Cesar2000-Economics of Coral Reefs.pdf

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greater willingness among environmental organizations to get involved in the LRFFT issue (Johannes & Riepen 1995; Pratt 1995; Barber & Pratt 1997a; Barber & Pratt 1997b). However, there is still considerable uncertainty about the extent of the coral reef degradation by cyanide fishing for live food fish. Laboratory experiments showed that exposure of zooxanthellate hard coral to a range of cyanide doses likely to occur during cyanide fishing results in coral bleaching or death of the polyps (Jones & Steven 1997). Bleaching of corals is caused by cyanide affecting the photosynthesis of the symbiotic zooxanthellae (Jones & Hoegh-Guldberg 1999; Jones, Kildea & Hoegh-Guldberg 1999). However, the toxicity of cyanide to corals under experimental conditions is, in itself, no proof for degradation on the scale of a reef. This is because the rate of coral loss due to cyanide fishing may be lower than the rate of natural coral growth, or it may be that under natural conditions cyanide is dissipated too rapidly by water currents to affect exposed corals (cf. Jones & Steven 1997). It is also unclear how reef degradation from the cyanide fishery for live food fish compares to the problem of overexploitation of target fish and to the problem of reef degradation caused by other destructive fishing techniques. Erdmann & Pet-Soede (1996, 1999) and others have previously suggested that the reef degradation from cyanide fishing may be wrongly emphasized, and that the more important issue requiring attention in the LRFFT is the potential for overexploitation of the target species (irrespective of capture technique). Mc- Manus, Reyes & Nanola (1997) have concurred that reef degradation from cyanide fishing in the LRFFT certainly is minimal compared to that wrought by blast fishing. Unfortunately, quantitative figures are generally lacking to help clarify this debate. One exception is the model of the effects of destructive fishing methods on coral cover in Bolinao (Philippines), which gives an estimate of a decrease of only 0.4% live coral cover per year due to destruction by cyanide fishing for ornamental fishes (McManus, Reyes & Nanola 1997). In an attempt to further clarify this debate and thereby better focus attention on the LRFFT issues most worthy of action, we have quantitatively estimated the reef degradation potential of cyanide fishing in the LRFFT in Indonesia by three independent methods, using both data from published reports and the authors’ collated experience with cyanide fishing. We hope that this opinion paper will stimulate additional information inputs that are needed to make decisions on how reef conservation dollars may best be directed. 2. CALCULATION OF THE EFFECTS OF CYANIDE FISHING ON CORAL REEFS One way to assess the degradation afflicted by the LRFFT is to estimate what amount of reef is being destroyed per fish caught with cyanide and multiply this with an estimate for the number of fish caught by the cyanide fishery. Even though this method requires the input of variables of imprecisely known value, this method should provide a crude approximation of the order of magnitude of reef degradation caused by cyanide fishing in the LRFFT. In the Spermonde Archipelago (Central Indonesia), on average 1 bottle (0.5–1 L) of cyanide solution is used to catch one fish (Pet & Pet-Soede 1999). We assumed this fully destroys live coral cover in an area of one square meter, both by poisoning of the coral polyps and by the fisher breaking away coral to extract the stunned fish. Based on personal observations on the catching procedure, this figure of one square meter live coral loss is probably an over-estimation for reefs with a relatively high cover of massive coral structures, as retrieving stunned fish that hide in the cavities under these massive structures will not require nearly as much breakage as retrieving fish that hide between branching corals. Additionally, squirted fish often flee their shelters, thus minimizing diver damage to coral when retrieving the fish (pers. obs.). Even the chemical damage per fish caught may be limited to an area smaller than one square meter (pers. obs., Erdmann & Pet-Soede 1996). Finally, this figure may result in an over-estimation of the reefdegrading capacity of the LRFFT because we assumed that the ‘killing area’ was fully covered with live coral. 70 PETER J. MOUS, LIDA PET-SOEDE, MARK ERDMANN, HERMAN S. J. CESAR, YVONNE SADOVY & JOS S. PET:
