Ecology of the Terror Birds

I have nothing but respect for Terror Birds because the moment you don't, you're bird food. - Tannon Elven Ranger

Introduction

Terror Birds are a broader category of an ancient line of 2 legged flightless birds. Many varieties such as Diatryma, Gastornis, and Titanis are well known and feared animals in the remote areas they inhabit. These birds are often ignored or overlooked for their predecessors, the dinosaurs. I'm here to rectify that problem as Terror Birds are fascinating creatures I've found in my many years of research. Their bravery or stupidity is unmatched, yet they surprise even the most prepared of opponents. They are also wonderfully affectionate to those they trust and great friends. Just don't be on the opposing side, or you'll see where they get the name Terror Bird.

Physiology of the Terror Bird

How to Identify the Terror Birds

Most are familiar with emus, ostriches, or more modern bipedal birds. But remote pockets of the world house some of the most terrifying and ancient varieties. There are several sub-species of Terror birds that range from 3-feet tall to a massive 15 feet. Their wings are small and tucked to their sides, even more so than a chicken. Their thick muscled legs with long talons are more than enough to show the power they possess. Their necks are proportionally much thicker than their ostrich cousins, and their beaks are that of a predator.

Males are brightly colored, whereas females will have the same colors but muted. For instance, the smaller 3 foot tall, Caprims, both are red and black in coloration to hide in the shadows and look like a flower in their jungle homes. The females are just still black, but their red is only slightly muted. Males also have crest feathers that they can lift but usually keep pursed backward unless interacting with their mate.

Origins

When the majority of dinosaurs left the Material Plane, obviously aside from the remaining dinosaur islands, birds filled the niche of super predators for a short time. Birds are closely related to dinosaurs and thus quickly adapted to the same super-predators, although arguably much smaller than that of creatures like Allosaurus or Tyrannosaurus Rex. Since then, their direct competition of large cats, however, has dwindled their numbers. Leave it to a cat to keep a bird in check.

Hooked Beaks

The beaks of Terror Birds resemble something closer to raptors (bird raptors) like eagles and Rocs. The wicked spike that the end of their beak forms is excellent for pulling off large chunks of flesh while eating. Though, their bigger purpose is paired with their incredible ability to thrust their heads downward at a quick speed with accuracy and puncture prey. Using the hook as the pointy side of a pick, they can sever the spine of even large creatures such as bears in as little as 2 pecks. Very few animals can kill so efficiently and quickly, something their size or larger, even dragons.

Killer Legs

Terror birds are fast runners with stamina. Their thick legs give them incredible power and speed. They can run down prey, attackers, or about anything if needed at rates close to 40 mph. While they can't maintain this speed for more than a few hundred yards, they can run at 15 mph for much longer distances, making them excellent for long-distance travel.

On top of their astonishing speed is their agility. Their legs are positioned more towards the bottoms of their hips than the sides, and with the added rotation of ball socket joints, they can make quick leg pivots. While they can't be at top speeds to make sharp adjustments, it's faster than even antelope. Their sharp claws can dig into the earth for traction on a quick turn, giving them a slight edge on adjusting direction.

Lastly, with their backward bending legs and stiff muscles, they can jump with incredible power. While this ability diminishes with body size, even the largest Terror Birds can jump 2 1/2 times their height. They flap their small wings fervently when doing so, not enough to create lift but enough to slow their fall. This flapping slow-fall is less effective than that of a chicken but the same concept. Their jumping is also well suited to distance if needed, making jumping large streams or even small rivers a great way to corner prey.

Eyes of a Killer

Terror Birds have exceptional eyesight in both light and dark, with their heavily dilating pupils. Their eyes are also huge in general to head size about 25% larger than an eagle's eye to head size ratio. They are also forward-facing, giving them that deadly accuracy. Because their eyes can move in their head, they also possess tremendous peripheral vision.

Hunting and Feeding

Terror Birds are carnivores; well, most are. They watch their territory for prey and when hungry bolt in pursuit. Once a victim runs, they can easily catch them by grabbing them, with their beaks, if small enough, or quickly killing bigger prey. Their favorite tactic is to run beside a fleeing animal and slam their hooked beak into the skull base, downing the creature immediately. Their beaks are strong enough to crush through the skull of a human, making a quick and easy meal.

Once they have slain a creature, they will begin to strip off flesh to eat. Terror Birds are not fond of eating fur or hair, though, and will usually peel the skin away to get to the more tender areas. However, it isn't possible to always avoid fur and hair on creatures. They can process the hair but not as easily and often causes stomach discomfort. Once they've eaten their fill, they either leave the food for scavengers or drag it back to young.

