1. Reflections on Loggerheads & Longlining
Tab B, No. 4(c)ii
Reflections on Loggerheads & Longlining
Trevor Kenchington
Gadus Associates

2. Loggerheads & Longlining
Recent trends in the loggerhead population
Contribution of reef-fish longliners to those trends
Policy goals, reference points, management targets and their absence

3. Loggerheads & Longlining
Recent trends in the loggerhead population

4. Loggerheads & Longlining

5. Loggerheads & Longlining

6. Loggerheads & Longlining

7. Loggerheads & Longlining

8. Loggerheads & Longlining
Nest Counts dropped about 45%
Period of decline uncertain

9. Loggerheads & Longlining
Nest Counts dropped about 45%
Period of decline uncertain
Probably reflects fewer adult females

10. Loggerheads & Longlining
Nest Counts dropped about 45%
Period of decline uncertain
Probably reflects fewer adult females
If so, at least partly a loss of adult females
Temporary increase in mortality above levels in 1990s
Decrease in recruitment to adult population may have contributed
Approximately 25,000 fewer adult females

11. Loggerheads & Longlining
Causes of the decline …

12. Loggerheads & Longlining
Causes of the decline are unknown

13. Loggerheads & Longlining
Causes of the decline are unknown
Decline seen in adult females
Does not necessarily indicate a decline in neritic juveniles

14. Loggerheads & Longlining
Contribution of reef-fish longliners to trends in the loggerhead population

15. Loggerheads & Longlining
Reef-fish longline fishery:
Takes ≈ 350 loggerhead per year
Kills ≈ 175 loggerhead per year
Kills ≈ 30 adult loggerhead per year
Sex ratio of takes and kills is unknown – could be 100% female

16. Loggerheads & Longlining
To order of magnitude, annual deaths of adults due to R-F longlining are:
1% of all adult deaths
0.1% of adult population
Over duration of decline in nesting, deaths of adults due to R-F longlining were:
0.1% to 1% of the 25,000 missing females, if deaths all female

17. Loggerheads & Longlining
All deaths due to R-F longlining are:
0.001% of all loggerhead deaths
<1% of anthropogenic deaths of neritic phase

18. Loggerheads & Longlining
Policy goals, reference points, management targets and their absence

19. Loggerheads & Longlining
Required percentage reduction in mortality …

20. Loggerheads & Longlining
Required percentage reduction in mortality:
What is the policy reference point ??