We used the one square meter figure anyway because we felt that management consequences of under-estimating the reef-degrading capacity of the LRFFT, i.e. allowing the cyanide fishery to continue, would be more severe than consequences of over-estimation, i.e. directing too many resources to the abatement of the cyanide fishery (precautionary approach). The estimate of reef area destroyed per fish caught, using Indonesia as an example, was multiplied by the number of fish caught per km 2 , per year, which was derived from: (1) the potential production and yield of grouper on pristine coral reefs where exploitation has only just begun, usually by large-scale operations (Pet & Pet- Soede 1999); (2) a mean observed effort of cyanide fishers times the estimated catch per unit effort (CpUE) in situations where reefs have already been exploited for some time, and where the most fish are caught by medium-scale operations (Pet & Pet-Soede 1999); (3) the volume of the LRFFT in Hong Kong, a significant proportion of which comes from Indonesia. In Indonesia live food fish is also caught by other methods, mainly hook-and-line and bamboo traps (pers. obs.; Erdmann & Pet-Soede 1999), but we adopted a precautionary approach by assuming that all fish were caught with cyanide. 2.1 Method I: Estimation based on the potential production and yield of groupers Estimates for the Maximum Sustainable Yield (MSY) of groupers in other coral reefs average 1000 kg per km 2 coral reef per year (Russ 1991; Jennings & Polunin 1995). If a pristine reef were to be exploited at a rate higher than this MSY, this would eventually lead to lower catch rates. We assumed an exploitation rate for the first year to be twice as high as the MSY, i.e. 2000 kg per km 2 per year, because the LRFFT tends to overexploit its fishing grounds (Bentley 1999). The average individual size of fish caught by large-scale cyanide fishing operations in relatively pristine areas has been estimated at 3.33 kg (Pet & Pet-Soede 1999), about 2 kg heavier than the overall average size of fish encountered in the LRFFT (Johannes & Riepen 1995). Hence, the total catch amounts to 600 fish per km 2 reef area, resulting in an estimated loss in coral cover of 600 m 2 each year. Expressed as a % cover change from the total surface area (%-points), this amounts to a loss in coral cover of 0.060%-points per year. 2.2 Method II: Estimation based on fishing effort and CpUE In Komodo National Park, a creel survey was conducted in 1997 to describe patterns in resource use. During this survey, which covered the full surface area of the Park and which was repeated 18 times during the 12-month period, the number of fishing operations using hookah compressors was recorded. Most, if not all, of the hookah compressor operations in the Komodo area use cyanide to catch live fish (pers. obs). The crew, consisting of ca. five persons of which two were hookah divers, operated from a motorized boat making trips of three days each. At that time, the ban on cyanide fishing was not enforced, mainly because it was usually impossible to obtain legal proof that cyanide was actually used. The number of cyanide operations in the Park seemed high compared to areas outside Park boundaries, probably because fishing opportunities within Park boundaries were still good. Within the boundaries of the Park, on average 3.2 medium-scale cyanide operations per day were encountered (Pet 1999). The coral reef area in the Park, estimated as a 50 m wide strip following the perimeter of all islands including their shallow reef areas, was ca. 17 km 2 . Therefore, the daily effort per km 2 coral reef averaged 0.19 operations. Estimates for the catch per trip in Komodo were not available, therefore a catch estimate was used from the Spermonde Archipelago, an area ca. 400 km from Komodo. In Spermonde, an operation of similar size as encountered in Komodo uses about 7.5 bottles of cyanide to catch an equal number of fish during each of the two days that fishing actually takes place (Pet & Pet- Soede 1999). Therefore, the total area potentially de- CYANIDE FISHING ON INDONESIAN CORAL REEFS FOR THE LIVE FOOD FISH MARKET — WHAT IS THE PROBLEM 71
Page 2 and 3:
Collected Essays on the Economics o
Page 4 and 5:
Table of Contents Acknowledgements
Page 6 and 7:
Foreword Corals and coral reefs hav
Page 8 and 9:
● ● ● ● assessing the threa
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fishing is lucrative from the indiv
Page 12 and 13:
Coral Reefs: Their Functions, Threa
Page 14 and 15:
Table 1. Ecosystem functions and co
Page 16 and 17:
Figure 1. Yield of Trochus Shells i
Page 18 and 19: Figure 2. Total Economic Value and
Page 20 and 21: Table 3. Total Net Benefits and Los
Page 22 and 23: Table 5. Valuation Techniques used
Page 24 and 25: people live from the Park, the high
Page 26 and 27: duction or logging) would have an e
Page 28 and 29: Hatcher, B. G., Johannes, R. E., &
Page 30 and 31: Thorhaug, A., (1992) “Oil Spills
Page 32 and 33: Authors Threats Mgt. Description Is
Page 38 and 39: Assessing the Benefits of Improving
Page 40 and 41: 2.2 Coral Reef Quality Change and t
Page 42 and 43: Five groups were given and the resp
Page 44 and 45: The total sample mean was similar a
Page 46 and 47: one of the five categories were nex
Page 48 and 49: 4.4 Protecting Rights and the Desir
Page 50 and 51: able for tourists versus locals was
Page 52 and 53: problem that where respondents are
Page 54 and 55: turists who regularly handle soil e
Page 56 and 57: expanding tourist industry based on
Page 58 and 59: ism and fisheries. Logging activiti
Page 60 and 61: Table 2. Fisheries gross revenue an
Page 62 and 63: an ‘Environmentally Critical Area
Page 64 and 65: 25,000 20,000 15,000 10,000 5,000 0
Page 66 and 67: sized animals — even at the most
