Harpy Eagle (Harpia harpyja)

• Type: Bird
• Family: Accipitridae
• Habitat: Tropical rainforest
• Location: Central and South America, from Southern Mexico to Northern Argentinia, though rare in their northern range
• Diet: Arboreal mammals, monkeys, sloths, porcupines, opossums, reptiles, and large birds
• Average lifespan in the wild: 30-50 years
• Size: Length 35-41.3 in (89-105 cm); wingspan 6.5 ft (1.98 m)
• Weight: 16.8-19.8 lbs (7.6-9 kg) for females; 8.8-10.6 lbs (4-4.8 kg) for males

Harpy eagles hunt during the day, and their prey includes monkeys, sloths, porcupines, and other forest mammals. Because they do most of their hunting in the rainforest canopy, they also prey on iguanas, snakes, and large parrots. When in pursuit of a meal, harpy eagles can reach speeds of up to 50 miles per hour. This powerful hunter only eats freshly caught meat, and it brings its catch back to the nest to share with its mate and offspring. If the catch is too big to carry back to the nest, a harpy will eat what it can at the capture spot and bring home the more manageable leftovers. Harpy eagles are known to hunt creatures as large as themselves, and sometimes even larger.

Like all eagles, the harpy has evolved extraordinary eyesight. Eagle eyes are enormous, taking up a large portion of their skull. They are almost too large to move side-to-side with only their eye muscles, so instead the eagle rotates its head (up to 270˚) as it scans the horizon for prey. This frequent head movement may seem like a burden, but its fixed eyes actually allow the eagle’s vision to be more precise. Because their eye muscles barely move, eagles can focus on small and far away objects.

Harpy eagles prefer to roost in prominent trees, especially silk-cotton trees, and they make their nests 90-140 ft above the forest floor. Nests, which can measure up to five feet across, are built from sticks and lined with softer materials like green leaves and seedpods. Some offspring return as adults to the same trees in which they were reared to build their own nests.

The harpy eagle has an incubation period of 56 days. Harpy eagles are monogamous and breed every other year. The female may lay a clutch of two eggs, but will only incubate the first, and the pair will only rear one offspring.

Harpy eagles were once common from Southern Mexico to Northern Argentinia, but deforestation, poaching, and loss of habitat has taken its toll on the species. These magnificent birds are now listed as near threatened. They are increasingly rare in the northern range of their habitat and can no longer be found in many areas where they once lived. With only one offspring being produced every two or three years it is very difficult for harpy eagle populations to bounce back.

Breeding and reintroduction programs have been set up in both Panama and Belize to increase wild harpy eagle populations. At the Neotropical Raptor Center (NRC) in Panama, crews from the Peregrine Fund have found success increasing numbers of harpy eagle offspring by fooling the eagles into laying more than one clutch per breeding seasons. When a clutch is laid, the eggs are left under the female for 12-18 days of natural incubation. At that time, the crew removes the eggs from the nest and places them in artificial incubation, where the eggs will develop and hatch. The removal of the eggs prompts the eagle pair to lay another clutch or two during the same breeding season.  In nature, a harpy eagle pair produces only one chick each year. In the Peregrine Fund’s successful program, a single pair of harpy eagles may produce as many as six fertile eggs in a season.

Did you know: Harpy eagle talons are as large as grizzly bear claws.

Photo by www.birdphotos.com

Canadian Lynx (Lynx canadensis)

• Type: Mammal
• Family: Felidae
• Habitat: Dense forests, rocky areas, and tundra
• Location: Across Canada and Alaska and into some parts of the northern United States
• Diet: Small mammals, mainly snowshoe hares and rodents, but also fish, birds, and deer
• Average lifespan in the wild: 10-20 years
• Size: Length 27 to 43 in (70 to 110 cm); tail 2-6 in (5-16 cm)
• Weight: 11 to 37 lbs (5-17 kg)

Many animals hibernate or migrate to warmer climates in winter, but Canadian lynx are specially adapted to endure cold weather. In addition to a thick winter coat, the lynx has wide, padded, furry paws that work like snowshoes to help the big cat survive winter’s difficult conditions. The Canadian lynx is probably descended from its Eurasian counterpart, which lives in Europe and Siberia. Most likely, ancestors of the modern Canadian lynx migrated across a land bridge during a glacial period, and adapted to their new habitat. The Eurasian lynx is similar in appearance to the Canadian lynx, but nearly twice the size, and mainly hunts large ungulates. Canadian lynx are much better adapted for hunting smaller prey like rabbits.

