups also undergo a post-weaning fast before leaving the land and learning to swim. Within a month or so they shed the pup fur, grow dense waterproof adult fur, and leave for the sea to learn to fish for themselves. In recent years, the number of grey seals has been on the rise in the west and the U.S. and Canada there have been calls for a seal cull.
Seal pup first-year survival rates are estimated to vary from 80 to 85% to below 50% depending on location and conditions. Starvation, due to difficulties in learning to feed, appears to be the main cause of pup death.


Douglas squirrels live in coniferous forest habitats along the Pacific Coast, from the Sierra Nevada (mountains) of California, northwards to the southwestern coast of British Columbia. Tamiasciurus douglasii prefer old-growth forests or mature second-growth forests, and some authors regard them as dependent on its presence. Mearns's squirrel is a distinctive subspecies of the Douglas squirrel that instead inhabits xeric pine forests in a small portion of Baja California.
Throughout most their range, Douglas squirrels essentially replace the American Red Squirrel, which inhabits the coniferous forests of the rest of North America, in these areas.  The two species have very minimal overlap in the territory.
Douglas squirrels are territorial; in winter, each squirrel occupies a territory of about 10 000 square metres, but during the breeding season a mated pair will defend a single territory together. Douglas squirrels are active by day, throughout the year, often chattering noisily at intruders. On summer nights, they sleep in ball-shaped nests that they make in the trees, but in the winter they use holes in trees as nests. Groups of squirrels seen together during the summer are likely to be juveniles from a single litter.


Douglas squirrels mostly eat seeds of coniferous trees such as Douglas fir (Pseudotsuga menziesii), Sitka spruce (Picea sitchensis) and shore pine (Pinus contorta). They also eat the fleshy scales of green giant sequoia cones, as well as acorns, berries, mushrooms, the eggs of birds such as yellow warblers, and some fruit including strawberries and plums.  Douglas squirrels are larder hoarders, storing their food in a single location or 'larder' called a midden. As the squirrel peels the scales of cones to get at the seeds, the discarded scales accumulate into piles that can grow to several meters across as the same site is used by generations of squirrels.
Their predators include American martens, Bobcats, domestic cats, northern goshawks, and owls; although they quickly acclimatize to human presence, humans can be a threat to them, through robbing of their cone caches to find seeds for tree cultivation and through the destruction of old-growth forest. However, the squirrels' numbers appear to be unaffected by commercial thinning of forests.


The Douglas squirrel (Tamiasciurus douglasii) is a pine squirrel found in the Pacific Northwest of North America, including the northwestern coastal states of the United States as well as the southwestern coast of British Columbia in Canada, with an isolated subspecies in northern Baja California. It is sometimes known as the chickaree or pine squirrel, although these names are also used for the American red squirrel.  Variant spellings of the common name are Douglas' squirrel and  Douglas's squirrel. The Native Americans of Kings River called it the "Pillillooeet", in imitation of its characteristic alarm call.


John Muir described the Douglas squirrel, Tamiasciurus douglasii, as "by far the most interesting and influential of the California Sciuridæ". Adults are about 33 cm in length (including its tail, which is about 13 cm long), and weigh between 150 and 300 grams. Their appearance varies according to the season. In the summer, they are greyish or almost greenish-brown on their backs, and pale orange on the chest and belly, while legs and feet appear brown. In the winter, the coat is browner and the underside is grayer; also, the ears appear even tuftier than they do in summer. Like many squirrels, Douglas squirrels have a white eye-ring.


Mating can occur as early as February. Gestation is about four weeks, and the young (which are altricial) are weaned at about eight weeks of age. There may be up to six kits in a litter, though four is more usual. In the southern and lower parts of their range, they produce two litters each year.


The European hare is native to much of continental Europe and part of Asia. Its range extends from northern Spain to southern Scandinavia, eastern Europe, and northern parts of Western and Central Asia. It has been extending its range into Siberia. It may have been introduced to Great Britain by the Romans about 2000 years ago, based on a lack of archaeological evidence before that. It is not present in Ireland, where the mountain hare is the only native hare species. Undocumented introductions probably occurred in some Mediterranean Islands. It has also been introduced, mostly as game animal, to North America in Ontario and New York State, and unsuccessfully in Pennsylvania, Massachusetts, and Connecticut, the Southern Cone in Brazil, Argentina, Uruguay, Paraguay, Bolivia, Chile, Peru and the Falkland Islands, Australia, both islands of New Zealand and the south Pacific coast of Russia.
The European hare primarily lives in open fields with scattered brush for shelter. It is very adaptable and thrives in mixed farmland. According to a study in the Czech Republic, the mean hare densities were highest at elevations below 200 m (660 ft), 40 to 60 days of annual snow cover, 450 to 700 mm (18 to 28 in) of annual precipitation, and a mean annual air temperature of around 10 °C (50 °F). With regards to climate, the European hare density was highest in "warm and dry districts with mild winters". In Poland, the European hare is most abundant in areas with few forest edges, perhaps because foxes can use these for cover. It requires cover, such as hedges, ditches and permanent cover areas, because these habitats supply the varied diet it requires, and are found at lower densities in large open fields. Intensive cultivation of the land results in greater mortality of young hares.
In Great Britain, the European hare is seen most frequently on arable farms, especially those with crop rotation and fallow land, wheat and sugar beet crops. In mainly grass farms, its numbers increased with are improved pastures, some arable crops and patches of woodland. It is seen less frequently where foxes are abundant or where there are many common buzzards. It also seems to be fewer in number in areas with high European rabbit populations, although there appears to be little interaction between the two species and no aggression. Although European hares are shot as game when plentiful, this is a self-limiting activity and is less likely to occur in localities where the species is scarce.


