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Fingerprints in the Dunes Worksheet Answers
- Scientists find that moisture precipitates out of cooler air. Within
just a few miles, one area may receive only 10 inches of precipitation
a year, while only a few miles away, higher elevations may recive four
times that. Where does the most rainfall occur in the Great Sand Dune’s
area? The tops of the Sangre de Cristo Mountains.
- A star dunes is a special type of dune that forms only in places where
the wind blows from multiple directions. What factors influence which
way the wind blows? Topography (mountains,
flat areas, mountain passes) and general climatic patterns.
- During the winter, snow accumulates in the Sangre de Cristo Mountains.
This poster is set in autumn, when water from Sand Creek rarely flows
far into the dune area. During which months would you expect to find
water in Sand Creek? After the winter snow
melts (April, May and June)
- Mammoths, bison and other large mammals once lived on the sand sheet
thousands of years ago. Most died off or were hunted to extinction.
Bison have been reintroduced to a nearby ranch. Name one other native
species of large herbivore frequently seen on the sand sheet. Elk
are found on the sand sheet, but they were more restricted to the western
San Luis Valley grasslands before farming came to the valley.
- One plant found in the sand sheet is an economically important crop
native to the United States. Which plant fits this description? Sunflower.
Piñon pine is also becoming an economically important crop.
- At Great Sand Dunes, in some areas the water table is extremely close
to the surface. Name one feature that is found where the water table
is higher than the dune surface? Interdunal
pond, marsh, spring or creek.
- A nest made from twigs and grass about the size of your fist is found
beneath a rabbitbush shrub. Who might live here? Vesper
Sparrow and other small birds commonly nest in the protection of sand
sheet shrubs.
- Many desert plants contains waxy/rubbery leaves. Some shrubs' leaves
also provide shade for animals. Which of these plants provide abundant
shade for animals? Circle one. Rabbitbush,
blowout grass or scurfpea. Why might plants have waxy leaves? Waxy
leaves usually help a plant from losing water in the hot sun. They provide
a barrier from evaporation. Waxy leaves can also act like sunblock from
the sun's ultraviolet radiation.
- Bounding tracks lead across the dunes into the shrubs. A small pair
of prints and a large pair appear in-line together. What animal made
the tracks? Jackrabbits are trackable by their
unequal size prints. The rear paws leave a much larger print than the
forepaws.
- Paw prints seem to “trot” to the top of a small dune near
an interdunal pond.
What animal made the tracks? Coyotes would
be the most likely animal to produce trotting paw prints.
- A scattering of small, pink slender spiderflowers cover an area near
the interdunal pond. Nowhere else have you seen them. What other places
would you look for these rare beauties? This
rare species of spiderflower can be found in other moist areas in the
San Luis Valley and near the dunes. They are also found in New Mexico.
Always look for similar species to be found in ecologically similar
habitats when searching for rare plants.
- A small, 2-inch wide burrow leads down into the sand. Bits of blowout
grass stems remain at the entrance. What animal may live here? Kangaroo
rats eat the seed from plants found in the sand sheet and live in small
burrows to keep cool in the midday heat.
- The air is still. Around one side of a blowout grass plant a concentric
half-circle is carved in the sand. From which direction was the wind
blowing recently? From the direction opposite
of the half-circle.
- Roots up to 30 feet long sprawl across the sand, uncovered by the
wind. To what species of plant do these roots belong? Lemon
scurfpea. Why do these plants have such long roots? Lemon
scurfpea has long roots that help it draw from the limited moisture
deep in the sand, while the roots also anchor the plant in the ever-changing
sand.
- Ten-lined june beetles are herbivorous. On what species might the
beetle be found feeding? Ten-lined june beetles
are commonly found feeding on lemon scurfpea and other sand sheet plants.
- A small horned lizard with a sandy, mottled coloration scurries away
across the sand then stops and is motionless. Why did it stop fleeing
from you? It probably
instinctually stops and becomes motionless to allow its camouflage to
hide it from predators.
- At Great Sand Dunes, there are more than 1000 known species of insects.
Each have various ways of feeding. Do you think the endemic tiger beetle
is an herbivore, a scavenger or a predator? Predator.
- A circus beetle travels across the sand with no apparent primary direction.
It goes right, then left for a bit, then stops. Is this beetle traveling
aimlessly? No. What might the beetle
be doing? Scavenging for food.
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