White shark (Carcharodon carcharias) COSEWIC assessment and status report: chapter 11
Technical Summary - Atlantic Population
Carcharodon carcharias
White shark – Atlantic population: Grand requin blanc
Extent and Area Information
Population Information
Threats (actual or imminent threats to populations or habitats)
Commercial fishery bycatch worldwide, but only 13 recorded gear interactions from Atlantic Canada in 130 years; market for jaws, teeth, and fins; sport angling (not in Canada); coastal habitat modification, pollution.
Rescue Effect (immigration from an outside source)
Quantitative Analysis
Not done
Current Status
- COSEWIC: Endangered (April 2006);
- CITES Appendix II (October 2004);
- IUCN - Vulnerable
Status and Reasons for Designation
Status : Endangered
Alpha-numeric code: A2b
Reasons for Designation: The species is globally distributed in sub-tropical and temperate waters, but absent from cold polar waters; hence Atlantic and Pacific populations in Canada are isolated from each other and are considered separate designatable units. This very large apex predator is rare in most parts of its range, but particularly so in Canadian waters, which represent the northern fringe of its distribution. There are only 32 records over 132 years for Atlantic Canada. No abundance trend information is available for Atlantic Canada. Numbers have been estimated to have declined by about 80% over 14 years (less than one generation) in areas of the Northwest Atlantic Ocean outside of Canadian waters. The species is highly mobile, and individuals in Atlantic Canada are likely seasonal migrants belonging to a widespread Northwest Atlantic population; hence the status of the Atlantic Canadian population is considered to be the same as that of the broader population. Additional considerations include the long generation time (~23 years) and low reproductive rates (estimated gestation is 14 months and average fecundity is 7 live-born young) of this species, which limit its ability to withstand losses from increases in mortality rates. Bycatch in the pelagic long line fishery is considered to be the primary cause of increased mortality.
Applicability of Criteria
Criterion A: (Declining Total Population): Meets Endangered, A2b (population declines > 50% over the past 3 generations, using an index of abundance appropriate for the taxon, where the reduction or its causes may not have ceased or may not be understood).
Criterion B: (Small Distribution, and Decline or Fluctuation): Not met
Criterion C: (Small Total Population Size and Decline): Not met
Criterion D: (Very small Population or Restricted Distribution): Not met
Criterion E: (Quantitative Analysis): Not available.
1 The abundance trend estimate for the Northwest Atlantic (Baum et al. 2003) has been disputed (Burgess et al. 2005); however, the Marine Fishes Species Specialist Subcommittee considered the Burgess et al. (2005) critique to have been convincingly rebutted by Baum et al. (2005)
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