In fact, snowshoe hares are the main source of prey for Canadian lynx. The population dynamics of Canadian lynx are actually linked to snowshoe hare population cycles, which boom every ten years. A year or two after snowshoe hare populations reach their highest numbers, so do the populations of Canadian lynx. The same is true with lulls—when snowshoe hares are less plentiful, Canadian lynx populations shrink.

Like all cats, the Canadian lynx has exceptional night vision, thanks to a layer of mirror-like cells in their eyes called the tapetum lucidum. Light that is unabsorbed by the retinal receptor layer hits the tapetum lucidum and is reflected right back at the retinal receptor layer for another chance at absorption. This is why cat eyes shine in the dark. Their sensitive whiskers, quick reflexes and acute hearing also help the lynx hunt at night.

Particular to the lynx is its characteristic short tail, long legs, and tufts of black hair at the tips of its ears. Their fur is very soft, and lynx have long been hunted for their coats. Some populations were almost driven to extinction during the 1950s and 60s, when demand for cat furs was at its peak. Lynx are still hunted today, but protection measures and a decreasing demand for furs are helping the species.

Did you know: Mother lynx have been observed hunting cooperatively with their offspring.

Photo by Art G.

Alaskan Husky (Canis lupus familiaris)

• Type: Mammal
• Family: Canidae
• Habitat: Domesticated
• Location: Worldwide
• Diet: Omnivore
• Average lifespan in the wild: 17 years
• Size: 20-25 in (50.8-63.5 cm)
• Weight: 35 to 50 lbs (15.8-22.7 kg) for females; 45 to 60 lbs (20.4-27.2 kg) for males

The Chukchi people of northeastern Asia developed the Siberian husky, a sled dog well adapted for hard work and very low temperatures. They were bred to pull for long distances at a brisk speed while expending a minimum amount of energy.

Similar in appearance and stature is the Alaskan malamute, which was developed and used by the Mahlemut people of northwestern Alaska. Modern sled dogs, or Alaskan huskies, are a mix of Siberian huskies, Alaskan malamutes, and other breeds selectively bred for speed and endurance, with the hope that puppies will be born with an instinctive desire to pull. Their coats are thick, to keep them warm in arctic conditions, with a coarse overcoat and a wooly undercoat. Deep chests give the dogs the large lung capacity needed for distance running, and powerful shoulders give them the strength to pull the sleds. Sled dogs are medium sized, usually under 55 lbs (25 kg). Any larger and size becomes a disadvantage—it is harder for the heart to pump blood and oxygen to the extremities of a larger dog.

Huskies are social animals that live in packs and cooperate to hunt. The “pack mentality” translates well to sled racing; the best mushers work as pack leaders, making decisions for the pack. Huskies, like all domesticated dogs, are extraordinarily good at taking cues from humans. They can instantly change course when directed by the musher’s vocal commands. Scientists believe that this ability to follow human commands was a selected trait in the first domesticated dogs. Domesticated dogs have been living with humans longer than any other animal. Based on DNA analysis, scientists believe that the domestication of the dog happened at least 15,000 years ago, maybe even earlier. Gray wolves, the ancestors of all domesticated dogs, do not have this ability to take cues from humans, even when raised by them. In a test to see if dogs could correctly read human communicative signals to locate hidden food, 9 out of 11 dogs successfully found the food. Dogs performed much better on the tests than chimpanzees.

Did you know: When running races, like the 1,100-mile Iditarod, it is important for the dogs to eat a lot—nearly 10,000 calories per day.

Related Episode:

• Dogs That Changed the World

Red Deer (Cervus elaphus) also known as Elk in North America

• Type: Mammal
• Family: Cervidae
• Habitat: Temperate forests, open woodlands, and mountainous areas
• Location: Broad distribution; across Europe, Asia, and into North America
• Diet: Varies by season and what is available; mainly grasses, plants, twigs, and mosses
• Average lifespan in the wild: 8 or 9 years
• Size: 5.25-8.86 ft (1.60-2.70 m)
• Weight: 376-643 lbs (171-292 kg) for females; 392-1095 lbs (178-497 kg) for males

Red deer are social animals that spend most of their lives in male or female herds. The two sexes come together only during the annual mating season. Each spring, young are born. After several weeks of hiding their newborns in the brush, the mothers, called hinds, bring their young back into the female herd. The female herd follows the dominant female, who leads them to seasonal grazing grounds. During the summer, a herd may be composed of as many as 400 individuals.

