Oliver et al (2004) Monitoring bleaching

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Colony level monitoring The following techniques should be used if you are asking a question which requires the fate of individual colonies to be tracked. Video recording along line transects or still images along a belt transect can also provide the relevant data for subsequent provided the imagery captures the same area of bottom on each visit. Tagged colonies have the advantage that they can be located in the field quickly without having to refer to the previous image. This allows tissue samples to be taken to track actual abundances of zooxanthellae (by clade if needed) or concentrations of Chlorophyll. Hybrid technique Currently WWF is employing a hybrid of LIT and Quadrat technique for some of its field projects. This method involves establishing a permanent 20m transect (marked at one end with a temperature data logger) and taking digital photographs of a 0.5 x 0.75m quadrat set along the transect every 0.5 m, alternating sides of the transect. This results in 40 photos. Additionally the quadrat is arbitrary tossed on the benthos in the area that would consist of the arc of the circle created by the transect line. Fifteen of these arbitrary tosses are made and a digital photo is taken of each. Digital photo resolution is maintained at 2272 x 1704 pixels using a 4 megapixel camera. Photos are then analysed by counting all of the colonies and assessing how many bleaching and to what degree. Tagged Corals The use of tagged colonies permits accurate assessment and ongoing monitoring of the health of specific colonies. In particular, the tracking of a population of corals from the onset of bleaching until mortality or full recovery has occurred, will provide the best measure of mortality that can be unambiguously related to bleaching. In other methods, mortality can only be inferred from a decrease in coral cover between sampling events. Tagged colonies are also particularly appropriate for investigating the relationship between the severity of coral bleaching and subsequent mortality/recovery, or the susceptibility of coral which have previously bleached and recovered to bleach in subsequent years (adaptation). Tagged coral are also essential for time series studies of physiological aspects of bleaching such as zooxanthellae density, changes in concentrations of UV protective compounds and responses and population shifts in zooxanthellae strains. If the above questions are of importance to the program at a particular location then one or more representatives sites should be chosen in which to tag several colonies for a range of species. It is recommended that a minimum of 20 (up to 50) colonies should be tagged for each species. If the objective of the study is to obtain detailed information on mortality and bleaching susceptibility of the coral community then species from several families should be chosen. In general, species from the most abundant families should be selected: Pocilloporidae, Acroporidae, Faviidae, Poritidae, but in areas where species from other families predominate, then these should also be tagged. Ultimately the number of species and fami lies tagged will depend on time and resources. It is better to sample adequately (~30) from a few species than to obtain inadequate sample sizes from a large number of species. During the initial survey (and at yearly intervals) the colony should be measured (length x height x width) and for all surveys its condition should be scored in terms of bleaching, and optionally disease and physical damage. A 4-point score should be used (Table 9 in Appendix 3) for bleaching, and a 3 point score for other types of stress. Where possible colonies should be tagged in a well defined area which can be easily resurveyed without having to swim over large distances. Colonies should be selected haphazardly and cover a range of sizes. If repeated samples are to be taken from the colony for laboratory analysis then larger colonies are essential. In order to facility relocation of tagged colonies, a rough map of the area should be drawn whilst underwater, showing major landmarks (e.g. large or unusually shaped colonies; sand patches; general reef features such as ridges, depressions, indentations and protrusion of the reef edge) in relation to each tagged colony. Alternatively, if visibility is usually low at the site, a nylon line can be strung from one colony to another to create a trail. This should be avoided in areas where other divers and tourists are likely to visit as it is both unsightly and likely to be removed. 22