The European hare (Lepus europaeus), also known as the brown hare, is a species of hare native to Europe and parts of Asia. It is among the largest hare species and is adapted to temperate, open country. Hares are herbivorous and feed mainly on grasses and herbs, supplementing these with twigs, buds, bark and field crops, particularly in winter. Their natural predators include large birds of prey, canids and felids. They rely on high-speed endurance running to escape predation, having long, powerful limbs and large nostrils.
Generally nocturnal and shy in nature, hares change their behaviour in the spring, when they can be seen in broad daylight chasing one another around in fields. During this spring frenzy, they sometimes strike one another with their paws ("boxing"). This is usually not competition between males, but a female hitting a male, either to show she is not yet ready to mate or to test his determination. The female nests in a depression on the surface of the ground rather than in a burrow and the young are active as soon as they are born. Litters may consist of three or four young and a female can bear three litters a year, with hares living for up to twelve years. The breeding season lasts from January to August.
The European hare is listed as being of least concern by the International Union for Conservation of Nature because it has a wide range and is moderately abundant. However, populations have been declining in mainland Europe since the 1960s, at least partly due to changes in farming practices. The hare has been hunted across Europe for centuries, with more than five million being shot each year; in Britain, it has traditionally been hunted by beagling and hare coursing, but these field sports are now illegal. The hare has been a traditional symbol of fertility and reproduction in some cultures and its courtship behaviour in the spring inspired the English idiom mad as a March hare.


European hares have a prolonged breeding season which lasts from January to August. Females, or does, can be found pregnant in all breeding months and males, or bucks, are fertile all year round except during October and November. After this hiatus, the size and activity of the males' testes increase, signalling the start of a new reproductive cycle. This continues through December, January and February when the reproductive tract gains back its functionality. Matings start before ovulation occurs and the first pregnancies of the year often result in a single foetus, with pregnancy failures being common. Peak reproductive activity occurs in March and April, when all females may be pregnant, the majority with three or more foetuses.
The mating system of the hare has been described as both polygynous (single males mating with multiple females) and promiscuous. Females have six-weekly reproductive cycles and are receptive for only a few hours at a time, making competition among local bucks intense. At the height of the breeding season, this phenomenon is known as "March madness", when the normally nocturnal bucks are forced to be active in the daytime. In addition to dominant animals subduing subordinates, the female fights off her numerous suitors if she is not ready to mate. Fights can be vicious and can leave numerous scars on the ears. In these encounters, hares stand upright and attack each other with their paws, a practice known as "boxing", and this activity is usually between a female and a male and not between competing males as was previously believed. When a doe is ready to mate, she runs across the countryside, starting a chase that tests the stamina of the following males. When only the fittest male remains, the female stops and allows him to copulate. Female fertility continues through May, June and July, but testosterone production decreases in males and sexual behaviour becomes less overt. Litter sizes decrease as the breeding season draws to a close with no pregnancies occurring after August. The testes of males begin to regress and sperm production ends in September.
Does give birth in hollow depressions in the ground. An individual female may have three litters in a year with a 41- to 42-day gestation period. The young have an average weight of around 130 grams (4.6 oz) at birth. The leverets are fully furred and are precocial, being ready to leave the nest soon after they are born, an adaptation to the lack of physical protection relative to that afforded by a burrow. Leverets disperse during the day and come together in the evening close to where they were born. Their mother visits them for nursing soon after sunset; the young suckle for around five minutes, urinating while they do so, with the doe licking up the fluid. She then leaps away so as not to leave an olfactory trail, and the leverets disperse once more. Young can eat solid food after two weeks and are weaned when they are four weeks old. While young of either sex commonly explore their surroundings, natal dispersal tends to be greater in males. Sexual maturity occurs at seven or eight months for females and six months for males.


Sika deer are found in the temperate and subtropical forests of eastern Asia, preferring areas with dense understory, and where snowfall does not exceed 10–20 cm (4–8 in). They tend to forage in patchy clearings of forests. Introduced populations are found in areas with similar habitats to their native ranges, including Western and Central Europe, Eastern United States, and New Zealand.


