Design and Testing of an In-Water Nursery for Orphaned Corals on O’ahu’s South Shore

Abstract

In-situ coral nurseries have been implemented around the world and play a critical role in resource management and conservation. However, with Hawaiʻi’s strong currents, a coral nursery presents a new challenge for such a dynamic ocean landscape. In this work, an in situ marine structure was designed and tested towards deployment off the southern coast of Oʻahu, Hawaiʻi. This structure is designed specifically for the rehabilitation of orphaned corals of opportunity, i.e. non-fragmented coral colonies. It is safe, practical, and cost-efficient. In addition, it has been designed towards minimizing its potential environmental impact, meeting United States Army Corps of Engineers (USACE) regulations for permitting, and performing its desired functions under the unique conditions present in Hawaiian waters. Considering these design parameters, modeling software was used to draft a 3D design of the structure, which was then analyzed using finite element analysis software. This unique structure is suitable for mass husbandry and transplantation of coral colonies, using economies of scale to achieve impactful and systematic restoration. This type of in-water nursery will be the first of its kind in Hawaiʻi, and the world.