Forerunner fauna and flora

Througout the Halo Universe many Forerunner animals, plants and other lifeforms are shown or hinted at. Below are many known Forerunner fauna and flora.

Land Animals


Halo Dinosaurs are native lifeforms to Halo, possibly exclusive to Installation 04. They are both bipedal and quadruped in stature and somewhat resemble Earth's dinosaurs. The larger animals' names are Thorn Beasts and the smaller one has been identified as a Blind Wolf. The Blind wolf was also meant to be rideable by the player as well as have the ability to bite as an attack. The Blind wolf has 2 very large teeth coming out of its mouth and walks on 2 legs, it may also be seen in large packs in the E3 2000 Halo trailer.

Although they did not make it to the final cut of the game, this does not exclude them from Halo as a whole. For example, Engineers didn't make the final cut for Halo: Combat Evolved either, but they were depicted in the Halo Novels and Halo Wars. A pack of Brutes ate a Thorn Beast in Halo: Contact Harvest. It's unknown if these animals are meant to be there, or if they are even canon to the plot of Halo: Contact Harvest, but just unseen.

The main reason they did not make it into the final game was due to balancing issues as to how they would react, especially to the flood. There were also a lot of glitches.

Sea Creatures
Originally there were plans for sea creatures to inhabit the water, as seen in The Silent Cartographer the water is fully explorable in Halo: CE, which would make sense to have sea creatures. In early Halo there was also a spear gun which could be used on the sea creatures and underwater enemies. A few sea creatures have been seen in early videos like sea monsters and fish. The creatures and spear gun did not appear due to balancing problems.

The Dino-Birds
Main Article: Dino-Birds

On the levels Delta Halo, and Regret, there are birds flying around in the sky, usually flying in circles or ovals. They are also in the Halo 3 multiplayer maps Guardian, and Epitaph where they can be examined more closely by using Flycam in Theater or Editor Mode in Forge. At first they seem like dinosaurs, but they are seen in High Charity, so it is also possible that the Covenant brought "food," and they are seen on Installation 05 because they would breed quickly. But then, if they are dinosaurs, the Covenant might bring specimens to their holy city. It may never be known if they are dinosaurs or wildlife brought by the Covenant to use as hunting game. This could be confirmed by the existence of the supply ship complete with a hunting preserve, Infinite Succor from the Halo Graphic Novel. Bungie may very well be the only ones to ever know.

Also, since we know that Halo contains a vast multitude of terrains and environments, much like Earth, it is possible that life has been developing on Halo over the 100,000 years that they have been dormant, such animals like the dino birds. Another reason why animals may NOT be seen is because they have the calcium store necessary for the Flood to infect, so the animals may have been destroyed by the guardians of the construct, and only avian-like animals survive since it was mentioned that Drones do not have sufficient calcium mass to sustain the Flood.

In Halo 2 and Halo 3 these "birds" can be shot and killed; they are always moving, and therefore difficult to hit. After being shot once by any weapon they give off red blood and fall straight down. There is only one falling animation.

A fun thing to do in Halo 2 is while your on the gondolas on Regret or otherwise waiting for combat you can grab a carbine or Beam rifle, and try and snipe them. This "hunting" is especially fun if you have a co-op friend, and the two of you will try and see who gets the most kills.

It is highly likely that they were brought over from another place to the Halo Installations because the Forerunners could have used them as food for the Flood so they could further study them. However the birds could be too hard to obtain for the Flood because of their flight and/or their bodies do not contain enough calcium for the Flood to feed off of.

Moths
Main Article: Moths

These moth-like creatures are only seen in the dark Swamps of Alpha Halo. They are one of the first animals seen in Halo: Combat Evolved. You cannot interact with the moths and they are not seen in Halo 2 or 3.

Other
Animal calls were heard in 343 Guilty Spark along with the moths. One of the most common sounds was the sound of an owl hooting. There were also some cricket sounds. It is unlikely that these sounds are indeed owls and crickets, but perhaps an animal that is similar. It also could be possible that they are artificial sounds made by the forerunners to make it seem more life like.

Sea Worms
Main Article: Sea Worms

Seen on the level Silent Cartographer, these Sea Worms floated harmlessly on the surface of the water. When exploring the water, the worms can often been in the waters edge, floating.

Flood Stalk Plants
Flood Stalk Plants can be commonly seen in the multiplayer map Backwash, and seen often in the campaign levels 343 Guilty Spark, Gravemind and High Charity. These plants appear as large, thick stalks, as the name suggests.

Forerunner Trees
Forerunner trees are aesthetically similar to modern trees on Earth. They are found on Forerunner Installations and seem to be quite abundant. The trees would help keep a balanced ecosystem and make Halo seem more natural. There are many different trees seen on Halo throughout the trilogy.

Terrain
A majority of the terrain on Halo is grass with masses of trees. Even parts where it is snowing there are at least a few trees and patches of grass. Halo has various environments and seasons, and weather might differ on different parts of the ring. All of the plants and trees and other flora seen on Alpha Halo, Delta Halo, and the Ark were obviously easy for the Forerunners to obtain or else these wouldn't have been able to get on the rings. If there really are no fauna on the different Installations, then it is likely that the flora on the Installations are less advanced from an evolutionary point of view than the flora on other planets because the flora on the Installations wouldn't have to compete with fauna for nutrients, and thus would have less of a reason to evolve.