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Tab B, No. 4(c)ii. Reflections on Loggerheads & Longlining. Trevor Kenchington Gadus Associates. 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.
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Tab B, No. 4(c)ii Reflections on Loggerheads & Longlining Trevor Kenchington Gadus Associates
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
Loggerheads & Longlining Recent trends in the loggerhead population
Loggerheads & Longlining • Nest Counts dropped about 45% • Period of decline uncertain
Loggerheads & Longlining • Nest Counts dropped about 45% • Period of decline uncertain • Probably reflects fewer adult females
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
Loggerheads & Longlining • Causes of the decline …
Loggerheads & Longlining • Causes of the decline are unknown
Loggerheads & Longlining • Causes of the decline are unknown • Decline seen in adult females • Does not necessarily indicate a decline in neritic juveniles
Loggerheads & Longlining Contribution of reef-fish longliners to trends in the loggerhead population
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
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
Loggerheads & Longlining • All deaths due to R-F longlining are: • 0.001% of all loggerhead deaths • <1% of anthropogenic deaths of neritic phase
Loggerheads & Longlining Policy goals, reference points, management targets and their absence
Loggerheads & Longlining • Required percentage reduction in mortality …
Loggerheads & Longlining • Required percentage reduction in mortality: What is the policy reference point ??