Reumo
Environmental preservation and sustainability can be considered social dilemmas in the interpretation that all involved would be better off if they cooperated to preserve the environment. However, if everyone does just that, someone else will be in an even better position to use other´s efforts solely to their advantage. In this context, and with the objective of promoting cooperation between individuals, some authors suggest the use of economic incentives to preserve a public good, such as the reward and punishment mechanism. The objective of this paper is to understand how cooperation between groups of professional fishermen and local indigenes works for the preservation of Itaipu hydroelectric power plant´s reservoir, considering the influence of economic incentives in the equation. Most articles that use field economic experiments analyze isolated groups, and it is difficult to establish a comparison. In order to analyze the cooperation of groups (Delaney; Jacobson, 2014; Shang et al., 2024) that reside near the reservoir of Itaipu hydroelectric power plant and obtain inputs for its subsistence, such as fish and water for consumption and farming, the economic behavioral literature was used (Robert; Broman, 2017; Zhang; Lu; Wang, 2024) and the experimental one (Croson; Gachter, 2010), with an emphasis on examining the cooperation of these groups and the role of the economic incentives in this process (Choi; Ahn, 2013; Lilliu et al., 2023). For the collection of data, the public goods game was proposed, adapted from Fehr and Gachter (2000), naming it this time as ‘reservoir game’, once the public good under analysis was the Itaipu power plant´s reservoir. The choice was made due to the fact that Itaipu hydroelectric power plant is the world´s largest energy producer, with its 20 units generating 700 MW, besides having a history of over a decade of joint work with the local fishermen and indigenes in the area by means of its sustainability programs (aimed at preserving the quality of the water in the reservoir, monitoring the ichthyofauna, campaigning to clean the reservoir, promoting the use of techniques for agriculture cultivation without the use of agrotoxics), and its reservoir providing water to the cities of the western region of the state of Parana. After a first sequence of six rounds, the experiment considered 2 options for the subjects to handle the outcomes between them: (i) the introduction of the possibility of a player punishing the others, and (ii) the introduction of the possibility of a player rewarding the others, in order to verify the influence of economic incentives in cooperation. The data was then statistically analyzed using descriptive analysis, multivariate regressions, and analyses of variance. After the statistical analysis, and with the results, we returned to the field to conduct in-depth interviews with the leaders of the fishermen and the indigenes groups, to better understand the findings. With the results, we returned to the field to conduct in-depth interviews with the leaders of the fishermen and the indigenes groups, to better understand the findings. As for the fishermen, it was observed that, although the reservoir represents the source of their livelihood, the contributions to the public good did not differ from the average results found in the experimental economic literature regarding the free riding behavior, which in turn was more tolerated than with the indigenes. The fishermen, partially influenced by the nature of their activity (executed in an extractive and individual manner) did not envision the need of cooperation, even if the public good in question represents their source of income. Tolerance to free riding behavior is due to the recognition of the material needs that other fishermen currently have. In addition, the financial condition of the fishermen, their sense of belonging to the group, and the delegation of responsibilities to the power plant as regards reservoir preservation actions, were the main topics debated to justify the findings of the experiment. The indigenes, in turn, presented a more cooperative behavior as regards the reservoir preservation. Their donations reflected part of the collective thinking, embodied in many of their daily activities, such as agricultural crops and the harvest season, when the indigenes forgo their individual chores to contribute to the group. As for the economic incentives, reward for cooperation proved to be more efficient than the use of sanctions for not cooperating, in both groups. Based on these findings, a number of determinants of cooperation are indicated, followed by a discussion of how many joint project initiatives could be facilitated, better managed, and even complemented, with a view to ensuring sustainability, and also reducing potential management costs, or costs stemming from free riding behavior actors.