Matthew Walker, Selma D. Mezger, Aiden Clarke, Igor Pessoa, Johanna Leonhardt, Ahmad Allahgholi, Jamie Craggs, Michael John Sweet
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引用次数: 0
Abstract
The capacity for natural coral reef recovery and the effectiveness of active restoration efforts are often contingent upon uncertain and understudied background variables, such as chronic predation for example. In the Maldives, small coral colonies (< 10 cm), primarily from the genera Pocillopora and Acropora (often found recolonising degraded reefs) are frequently predated on by the spiny cushion sea-star (Culcita schmideliana). Incidentally, these same corals (especially Acroporids) are often prioritised in active reef restoration practices. However, the level of risk these corallivores pose on restoration success has not yet been assessed. Here, we aimed to initially document the population densities of C. schmideliana on a degraded reef system in the Maldives (Kunfunadhoo, Baa Atoll). We then assessed their associated predatory effects on coral recruits and transplants, and explored the benefits of C. schmideliana removal on the survival of these corals. Population densities ranged between 1.2 and 3.3 individuals per 100 m2, which resulted in high predation rates on coral recruits (4 – 20%) and transplants (11 – 43%). Culcita schmideliana predation accounted for the majority of the documented mortality (85%). Where C. schmideliana were removed, a significant increase in survival for recruits (9% higher) and transplants (24% higher) was shown. Further observations linked a cessation of C. schmideliana removal to a significant rise in predation instances for previously protected corals (up to 52%). Our study therefore highlights the severe impacts of C. schmideliana predation and shows Culcita spp. population management as a viable passive solution for effective reef restoration.
期刊介绍:
Coral Reefs, the Journal of the International Coral Reef Society, presents multidisciplinary literature across the broad fields of reef studies, publishing analytical and theoretical papers on both modern and ancient reefs. These encourage the search for theories about reef structure and dynamics, and the use of experimentation, modeling, quantification and the applied sciences.
Coverage includes such subject areas as population dynamics; community ecology of reef organisms; energy and nutrient flows; biogeochemical cycles; physiology of calcification; reef responses to natural and anthropogenic influences; stress markers in reef organisms; behavioural ecology; sedimentology; diagenesis; reef structure and morphology; evolutionary ecology of the reef biota; palaeoceanography of coral reefs and coral islands; reef management and its underlying disciplines; molecular biology and genetics of coral; aetiology of disease in reef-related organisms; reef responses to global change, and more.