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CADDIS Volume 2

Learn About Responses

What Are Responses?

Responses are the biological results of exposure to proximate stressors.

  • Beyond this page, there is currently no response module in CADDIS.

How Do Responses Relate to Candidate Causes?

A candidate cause is a hypothesized cause of a specific environmental impairment, sufficiently credible to be analyzed in a causal assessment.

A candidate cause can be simply a proximate stressor (e.g., low dissolved oxygen concentration), that is, the stressor that is directly responsible for the observed biological response.

However, a candidate cause also may include more detailed information about the causal pathway, such as the mechanism or organismal level response that resulted in the ultimate response of interest (e.g., fish died due to asphyxiation). Including more detail may help identify ways to distinguish among different candidate causes included in the assessment.