Name:
Class:
Date:
Interpreting a Food Web
Introduction
Each of these organisms are found within Yellowstone National Park in the western United States. Write the
name of each organism below the picture. Start with the plants, from left to right: bearded wheatgrass, aspen
tree, gray willow tree, sagebrush, and algae. The animals include: mayfly, coyote, bald eagle, deer mouse,
bison, elk, red fox, gray wolf, cutthroat trout, beaver, harlequin duck, snowshoe hare, and grizzly bear.
Food webs use arrows to show predator-prey relationships. In each relationship, the arrow points to the
predator. Use the following guidelines to fill out each of the arrows of this food web.
a. Pond algae is eaten by mayflies, and cutthroat trout.
b. Bearded wheatgrass and sagebrush are eaten by elk, bison, snowshoe hares, and deer mice.
c. Gray willow leaves are eaten by deer mice, elk, and bison.
d. Aspen trees are eaten by beavers. The leaves are eaten by elk.
e. Mayflies are eaten by harlequin ducks, grizzly bears, cutthroat trout, and deer mice.
f. The snowshoe hare is eaten by coyotes, wolves, and foxes.
g. Cutthroat trout are eaten by bald eagles and grizzly bears.
h. Beavers are eaten by coyotes and gray wolves.
i. Harlequin ducks are eaten by red foxes and bald eagles.
Analysis Questions
j. Deer mice are eaten by coyotes, red foxes, grizzly bears, and bald eagles.
k.
Elk and bison are eaten by coyotes and gray wolves.
1. Gray wolves may also feed on coyotes and red fox.