Buffalo, deer, antelope, rabbit, coyote, wolf, beer, cougar, prairie dog, wolverine, badger, muskrat, beaver, etc.
Along the pioneer trail, Mormon pioneers would communicate by leaving notes to passengers behind them written on buffalo skulls. The skulls would then be placed on the side of the trail so that those traveling along the trail would see them. These notes could vary from notifications of where to obtain food and water to messages to individuals.
Council Bluffs (called "Winter Quarters" by the Latter-day Saints) was one of the primary settlements along the so-called Mormon Trail after the Saints were forced to leave Nauvoo, Illinois. As immigrants pushed westward, they would camp at Winter Quarters until they had finished preparations for the balance of the trek. Thus it can be said that the Mormon Trail did indeed run through Council Bluffs.
English was the main language spoken by the Mormon pioneers, but many came from other areas of Europe, especially Scandinavian countries. Other common languages on the Mormon trail would be Swedish, Norwegian, Dutch, and German. Some trail guides also spoke some Native American langauages or Spanish because they encountered many Native American tribes and Mexican or Spanish people along the way.
The Mormon trail crosses several rivers. Probably the most well known would be the Sweetwater River near Martin's Cove in Wyoming.
The main wildlife would be deer, bear, antelope, buffalo, cougar, prairie dog, chipmunk, squirrel, badger, muskrat, etc.
If I were traveling to Wyoming along the Chisholm Trail, I would likely take a route that branches off toward the west after reaching Kansas. The Chisholm Trail primarily served as a cattle-driving route from Texas to Kansas railheads, so I would need to navigate through the plains, possibly connecting to the Oregon Trail or the Mormon Trail, which lead further northwest toward Wyoming. This detour would allow me to reach my destination while following established pathways.
On horse, on foot, in a wagon or pulling a handcart.
The word you're looking for is "Xerophyte." While it's not directly associated with the Oregon Trail itself, xerophytes are plants adapted to survive in arid climates, which could be relevant to some of the regions encountered along the trail. The Oregon Trail traversed various ecosystems, including areas where drought-resistant plants would thrive.
The Mormon Trail didn't have one specific leader or group of leaders. Rather, each individual group that traveled the trail appointed a leader who was knowledgable about the terrain and had the skills needed to lead them safely to the west. Most people who travelled the Mormon Trail were Mormons, and therefore had the same religious leaders, but the religious leaderswere not generally the trail leaders (although in some cases religious leaders returning from missions abroad would assist in leading groups on the trail).
The Mormon pioneers often avoided the less travelled routes so that they could avoid confrontations with other travelers and not have to compete for food and resources found along to trail. They prepared the way for other travelers by planting small crops along the trail.
The Mormon trail wasn't about seeking out new lands, it wasn't about looking for gold or riches from the land either. It was about a group of religious believers having to leave their homes in the dead of winter and seeking religious freedom. This is what makes the Mormon Trail and the journey on the trail so very different than other journeys.The only thing that is similar to it would be the Puritans leaving England seeking religious freedom as well.
Along the Mormon Trail, people tried hard to keep their spirits up despite the rough conditions. During the day they often sang while they walked, and during the evenings they would have music and dancing. Sundays they would usually rest for the day to hold worship services and visit with each other.