Trophic Level Food Web Case Study

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Date: «date»

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1 Riparian habitats are:

A High altitude mountain habitats .

B Terrestrial habitats adjacent to rivers and streams .

C Lake habitats .

D A forest-type habitat found in western North America .

E A type of grassland habitat .

2 What do you think Paul will find are the aspects of the ecosystem that most strongly affect the diversity of bird species found there?

A Available food for the birds .

B Number of predators of birds .

C Number of trees that provide nest sites for the birds .

D Something else .

3 At what trophic level are songbirds?

A Primary Consumer

B Secondary Consumer

C Primary Producer

D Secondary Producer

4 What other organisms share a trophic level with songbirds?

A Coyotes

B Rabbits

C Aspen

D Mule Deer

E Beaver

5 The one kind of feeding relationship NOT illustrated in the food web is . . .

A Carnivory

B Herbivory

C Omnivory

D Cannibalism

E All the above relationships are illustrated

6 What does this FUNCTIONAL food web suggest about other organisms that may influence SONGBIRD population growth?

ANumbers of insects will substantially affect songbird populations .

BNumbers of willows and aspens will substantially affect songbird populations .

CNumbers of moose and elk will substantially affect songbird populations .

DMore than one trophic level will affect songbird populations .

E More than one of the above answers is correct .

7 Look at your food web diagram . If bottom-up control explains the size of songbird populations in Paul's riparian habitats, which graph best illustrates the critical population interactions?

8 Look at your food web diagram . If top- down factors control songbird populations, increasing which population do you predict would result in reduced songbird populations?

A High hawk populations

B Low hawk populations

C High moose populations

D High coyote populations

E Low coyote populations

9 The summary data didn't reflect differences Paul thought existed between his sites, so he looked more closely at his first year data . What conclusions about trophic effects can you draw from these data?

A Hawks have a top-down effect on songbirds .

B Willows have a bottom- up effect on songbirds .

C Insects have a bottom-up effect on songbirds .

D Moose have a top-down effect on willows .

E More than one of the above statements is a valid conclusion.

10 If moose affect willows, what impact on songbirds might be expected if moose populations increase? Look at your food web diagram .

A No change in songbird populationsB Increase in songbird populations

C Decrease in songbird populations

11 Paul thinks the moose-willow feeding interaction may affect the songbird populations . What non-feeding relationship in this community likely provides a mechanism by which moose affect songbird populations?

A Willows provide habitat and food for insects .

B Willows provide nest sites for birds .

C Moose waste adds nutrients to soil for the willows .

D Grasses provide material for bird and rabbit nests .

12 Shortly after Paul's first year of research, the first wolves were reintroduced to Yellowstone NP . How do you predict wolf reintroduction will affect songbird abundances?

A No change in songbird populationsB Increase in songbird populations

C Decrease in songbird populations