Sika deer inhabit temperate and subtropical woodlands, often in areas suitable for farming and other human exploitation. Their range encompasses some of the most densely populated areas in the world, where forests were cleared hundreds of years ago. Their population status varies significantly in different countries. Although the species as a whole is thriving, it is endangered and extinct in many areas.
Japan has by far the largest native sika population in the world. Though the exact population is uncertain, it is likely to be in the hundred thousand range and is still increasing, mainly due to recent conservation efforts and the extinction of its main predator, the Japanese wolf (Canis lupus hodophilax), over a century ago. Without its main predator, the population of sika exploded and it is now overpopulated in many areas, posing a threat to both forests and farmlands. Efforts are now being made to control its population instead of conserving it. None of its subspecies is endangered except the Kerama deer (C. n. keramae) on the tiny Kerama Islands.
In 2015, Japanese Ministry of the Environment estimated the population at 3,080,000 in Japan, including Hokkaido.
China used to have the largest population of sika, but thousands of years of hunting and habitat loss have reduced the population to less than 1,000. Of the five subspecies in China, the North China sika deer (C. n. mandarinus) is believed to be extinct in the wild since the 1930s; the Shanxi sika deer (C. n. grassianus) has not been seen in the wild since the 1980s and is also believed to be extinct in the wild. The status of Manchurian sika deer in China is unclear, though it is also believed to be extinct, and the sightings there are actually feral populations.
The South China sika deer (C. n. kopschi) and Sichuan sika deer (C. n. sichuanicus) are the only subspecies known to remain in the wild. The former exists in fragmented populations of around 300 in southeast China, while the latter is found in a single population of over 400. The feral population is likely to be much higher than the wild, though most of them are descended from domesticated sikas of mixed subspecies. All of the subspecies are present in captivity, but a lack of suitable habitats and government efforts prevent their reintroduction.
The Formosan sika deer (C. n. taioanus) has been extinct in the wild for almost two decades before individuals from zoos were introduced to Kenting National Park; the population now numbers 200. Reintroduction programs are also under way in Vietnam, where the Vietnamese sika deer (C. n. pseudaxis) is extinct or nearly so.
Russia has a relatively large and stable population of 8,500–9,000 individuals of the Manchurian subspecies, but this is limited to a small area in Primorsky Krai. Small populations might exist in North Korea, but the political situation makes investigation impossible. The species is extinct in South Korea, with no plans for reintroduction.


The sika deer (Cervus nippon), also known as the spotted deer or the Japanese deer, is a species of deer native to much of East Asia and introduced to other parts of the world. Previously found from northern Vietnam in the south to the Russian Far East in the north, it is now uncommon except in Japan, where the species is overabundant.


Sika deer can be active throughout the day, though in areas with heavy human disturbance, they tend to be nocturnal. Seasonal migration is known to occur in mountainous areas, such as Japan, with winter ranges being up to 700 m (2,300 ft) lower in elevation than summer ranges.
Lifestyles vary between individuals, with some occurring alone while others are found in single-sex groups. Large herds gather in autumn and winter. Males spend most years alone occasionally forming herds together. Females with fawns only form herds during birthing season. The sika deer is a highly vocal species, with over 10 individual sounds, ranging from soft whistles to loud screams.
Sika males are territorial and keep harems of females during their rut, which peaks from early September through November, but may last well into the winter. Territory size varies with habitat type and size of the buck; strong, prime bucks may hold up to two hectares (five acres). Territories are marked by a series of shallow pits or "scrapes", which is digging holes (up to 1.6 m in wide and 0.3 m in deep) with forefeet or antlers, into which the males urinate and from which emanates a strong, musky odor. Fights between rival males for territorial disputes, which occur by using hooves and antlers, are sometimes fierce and long and may even be fatal.
The gestation period lasts for seven months. Hinds (does) give birth to a single fawn, weighing 4.5 to 7 kg (10 to 15 lb), which is nursed for up to ten months. The mother hides her fawn in thick undergrowth immediately after giving birth, and the fawn stays very quiet and still while it waits until the mother returns to nurse it. The fawn becomes independent 10 to 12 months after birth, and attains sexual maturity at 16 to 18 months in both sexes. The average lifespan is 15 to 18 years in captivity, although one case is recorded as living 25 years and 5 months.
The sika deer may interbreed with the red deer, the closest relative; hybrid descendants may have adaptive advantages over purebred relatives.
In Nara Prefecture, Japan, the deer are also known as "bowing deer", as they bow their heads before being fed special shika senbei (鹿せんべい, called "deer cookies"). However, deer bow heads to signal that they are about to headbutt. Therefore, when a human "bows" to a deer, the deer may take it as a challenge, and will assume the same stance before charging and attempting to headbutt the person. Deer headbutt both for play and to assert dominance, as do goats. Sika deer are found throughout the city of Nara and its many parks and temples like Tōdai-ji, as they are considered to be the messengers of the Shinto gods.


