The California condor is a large terrestrial vulture in the family Cathartidae, with a wingspan of 2.7–3.2 m, black plumage and a bare head and neck. It inhabits coastal cliffs and arid canyons, feeding mainly on carrion of large mammals. Pairs nest on cliff ledges, laying one egg every other year.

The carrion crow is a 44–51 cm corvid, all black with a stout bill and strong flight. It inhabits urban areas, farmland and open woodlands across Europe and Asia, feeding on insects, small vertebrates, seeds and carrion, and scavenging human refuse. An opportunistic omnivore, it uses tools and caches food. During the breeding season (March–May), pairs defend a territory, build a large branch nest and raise 3–5 young.

The Coyote is a medium-sized canine, very similar to the wolf but smaller and more agile. Its fur varies from gray to light brown, with a face often marked by black traits, a white chest and belly, and dark legs. The Coyote is easily recognizable by its pointed muzzle, relatively large ears, and bushy tail. It typically stands between 60 and 80 cm at the shoulder, with a total length of 75 to 90 cm for the body, excluding the tail. This canine is an opportunistic feeder, primarily hunting small mammals such as rodents, rabbits, and sometimes birds, but it can also eat fruits and carrion. Highly adaptable, the Coyote inhabits a wide variety of environments, ranging from prairies and deserts to urban areas, and it is particularly active at dusk and during the night. Unlike other predators, the Coyote often hunts alone or in small groups. Although its population is stable across much of its range, it is sometimes seen as a nuisance in certain areas and faces threats from hunting and habitat loss.

The cane toad (Rhinella marina) is a robust amphibian reaching up to 23 cm in total length, with a stocky body covered in rough, warty skin colored olive to deep brown. Native to tropical wetlands of Central and South America, it inhabits marshes, rice fields, slow-flowing streams and roadside ditches, preying on insects, spiders and small vertebrates. An invasive species introduced across multiple continents, it secretes potent skin toxins to deter predators. Males vocalize in resonant choruses during the rainy season. Breeding occurs in large communal pools, where females deposit thousands of eggs in gelatinous strings that hatch in two to five days. After hatching, tadpoles metamorphose rapidly and juveniles may live over ten years.

The Common Spadefoot, scientifically known as Pelobates fuscus, is a discreet and fascinating amphibian. It is characterized by its smooth skin and brownish coloration, often speckled with dark spots. This toad has powerful hind legs adapted for digging into the soil, allowing it to quickly burrow when threatened. Primarily nocturnal, it emerges from its burrow to feed on insects and other small invertebrates. Its natural habitat includes sandy areas and wet meadows, providing ideal conditions for reproduction. Although its population is stable, it is sensitive to habitat destruction and water pollution.

The common toad is a sturdy terrestrial amphibian of 8–13 cm with a warty olive-brown back and a yellowish spotted belly. It inhabits damp meadows, open woodland edges and gardens, feeding on insects, spiders and worms captured on the ground. During the breeding season, males emit a low, croaking call from the water’s surface to attract females, which lay strings of eggs in double rows.

The Bufo alvarius, commonly known as the Colorado River Toad, is a fascinating species of toad found primarily in the arid regions of the southwestern United States and northern Mexico. This toad is particularly known for its large size, reaching up to 19 cm in length, and its smooth, moist skin, often speckled with dark spots. It is famous for the toxic secretions it produces, containing bufotenin, a psychoactive substance. These secretions are used by some predators as a means of defense. The Bufo alvarius is a nocturnal animal, preferring the cool hours of the night to hunt its prey, mainly insects and small invertebrates.

The Suriname Toad is a fascinating amphibian species, known for its unique appearance and extraordinary reproductive behavior. This flat and wide toad is often called the 'birthing toad' because of the way it carries its eggs on its back, where the tadpoles develop until they are ready to hatch. It primarily lives in slow-moving waters and swamps in the tropical forests of South America, particularly in Colombia, Venezuela, Suriname, and Guyana. Its flat body allows it to hide easily in aquatic substrate, and it is primarily nocturnal. Its skin is a brownish-green, and its appearance allows it to blend perfectly into its aquatic environment.

The cane toad, or Bufo marinus, is a large amphibian native to Central and South America. It can grow up to 24 cm in length and weigh over 1 kg. Its skin is rough and covered with glands that secrete a potent toxin used for defense against predators. This nocturnal toad primarily feeds on insects but can also consume small animals. Introduced in several regions to control agricultural pests, it has become an invasive species, notably in Australia, where it has caused ecological imbalances. Its ability to adapt to various environments makes it a fascinating subject of study for biologists.

