Basking shark (Cetorhinus maximus) in Canadian Pacific Waters: recovery strategy: chapter 23

Appendix C: Threat attributes Terminology

Table 6: Details on Terms Used for Assessment of Threats to the Pacific Population of Basking Shark

Attribute	Level of Effect	Description
Extent	Widespread	Across the species range.
	Localized
	Unknown
Occurrence	Historical	Contributed to decline but no longer affecting the species.
	Current	Affecting the species now.
	Imminent	Is expected to affect the species very soon.
	Anticipated	May affect the species in the future.
	Unknown
Frequency	One-time
	Seasonal	Due to migration or particular seasons.
	Continuous	Ongoing.
	Recurrent	Reoccurs from time to time, but not on annual/seasonal basis.
	Unknown
Severity	High	Very large population-level effect.
	Medium
	Low
	Unknown
Causal Certainty	High	Evidence causally links the threat to stresses on population viability.
	Medium	Correlation between the threat and population viability, expert opinion, etc.
	Low	Assumed or plausible threat only.
Level of Concern	High	Overall level of concern for recovery of the species, taking into account all of the above factors.
	Medium
	Low

Terms were obtained from Environment Canada’s “Guidelines for Identifying and Mitigating Threats to Species at Risk” (Environment Canada, 2008).