The Giant Moray Eel lives in the Indo-Pacific region's rocky seafloors and coral reefs. It is the world's largest moray eel, measuring 10 feet and weighing over 66 pounds. (The Slender Giant Moray Eel is longer.) Its brown skin has a unique dark spot pattern contrasting with the colorful reefs.

Moreover, this nocturnal eel hides in crevices and caves to avoid predators and rest for its nighttime hunts for fish, cephalopods, and crustaceans. 

The Giant Moray Eel also forms alliances with coral groupers to hunt prey. It chases prey into open waters while the grouper takes advantage.

The California Moray Eel lives in the moonlit kelp forests of the eastern Pacific. Their color palette ranges from bronze to olive green and can grow up to 60 in long, although most average around 24 in. Despite their size, they are shy and spend their days hidden in rocky alcoves, away from other marine life.

At nightfall, the California Moray Eel becomes active and relies on its sense of smell to locate small fish or various invertebrates. It creates a cloud of slime to trap and paralyze its victim against the reef or kelp.

Additionally, the eel starts life as a female and becomes a male as it matures through a phenomenon called protogyny. 

The California Moray is a primarily solitary species that mainly interacts with others during mating.

The Longfin African conger lives in the Indo-Pacific oceans, from the Red Sea and East Africa to the Marquesas and Easter Islands. They can survive depths of 262 feet, growing up to 4.3 feet long.

This type of eel feeds on small fish and crustaceans. It has an elongated body and fin extending from just behind the head to the tip of the tail, earning it the name 'Longfin.'

The Snowflake Moray Eel has a distinctive pattern of black splotches resembling snowflakes. It is a relatively small eel, typically up to 24 inches long. They live in the tropical Indo-Pacific region, among coral reefs and rock formations in warm summer waters.

The nocturnal Snowflake Moray Eel spends the day in reef crevices to avoid the sun. It is skilled enough to navigate its underwater labyrinth and hunt for food at night. Moreover, its long, flexible body allows it to probe into narrow corners and crevices, looking for small fish and crustaceans.

The Snowflake Moray Eel is peaceful when not on the hunt, attracting aquarium owners worldwide.

The Green Moray Eel inhabits the deep, shadowy waters of the western Atlantic Ocean. Green Moray Eels can grow up to 7.2 feet long and weigh approximately 64 lbs.

Despite its name, this species is not green, but its natural color is soft brown with a layer of yellow mucus. When hit by light, this mucus gives the appearance of vibrant green. 

These types of eels periodically open and close their mouths because their gills require a continuous flow of water for breathing. They eat mainly fish, squids, and crabs. Lastly, they hide in dark crevices of coral reefs or rocky underwater terrains during the day and come out at night to hunt.

American Crows are approximately 16-21 inches long, showcasing an iridescent, uniform black color. These daring birds in North America adapt comfortably to open habitats, flourishing in farmlands, forests, and cities.

Their diets are notably diverse, scavenging on grains, fruits, insects, small animals, carrion, and human food waste. Scientists have also observed them modifying wood and using it to probe a small hole where a spider lives.

Regarding parenting, the Corvidae family is practicing cooperative breeding. In the 1980s, Lawrence Kilham first observed adult and yearling American Crows take turns in parenting. Young crows can stay with their parents for five years or longer1.

Moreover, the West Nile Virus has impacted their numbers by 45% since 1999. Fortunately, thanks to their resilience, they are still a species of least concern.

The Northwestern Crow stands around 17 inches tall, slightly smaller than the common crow. This type of crow nests primarily along the coasts of the northeastern Pacific Ocean, predominantly in forested areas near rivers.

Interestingly, the diet of this coastal crow differs slightly from that of its relatives. Aside from the typical crow menu, it forages along the shoreline to feed on clams, crustaceans, and sea urchins, employing different tactics to open them up.

The Hooded Crow or Scald Crow showcases a combination of grey and black body coloring. On average, this crow grows up to 20 inches in length. 

It's often spotted in northern and eastern Europe and parts of the Middle East. They display a preference for woodland, farmland, and urban areas. Like the Carrion Crow, they are constantly scavenging but feed on mollusks, small mammals, nuts, etc.

The Collared Crow, distinguished by the white collar marking on its neck and chest, is significantly larger than most crow species, usually measuring up to 22 inches long. 

Typically found in China and Vietnam, the Collared Crow thrives in open habitats such as fields and wetlands. Its diet mainly consists of grains, seeds, insects, mollusks, and occasionally easily accessible eggs and carrion when food is scarce. 

In 2018, IUCN declared them as vulnerable species because of agricultural intensification that kills most of their prey and direct persecution by humans2.

The White-necked Crow is distinguished by its black plumage, except for a patch of white stretching from its throat to its chest. The lighter hue is hidden since it only occurs on the base of their neck feathers, which are rarely seen.

Roughly the size of a small raven, it measures about 17 to 18 inches long. It boasts a large, slightly curved bill and red iris. 

This species primarily dwells in forests and woodlands across specific regions of the Caribbean, notably Haiti and the Dominican Republic. Due to agricultural conversion, hunting, and pest control, this type of crow is already extinct in Puerto Rico. Overall, White-necked Crows are considered vulnerable species by the IUCN.