The Cuban crocodile, Crocodylus rhombifer, is a medium-sized species endemic to Cuba, primarily found in the Zapata Swamp and the Isle of Youth. It typically measures between 2 and 3.5 meters in length and is known for its distinctive scaly skin with vibrant colors ranging from olive green to yellow, with black patterns. This opportunistic predator feeds mainly on fish, small mammals, and birds. It is recognized for its aggressive and territorial behavior, making it potentially dangerous to humans. Unfortunately, this species is critically endangered due to habitat loss and illegal hunting.

The Cottonmouth, or Agkistrodon piscivorus, is a venomous semi-aquatic snake found primarily in the southeastern United States. It is recognizable by its triangular head and coloration that ranges from brown to black, often with lighter crossbands. This snake is well adapted to aquatic environments such as swamps, rivers, and lakes, but can also be found on land. It is known for its defensive behavior, widely opening its mouth to show the white interior, hence the name "cottonmouth". Although venomous, it generally only attacks if it feels threatened. Its bite can be dangerous to humans, requiring immediate medical attention.

The Common Dolphin is a medium-sized cetacean, easily recognizable by its streamlined body and distinctive beak. It typically measures between 2 and 2.5 meters in length and weighs between 100 and 150 kg. This dolphin is widely distributed in temperate and tropical waters, particularly in the Mediterranean, the Atlantic, and the seas around Asia. The Common Dolphin primarily feeds on fish, cephalopods, and sometimes small crustaceans, hunting in highly coordinated groups. Its social structure is complex, with groups ranging from a few individuals to several hundred, depending on environmental conditions and the availability of food resources. It is also known for its acrobatic behaviors, such as jumping and group play, and is often seen following boats. While this species is not currently endangered, it faces threats from pollution, disturbances caused by human activities at sea, and bycatch in fishing nets.

The common duiker, or Sylvicapra grimmia, is a small African antelope found in various regions across the continent. It is characterized by its modest size, reaching about 50 cm at the shoulder, and its grayish-brown coat that allows it to blend into its surroundings. Males have small, straight horns, while females are hornless. This animal is primarily solitary, although it can sometimes be seen in small family groups. It is highly adaptable, living in diverse habitats ranging from savannas to sparse forests. The duiker is an opportunistic herbivore, feeding on leaves, fruits, and sometimes bark. Its ability to survive in varied environments makes it a resilient species.

The Eider Duck is a large sea duck, easily recognized by its distinctive plumage. The adult male has a white body with a black head and neck, while the female is more muted with a brown speckled plumage. The Eider measures about 55 to 70 cm in length, with a wingspan of 100 to 125 cm, and weighs between 1.5 and 2.5 kg. It is primarily found in coastal regions of the North Atlantic, notably in Northern Europe, Canada, and Alaska. This duck primarily feeds on mollusks, crustaceans, and small fish, which it finds by diving underwater. It is also known for its social behavior, often living in large colonies during the breeding season. The Eider Duck is particularly famous for its down, a soft and insulating material harvested from the female's nests after laying, used to make luxury duvets and pillows. While the species is not immediately endangered, it is threatened by marine pollution, habitat loss due to coastal urbanization, and hunting.

The Common Eland is a large herbivorous ungulate, belonging to the bovidae family, and one of the largest species of antelope. It can stand up to 1.5 meters tall at the withers and weigh between 400 and 900 kg, with males generally being larger than females. Its coat is usually light brown or gray, with lighter vertical stripes on the flanks. The Common Eland has large, spiral horns that can reach up to 80 cm in males. It primarily inhabits savannas and grasslands in sub-Saharan Africa, where it feeds mainly on grasses, leaves, and bushes. It is a social animal, living in large groups, especially during the breeding season. While the Common Eland is currently listed as of least concern, it faces threats such as habitat loss, hunting, and competition with livestock for food resources.

The Chestnut-cheeked Starling, scientifically known as Sturnia philippensis, is a medium-sized bird belonging to the Sturnidae family. It is easily identifiable by its silvery-grey plumage and distinctive chestnut cheeks. This bird is primarily arboreal, feeding on fruits, insects, and nectar. It inhabits tropical and subtropical forests, as well as agricultural areas and gardens. Known for its varied and melodious vocalizations, the Chestnut-cheeked Starling is currently classified as "Least Concern" by the IUCN, although deforestation and habitat loss pose potential threats. This sociable bird is often seen in small flocks.