Lasionycteris noctivagans is found in Bermuda, Canada, Mexico, and the United States. This forest inhabitant is known to occur from southeastern Alaska in summer to northeastern Mexico in winter  and is found in arid habitats at low elevations during seasonal migrations. In Missouri, reproduction occurs in the northern dissected plains region, but reproductive females are believed to be absent from the southern Ozark highlands in the summer.
They often roost in tree cavities or in bark crevices on tree trunks, especially during migration. Their unique coloration makes them blend in with their roosting environment. However, some individuals seem to overwinter in buildings, which may allow them to spend the winter in places that would otherwise be too cold for them.


Copulation of tree bats is likely initiated during flight. After mating, tree bats hibernate alone in tree cavities, bark crevices, beneath leaf litter, or in the twilight zone of caves. Gestation typically takes 50–60 days, so that parturition of pups occurs in early summer when insect availability is high. Pups are born breech by presentation, and the mother consumes the placenta  Females typically give birth to two offspring, with an even sex ratio.


Channel catfish are native to the Nearctic, being well distributed in lower Canada and the eastern and northern United States, as well as parts of northern Mexico.  They have also been introduced into some waters of landlocked Europe (Czech Republic and Romania) and parts of Malaysia and almost as many parts of Indonesia.  They thrive in small and large rivers, reservoirs, natural lakes, and ponds. Channel "cats" are cavity nesters, meaning they lay their eggs in crevices, hollows, or debris, to protect them from swift currents.  In Canada, the species is largely, though not exclusively, limited to the Great Lakes watershed from Lake Nipigon southward.


Adult channel catfish, over 45 cm (17.7 in), consume fishes such as yellow perch and sunfish. The diet of adults consists of snails, clams, crustaceans (such as crayfish), snakes, frogs, small fish, insects, aquatic plants, algae, seeds, grains, nuts, and even small birds and small mammals occasionally. Younger channel catfish are more consistently omnivorous, eating a large variety of plants and animals.


A member of the American catfish genus Ictalurus, channel catfish have a top-end size of about 40–50 pounds (18–23 kg). The world record channel catfish weighed 58 pounds, and was taken from the Santee-Cooper Reservoir in South Carolina, on July 7, 1964. Realistically, a channel catfish over 20 lb (9 kg) is a spectacular specimen, and most catfish anglers view a 10-lb (4.5-kg) fish as a very admirable catch.  Furthermore, the average size channel catfish an angler could expect to find in most waterways would be between 2 pounds (1 kg) and 4 pounds (2 kg), and between 12 in (31 cm) and 24 in (61 cm).
Channel catfish often coexist in the same waterways with its close relative, the blue catfish, which is somewhat less common, but tends to grow much larger (with several specimens confirmed to weigh above 100 lb).
As channel catfish grow longer, they increase in weight.  The relationship between length and weight is not linear. The relationship between length (L, in cm) and weight (W, in kg) for nearly all species of fish can be expressed by an equation of the form:
W=(L/L_{1})^{b}\!\,
Invariably, b is close to 3.0 for all species, L_{1} is the length of a typical fish weighing 1 kg. For channel catfish, b = 3.2293, somewhat higher than for many common species, and L_{1}=45.23 cm.


The rhesus macaque (Macaca mulatta), colloquially rhesus monkey, is a species of Old World monkey. There are between six and nine recognised subspecies that are split between two groups, the Chinese-derived and the Indian-derived. Generally brown or grey in colour, it is 47–53 cm (19–21 in) in length with a 20.7–22.9 cm (8.1–9.0 in) tail and weighs 5.3–7.7 kg (12–17 lb). It is native to South, Central, and Southeast Asia and has the widest geographic range of all non-human primates, occupying a great diversity of altitudes and a great variety of habitats, from grasslands to arid and forested areas, but also close to human settlements. Feral colonies are found in the United States, thought to be either released by humans or escapees after hurricanes destroyed zoo and wildlife park facilities.
The rhesus macaque is diurnal, arboreal, and terrestrial. It is mostly herbivorous, mainly eating fruit, but will also consume seeds, roots, buds, bark, and cereals. Studies show almost 100 different plant species in its diet. It will also eat invertebrates, drink water from streams and rivers, and has specialised cheek pouches where it can temporarily store food.
Like other macaques, the rhesus macaque is gregarious with troops comprising 20-200 individuals. The social groups are matrilineal, whereby a female's rank is decided by the rank of her mother. There has been extensive research into female philopatry, common in social animals, as females tend not to leave social group. It communicates with a variety of facial expressions, vocalisations, body postures, and gestures. Facial expressions are used to appease or redirect aggression, assert dominance, and threaten other individuals and vocalisations may be made to elicit grooming, while moving, or in threatening situations. It spends most of its day feeding and resting, the rest is occupied with travelling, grooming, and playing.
Due to its relatively easy upkeep, wide availability, and closeness to humans anatomically and physiologically, it has been used extensively in medical and biological research on human and animal health-related topics. It has facilitated many scientific breakthroughs including vaccines for rabies, smallpox, and polio and antiretroviral medication to treat HIV/AIDS. A rhesus macaque became the first primate astronaut in 1948, but died during the flight, followed on 14 June 1949 by Albert II, who became the first primate and first mammal in space. It is listed as Least Concern in the IUCN Red List of Threatened Species in view of its wide distribution, presumed large population, and its tolerance of a broad range of habitats.