The antlers of an adult male red deer can grow up to four and a half feet. During the autumn rut, males compete for mating privileges by bashing antlers with the dominant male. In order for a non-dominant male to mate, he must fight, although no challenger will fight unless he thinks he can win. The prize is access to breeding females, and the right of the winner to pass on his genes. In January, after the breeding season has ended, males lose their antlers. They grow back quickly at a rate of nearly one inch per day.

During the harsh winter, the red deer’s metabolism slows in an effort to conserve energy. Red deer have evolved in such a way that the animal can actually significantly slow its heart rate and lower its body temperature, which decreases the amount of energy it expends by nearly 17 percent and helps it to survive in severely cold climates.

Red deer have long been hunted by humans. In fact, red deer meat was found in the belly of a mummified hunter who died in the Alps over 5,000 years ago. Even today, these amazing animals continue to be a popular target for game hunters.

Deforestation and urban expansion pose major threats to red deer, as their breeding and feeding grounds are rapidly being cut off. Man-made roads pose another deadly hazard, though animal friendly “green bridges” are currently being built all over Europe to allow the red deer and other species to travel safely across roads and highways.

Did you know: Ovulating females prefer the vocal calls of larger males, and can detect body size based on the pitch and frequency of a call.

Related Episode:

• Prince of the Alps

Cuttlefish (Sepia officinalis)

• Type: Cephalopod
• Family: Sepiidae
• Habitat: Shallow reefs and marine channels.
• Location: Globally distributed in marine waters
• Diet: Mollusks and crustaceans, especially shrimp and crab.
• Average lifespan in the wild: 1-2 years
• Size: 20-30 in (50-75 cm)
• Weight: 11 lbs (5 kg)

Cuttlefish, along with octopuses and squid, are cephalopods—animals from an ancient branch of the tree of life that have been trolling the oceans for more than 500 million years. Cuttlefish were around long before the first shark or fish ever evolved. Their cephalopod ancestors were encased in a shell that acted as protection from predators, but the modern cuttlefish has developed an even better defense: camouflage.

A cuttlefish’s skin contains over twenty million chromatophores, cells of pigment attached to miniscule muscles. By gently flexing these muscles, the cuttlefish releases pigment into the outer layer of its skin, allowing it to control its coloration and body pattern to emulate virtually any surroundings and thereby hide in plain sight. The cuttlefish’s highly specialized skin also helps it hunt, communicate, and mate. Males aggressively ripple and flash at rival males in competition for access to females. The larger and more impressive male usually wins, but sometimes a smaller male can successfully mate via female impersonation; if a small male can grab a female and quickly disguise himself to look like her, the larger male may not notice the two are mating.

Each cuttlefish has a pair of undulating fins that span the length of their body and help the creature to swim and maneuver; for any quick movements, it propels itself by shooting water from its gut. In the middle of eight forward-reaching tentacles, there is a small beak, which cuttlefish use to break open the shells of mollusks, crabs, and other crustaceans. Cuttlefish also have two longer tentacles, with a single suction cup at each tip. They use these elongated arms to grab their prey.

Cuttlefish have a short life span, but they grow quickly. They may only live one or two years, but some species can grow up to about 23 lbs (10.5 kg). Since they have such fast growth rates, cuttlefish are careful not to expend too much energy and usually spend about 95 percent of their time resting. Cuttlefish also have an internal structure called a cuttlebone that allows them to conserve energy by helping to keep them buoyant. The cuttlebone is a long, oval bone filled either with gas or liquid, depending on the time of day and cuttlefish’s desired buoyancy. These bones wash up on shore when cuttlefish die, and they are collected by people and sold as a calcium supplement treat for domesticated birds.

Cuttlefish produce a brownish ink, which they squirt to confuse predators when threatened. Humans have long used this ink in art, and the color name sepia takes its origin from the cuttlefish species name, Sepia officinalis.

Cuttlefish generally live in shallow reefs, but they can also live in channels and deeper waters up to 650 ft (about 200 m). They are distributed around the globe, and over 120 unique cuttlefish species have been discovered. New species continue to be identified, and while no cuttlefish species is currently endangered, increased fishing by humans could become a threat.

Did you know: Cephalopods are considered one of the most intelligent animals in the sea, and their cognitive abilities have been widely studied. Social learning in cuttlefish has been documented, and cuttlefish have even been trained in a lab to swim through T-shaped mazes.

