CORE CORE Natural Resource Management 2 — Questions and Answers
Question 1: What is a keystone species in an ecosystem?
- The most abundant species in a habitat
- A species that has a disproportionately large effect on its ecosystem relative to its biomass (Correct answer)
- Any species protected under the Endangered Species Act
- The top predator in every food web
Correct answer: A species that has a disproportionately large effect on its ecosystem relative to its biomass
A keystone species exerts an outsized ecological influence — such as the gray wolf reshaping vegetation through trophic cascades — far beyond what its population size alone would suggest.
Question 2: What management strategy is used to control invasive species in US public lands?
- Intentional introduction of competing invasives
- Integrated pest management combining mechanical, chemical, and biological controls (Correct answer)
- Allowing natural succession to eliminate invasives over time
- Fencing all invaded areas from all organisms
Correct answer: Integrated pest management combining mechanical, chemical, and biological controls
Integrated pest management (IPM) combines multiple control methods — including manual removal, targeted herbicide use, and biological controls — to manage invasive species cost-effectively.
Question 3: In the context of CORE education, what is a 'prescribed burn' and why is it used?
- A controlled fire set by managers to reduce fuel loads and restore fire-adapted ecosystems (Correct answer)
- An accidental wildfire that is allowed to spread without intervention
- A campfire safety demonstration for students
- A simulated fire drill in an outdoor classroom
Correct answer: A controlled fire set by managers to reduce fuel loads and restore fire-adapted ecosystems
A prescribed burn is a planned, controlled fire used by land managers to reduce hazardous fuel accumulation, promote native plant regeneration, and restore natural fire regimes.
Question 4: Which principle guides the selection of species for habitat restoration projects on US public lands?
- Use species with the highest commercial market value
- Prioritize native species that are genetically appropriate for the local region (Correct answer)
- Introduce species proven successful in international restoration projects
- Select species that require minimal water and maintenance
Correct answer: Prioritize native species that are genetically appropriate for the local region
Restoration ecology prioritizes locally sourced, genetically appropriate native species because they are adapted to local climate, soils, and ecological relationships.
Question 5: What does the term 'trophic cascade' refer to in natural resource science?
- The physical flow of water through a watershed
- Indirect ecological effects caused when a top predator regulates prey, which in turn affects vegetation (Correct answer)
- The seasonal migration pattern of fish species
- A government-funded land restoration cascade program
Correct answer: Indirect ecological effects caused when a top predator regulates prey, which in turn affects vegetation
A trophic cascade occurs when changes at one level of a food web (often the top predator) ripple down through lower levels, altering plant communities and ecosystem structure.
Question 6: What is the primary purpose of a habitat connectivity corridor in land management?
- To provide designated hiking routes through protected areas
- To link fragmented habitat patches so wildlife can move, breed, and maintain genetic diversity (Correct answer)
- To separate recreational zones from hunting zones
- To channel water flow between wetlands
Correct answer: To link fragmented habitat patches so wildlife can move, breed, and maintain genetic diversity
Habitat corridors connect isolated patches of natural habitat, allowing animals to move between them for foraging, breeding, and seasonal migration while maintaining genetic diversity.
CORE CORE Natural Resource Management 2
What is a keystone species in an ecosystem?