Rhesus macaques are native to India, Bangladesh, Pakistan, Nepal, Myanmar, Thailand, Afghanistan, Vietnam, southern China, and some neighboring areas. They have the widest geographic ranges of any non-human primate, occupying a great diversity of altitudes throughout Central, South, and Southeast Asia. Inhabiting arid, open areas, rhesus macaques may be found in grasslands, woodlands, and in mountainous regions up to 2,500 m (8,200 ft) in elevation. They are strong swimmers, and can swim across rivers. Rhesus macaques are noted for their tendency to move from rural to urban areas, coming to rely on handouts or refuse from humans. They adapt well to human presence, and form larger troops in human-dominated landscapes than in forests.
The southern and the northern distributional limits for rhesus and bonnet macaques, respectively, currently run parallel to each other in the western part of India, are separated by a large gap in the center, and converge on the eastern coast of the peninsula to form a distribution overlap zone. This overlap region is characterized by the presence of mixed-species troops, with pure troops of both species sometimes occurring even in close proximity to one another. The range extension of rhesus macaque – a natural process in some areas, and a direct consequence of introduction by humans in other regions – poses grave implications for the endemic and declining populations of bonnet macaques in southern India.


The white perch (Morone americana) is not a true perch but is a fish of the temperate bass family, Moronidae, notable as a food and game fish in eastern North America. In some places it is referred to as "Silver Bass".
The name "White perch" is sometimes applied to the white crappie.
Generally silvery-white in color, hence the name, depending upon habitat and size specimens have begun to develop a darker shade near the dorsal fin and along the top of the fish. This sometimes earns them the nickname "black-back". White perch have been reported up to 49.5 cm (19.5 in) in length and weighing 2.2 kg (4.9 lb).
Although favoring brackish waters, it is also found in fresh water and coastal areas from the St. Lawrence River and Lake Ontario south to the Pee Dee River in South Carolina, and as far east as Nova Scotia.
They are also found in the lower Great Lakes, Finger Lakes, Long Island Sound and nearby coastal areas, Hudson and Mohawk River system, Delaware Bay and Chesapeake Bay. It is also found occasionally in small land-locked lakes and ponds. The raw meat is of a somewhat pinkish hue, but when cooked, it is white and flaky. At times, a parasite known as Lironeca ovalis is located in the gills. They are only known to reduce the growing rate of white perch.


White perch are known to eat the eggs of many species native to the Great Lakes, such as walleye and other true perches. At times, fish eggs are 100% of their diet. They prefer to eat small minnows like mud minnows and fathead minnows. In the Chesapeake Bay, white perch commonly prey upon grass shrimp, razor clams, and bloodworms which are all common to the region.


The French angelfish is found at depths between 3 to 100 m (9.8 to 328.1 ft). It is common on rocky and coral reefs where it is normally encountered in pairs, frequently in the vicinity of sea fans. Its diet comprises sponges, algae, bryozoans, zoantharians, gorgonians, hydroids, coral and tunicates. These pairs are highly territorial, and typically both vigorously defending their territory from their neighbours. Juveniles act as cleaner fish, establishing cleaning stations where they remove ectoparasites and clean a wide range of other fish species. Species recorded as being clients of juvenile French angelfish, include jacks, snappers, morays, grunts, surgeonfishes and wrasses.. When they are trying to draw client fish to the cleaning station the juvenile displays by using a fluttering swimming motion and as it cleans it touches the recipient of its service with its pelvic fins. During the day you will mostly see these fish out and about, but come night they seek shelter in their designated hiding spot where they return every night. They can produce a knocking sound when alarmed.
The pair normally swim a short distance above the reef. There are no obvious courtship displays or clear sexual dimorphism. At dusk, the pair swam upwards in a wide, shallow curve from the substrate, travelling around 7 to 10 m horizontally as they climb to a 2 or 3 m (6 ft 7 in or 9 ft 10 in). As they ascend, both angle their bodies slightly, with their vents very close together, even touching. They hold this posture throughout the zenith of their curve separating as they descend. Neighbouring pairs were observed undertaking  similar movements above the reef at roughly the same time. The observers were unable to ascertain if gametes were released in these displays. Neighbouring pairs were not seen interfering with these displays. This species is a protogynous hermaphrodite, the female can change sex to become a male if no male is present.


