Consequences of a Government-Controlled Agricultural Price Increase on Fishing and the Coral Reef Ecosystem in the Republic of Kiribati

<div><p>Background</p><p>Economic development policies may have important economic and ecological consequences beyond the sector they target. Understanding these consequences is important to improving these policies and finding opportunities to align economic development with natural resource conservation. These issues are of particular interest to governments and non-governmental organizations that have new mandates to pursue multiple benefits. In this case study, we examined the direct and indirect economic and ecological effects of an increase in the government-controlled price for the primary agricultural product in the Republic of Kiribati, Central Pacific.</p><p>Methods/Principal Findings</p><p>We conducted household surveys and underwater visual surveys of the coral reef to examine how the government increase in the price of copra directly affected copra labor and indirectly affected fishing and the coral reef ecosystem. The islands of Kiribati are coral reef atolls and the majority of households participate in copra agriculture and fishing on the coral reefs. Our household survey data suggest that the 30% increase in the price of copra resulted in a 32% increase in copra labor and a 38% increase in fishing labor. Households with the largest amount of land in coconut production increased copra labor the most and households with the smallest amount of land in coconut production increased fishing the most. Our ecological data suggests that increased fishing labor may result in a 20% decrease in fish stocks and 4% decrease in coral reef-builders.</p><p>Conclusions/Significance</p><p>We provide empirical evidence to suggest that the government increase in the copra price in Kiribati had unexpected and indirect economic and ecological consequences. In this case, the economic development policy was not in alignment with conservation. These results emphasize the importance of accounting for differences in household capital and taking a systems approach to policy design and evaluation, as advocated by sustainable livelihood and ecosystem-based management frameworks.</p></div

Elasticity of labor, income, and spending with respect to copra price¹.

1<p>Elasticities are calculated based on coefficient estimates from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0096817#pone-0096817-t004" target="_blank">Table 4</a> (for labor), <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0096817#pone.0096817.s005" target="_blank">Table S4</a> (for income and spending), and the distribution of household land under coconut cultivation. Robust standard errors. *p<0.1, **p<0.05, ***p<0.01.</p

Descriptive statistics of fishing and ecological survey data from Kiritimati (2007).

<p>Descriptive statistics of fishing and ecological survey data from Kiritimati (2007).</p

Map of the Republic of Kiribati showing study islands with villages and ecological sites.

<p>Map of the Republic of Kiribati showing study islands with villages and ecological sites.</p

Effect of the copra price increase on labor.

<p>Empirical estimates of the elasticity of copra labor (a) and fishing labor (b) with respect to the copra price for different levels of household land under coconut cultivation.</p

The government-controlled copra buying price () and the market fish price () (2001 AUD/kg)¹.

1<p>The government-controlled copra price is the same across households and the fish price is an average reported across households. Note that a regression of the natural log of fish price on the natural log of copra price that includes household and island fixed effects and clustered standard errors by household-village-year shows a small, positive relationship (0.14, <i>SE</i> = 0.05, p<0.001). A Spearman rank correlation yields the same results (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0096817#pone.0096817.s002" target="_blank">Table S1</a>).</p

Estimates of fishing labor and copra labor ¹.

1<p>Robust standard errors in brackets. *p<0.1, **p<0.05, ***p<0.01.</p

Descriptive statistics on household survey data and environmental data from four islands in Kiribati over the period 2001–2006¹.

1<p>The copra price is constant across households on the same island and is published by the government (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0096817#pone-0096817-t001" target="_blank">Table 1</a>) Abbreviations: prices (<i>p</i>), labor (<i>L</i>), income (<i>I</i>), household (HH). Subscripts indicate copra (<i>c</i>), fishing (<i>f</i>), or other (<i>other</i>) labor or income. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0096817#pone.0096817.s002" target="_blank">Table S1</a> for Spearman rank correlations between the copra price and the fish price and these variables.</p

Effect of the increase in the copra price and fishing on the coral reef ecosystem.

<p>Ecosystem models and estimates of elasticities from a path analysis of the effect of fishing on the coral reef ecosystem, occurring primarily through changes in (a) total fish biomass and (b) biomass of herbivorous fish only. * p<0.1, **p<0.05, ***p<0.01+ Based on econometric results. The relative size and color (black: positive, gray: negative) represent the magnitude and sign of the effect.</p

Supplement 1. Code for age- and stage-based population models of Lutjanus peru and four harvest scenarios run under four different conditions.

<h2>File List</h2><div> <p><a href="Age_based_model.txt">Age_based_model.txt</a> (md5: 79dcedfb16de00a82c617e05c87c17e7)</p> <p><a href="Stage_based_model.txt">Stage_based_model.txt</a> (md5: 7c91d0b1b3d3b431aabd1dfd6c7d14ff)</p> <p><a href="Harvest_scenarios_run1.txt">Harvest_scenarios_run1.txt</a> (md5: 271ed1e5a78e7935caa79c6210add541)</p> <p><a href="Harvest_scenarios_run2.txt">Harvest_scenarios_run2.txt</a> (md5: 42d7068eba16cc61e286416c1173367f)</p> <p><a href="Harvest_scenarios_run3.txt">Harvest_scenarios_run3.txt</a> (md5: 194496c7ee948907c47f3679f1945a19)</p> <p><a href="Harvest_scenarios_run4.txt">Harvest_scenarios_run4.txt</a> (md5: ad140c55ec41b584af2f9c553dd0966c)</p> </div><h2>Description</h2><div> <p>Age_based_model.txt Matlab script file for the age-based model.</p> <p>Stage_based_model.txt Matlab script file for the stage-based model. </p> <p>Harvest_scenarios_run1.txt Matlab script file to simulate the four harvest scenarios with market effects acting on catch per trip.</p> <p>Harvest_scenarios_run2.txt Matlab script file to simulate the four harvest scenarios with market effects acting on catch per trip with higher initial harvest rates.</p> <p>Harvest_scenarios_run3.txt Matlab script file to simulate the four harvest scenarios with market effects acting on catch per trip and new entrants.</p> <p>Harvest_scenarios_run4.txt Matlab script file to simulate the four harvest scenarios with market effects acting on catch per trip and new entrants with higher initial harvest rates.</p> </div