Reproductive potential and production role of artificial reefs-Southeastern Brazil

Artificial reefs (ARs) are used to increase fisheries productivity especially in areas with homogeneous seafloor, which are unfavorable for the development of commercial fisheries. The implementation of ARs increases the availability of resources, promotes protection against predation and represents a location for reproduction or nursery grounds for numerous fishes. Despite their recognized importance for fisheries, it is unclear if higher productivity in ARs are due to either the attraction of fish from adjacent sites or if these environments act as production areas. To clarify this relationship, it is essential to understand the role of ARs as breeding site and the use of this habitat during the initial stages of development of the associated ichthyofauna. The attractionproduction effect of a reef complex installed in 1996 along the northern coast of the state of Rio de Janeiro was assessed using as metrics the size classes and gonadal stage of fish collected in the ARs and in control areas (CA). Nine of the 10 main species collected in the region were more abundant in the AR than in the CA, including juvenile and adult fish. Mature and in maturation gonadal stages contributed the most for the dissimilarity between ARs and CA (~78%). The results indicate the use of artificial structures by individuals in initial stages of development and also adults toward reproduction periods. Therefore, the reef complex is probably functioning as a fish attractor and producer, expanding its value to broader spatial scales since these species can migrate to distant areas after becoming adult.

Automated summary

Artificial reefs play a significant role in increasing fisheries productivity by providing resources, protection, and breeding sites for fish. This study demonstrates that artificial reefs attract and support fish during both the initial stages of development and reproduction periods. This has important implications for understanding the functionality and value of artificial reefs in fisheries.