With smaller prey, often, they snatch up the poor creatures instead of quickly killing them. Often they will violently and repetitively slam their target on the ground, either killing or stunning them. They are also mighty kickers and can crush bones with a single blow.

Life Cycle

Chicks are hatched only 1 egg at a time. Once they hatch, it is only a span of a few seasons before they strike out on their own. Their parents both care for the chick until full maturity. Once grown, they are about half to nearly full size, depending on the kind of Terror Bird.

Adults live around 40 years and start to show signs of significant degradation at 37. While slower and less capable at venerable ages, Terror Birds are still scrappy fighters able to fend off attackers well enough. During this time, they may produce as many as 2 dozen chicks, but sadly only 1/3rd of those chicks will live to adulthood in most cases.

Common Diseases

Terror Birds are affected by only a few diseases, but most are fatal. Those who raise terror birds often have to quarantine and even kill infected birds to keep the rest safe. Thankfully they are not widespread in any area, and if caught early enough simple medicine, and divine intervention can save the animal.

Pox

While Pox to many other creatures is a deadly and contagious disease, humans included. Terror Birds can be an early specimen, as they pick it up from eating prey infected with the virus. Pox is spread by parasites such as flies and lice that can be found on less fortunate birds. Adults start to lose feathers in patches, but chicks outright perish after only a few weeks.

Bleeding Egg

As some varieties of Terror Birds produce regular eggs as decoys, it's easy to spot an infected bird with Bleeding Egg. First, the egg's outer shell is soft and reddish in hue as the egg is filled with both yoke and a fair amount of blood. While this condition rarely harms the adults, they will no longer produce viable young, and those eggs that are fertile are stillborn. For Terror Bird ranches, this is usually immediate death to prevent the spread of the disease as blood eggs are not a viable product.

Newcastle

Named for the biologist who identified the disease, Newcastle is a relatively new discovery. Symptoms include hyperactivity, inability to focus, take a 3 legged position (using their head as a 3rd leg), staggering backward, and lack of self-preservation. This condition is so far only found in wild Terror Birds. The infection rate is rather low and seems only to be a bloodborne transfer.

Habitat Range

Terror Birds are mostly tropical in origin. They prefer forests, plains with tall grass, or even some rolling hills. They aren't well balanced in rocky or icy terrains and tend to fall prey to other carnivores from losing their footing. While most Terror Birds stay in warmer climates, a few breeds have ventured further into artic regions, although sticking to forests and fields.

Ground Nesters

These gigantic birds are unable to nest in trees like many others, or the cliffs of mountains such as giant birds like Rocs. Thus they make ground nests that usually are large enough for 2 terror birds to squat side-by-side. They are very protective of their nest and territory, continually patrolling and keeping an eye on potential dangers.

The birds hide their nests in foliage and brush and create multiple nest sites as decoys that are more obvious to find. This behavior has been altered in domesticated birds to produce eggs like that of a chicken. Significantly larger sizes of eggs are produced, between 5 and 8 inches tall.

Domesticated Terror Birds know their trainers, and even the usual people around them, much better than domesticated griffons. They are also usually trained to avoid attacking the people they work with while hungry, which is rare for such a predatory animal. They are very unforgiving, though, and if a person has wronged them, they don't hold back.

Terror Bird memory is long and will remember individuals of many creatures for a long time. While in the wild, this skill is less utilized, maybe except for hunters or rangers. Domesticated ones can be very loyal as a result and even recognize the names of friends.

Interactions with Other Creatures

Domestication

First and foremost, the most common interaction is that with the Elven and Human communities that have domesticated terror birds. While Humans have domesticated the Brontornis, one of the larger varieties, Elves have attached more the Gastornis, which is, in comparison, is much smaller. Despite stocks of these birds coming from different types, they are both similar in domestication.

First, a domesticated Terror Bird is loyal but still a carnivore. They must be fed well enough, or hunger will cause them to be increasingly rebellious. Sometimes even picking off other members of a community to which they have no attachment. Second, they will only allow a few people to ride them also if they are well known and trusted.

