1. Explain to students that many bison in
the central part of Yellowstone migrate considerable
distances in the winter, even though it is not
unusual for the ground to be covered by more
than two feet of snow.
2. Give each student a copy of Attachment
A. Explain that Attachment A is a map of
Yellowstone National Park. The Mary Mountain
bison migration corridor is in the central part
of the park, stretching between Hayden Valley,
across the Central Plateau, to the Lower and
Midway Geyser Basins on the Firehole River.
Have students locate this area on their maps.
3. Give each student a copy of Attachment
B. Explain that Attachment B contains a
series of models and maps of the area of the
Mary Mountain bison migration corridor.
4. Ask students to examine the Colored Relief
Map of Yellowstone National Park and once more
locate Hayden Valley, the Central Plateau, and
the geyser basins on the Firehole River. Ask
students to study the elevation and topographic
changes shown on the map in this part of Yellowstone.
5. Direct students to proceed to the Shaded
Relief Map of the Mary Mountain bison migration
corridor. Be sure students realize this is an
enlarged view of the specific area they just
located on the other two maps. Have students
identify the Madison/Firehole Rivers, Yellowstone
Lake, the Grand Canyon of the Yellowstone, the
Yellowstone River, and Hayden Valley on the
Shaded Relief Map by correlating between the
previous two maps and the Shaded Relief Map.
Students should write in these place names on
the Shaded Relief Map.
6. Direct students to examine the Digital
Elevation Model in Attachment B. Be sure they
can once again identify important geographic
features for reference such as the Madison/Firehole
Rivers and the Yellowstone River. Now ask students
to observe how the colors of the elevation model
reflect the elevation changes depicted on the
two relief maps.
7. Direct students to create an elevation
key on the Digital Elevation Model. They should
describe the order in which colors reflect elevation
changes from low to high. (white, blue, green,
yellow, red, pink, purple)
8. Direct students to examine the Thermal
Ground Heat Model and then place it beneath
the Shaded Relief Map, holding both papers before
a lighted window. They should mark areas of
thermal ground heat on their Shaded Relief Map
with a pencil.
9. Direct students to place the Thermal Ground
Heat Model beneath the Snow Depth Model. Ask
students if they observe similarities between
the two models. On the basis of these similarities,
what would they infer the darkest areas on the
Snow Depth Model indicate?
10. Direct the students to place the Mary
Mountain Bison Migration Corridor and Home Range
map beneath the Shaded Relief map and hold it
against a lighted window. Instruct students
to trace the Migration Map onto the Shaded Relief
11. Ask students how the bison migration route
corresponds with the geothermal ground heat
areas they drew on their map. Ask if the snow
depths would vary along this route and why.
Ask students to indicate areas where the bison
would “hopscotch” between areas
of deeper snow.
12. Direct students to express, in writing,
an inference on how thermal activity influences
bison migration in the central part of Yellowstone,
using at least one specific reference to information
obtained by using the models and maps.