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Ocean warming is increasing the incidence, scale, and severity of global-scale coral bleaching and mortality, culminating in the third global coral bleaching event that occurred during record marine heatwaves of 2014-2017. While local effects of these events have been widely reported, the global implications remain unknown. Analysis of 15,066 reef surveys during 2014-2017 revealed that 80% of surveyed reefs experienced significant coral bleaching and 35% experienced significant coral mortality. The global extent of significant coral bleaching and mortality was assessed by extrapolating results from reef surveys using comprehensive remote-sensing data of regional heat stress. This model predicted that 51% of the world’s coral reefs suffered significant bleaching and 15% significant mortality, surpassing damage from any prior global bleaching event. These observations demonstrate that global warming’s widespread damage to coral reefs is accelerating and underscores the threat anthropogenic climate change poses for the irreversible transformation of these essential ecosystems.

The integrity of coral reefs has increasingly been threatened by human development and climate change. As a result, the concept of ecological resilience – an ecosystem’s capability to resist and recover from environmental stressors – has become an important aspect of coral reef conservation. In this study, coral reef resilience was quantitatively scored in Kenting National Park (KNP), Taiwan, using four different assessment frameworks: the first uses the opinions of local reef experts, the second includes metrics specific to the local reef context, the third combines the previous two approaches, and the fourth relies solely on ecological metrics from biodiversity surveys. To evaluate the accuracy of each assessment, the resulting resilience scores were compared with historical coral recovery rates, which served as a proxy for resilience. While each approach to measuring resilience has its merits and drawbacks, the picture of resilience became clearest when a few key indicators were included to reflect core ecosystem processes. Trends in resilience scores varied depending on the makeup of the assessment's indicators, and there was little correlation between the baseline metrics measured using different data collection methods. However, all resilience assessment trends indicated that KNP’s Nanwan area is high in resilience. This is likely due to the effects of local tidally-induced upwelling, which significantly relieve the growing thermal stress placed on surrounding coral communities. Ultimately, the most successful assessments were those that empirically quantified ecological processes and local factors with only a few indicators, rather than broader approaches that measured many indicators. These findings are particularly relevant for reef managers to consider as they develop and employ resilience-based management strategies.

Marine reserves (MRs) have emerged as a preferred method to protect coral reefs from overfishing and human disturbance. However, due to ineffective enforcement by governments, many MRs have been reduced to mere “paper parks” which fail to achieve conservation goals. This is especially true in countries such as China where compliance is low and resources dedicated to enforcement may be scarce. Privately managed marine reserves (PMMRs) may be effective in areas where government enforcement is lacking. To determine if PMMRs are a viable alternative strategy to protect coral reefs, we surveyed and compared fish assemblages and coral coverage in national MRs in Sanya, China to areas of reef privately leased to and managed by dive operators and hospitality industries. We found higher fish abundances and fish sizes in PMMR sites than in MR sites. However, while PMMRs are protected from fishing, other human impacts such as marine debris and illegal coral collection were evident in most tourist sites. Despite protection, long-term monitoring data of PMMRs revealed that in recent years, fish abundances have slightly recovered but species richness has not, indicating the need for a more comprehensive coral reef management plan. We strongly recommend coupling PMMRs with expertise supported regulations as an alternative coral reef management strategy in China.

Typhoons are a regular occurrence in tropical Taiwan. Local flora and fauna should be adapted to typhoons, however more severe storms in the past decade most likely due to climate change have caused an apparent impact on local ecosystems and diversity. Heavy rainfall from typhoon events has been associated with declines in density and biodiversity of low altitude freshwater fish. Montane streams on the other hand are assumed to be more resilient to typhoons as these habitats receive less washed-off pollutant and is buffeted by established vegetation. However, as access to isolated montane streams, especially after a typhoon, is difficult, the effects of typhoons on these habitats are rarely studied. In this study, we overcame many obstacles to survey montane freshwater fishes in Beikeng Creek shortly after a typhoon event. We demonstrated extreme changes in physical characteristics, but little changes in chemical characteristics of the stream. We also documented the absence of the endemic Rhinogobius rubromaculatus (red spotted goby) and the crashed population of Onychostoma barbatulum, (Taiwan shovel-jaw carp) after typhoon. Although these two endemic species are expected to survive in other unaffected montane creeks and streams in the vicinity, the dramatic decline in montane fish population in Beikeng Creek suggests that conservation management may need to be reconsidered to prevent possible extinction under increasing human and natural perturbations.