Hydra

Basic Information

Anatomy

The typical hydra resembles a large, stout-bodied reptile with multiple writhing, serpentine necks culminating in snakelike heads. If one of these heads is cut off, two more grow from the stump unless it is seared with fire or acid.

Genetics and Reproduction

Their unique form of regeneration is linked to the hydras' method of reproduction: the new heads generate as embryonic sprouts in submuscular fossae within the creatures' necks, waiting to transform into new heads when the ones they reside in are severed. If this does not happen, the larval heads grow inside the neck until they are either disgorged in leathery cysts, which the hydra then broods like eggs until they hatch into swarms of tadpole-like larvae, or physically tear their way free of their parent's neck, at which point the largest larva attaches itself to the parent hydra as a new head and the rest move away as a swarm. The larvae remain together until they mature into young, multi-headed hydras, after which they leave the swarm to set off on their own.

Ecology and Habitats

Hydras live in warm or temperate swamps, although some have been reported as living in coastal reefs.

Dietary Needs and Habits

Hydras are carnivores, and need to regularly eat large amounts of food in order to sustain their regenerative abilities. They prefer larger prey, which they often devour whole and digest over long periods of time; a hydra can consume half its weight in food in a single sitting, after which it will be able to go on without eating for up to a week. Humanoids are particularly desirable prey, especially sturdier ones such as dwarves, but when prey is scarce, hydras can subsist on carrion or small swamp-dwelling creatures such as snails, worms, or frogs gleaned from swamp mud. Particularly hungry hydras can feed on vegetation, although given the choice they always prefer meat. Desperate times can see hydras engaging in cannibalism; hydras driven to this point will fight one another to the death, with the victor of these clashes then consuming every scrap of the loser's flesh.

Hydras are generally ambush predators, preferring to lay in wait to catch their prey as it moves by. Unlike the snakes they typically resemble, hydras depend largely on sound to hunt their prey. Their large size and regenerative abilities also ensure that if the element of surprise doesn't work, they can fall back on brute force to take down dangerous prey.

Additional Information

Social Structure

Adult hydras are solitary creatures; as asexual beings, they tend to see others of their kind only as competitors. However, hydras may tolerate the presence of conspecifics when resources are enough to support them, due to the aid that these can give in taking down large prey or fending off potential predators.

Symbiotic and Parasitic organisms

Hydras often live in symbiosis with small vermin, which feed on algae growing over their host's scales and on parasites infecting it. These symbionts are the only creatures that hydras will not try to devour.

Lifespan

500 years

Average Weight

4000 lbs.

Average Length

20 ft.