Mating in captivity is a crucial process as keeping the correct genes, and friendly mentality is the whole reason they can continue to be used as allies. Unfortunately, it is a much more complicated process than in the wild. Unlike farm animals such as cows, Terror Birds prefer only one mate but most often mistake their care-taker as that role. This attachment is why until they find a mate in captivity, the trainers must keep a firm hand and distance until they are mature enough to be mated. These pairings of birds are often akin to an arranged marriage, and once they are bonded, they are much easier to give affection without negative attachment.

Not all Terror Birds are domesticated, but I suppose it could be possible. In my observations, all of them have that capability; even the dangerous and volatile Titanises have the capacity to hold violence in check.

Cats

Terror Birds have a natural aversion to cats. Not unlike other birds or dogs. However, these giant birds have no fear. They are nervous and often violent towards even small domesticated cats. They have a natural enemy in big cats and often come to blows for territory with tigers, lions, and saber-cats.

No Monster Too Big

While these predators usually only attack creatures, their size, or smaller, they are not afraid of any animal regardless of size. This selection doesn't mean they will attack the monster immediately but instead will ignore them unless provoked. If provoked, they unleash a fury that can take a young dragon off-guard and cause some harm. Domesticated birds will fight to the death for their riders and cause some severe issues, especially if outmatched. They had no natural predators in which they lived, maybe outside super ones like Hydras and Dragons.

Prey

Being predators, they favor killing their food but will eat raw meat from handlers, if domesticated. Live prey is a treat for them. While animals closer to their size are preferred, they will eat smaller creatures they can catch. Victims are usually quickly dealt with and eaten immediately. These birds do not play with food.

Battle Tactics

Terror Birds are no strangers to battle. Between defending their nests and taking down prey, they are fighting nearly daily. With this experience, they are not to be lightly taken when facing an aggressive bird. They are most often suited to a quick kill and 1 on 1 battle.

When facing a single opponent, the Terror bird tries to peck at the skull of their foe. With their powerful downward strikes, they can quickly finish even thick-skulled creatures with only a few blows, or 1 well placed strike. Their tactics are straight forward and aggressive. Squawking, pecking, and leaping at their foe keeps nearly anything on their heels. If an enemy is much larger than the bird, it will still come at them with full-force. When going for a kill, they can jump high and use their downward momentum to their advantage.

If facing multiple enemies, they can jump and kick at attackers from all angles. Wolves and other pack animals often mistake flanking them with a supreme advantage when they only need to swing their claws behind them for a fatal counter-attack. Terror Birds, however, are not fond of facing multiple foes and will strike faster than waiting for an attack usually.

Variations

Gastornins

Gastornis or plurally Gastornins are most popularly found in jungles and warmer forested environments. While they have been seen smashing nuts with their thick beaks, they are still dangerous predators. Standing at a comfortable 7-feet tall, they are imposing to even orcs for their strength and size. They are among some of the most hazardous bite crushing power and are used for crushing things in a utilitarian fashion.

Elves seem to use Gastornins in domestication most often because of shared environments. The domesticated Gastornins are the friendliest kinds as well. Gastornins enjoyment of both meat and nuts helps in keeping an ample food supply.

Gastornins are usually brown to black-feathered to hide in the forest homes better. They have bright blue skin around the face and neck along with a small, proportionally at least, gobbler like that of a turkey. Their eyes are large and yellow in coloration.

Brontornis

Brontornises are larger as far as Terror Birds go, as tall as 10 feet, and one of the slowest birds, only topping out at 25 mph run speed. However, they can carry two full-grown humans and is the only Terror Bird able to carry 2 riders of such sizes. Rarely are they used for beasts of a burden, though, as they are notoriously curious and often ransack luggage. They almost exclusively eat larger herbivores such as cattle and other herd animals.

For domestication, they make excellent mounts and body-guards. They are quite fond of standing in place for long periods on the lookout as they would on their plane homes watching a herd from a distance. Their beak is great at piercing armor as well, and they feed on armored animals by piercing a wound, placing their foot on the prey, and tearing the armor off. It works effectively against armored humanoids as well.

Feathers on Brontornises are usually lighter browns or greys. Their dull coloring makes it harder for the less gifted for sight herds to spot them in their stationary outlooks.

Titanis

The largest of the Terror birds reaching up to 15-feet tall are considered too dangerous to tame. Their beaks are also longer and more hooked than most varieties. They can run at speeds nearing 35 mph chasing down and tearing apart prey. They are voracious predators that attack many creatures on-site, when hungry.

Despite their size, they have vibrant and rich green colorations as they live in tall grasses around rivers. The cat-tails and swampy grass-fields are where they hunt for large fish, crocodiles, and any creature that finds itself wandering in the grass.