The French angelfish is found in the western Atlantic from New York and the Bahamas to Brazil, and also the Gulf of Mexico and the Caribbean, including the Antilles, Roatan, and the eastern Atlantic from around Ascension Island and St. Paul's Rocks.


The French angelfish has a laterally compressed body which is almost circular in shape. The head is deep with a short snout ending in a small mouth which contains numerous bristle-like teeth. There is an obvious spine at the corner of the preoperculum while there are no spines on the operculum or under the eye. The dorsal fin contains 10 spines and 29-31 soft rays while the anal fin contains 3 spines and 22-24 soft rays. This species attains a maximum total length of 41.1 centimetres (16.2 in). The juveniles are almost completely  black apart from five vertical yellow bands the first around  the mouth and the last at the caudal peduncle, the bands on the body are curved. The caudal fin has yellow margins. The adults are also mainly black but most of the scales on the body have a golden-yellow edge. They have a white mouth and a yellow orbit. The pectoral fins have a wide orange-yellow band and the dorsal fin has a long yellow filamentous extension growing from its soft-rayed part.


Harbor seals prefer to frequent familiar resting sites. They may spend several days at sea and travel up to 50 km in search of feeding grounds, and will also swim more than a hundred miles upstream into fresh water in large rivers in search of migratory fish like shad and likely salmon. Resting sites may be both rugged, rocky coasts, such as those of the Hebrides or the shorelines of New England, or sandy beaches, like the ones that flank Normandy in Northern France or the Outer Banks of North Carolina. Harbor seals frequently congregate in harbors, bays, sandy intertidal zones, and estuaries in pursuit of prey fish such as salmon, menhaden, anchovy, sea bass, herring, mackerel, cod, whiting and flatfish, and occasionally shrimp, crabs, mollusks, and squid. Atlantic subspecies of either Europe or North America also exploit deeper-dwelling fish of the genus Ammodytes as a food source and Pacific subspecies have been recorded occasionally consuming fish of the genus Oncorhynchus. Although primarily coastal, dives of over 500 m have been recorded.  Harbor seals have been recorded to attack, kill and eat several kinds of ducks.


The California population of subspecies P. v. richardsi amounted to about 25,000 individuals as of 1984. Pacific harbor seals or California harbor seals are found along the entire Pacific Coast shoreline of the state. They prefer to remain relatively close to shore in subtidal and intertidal zones, and have not been seen beyond the Channel Islands as a pelagic form; moreover, they often venture into bays and estuaries and even swim up coastal rivers. They feed in shallow littoral waters on herring, flounder, hake, anchovy, codfish, and sculpin.
Breeding occurs in California from March to May, with pupping between April and May, depending on local populations. As top-level feeders in the kelp forest, harbor seals enhance species diversity and productivity. They are preyed upon by killer whales (orcas) and white sharks. Haul out sites in California include urban beaches and from time to time they can be seen having a nap on the beach in all of San Francisco Bay, which would include the conurbation of Richmond, Oakland, and San Francisco, the Greater Los Angeles area, which would include Santa Barbara, the city of Los Angeles itself, and Long Beach, and all of San Diego Bay, most famously beaches near La Jolla.
Considerable scientific inquiry has been carried out by the Marine Mammal Center and other research organizations beginning in the 1980s regarding the incidence and transmission of diseases in harbor seals in the wild, including analysis of phocine herpesvirus. In  San Francisco Bay, some harbor seals are fully or partially reddish in color, possibly caused by an accumulation of trace elements such as iron or selenium in the ocean, or a change in the hair follicles.
Although some of the largest harbor seal pupping areas are found in California, they are also found north along the Pacific Coast in Oregon, Washington, British Columbia and Alaska. Large populations move with the season south along the west coast of Canada and may winter on the islands in Washington and Oregon. Pupping is known to occur in both Washington and Oregon as of 2020. People are advised to stay at least 50m away from harbor seals that have hauled out on land, especially the pups, as mothers will abandon them if there's too much human activity nearby.


