A Sheepeater Indian family.
Cutthroat Trout
An osprey landing on its nest.
The 17 species of fish in Grand Teton National Park include brown, brook, rainbow, and lake (Mackinaw) trout. These introduced species are found in a number of lakes and streams. Perhaps the most impressive fish is the Snake River cutthroat trout, the native trout so dependent on the park’s natural aquatic system. The deep red or orange-red marks under its jaws give the impression of a slashed throat, hence cutthroat. The Snake River cutthroat is a distinct subspecies of the cutthroat trout identified by the hundreds of tiny dark spots on both sides of its body. In spring, particularly May and June, the Snake River cutthroat will travel upstream into tributary waters to spawn. The female digs a nest (called a redd) in the gravel and the male and female lie side by side while simultaneously contributing the sperm and eggs. The fertilized eggs settle to the bottom and hatch into fry within 40 days. The young fish usually remain in the tributary stream until fall but will sometimes wait a full year before migrating to the river. Juveniles, called fingerlings, and sub-adults feed on a variety of aquatic invertebrate larvae such as caddisflies, mayflies, and stoneflies. The older fish become more predaceous and feed on a variety of smaller species of fish living in the river. The cutthroat trout reach sexual maturity at three to four years of age. Few cutthroats live longer than five years. The post-spawning mortality rate is 50 percent. The Snake River cutthroat trout indeed delights the angler, but more important is its role in the wildlife community. The cutthroat consumes aquatic insects, invertebrates, and small fish, helping to keep these populations in check naturally. This trout is also consumed, providing food for bears, eagles, ospreys, and otters. If the fish population declines, so will the animals that depend on it for food. As fishing pressure continues to grow, park managers may have to protect this natural population of Snake River cutthroat to maintain the national park’s wildlife community.
Mule deer, named for their large ears, occur in surprisingly small numbers in the park. Competition with the large elk herd and deep winter snows may be limiting factors.
Wildlife and Wildflowers
When the Shoshone Indians sat down with government officials at Fort Bridger in 1863 to conclude a treaty that would define their lands, the parcel that the parties arrived at totaled 30,000 square miles. A very small part of that was Jackson Hole, but this was such rich hunting ground in summer and fall that even the Shoshone dared not lay sole claim to it. Blackfeet, Bannock, Crow, Gros Ventre, and probably other tribes were drawn here to hunt. What would you have seen on a hunting trip in those days? Bison, pronghorns, and at least three times as many elk as exist here now, but far fewer deer. Near wall-to-wall beaver along the waterways, but nary a moose. And bighorn sheep peering down at you from nearly every crag and butte.