If they became domesticated, I would suppose it would have to be by larger peoples, such as orcs, that could stand at least half as tall to these massive carnivores. Halflings, unfortunately, would only be seen as prey, I fear.

Caprims

The smallest of the Terror Birds, Caprims are jungle dwellers that disguise themselves as flowers. They aren't afraid to attack humanoids if catching them by surprise, giving the black and red feathered birds the nicknames of Devil Flowers. They are fast runners and able to dart and dodge in the thick jungles nearly unhindered.

Domesticated Caprims make for quick messengers through thickly brushed environments. While they are certainly too small to ride, they make for a great companion that can follow directions better than a dog.

Diatryma

Diatrymas are known for their stark black feathers and Green eyes. They are not only nocturnal predators but also live in the underground tunnels beneath the surface. Some are tamed by under-dwelling peoples such as Drow, but ultimately they are free-roaming terrors of the dark. They are most likely to encounter Displacer Beasts, Hook Horrors, and other tough to kill enemies and thus live in flocks of up to 8 members.

Standing at a 6-foot tall posture when upright, they are taller than what the cramped tunnels allow. They make up for this by being the most flexible and creatively mobile Terror Birds. Their beaks are stiff but still narrow, and their skull is only slightly larger than the beak itself. Due to their improved flexibility, the Dyatryma can squeeze through areas as long as its head can fit through. They push with their clawed feet through cracks and pull by hooking their beaks on the stone.

While lighter creatures, such as elves, can ride them, they are most often used to fight. Their aggressive tactics and ability to traverse the dark better than many 4 legged animals gives them the advantage.

Kelenken

The Fastest of the Terror Birds, Kelenken, can top out at 40 mph. They chase down prey in open fields despite nesting in the forests. Found in colder and temperate regions, they prefer to keep away from larger predators like bears, which they have trouble bringing down. They are some of the rarest varieties outside of domestication. They are white-feathered with black accents around the eyes and wings. Their beaks are a stark orange, though, and tend to be the only visible aspect in a snowfall.

Kelenkens are domesticated for riding as they stand up to 9 feet tall and can bear 1 rider at nearly full speed. Most often though they are bred for racing and bets, Dwarven kingdoms are primarily known for their racing Kelenken.

Death Birds

While the name is ominous, it is rightfully earned. Another variety yet to be tamed, Death Birds are dangerous predators of humanoids. Also known as Phorusrhacos‭, they have adapted to specifically hunting humanoid creatures over time. Their markings are ominously dark grey or black with a white-tipped beak and white accents around their face. Death Bird markings when looked at from about 6 feet to 10 feet tall and facing them look as if they are a floating humanoid skull on a black body. Death Birds are visually adapted to keep their prey stunned in fear. They also give off a low rumbling that un-nerves many humanoids as a frightening tactic to keep them off-guard.

Living in warmer grass-lands and forests, they are well known to many humanoid tribes and even hunted as a ritual for some cultures. While they aren't domesticated in any, understandably why I do believe it is still possible. They would make for 1 intimidating mount for sure.

Axe Beaks

Andalgalornis or better known as Axe Beaks, are unique among Terror Birds for their beaks being hooked on both the bottom and top of their bill. Standing at just over 7 feet tall, they hunt in tropical regions. The upward swings of their heads are just as deadly as the downward strikes. This top spike can be helpful as the tropical forests hide predators in the trees and the ground. Their unique bills give them another angle in which they can attack.

They are brown with white feathers on their faces and undersides. Their tails are the most unique and can fan upwards, in a mating display, like a peacock or turkey.

DM Notes

Terror Birds are a fascinating group of extinct animals that came just after the extinction of the dinosaurs. I drew inspiration for this article based on the real-world scientific names as well as some fantasy ones I made myself. I highly suggest adding some spice to your campaign to use birds instead of horses in some cultures as horses don't do well in forests.

Here are some hooks for Terror Birds:

A silent ambush from the trees or tall grass (combat encounter)
A bird carrying an injured rider is lost and needs help
An injured bird tells of a larger danger in the area; the Terror Bird is a fierce fighter, so whatever laid the poor creature low must be strong.
A lone giant egg sits in a nest. Is it abandoned? Or are the parents around
The races are off! Except one of the riders is mysteriously killed, and the bird takes off to race with a dead jockey.
Someone is cheating to fix the races!
A trainer couldn't find an acceptable mate for his bird and needs your help to find it a suitable mate.

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