CES Ecological Risk Assessment & Biodiversity

Question 1

What is an ecological risk assessment?

Accepted Answer

A process that evaluates the likelihood of adverse ecological effects from exposure to environmental stressors

Answer

Ecological risk assessment evaluates the probability that adverse ecological effects (such as species decline or habitat loss) may occur as a result of exposure to environmental stressors including chemical contaminants.

Question 2

What is a biological indicator (bioindicator) species?

Accepted Answer

An organism whose presence, abundance, or condition reflects environmental quality

Answer

Bioindicator species are sensitive to environmental changes and their health, population, or behavior provides information about the condition of their ecosystem, such as macroinvertebrates indicating stream water quality.

Question 3

What is the Endangered Species Act (ESA) designed to protect?

Accepted Answer

Species at risk of extinction and the ecosystems on which they depend

Answer

The ESA (1973) provides for the conservation of species listed as endangered or threatened, including the protection of critical habitat necessary for their survival and recovery.

Question 4

What is bioaccumulation in environmental science?

Accepted Answer

The gradual accumulation of a substance in an organism over time because the organism absorbs it faster than it can eliminate it

Answer

Bioaccumulation occurs when organisms absorb contaminants (like mercury or DDT) from water, food, or sediment faster than they can metabolize or excrete them, leading to increasing tissue concentrations over time.

Question 5

What is the difference between an endangered species and a threatened species under the ESA?

Accepted Answer

An endangered species is in immediate danger of extinction; a threatened species is likely to become endangered in the foreseeable future

Answer

Under the ESA, 'endangered' means a species is in danger of extinction throughout all or a significant portion of its range, while 'threatened' means it is likely to become endangered within the foreseeable future.

(CES) Certified Environmental Scientist Practice Test

(CES) Certified Environmental Scientist Practice Test

CES Ecological Risk Assessment & Biodiversity