Biological and economic feasibility of cultivating the mangrove cockle Anadara tuberculosa (Sowerby, 1833) in a shrimp farm reservoir with estuarine influence in Santa Elena, Ecuador

Abstract

The extraction of Anadara tuberculosa, a commercially valuable species in the tropical Eastern Pacific mangroves, presents significant ecological risks. To mitigate these risks, captive production of A. tuberculosa is crucial. This study examines the somatic conditions of laboratory-produced A. tuberculosa spat and their cultivation on a pilot scale in a canal-reservoir of a shrimp farm. Spat measuring 6.2 ± 0.9 mm were placed in baskets and cultured in suspension at a density of 776.6 ± 26.0 cockles (0.54 cockle per square centimeter). Environmental variables at the culture site were monitored. After 24 months of culture, the cockles reached a size of 44.7 ± 0.6 mm with a survival rate of 65.0 ± 0.6%. These production results were extrapolated to evaluate the economic viability of production in a shrimp farm canal-reservoir with estuarine influence. The proposed economic model yielded 325,000 market-ready Anadara tuberculosa mangrove cockles (in five culture cycles) with an estimated net present value (NPV) of $22,914.00. The modified internal rate of return (MIRR) reached 15.20 percent, and the cost-benefit ratio was $1.96. Economic projections indicate that the initial capital investment could be recovered within five years and one month (payback). This research provides evidence of the biological feasibility, including somatic growth, survival rates, and the relationship with environmental variables at the site, as well as the economic feasibility of cultivating A. tuberculosa in a canal of a shrimp farm with estuarine influence. The findings offer valuable insights for scaling up aquaculture production and initiating restoration processes for this species.

Keywords

• Shellfish farming
• Bioeconomy
• Suspended culture
• Environmental variables
• Cockle mangrove