Page 70 and 71: stroyed was 7.5 fish times 0.19 ope
Page 72 and 73: were affected by cyanide squirts fo
Page 74 and 75: Russ, G. R., (1991) “Coral reef f
Page 76 and 77: eefs that are not too remote, can n
Page 78 and 79: Table 2. Estimated net income (US$/
Page 80 and 81: Table 4. Results of base case and t
Page 82 and 83: ating the destruction of its coral
Page 84 and 85: creased. Besides these direct effec
Page 86 and 87: 3. ECONOMIC ANALYSIS: SOCIETAL COST
Page 88 and 89: 3.2 Case Study 2: Sri Lanka The soc
Page 90 and 91: A first difference between the two
Page 92 and 93: Coral Bleaching in the Indian Ocean
Page 94 and 95: leaching occurred in the Maldives,
Page 96 and 97: months after the coral bleaching ev
Page 98 and 99: Level of importance 35 30 25 20 15
Page 100 and 101: trols. What is useful from the data
Page 102 and 103: most disappointing: food and bevera
Page 104 and 105: REFERENCES Anderson, R. C., Waheed,
Page 106 and 107: also seem capable of providing many
Page 108 and 109: Table 1. Summary of Findings of Eco
Page 110 and 111: Table 2-A. Summary Table of Bioecon
Page 112 and 113: lation for the spawning stock abund
Page 114 and 115: 3.2.1 DENSITY-DEPENDENT MIGRATION M
Page 116 and 117: 3.2.3 DENSITY-DEPENDENT AND UNI-DIR
Page 118 and 119:
4.2 Habitat Protection A critical a
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REFERENCES Alcala, A. C., (1989)
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Russ, G. R., & Alcala, A. C., (1996
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poses of this review, the mechanism
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Supervision and training of labour
Page 128 and 129:
Table 1. Comparison of restoration
Page 130 and 131:
elating to the case studies. Recrea
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Value of reef products and services
Page 134 and 135:
Fitzharding, R. C., & Bailey-Brock,
Page 136 and 137:
1995). Global annual retail value o
Page 138 and 139:
Table 1. Market Prices in Hong Kong
Page 140 and 141:
2.3 Recent Trends The Asian financi
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destructive, since corals are often
Page 144 and 145:
(input factors are indicated by blu
Page 146 and 147:
Table 2. Challenges of grouper cult
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stages when natural mortality is hi
Page 150 and 151:
STRENGTHEN ENFORCEMENT AND MONITORI
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32 Several efforts along these line
Page 154 and 155:
Jones, R., (1997) “Effects of Cya
Page 156 and 157:
▲ An Economic and Ecological Anal
Page 158 and 159:
The Park was re-established and rev
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associated with dive tourism and th
Page 162 and 163:
Apparent stress threshold B A S 1 P
Page 164 and 165:
A Comparative Study of Socio-Econom
Page 166 and 167:
Table 1. Key Site Characteristics C
Page 168 and 169:
Level Target Respondent Information
Page 170 and 171:
Table 2. Variables Used in the Econ
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Table 3. Tied P-Values for Differen
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as, lagoons and coral reefs were pe
Page 176 and 177:
Table 5. Results of the Econometric
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ties may not reveal their true perc
Page 180 and 181:
Salafsky, N., Cordes, B., John Park
Page 182 and 183:
ICZM guides jointly the activities
Page 184 and 185:
such as alternative means of beach
Page 186 and 187:
2.3.2 CONTRIBUTIONS TO UTILITY —
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marginal benefit function, relating
Page 190 and 191:
the type of use, are not linked to
Page 192 and 193:
4. FUTURE DIRECTIONS FOR DECISION S
Page 194 and 195:
Huber, R. M., & Jameson, S. C., (19
Page 196 and 197:
Appendix. Economic valuation studie
Page 198 and 199:
Ecosystem and Approach ____________
Page 200 and 201:
Ecosystem and Approach ____________
Page 202 and 203:
Contemporary national development p
Page 204 and 205:
The PBPA contains four prominent ex
Page 206 and 207:
5. INTERACTIONS BETWEEN ECOSYSTEM S
Page 208 and 209:
Table 2. Categories of Ecosystems i
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MEY shows the enormous level of ove
Page 212 and 213:
the ecosystem together. The total (
Page 214 and 215:
▲ tourism, coastal protection and
Page 216 and 217:
has dramatically decreased from abo
Page 218 and 219:
seaweed per year is generating abou
Page 220 and 221:
Table 4. Current (1999) annual net
Page 222 and 223:
The essential activities that can e
Page 224 and 225:
their overall economic benefit to i
Page 226 and 227:
Private Sector Management of Marine
Page 228 and 229:
ety of important conservation and o
Page 230 and 231:
50 40 # incidents 30 20 10 0 J A J
Page 232 and 233:
● Investment security is reduced
Page 234 and 235:
onmental practices, and therefore t
Page 236 and 237:
7.4 NGOs Are Not Always Accountable
Page 238 and 239:
Sterner, T, & Andersson, J., (1998)
Page 240 and 241:
perfect but not completed and origi
Page 242:
Jeff Muller, Economist, World Bank,
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