Harbor seals are solitary, but are gregarious when hauled out and during the breeding season, though they do not form groups as large as some other seals. When not actively feeding, they haul to rest. They tend to be coastal, not venturing more than 20 km offshore. The mating system is not known, but thought to be polygamous. Females give birth once per year, with a gestation period around nine months. Females have a mean age at sexual maturity of 3.72 years and a mean age at first parturition of 4.64. Both courtship and mating occur under water. Researchers have found males gather under water, turn on their backs, put their heads together, and vocalize to attract females ready for breeding. Pregnancy rate of females was 92% from age 3 to age 36, with lowered reproductive success after the age of 25 years.
Birthing of pups occurs annually on shore. The timing of the pupping season varies with location, occurring in February for populations in lower latitudes, and as late as July in the subarctic zone. The mothers are the sole providers of care, with lactation lasting 24 days. The single pups are born well developed, capable of swimming and diving within hours. Suckling for three to four weeks, pups feed on the mother's rich, fatty milk and grow rapidly; born weighing up to 16 kilograms, the pups may double their weight by the time of weaning.
Harbor seals must spend a great deal of time on shore when molting, which occurs shortly after breeding. This onshore time is important to the life cycle, and can be disturbed when substantial human presence occurs. The timing of onset of molt depends on the age and sex of the animal, with yearlings molting first and adult males last. A female mates again immediately following the weaning of her pup.  Harbor seals are sometimes reluctant to haul out in the presence of humans, so shoreline development and access must be carefully studied in known locations of seal haul out.
In comparison to many pinniped species, and in contrast to otariid pinnipeds, harbor seals are generally regarded to be more vocally reticent. However, they do utilize non-harmonic vocalizations to maintain breeding territories and to attract mates during specified times of year, and also during mother and pup interactions.
Annual survival rates were calculated at 0.91 for adult males, and 0.902 for adult females. Maximum age for females was 36 and for males 31 years.


The harbor (or harbour) seal (Phoca vitulina), also known as the common seal, is a true seal found along temperate and Arctic marine coastlines of the Northern Hemisphere. The most widely distributed species of pinniped (walruses, eared seals, and true seals), they are found in coastal waters of the northern Atlantic, Pacific Oceans, Baltic and North Seas.
Harbor seals are brown, silvery white, tan, or gray, with distinctive V-shaped nostrils. An adult can attain a length of 1.85 m (6.1 ft) and a mass of up to 168 kg (370 lb). Blubber under the seal's skin helps to maintain body temperature. Females outlive males (30–35 years versus 20–25 years). Harbor seals stick to familiar resting spots or haulout sites, generally rocky areas (although ice, sand, and mud may also be used) where they are protected from adverse weather conditions and predation, near a foraging area. Males may fight over mates under water and on land. Females bear a single pup after a nine-month gestation, which they care for alone. Pups can weigh up to 16 kg (35 lb) and are able to swim and dive within hours of birth. They develop quickly on their mothers' fat-rich milk, and are weaned after four to six weeks.
The global population of harbor seals is 350,000–500,000, but the freshwater subspecies Ungava Seal in Northern Quebec is endangered. Once a common practice, sealing is now illegal in many nations within the animal's range.


While primarily an insectivore, the striped skunk is adaptable enough to incorporate other animals and even vegetable matter into its diet. The most frequently consumed insects include grasshoppers, beetles, crickets, caterpillars, other insect larvae and bees. Other invertebrates may include worms, crayfish and other non-insect arthropods. In the winter and spring months, the striped skunk will supplement its diet with vertebrates such as white-footed mice, voles, eggs and the chicks of ground nesting birds.  The striped skunk is also known to consume amphibians, reptiles, carrion and fish. Striped skunks inhabiting California's coastal areas will feed on crabs and beached fish. While not adapted for chasing fleet-footed prey, at least one specimen was observed pursuing gray cottontails into their burrows. The skunk will also consume vegetable matter, such as apples, blueberries, black cherries, ground cherries, corn and nightshade when in season.
Striped skunks are known to use their sharp claws to tear apart rotting logs to find grubs, dig in the soil for insects, and pin down prey. Their practice of digging leaves small-but-noticeable pits in the ground, which can provide evidence of their presence in an area.


Because of its formidable defensive capability, the striped skunk has few natural enemies. Mammalian predators typically avoid skunks, unless they are starving. Such predators include cougars, coyotes, bobcats, badgers, and red and gray foxes. Predatory birds, including golden and bald eagles, and great horned owls tend to have greater success in hunting skunks, though they still risk being blinded by their prey's musk.


The striped skunk (Mephitis mephitis) is a skunk of the genus Mephitis that occurs across much of North America, including southern Canada, the United States, and northern Mexico. It is currently listed as least concern by the IUCN on account of its wide range and ability to adapt to human-modified environments.
Striped skunks are polygamous omnivores with few natural predators, save for birds of prey. Like all skunks, they possess highly developed musk-filled scent glands to ward off predators. They have a long history of association with humans, having been trapped and captively bred for their fur and kept as pets. The striped skunk is one of the most recognizable of North America's animals, and is a popular figure in cartoons and children's books.


The striped skunk is polygamous, and normally breeds once a year, though yearling females who have failed to mate may enter a second estrous cycle a month after the first. The mating season usually occurs between mid-February to mid-April, though it is delayed at higher latitudes. Prior to copulating, the males' testicles swell during the January–February period, with maximum size being attained in March. Males during this period will cover much ground in their search for females, sometimes covering 4 km (2.5 mi) per night.
When a male locates a female, he will approach her from the rear and lick her genitals, then bite her on the nape before copulating. A single male may have a harem of several females, which he mates with and defends against other males for a period of about 35 days. Once the mating period has finished, the impregnated females confine themselves to their dens, while the males attempt to rebuild their fat reserves.
The gestation period lasts around 59–77 days, with kits being born at about mid-May to early June. Litters generally consist of 2–12 kits, with the average being five or six, though a litter of 18 is known from Pennsylvania. Kits are born blind and sparsely furred, weighing 25–40 grams. The eyes open after around three weeks, and are weaned after 42–56 days. Although their musk is still undeveloped, kits of this age will instinctively assume the defensive stand position when threatened. At this point, the kits may accompany their mother outside the den, becoming independent after 2½ months.