The Common Pheasant, or Colchian Pheasant, is a medium to large-sized bird, easily recognizable by its bright colors and silky plumage. The adult male is particularly spectacular, with shiny plumage in shades of green, red, gold, and blue, and a long tail adorned with fine feathers. It measures about 70 cm in length, most of which is its tail, and weighs between 0.8 and 1.5 kg. The female, more discreet, has brown spotted plumage that helps her blend into her surroundings. Native to Asia Minor and the Caucasus region, the Colchian Pheasant has been introduced to many parts of the world for hunting and decoration. It typically inhabits wooded areas, cultivated fields, and grasslands. Its diet is omnivorous, consisting of seeds, berries, insects, and sometimes small vertebrates. The species is mainly active at dawn and dusk. While the Common Pheasant is not threatened, it faces risks such as habitat loss, excessive hunting, and predation by carnivores.

The common moorhen is an aquatic bird easily recognized by its black plumage, bright red beak, and white frontal shield. It is primarily found in wetlands, lakes, and marshes across Europe, Asia, and North Africa. The common moorhen is omnivorous, feeding on aquatic plants, insects, and small fish. It is also known for its territorial behavior and quick flights when disturbed.

The Common Pochard is a medium-sized diving duck, measuring between 42 and 49 cm in length. The male has a reddish-brown head, black breast, and light grey body, while the female displays a more subdued brown-grey plumage. This species inhabits lakes, ponds, and slow-flowing rivers rich in aquatic vegetation. It feeds mainly on aquatic plants but also consumes invertebrates. The Common Pochard is migratory, breeding in Europe and Asia, and wintering further south. It is currently classified as vulnerable due to population declines, primarily caused by habitat loss and pollution.

The Common Goldeneye is a medium-sized diving duck, measuring about 42 to 50 cm in length. The breeding male has a glossy dark green head, a distinct white spot below the eye, and a bright yellow eye. The female is brown with a chocolate-colored head and a subtle white collar. It inhabits lakes, slow rivers, and coastal bays in Europe, Asia, and North America. A migratory species, it nests in tree cavities or artificial nest boxes. Its diet includes mollusks, crustaceans, aquatic insects, and small fish. Though generally of Least Concern, it may be impacted locally by the loss of natural nesting sites.

The Cuvier's gazelle is a species of gazelle native to North Africa, mainly found in Algeria, Tunisia, and Morocco. It is characterized by its medium size, lyre-shaped horns, and light brown coat with white markings on the belly and legs. Adapted to arid environments, it inhabits steppes, mountains, and semi-desert areas. It is herbivorous, feeding mainly on grasses and leaves. The Cuvier's gazelle is an endangered species, primarily due to excessive hunting and habitat loss. Conservation efforts are underway to protect this iconic species of North African wildlife.

The Common Genet is a small, agile, and elegant carnivore, easily recognizable by its long and slender body, as well as its characteristic spots. It measures between 45 and 60 cm in length, with a tail measuring 40 to 50 cm, and typically weighs between 1.5 and 2.5 kg. Its coat is usually light gray or brown, speckled with dark spots that form a distinctive pattern on its back and flanks. The Common Genet has a bushy tail and a body shape that allows it to easily climb trees and slip into narrow spaces. It primarily inhabits forests, woodlands, and wooded areas in North and South Africa, as well as the Iberian Peninsula. This carnivore is omnivorous, feeding mainly on small mammals, birds, insects, fruits, and berries. The Common Genet is also an excellent climber, often seen moving through trees in search of food or to escape danger. While the Genet is not currently threatened, it faces threats related to habitat loss and human persecution.

The common gull, or Larus canus, is a medium-sized seabird, identifiable by its light grey back and white underparts. Its wings feature a black band with distinctive white spots. The bill is yellow with a greenish tip, and its legs range from green to yellow. It inhabits coasts, lakes, and rivers, often in colonies. An opportunistic feeder, it consumes fish, invertebrates, and human waste. Partially migratory, it moves southward in winter. Its population is stable, though sensitive to environmental changes. The common gull is a social bird, often seen in groups, playing a crucial role in coastal ecosystems.

The common raven is an impressive bird found in mountains, forests, and open areas across Europe, Asia, and North America. It is easily recognized by its large size, glossy black plumage, and hoarse call. This corvid is known for its exceptional intelligence and complex social behavior. It primarily feeds on carcasses, insects, and sometimes fruits and seeds.