Related Episode:

• Encountering Sea Monsters

Honeybee (Apis mellifera)

• Type: Insect
• Family: Apidae
• Habitat: Hollow trees in forest habitats, and beekeeper hives
• Location: Native to Africa and Europe, but spread by humans to temperate and tropical climates worldwide
• Diet: Herbivore
• Average lifespan in the wild: Workers, 15 – 38 days in summer; queen bee, as much as 3 years
• Size: Worker, .5 – .6 in (12 – 15 mm); queen, .7 – .9 in (18 – 22 mm)
• Weight: Worker, .0035 ounces (100 mg); queen and drones, .007 ounces (200 mg)

Like ants and termites, common honeybees, which are black with characteristic orange-yellow rings on the abdomen, are social and cooperative insects. Three different types of bees inhabit a colony: a queen, workers, and drones. The queen bee, which is longer and heavier than worker bees, is the only sexually developed female in the colony; using a specialized organ called an ovipositor, she lays the eggs from which all of the bees in a colony emerge. Worker bees, which forage the flowers in meadows, open woods, gardens, and agricultural fields for pollen and nectar (which is converted into the honey that helps to feed the colony), and build and maintain the hive, are sexually immature females. Their ovipositors are modified into stingers. Male bees, or drones, don’t forage; they may help maintain the temperature of the hive, although their primary role is to fertilize the queen. Because they have no ovipositors, they also don’t have stingers.

Bee colonies are maintained all over the world to pollinate agricultural crops. In the winter of 2006-2007, beekeepers in the United States and other parts of the world began to report the catastrophic loss of colonies, a phenomenon dubbed Colony Collapse Disorder. While the death of some bees in a colony is normal during winter months, the recent number of deaths has been unusually high, with some colonies losing more than 75 percent of their bees. After such devastating die-offs, the colony can no longer sustain itself. Scientists are still trying to explain the phenomenon, which threatens the economic future of the 130 fruit, vegetable, nut, ornamental, and fiber crops in the U.S. pollinated by honeybees.

Did you know? Forager bees will fly about 500 miles before their wings wear out and they die.

Related Episode:

• Silence of the Bees

Star-Nosed Mole (Condylura cristata)

• Type: Mammal
• Family: Talpidae
• Habitat: Areas with moist soil and poor drainage, such as forests, marshes, peat land, and the banks of streams and ponds.
• Location: Native to eastern North America, from Quebec and Newfoundland, south to at least Virginia, and west to North Dakota. Also found throughout the Appalachian Mountains.
• Diet: Carnivore (vermivore)
• Average lifespan in the wild: 3-4 years
• Size: Length: 6-8 inches (15-20 cm); tail: 2.6-3.4 inches (65-85 mm)
• Weight: .12 lbs (55 g)

Set aside the 22 fleshy pink tentacles that form the “star” on the nose of this mole, and it remains an odd-looking creature. The mole, which is covered in dense, blackish brown, water-repellent fur (ideal for its life in moist, mucky soil), has broad, scaly feet with large claws for fast digging, a stout cylindrical body, and a long thick tail that swells with fat to three to four times its normal size during the winter. The males’ testes also expand during the mating season (once yearly, roughly mid-March to April, although females may breed a second time if their first litter is unsuccessful), and can reach nearly nine percent of the animal’s entire body weight.

Appropriate to its life largely underground, the star-nosed mole is essentially blind. However, thanks to the tentacled star, the mole has perhaps the best sense of touch of any mammal in the world.

Each of the .03-.16 inch-long (1-4 mm) tentacles is covered by about 25,000 minute touch receptors, known as Eimer’s organs. The receptors come in three varieties, including one that senses the microscopic texture of objects, believed to be unique to the mole. The tentacles, which are also thought able to detect the minute electrical fields produced by aquatic animals as they move through water, move with lightning speed, and can touch as many as 12 objects per second. This allows the mole to rapidly identify and consume small prey, which consist of worms (including leeches), aquatic insects like dragonflies and damselflies, and the occasional terrestrial insect, mollusk, and small fish.

Star-nosed moles are currently relatively common, but the destruction of wetlands could adversely affect their status.

Did you know? The star-nosed mole blows and re-inhales air bubbles underwater as fast as five to ten times per second to track prey.

Cheetah (Acinonyx jubatus)

• Type: Mammal
• Family: Felidae
• Habitat: Areas with expanses of land, dense brush, and abundant prey, such as grasslands, semi-desert prairies, and mountainous terrain
• Location: Primarily Africa (where 90% live on commercial farms), mostly the sub-Saharan region, but range once extended into India; some are still found in parts of Iran.
• Diet: Carnivore
• Average lifespan in the wild: Up to 12 years
• Size: Length: 45-55 inches (115-135 cm); tail up to 33 inches (84 cm)
• Weight: 90-140 lbs (40-65 kg)