The striped skunk is a stoutly-built, short-limbed animal with a small, conical head and a long, heavily furred tail. Adult males are 10% larger than females, with both sexes measuring between 52 and 77 cm in total body length and usually weighing 1.8–4.5 kg (4.0–9.9 lb), though some may weigh 5.5 kg (12 lb). The feet are plantigrade with bare soles, and are not as broad or flat as those of hog-nosed skunks. The forefeet are armed with five long, curved claws adapted for digging, while those on the hind feet are shorter and straighter.
The color patterns of the fur vary greatly, but generally consist of a black base with a white stripe extending from the head which divides along the shoulders, continuing along the flanks to the rump and tail. Some specimens have a white patch on the chest, while others bear white stripes on the outer surface of the front limbs. Brown or cream-colored mutations occasionally occur.
Like all skunks, the striped skunk possesses two highly developed scent glands, one on each side of the anus, containing about 15 milliliters of musk each, which provides a chemical defense against predation. This oily, yellow-colored musk consists of a mixture of powerfully odorous thiols (sulfur analogues of alcohols, in older sources called "mercaptans"), which can be sprayed at a distance of several meters. The odor of this musk was likened by Ernest Thompson Seton to a mixture of perfume musk, essence of garlic, burning sulfur and sewer gas "magnified a thousand times", though Clinton Hart Merriam claimed that it isn't "one tenth" as offensive as that produced by minks and weasels. It can be sprayed at a distance of several meters. If sprayed on the eyes, this compound can cause a temporary burning sensation.


American bison live in river valleys, and on prairies and plains.  Typical habitat is open or semiopen grasslands, as well as sagebrush, semiarid lands, and scrublands. Some lightly wooded areas are also known historically to have supported bison.  Bison also graze in hilly or mountainous areas where the slopes are not steep.  Though not particularly known as high-altitude animals, bison in the Yellowstone Park bison herd are frequently found at elevations above 2,400 m (8,000 ft) and the Henry Mountains bison herd is found on the plains around the Henry Mountains, Utah, as well as in mountain valleys of the Henry Mountains to an altitude of 3,000 m (10,000 ft).
Those in Yukon, Canada, typically summer in alpine plateaus above treeline. The first thoroughfares of North America, except for the time-obliterated paths of mastodon or muskox and the routes of the mound builders, were the traces made by bison and deer in seasonal migration and between feeding grounds and salt licks. Many of these routes, hammered by countless hoofs instinctively following watersheds and the crests of ridges in avoidance of lower places' summer muck and winter snowdrifts, were followed by the aboriginal North Americans as courses to hunting grounds and as warriors' paths. They were invaluable to explorers and were adopted by pioneers.
Bison traces were characteristically north and south, but several key east–west trails were used later as railways. Some of these include the Cumberland Gap through the Blue Ridge Mountains to upper Kentucky. A heavily used trace crossed the Ohio River at the Falls of the Ohio and ran west, crossing the Wabash River near Vincennes, Indiana. In Senator Thomas Hart Benton's phrase saluting these sagacious path-makers, the bison paved the way for the railroads to the Pacific.


While often secure from predation because of their size and strength, in some areas, vulnerable individuals are regularly preyed upon by wolves. Wolf predation typically peaks in late winter, when elk migrates south and bison are distressed with heavy snows and shortages of food sources, with attacks usually being concentrated on weakened and injured cows and calves. Wolves more actively target herds with calves than those without. The length of a predation episode varies, ranging from a few minutes to over nine hours. Bison display five apparent defense strategies in protecting calves from wolves: running to a cow; running to a herd; running to the nearest bull; running in the front or center of a stampeding herd; entering water bodies, such as lakes or rivers. When fleeing wolves in open areas, cows with young calves take the lead, while bulls take to the rear of the herds, to guard the cows' escape. Bison typically ignore wolves not displaying hunting behavior. Wolf packs specializing in bison tend to have more males, because their larger size than females allows them to wrestle prey to the ground more effectively. Healthy, mature bulls in herds rarely fall prey.
Grizzly bears are known to feed on carcass and may steal wolves' kills. While grizzlies can also pose a threat to calves and sometimes old, injured, or sick adult bison, direct killing of non-calves is rare even when targeting lone and injured young individuals; attacking healthy bison is risky for bears, who can be killed instead.