The Ringed Plover is a small coastal bird, easily recognizable by its compact size and distinctive plumage. It measures about 20 to 23 cm in length, with a wingspan of 40 to 45 cm, and weighs between 40 and 60 g. Its plumage is mainly beige and white, with black markings on its head and chest, and a distinctive black band around its eyes. The Ringed Plover is a migratory bird, primarily found on beaches, shorelines, and mudflats, where it feeds on small invertebrates, such as worms, crustaceans, and insects. It is often seen running quickly on the sand, searching for food, then stopping abruptly to catch it. The Ringed Plover lives in colonies during the breeding season, but generally prefers to remain alone or in small groups. Although it is not currently endangered, the Ringed Plover is vulnerable to human disturbances, such as the loss of its coastal habitat and the impact of pollution.

The Common Crane is a large migratory bird, easily recognizable by its slender silhouette, long neck, and extended wings. It stands about 1.2 meters tall, with a wingspan of 2 to 2.5 meters, and weighs between 4 and 6 kg. Its plumage is mainly gray, with white markings on the head, neck, and wings. It has a red head and a small tuft of feathers on top, giving it a distinctive appearance. The Common Crane primarily inhabits wetlands, marshes, and lakes across Europe and Asia, with large populations in Scandinavia, Germany, Poland, and the Mediterranean Basin. It is a migratory bird that travels to southern Europe and Africa for the winter. It feeds mainly on plants, roots, seeds, and occasionally insects. The Common Crane is also known for its impressive group migrations, with thousands of individuals flying in a "V" formation. While the species is not endangered, it is vulnerable to the loss of its natural habitat and disruption of its breeding sites.

The Crowned Crane is a large crane species, easily recognizable by its majestic golden plume crown on its head. It stands about 1 meter tall, with a wingspan of 1.8 to 2.2 meters, and weighs between 3 and 5 kg. Its plumage is mainly light gray, with white feathers on its belly and wings, and a head adorned with a golden crest, giving it a royal appearance. This species is primarily found in East Africa, notably in Uganda, Kenya, and Tanzania, where it inhabits wetlands, marshes, and grasslands. The Crowned Crane primarily feeds on seeds, roots, insects, and occasionally small vertebrates. It is a social bird, living in groups and often performing spectacular courtship displays, during which it engages in dances and calls. Although the Crowned Crane is considered "vulnerable," conservation efforts have been implemented to protect the species, as it faces threats from habitat loss, hunting, and human disturbance.

The Cheetah is a large feline known for its exceptional speed, making it the fastest land mammal. It measures about 1.1 to 1.5 meters in length, with a shoulder height of around 75 cm, and weighs between 40 and 65 kg. Its coat is short, golden to light brown with distinct black spots, allowing it to blend effectively in the savannas. It has a round head with large nostrils, sharp eyes, and distinctive black tear marks on its cheeks, which help it focus its vision while hunting. The Cheetah primarily inhabits sub-Saharan Africa, with small populations in Iran, in open habitats such as savannas, grasslands, and deserts. Carnivorous, it mainly feeds on gazelles, springboks, and other small animals. Unlike other large cats, the Cheetah hunts using speed rather than brute strength. It can reach speeds of 100 to 110 km/h in a few seconds, but this speed can only be maintained for short distances. Although the Cheetah is not critically endangered, it faces threats like habitat loss, poaching, and reduced natural prey.

The Common Guillemot is a seabird characterized by its black and white plumage, and its streamlined body which allows it to swim with agility. It measures about 40 to 45 cm in length and weighs between 500 and 700 g. Its head is black with sharp white eyes, and its wings are short and pointed, suited for diving. The Common Guillemot primarily lives on coastal cliffs, where it nests in very dense colonies, often on inaccessible sites. It is found mainly in Northern Europe, particularly in Scandinavia, the United Kingdom, and Iceland, but also along the coasts of the North Atlantic. The Common Guillemot is an excellent diver, primarily feeding on fish, particularly small herring and capelin, which it catches by diving underwater in search of prey. While the species is not endangered, it is vulnerable to marine pollution, climate change, and disruption of its breeding sites.

The Common Merganser is a large diving duck measuring between 58 and 71 cm in length, with a wingspan of 82 to 97 cm. The male features a dark green iridescent head, white body, and black back, while the female has a reddish-brown crested head and light gray body. This duck is characterized by its long, slender red bill with serrated edges, ideal for catching slippery fish. It inhabits clear-water rivers and lakes in forested regions of Europe, Asia, and North America. Nesting in tree cavities or cliff crevices, it lays between 6 and 17 eggs per season. Its diet mainly consists of fish, but also includes amphibians, crustaceans, and aquatic insects. Although listed as Least Concern, habitat loss can locally impact its populations.