439%
200%
25% 25%
Biomass Density Size Richness
ECOLOGICAL EFFECTS OF MARINE RESERVES increases in size, diversity, abundance and biomass
SPILL OVER AND
EXPORT
Need for alternative approaches
16 PERCENT have adequate funds for effective conservation
PAPER PARKS protected areas often fail to protect
15 PERCENT of coral reef protected areas are adequately managed
06 PERCENT of coral reefs lie within adequately managed protected areas
Western Management Context
Sedentary or sessile inverts
URCHINS
SCALLOPS
ABALONE
TROCHUS
LOBSTER
CORAL
RARELY FISH
OR MULTI-
SPECIES
“fisheries gains from periodic closures will be marginal” “useful for maintaining population size but yield will decrease vs. continuous fishing”
Management challenges
Small-scale fisheries
MULTI-
SPECIES
MULTI-
GEAR
MANY
LANDING SITES
MANY
FISHERS
AITUTAKI AND RAROTONGA TROCHUS CLOSURES Cook Islands
Quota system Min (80mm) and max (110mm) size Varies
CONTROLS
Closed to trochus fishing Opening duration 1 day to 15 months
CYCLE
Approx annual harvest Men, women and children participate
HARVEST
National Ra’ui system Giant marine reserve Declining catches
OTHER
OTHER PERIODIC CLOSURES Sea cucumber, green snail, blood cockles, mud clams (and more trochus!)
Azafady, Madagascar St Luce area in the SE Second phase after pilot
LOBSTER
Roviara lagoon, Solomons Annual 8 month closures No harvest limits Mainly women and children
MUD CLAMS
Another BV project Rapidly growing, lives 3-5 years Longer closures: 5 months plus
MUD CRABS
Maluku province, Indonesia West Ngella, Solomons Varied closure periods
TROCHUS
Opening and closure cycles
A spectrum of different approaches
Open
permanently
Rotational
closure
Periodically
harvested
Closed
permanently
Periodically
closed
FIXED OR DYNAMIC Usually driven by community decision makers Cycles also sometimes influenced by supporting agencies To meet subsistence, cultural, commercial or ceremonial needs
OPENING AND CLOSURE CYCLES Highly variable
CEREMONIAL A savings bank with withdrawals during times of high demand. Feasts and festivals Often no explicit goals of long-term sustainable management
MED. TO LONG-TERM Many closures aimed at longer-term fisheries management goals Most commonly cited reason was to halt decline in fisheries resources
INDONESIA Maluku province: openings vary from a few days to two months Timing and duration based on informal stock assessments of by village council
OPENING AND CLOSURE CYCLES Examples of fisheries management/conservation goals
COOK ISLANDS Aitutaki trochus fishery Goals of sustainability and also maximising economic returns Harvest duration and timing based on western stock assessment methods
SOLOMONS Closures implemented to prevent overharvesting of Anadara granosa and Polymesoda sp. Rigid schedule with areas closed from September to April and harvested May to August
MANY FACTORS Species life history, habitat, ecosystem conditions etc Ranges from 1-3 year recovery following closure to 30-40 years Recovery often non-linear, especially with fish species
RECOVERY AND REPLENISHMENT DURING CLOSURE How quickly do fish and invert stocks replenish following cessation of fishing?
FISHER EXPECTATIONS For opening or level of exploitation may not coincide with sufficient recovery of some species But can work. Andara in Fiji 13-times higher in closed area and 5 times in adjacent areas. CPUE doubled
TYPES OF SPECIES Gen. more suited to short-lived, faster growing species E.g. Trochus – the most commonly managed with periodic closures in Pacific Not main mgmt tool? Cook Islands vs Solomons
WIDELY USED
BROAD BUY
IN
HARD TO
GENERALISE
VARIED
APPROACHES
SUMMARY Experiences from periodic fisheries closures
THANK YOU! Steve Rocliffe [email protected]
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