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Coral reefs experienced the third global bleaching event in 2015–2016 due to high sea-surface temperature (SST) anomalies. Declines in net carbonate production associated with coral bleaching are implicated in reef structural collapse and cascading impacts for adjacent coral reef islands. We present the first carbonate budget study of a reef platform surface (reef crest and reef flat) in the southern Maldives and the first record of upper reef flat condition in the central Indian Ocean post the 2015–2016 coral bleaching event. Scleractinian corals were the primary carbonate producers, with live coral cover averaging between 11.1 ± 6.5 and 31.2 ± 21.8% and dominated by massive corals. Gross carbonate production rates averaged 5.9 ± 2.5 G (kg CaCO 3 m 2 yr −1 ). Bioerosion was estimated at 3.4 ± 0.4 G, resulting in an average net carbonate production rate of 2.5 ± 2.4 G. Comparison of results with a study of the fore-reef slope highlights major differences in post-bleaching carbonate budget state between the fore-reef slope and the reef platform surface. The positive reef flat carbonate budget is attributed to the persistence of massive corals ( Porites spp. and Heliopora spp.) through the bleaching event.

SUMMARYThe short-interval fires required to promote grazing for large herbivores within the Cape Floristic Region World Heritage Site are detrimental to plant diversity. At the same time, longer interval fires significantly reduce graze quality. Conservation managers thus face an enormous challenge when the herbivores are also a conservation priority, since the competing conservation objectives are difficult to reconcile. Population growth rates of genetically important populations of endangered Cape mountain zebra (Equus zebra zebra) are low or declining following management focused on their fynbos habitat. Investigation of spatial and temporal habitat use and the diet of Cape mountain zebra, focusing on the use of land historically converted to agricultural grassland within fynbos in De Hoop Nature Reserve (South Africa), determined factors limiting populations and facilitated development of management strategies. Zebras selected grassland over other habitat types, despite grassland accounting for only a small proportion of the reserve. Grasses also made up the greatest proportion of diet for zebras throughout the year. Time spent on grasslands increased with grass height and was likely to have been influenced by grass protein levels. It is likely that grazing resources are a limiting factor for zebra, and so options for improving and/or increasing grassland at De Hoop should be considered. Translocation of surplus males to other conservation areas, reductions in other herbivore populations and targeted burns to increase grassland availability all offer short-term solutions. However, the acquisition of agricultural grassland adjacent to reserves is likely to be a viable long-term management strategy for this and other genetically important Cape mountain zebra populations. Low conservation priority habitats, such as farmland, should be considered for other management conflicts, as they have the potential to play a vital role in conservation.

The geomorphology and chronostratigraphy of the reef flat (including microatoll ages and elevations) were investigated to better understand the long-term development of the reef at Middle Island, inshore central Great Barrier Reef. Eleven cores across the fringing reef captured reef initiation, framework accretion and matrix sediments, allowing a comprehensive appreciation of reef development. Precise uranium-thorium ages obtained from coral skeletons revealed that the reef initiated *7873 ± 17 years before present (yBP), and most of the reef was emplaced in the following 1000 yr. Average rates of vertical reef accretion ranged between 3.5 and 7.6 mm yr -1 . Reef framework was dominated by branching corals (Acropora and Montipora). An age hiatus of *5000 yr between 6439 ± 19 and 1617 ± 10 yBP was observed in the core data and attributed to stripping of the reef structure by intense cyclones during the mid-to late-Holocene. Large shingle ridges deposited onshore and basset edges preserved on the reef flat document the influence of cyclones at Middle Island and represent potential sinks for much of the stripped material. Stripping of the upper reef structure around the outer margin of the reef flat by cyclones created accommodation space for a thin (\1.2 m) veneer of reef growth after 1617 ± 10 yBP that grew over the eroded mid-Holocene reef structure. Although limited fetch and open-water exposure might suggest the reef flat at Middle Island is quite protected, our results show that highenergy waves presumably generated by cyclones have significantly influenced both Holocene reef growth and contemporary reef flat geomorphology.