Colonies can be tagged using large plastic tags. Cattle ear tags or pot plant labels are both suitable. Holes can be made in plastic tags using a small soldering iron or a skewer heated in a flame. The tags should be attached to the colonies using plastic coated wire or zip ties for branching colonies and galvanised roofing nails for massive colonies. For fragile plate species it may be necessary to attach the tag to the adjacent substrate, making careful note of it position in relation to the colony. Data management Once the data have been recorded in the field, it is critical that the information is transferred from the data sheets into the appropriate computer files as soon as possible (preferably the same or the next day). If there is a delay in transcribing the information to computer it is possible that ambiguous or missing information on the data s heet will be impossible to retrieve or remember. Data should preferably be entered directly into the MS Access database provided with this protocol. However MS Excel spreadsheets using the equivalent structure are also provided for users who are unfamiliar with MS Access software. MS Excel and dedicated statistical and graphics packages are best used to analyse the data. However, it is strongly recommended that the data is accumulated first into a single Access database covering all sites and times. Subsets of the data for particular sites or times can then be extracted for analysis by more specialised software. Data which are accumulated into a growing series of spreadsheet files becomes increasingly difficult to keep organised as the number of sites and samples grows. Once entered, the data should be printed out and checked for errors within a few days of recording the data (if longer you may forget important aspects which can help to resolve ambiguous entries). This should be done by having another person read out the data from the print-out while the original observer checks it with the entries on the datasheet. In addition it is worthwhile carrying out preliminary analyses to see if the summary data of % cover are within expected ranges. Cover values of more that 100% can then be checked for errors. Once the data are checked, the files should be backed up onto a separate disk clearly labelled and stored in a separate room or building. Summary data should be sent to collaborators and to ReefBase for general dissemination and inclusion in the global bleaching database. Literature Andrew, N.L. and B.D. Mapstone, (1987). Sampling and the description of spatial pattern in marine ecology. Oceanogr. Mar. Biol. Annu. Rev. 25 : 39-90 Berkelmans, R and J.K. Oliver (1999). Large-scale bleaching of corals on the Great Barrier Reef. Coral Reefs vol. 18, no. 1, pp. 55-60. Berkelmans, R., T. Done and V. Harriott (2002). Coral bleaching and global climate change :Current state of knowledge. CRC Reef Research Centre, Townsville, Australia. P6. Cesar, H., L. Burke and L. Pet-Soede (2003). The economics of worldwide coral reef degradation. Cesar Environmental Economics Consulting (CEEC), 6828GH Arnhem, The Netherlands. Coles, S.L. and B. E. Brown (2003). Coral bleaching-capacity for acclimatization and adaptation. Adv Mar Biol. 46:183-223. English S, C. Wilkinson, V. Baker (eds) (1997). Survey manual for Tropical Marine Resources ( 2nd Edition) Australian Institute of Marine Science. ASEAN-Australia Marine Science Project. 390 pp. Glynn, P.W. (1996). Coral reef bleaching: facts, hypothesis and implications. Global Change Biology 2:495-509. Hoegh-Guldberg, O. (1999). Climate change, coral bleaching and the future of the world’s coral reefs. Marine and Freshwater Research 50:839-866. Hughes,T.P., A. H. Baird, D. R. Bellwood, M. Card, S. R. Connolly, C. Folke, R. Grosberg, O. Hoegh- Guldberg, J. B. C. Jackson, J. Kleypas, J. M. Lough, P. Marshall, M. Nyström, S. R. Palumbi, J. M. Pandolfi, B. Rosen and J. Roughgarden (2003). Climate Change, Human Impacts, and the Resilience of Coral Reefs. Science 301: 929-933 Marshall, P.A and A.H. Baird. (2000). Bleaching of corals on the Great Barrier Reef: differential susceptibilities among taxa. Coral reefs, vol. 19, no. 2, pp. 155-163, 2000 23
Page 1 and 2: Draft A Global Protocol for Assessm
Page 3 and 4: Introduction Coral bleaching occurs
Page 5 and 6: This protocol is designed to assist
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: Buddy: Vessel: Depth: Replicate: Be
Page 25 and 26: Appendices Appendix 1. Data Forms S
Page 27 and 28: WWF Bleaching Monitoring Program Ti
Page 29 and 30: major effect not only on coral cove
Page 31 and 32: the event. Electronic salinity logg
Page 33 and 34: mainly for landscape/seascape conse
Page 35 and 36: Table 10. Benthic codes Level 1 Lev

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