Hawaiian Fisheries Issues-2
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Transcript of Hawaiian Fisheries Issues-2
Hawaiian Fisheries Issues-2
• Guide for Nearshore Fishes-NMFS/DAR
• Lay Gill Net Restrictions
• Omilu Story
• Leave the Big Ones
• Deep 7 Bottomfish Closure
Reference
• Shomura, R. 1987. Hawaii’s Fisheries Resources Yesterday (1900) and today (1986). Southwest Fisheries Center Administrative Report 87/21. 14pp.
• SH319 H3 S56 1987
Case against Lay Gill Nets
• Lower biomass of reef fishes
• Fewer larger fish• History• Over-fishing
• Efficient• Left unattended• “disposable”• By-catch• Ghost-fishing• Substrate destruction
Survey Gauging Public Attitudes
• 96%: ocean/reefs are “very important”
• 65%: conditions are fair-poor & worsening
• 65%: recreational over-fishing = problem
• After learning the term– 94%: concerned over impact– 76%: support for ban/restrictions
Omilu
• DLNR: • Limit 10” (250mm)• LR50 • i.e., “legal”
• Tournament Results• Sampled 200 fish• Avg L = 350mm• 6 = sexually mature• All >600mm
Leave the Big Ones
• More fecund
• Larvae show better survival
• Birkeland, c. and P. Dayton. 2005. the importance in fishery management of leaving the big ones. Trends in Ecology and Evolution. 20(7):356-7.
Deep 7 Management
Bottomfish Fish SpeciesBottomfish
• Onaga• Ehu• Opakapaka• Kalekale• Uku• Hapu‘upu‘u• Gindai• Lehi• Butaguchi• Ta‘ape• White Ulua
Affected by closure• Onaga• Ehu• Kalekale• Opakapaka• Gindai
• Hapu‘upu‘u• Lehi
Closure
• May 15 – Oct 31 + ?? (Year by Year)
• MHI
• Deep 7 Species
• Prohibited: Fish for, Possess, Sell
• Release Incidental Catch
Shafer-style Management
• F- ratio (CFM / FM@SY)
• Weighted for 3 zones
• CPUE based on gear used over time
• Weighted for habitat in 3 zones
Biology of these Fishes
• Spawning
• Early life history
• Settlement
• Age at maturity
• Long life span
• Slow growth rates
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Chef Responses
Said customers are willing to pay more for Hawaii-caught bottomfish
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Said customers are not willing to pay more for Hawaii-caught bottomfish
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Said customers expect Hawaii-caught bottomfish to be less expensive in Hawaii relative to other fish dishes
9.5
Named bottomfish on list of “most desirable fish species” 77.3
Average percentage of meals that are fish 48.6
Average percentage of fish meals that are bottomfish 26.5
Average price of Hawaii-caught bottomfish dish $29.52
Average price of an imported bottomfish dish $28.46
Average portion size of a bottomfish dish 6.78 oz
Average product yield of whole fish (usefulness increases if stock made)
50%
Average days last month with bottomfish on menu 26.8
Average days last year with bottomfish on menu 325.4
Average percentage customers who are visitors to Hawaii 40.7%
Percentage of Wholesalers Interviewed
Said MHI are better in quality than NWHI bottomfish 100
Said NWHI and imported bottomfish are comparable in quality 33
Said imported better than NWHI bottomfish 33
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Pounds landed Imported snappers Price*
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hapu kali paka ehu onaga lehi gindai
Bottomfish CPUE in NWHI
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Current Status of Bottomfish in Hawaii’s Management Subareas
ZoneCPUE Ratio
(current/MSY)Effort Ratio
(current/MSY)
Threshold Above 0.7 Below 1.0
Hawaii, all areas combined
0.82 1.13
MHI 0.47 1.88
Mau Zone 1.01 0.96
Ho’omalu Zone 1.13 0.39
More Information
• Moffitt, et al., 2006. Status of the Hawaiian Bottomfish Stocks, 2004. PIFSC Admin. Report H-06-01.
• http://www.pifsc.noaa.gov/adminrpts/2000-present/PIFSC_Admin_Rpt_06-01.pdf
What are precious corals?
Colonial coelenterates living below the euphotic zone.
Valuable as a source of raw material for jewelry.
Main production centers at the present time are Taiwan and Japan.
Value of 1980 fishery is about $50 million [~50X stony coral imports]
Most precious corals live at depths of hundreds of meters, making harvest by other than remote methods impractical.
Precious corals are very much K-selected.
Skeletons are made of calcium carbonate, protein, or a mixture of the two. Color due to organic matter in skeleton.
Gold coral
Pink coral
Red coral
Black coral
Black coral
Maui Divers Star II
Scuba diver collecting black coral
Red Coral cabochon $1,865 Black coral pendant $570
Pink coral ring $150 Black coral earrings $1,165
History of Precious Coral Fishery
History of the fishery is one of boom and bust
Confined to Mediterranean until early 19th century
Started in Japan in early 1800’s, but did not flourish until after ~1870
Pacific fishery centered in far east until huge strike on Milwaukee Bank in 1965
Table 11.2. Growth rates of precious corals
Species Maximum height (cm)
Growth rate (cm y-1)
Location Reference
Corallium secundum 75 1.0 Hawaii Grigg (1976)
Corallium rubrum 45 0.5-2.0 Mediterranean Bauer (1909)
Antipathes dichotoma 250 6.4 Hawaii Grigg (1976)
Antipathes grandis 300 6.1 Hawaii Grigg (1976)
Antipathes salix 250 4.5 Caribbean Olsen and Wood (1980)
Table 11.3. Mortality rates of precious corals.
Species Locality Mortality (% per year)
Reference
A. dichotoma Hawaii 7 ± 2 (Grigg, 1976)
A. salix Caribbean 4 (Olsen and Wood, 1980)
C. secundum Hawaii 6.6 (Grigg, 1976)
Management of Precious Corals
• Susceptible to Over-exploitation
• Historical Attempts– Total Ban – Reserves– Limited Entry– Benign Neglect– Size & Weight Quotas
Age-frequency distribution of Maui black corals surveyed by Grigg in 1975
Information used to develop yield per recruit management model for Hawaiian black corals
Commercial landings of black coral in Hawaii and ex-vessel value of the corals.
Percentage of Maui Antipathes dichotoma colonies versus age from data reported by Grigg (2001). Straight line is a linear regression fit to the log-transformed data. The slope of the line is -0.098 per year.