Oliver et al (2004) Monitoring bleaching

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management of additional human impacts, and identify reefs which need to be protected since they are most likely to survive further warming and bleaching events. 2. Determine the factors that, in addition to increased sea temperature, play a major role in increasing (and decreasing) susceptibility to bleaching and subsequent mortality. 3. Develop a better understanding of which existing and new management practices can help reefs deal with the additional stresses of a warming ocean. 4. Raise awareness of the extent and urgency of coral bleaching as a possible threat to the future health and existence of coral reefs Why is a Protocol needed? Accurate and precise estimates of the severity, timing and spatial patterns of coral bleaching and subsequent mortality are essential if we are to gauge the level and immediacy of the threat, and to develop appropriate management actions to alleviate the ecological and social impacts. Unfortunately, lack of standardised protocols has led to a proliferation of survey methods, surveyed variables and variable definitions in different regions. Most reports are anecdotal and many are provided by people with limited training in quantitative ecological assessments. This makes comparison between areas exceedingly difficult. In addition there is considerable variability in the effectiveness of the various monitoring procedures which have been used. Consequently some surveys have not made effective use of personnel and time, and in some cases have collected data that are of limited use due to problems observational bias and lack of standardization between observers. There is a large number of global and regional monitoring programs aimed at assessing reef condition. However few of these have formal assessment and monitoring protocols, for bleaching as a key variable. Frequently, if it is mentioned bleaching is an added variable to be recorded in a comments section or as a simple statement of percentage affected. Those studies acquiring quantitative information use a wide variety of techniques that makes regional comparisons very difficult and any global synopsis unreliable. A standard protocol for assessment and monitoring would promote a higher quality of data, and a higher level of consistency between different reports thus enabling more reliable comparisons between studies. A standard protocol would also facilitate the ongoing development of a global database on coral bleaching events . Currently there is no easily accessible and practically oriented document advising people what they can and should do in order to better document and understand coral bleaching events. A flexible protocol that takes into account the varying levels of resources and expertise of different groups, and the different objectives is needed. This protocol aims to enable the further development and enhancement of the current global repository of standardised bleaching observations and data (ReefBase). Who will use the Protocol? It is assumed that this guide will be used by people wishing to record basic features of a bleaching event and to document overall impacts and possible relationships to causal factors. Two primary purposes, are to document global patterns, and to understand smaller-scale patterns and variations that may have local management implications. Thus this protocol is designed to produce more quantitative data on the global distribution, severity, and frequency of bleaching events so that more rigorous analysis of the relationship between coral reef status and climate change/global warming can be carried out. At the same time it is recognized that many managers also wish to investigate bleaching in order to determine what local management actions can be taken in order to lessen the impacts and increase the resistance and resilience of their reefs to large scale bleaching events. More detailed investigations into sub-lethal physiological impacts, subtle population ecosystem impacts etc are not covered here and constitute major dedicated research programs for which it is assumed specialized scientific personnel and specific research techniques will be involved 4
This protocol is designed to assist individuals and groups with an interest in the occurrence and impacts of coral bleaching on coral reefs. It offers advice to a range of people with varying backgrounds, skills, resources and interests. In general the protocol divides potential users in to the following groups. 1. Volunteer groups and recreational divers with an interest in reef conservation and threats 2. Scientists with formal training in marine science who are able to record information during field trips but whose primary focus is not coral bleaching 3. Members of dedicated volunteer organisations with an interest in monitoring coral reef status and threats (e.g ReefCheck) 4. NGO and Management agencies wishing to assess and monitor the impacts of coral bleaching and examine possible relationships between bleaching, and possible factors which could either increase or decrease the impacts to reefs 5. Scientist wishing to conduct formal assessments of coral bleaching who wish to ensure that their data will be comparable with other studies and who wish to contribute their summary data to a global database How should the protocol be used? We anticipate that this protocol will serve as: • a quick guide on what to do if bleaching is observed; • a guide on how to use time and resources most effectively to observe and record bleaching;. • an introductory resource on what bleaching is and how to recognise it; • an aid in making immediate reports on coral bleaching when seen in the field; • a guide for the development of structured and detailed assessments of bleaching as well as its causes and consequences . This protocol is a sourcebook for selecting an appropriate procedure from a range of possible procedures. Details on many of the procedures can be found in other documents and this protocol should be used in conjunction with GCRMN Methods Manual and other monitoring manuals. Where possible, formal design and planning of monitoring program should be conducted in consultation with scientists, managers, users and other relevant experts/stakeholders. The resulting data should be lodged in a properly maintained and backed up database, with summary data being provided to ReefBase. Data should be analysed and written up as a report as soon as possible and submitted it to GCRMN regional or national node coordinator, or ReefBase (GCRMN coordinators are listed at www.gcrmn.org). Quick Guide – Start Here This section should be used if you want some quick guidance on what to do if you have seen (or think you have seen) coral bleaching, and you want to know what to do and what your options are. In addition to providing an introduction on how to tell bleaching from other phenomena which result in white coral, this section takes you through the steps needed to decide what type of measurements and monitoring activities would be most appropriate for your circumstances. A basic assumption of this protocol is that, regardless of the specific reasons for studying bleaching, all readers will want to document the general extent and severity of bleaching as a first step. This section will first provide quick advice and pointers for documenting the basic features of a bleaching event. These steps should be conducted in all cases. It then proceeds to recommend various actions which could be followed depending on the additional questions and issues that are of interest, and the resources that available. How do I identify coral bleaching? Recently dead corals are also white, and can sometimes be confused with bleached corals. Bleached corals can be distinguished from dead corals by careful examination of the coral surface. Completely bleached corals look extremely clean and almost glow when seen underwater. (Figure 4). If the surface is sediment free, and if you can see minute transparent tentacles when you view the colony from the side, the coral is not dead. Dead, or dying colonies are unable to actively remove the sediment that rains down on all but the clearest reef environments, and so any accumulation of even small amounts of 5
Page 1 and 2: Draft A Global Protocol for Assessm
Page 3: Introduction Coral bleaching occurs
Page 7 and 8: and easily, even if only part of so
Page 9 and 10: which has very poor power to answer
Page 11 and 12: Monitoring for different scenarios
Page 13 and 14: Sites within a Location Locations w
Page 15 and 16: • The initially random selection
Page 17 and 18: Recommended Manta Tows The manta to
Page 19 and 20: Anchor damage: Pictures: Comments:
Page 21 and 22: Buddy: Vessel: Depth: Replicate: Be
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Page 27 and 28: WWF Bleaching Monitoring Program Ti
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Page 31 and 32: the event. Electronic salinity logg
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Oliver et al (2004) Monitoring bleaching

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