Browsing by Subject "Active coral reef restoration"

Tropical coral reefs are amongst the most biodiverse and productive ecosystems on Earth. In recent decades, coral reefs have suffered an unprecedented decline in habitat-forming hard coral cover due to anthropogenic stressors, with severe impacts on ecosystem functioning and the provision of ecosystem services. Some of the pressing issues that coral reefs are facing can be mitigated through active reef restoration, such as coral transplantation, which aims to increase the hard coral cover, biodiversity, and structural complexity of a reef site. Studies on the passive benefits that increase the natural recovery potential and resilience of coral reefs following active restoration efforts remain scarce. In collaboration with Indo Ocean Project, this study aimed to compare benthic recruitment patterns between three coral sites located within the Nusa Penida Marine Protected Area, Indonesia. The reef sites included a restoration site with gardened Acropora corals, a natural site, and a rubble site that could serve as a restoration site. The experiment was conducted using standardized settlement tiles to measure and observe various response variables as indicators for the natural recovery potential and resilience capacity of the reef. The sites were also surveyed for their benthic reef cover, structural complexity, and fish abundance and community composition. The research objective was to find out how benthic recruitment patterns differ between restoration and natural reef sites, and why. The results confirm that active coral reef restoration efforts induce co-benefits in the benthic environment through enhanced structural complexity, leading to subsequent increases in overall fish abundance and particularly the number of herbivorous fish, and thus to a lower density of turf algae. These are promising findings for the later development of the reef site. The results do not imply that restoration efforts directly translate into enhanced coral recruitment or increases in crustose coralline algae abundance. However, the plentiful supply of spats observed at the restoration site indicates that local coral recruitment can improve over time after the transplanted corals have healed from transplantation stress and become fecund. Finally, the current rubble area can be expected to function as a restoration area in the future, as it appears to be within the reach of coral recruits. This study demonstrates that active coral reef restoration can yield benefits for the whole benthic ecosystem, and thereby aid recovery and strengthen resilience at localized scales. Given the accelerated rate of coral reef degradation, regular monitoring of restoration success is crucial to avoid loss of information regarding the benefits of active coral reef restoration for the fragile benthic ecosystem.