Oliver et al (2004) Monitoring bleaching

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C. How long will it last and is it a recurring event? D. What are the ecological impacts on the reef system? E. Are adjacent human impacts causing or exacerbating the bleaching? collect similar data C1 • Carry out repeated observations (monthly) at selected key sites until bleaching disappears • Revisit these same sites if bleaching occurs in subsequent years • Ask local reef users for details of any previous bleaching events and record these on ReefBase Bleaching Questionnaires D1 • Carry out tasks in A1 • Conduct before (if possible) and after bleaching observations including mortality/recovery • General estimates of coral cover over time E1 • Carry out tasks in A1 • Note location, timing (onset, duration, cessation) and severity of local human impacts. • Carry out visual assessments of the severity of bleaching at 3 or more sites with and without such impacts • Ask other reef users to give you similar information • Get local weather data from Meteorological office on air temperature, sun hours, wind • consult with oceanographers regarding the circulation patterns, water exchange and any upwelling features in the area • compare bleaching records with published hotspots and degree heating weeks on NOAA’s website C2 • Carry out tasks in A1, A2 & C1 • Carry out the synoptic observations in A2 at monthly intervals till bleaching stops • Repeat these same observations for any subsequent bleaching events D2 • Carry out tasks in A1, A2 & D1 • monitor tagged corals – track mortality/recovery through visual estimates • measured estimates of benthic cover through time (transects/quadrats) E2 • Carry out tasks in A1, A2 & E1 • Detailed surveys at control and impact sites • Collate existing data on human impacts such as water quality, chronic disturbance from destructive fishing • Collect information on key environmental variables at impacts sites (turbidity, sedimentation, gross pollution indicators) • measure currents and tidal flow at key sites • acquire and analyse NOAA Local Area Coverage data to correlate bleaching records with thermal anomalies and degree heating weeks C3 • Carry out tasks in A1, A2, C1 & C2 • Repeat detailed observations in A3 at monthly intervals till bleaching stops • Repeat same observations for any subsequent bleaching events D3 • Carry out tasks in A1, A2, D1 & D2 • monitor tagged corals and quadrats – measure mortality and recovery using video or photographic records • measured estimates of benthic cover through time at higher taxonomic resolution (transects/quadrats) • transects of other macroinvertebrates • fish abundance and diversity surveys E3 • Carry out tasks in A1, A2, E1 & E2 • Detailed surveys at control and impact sites • Collate existing data on human impacts such as water quality, chronic disturbance from destructive fishing • Collect detailed data on all relevant environmental variables at impacts sites (turbidity, sedimentation, pollutants, nutrients, heavy metals etc) 10
Monitoring for different scenarios Since the level and extent of monitoring that can be conducted will depend largely on the time and resources available, and the objectives for the monitoring program, we have made recommendations based on 3 different resource scenarios, and 5 common questions/objectives related to bleaching. This provides a quick guide for developing a monitoring program. More details on how to design a program specifically tailored to your situation are given later in this protocol. Resource Scenarios Resources, in terms of funding, staffing and expertise, are all important constraints on the capacity of an organization or team to respond to a coral bleaching event. Recognising these constraints and working within them to maximise the quality and relevance of data is essential to a successful monitoring program. Three generalised resource scenarios are described below to guide you in selecting a suite of monitoring tools that are most suitable to your circumstances. Low Resources • No dedicated funds • No or limited numbers trained staff • Active volunteers available (with diving qualifications) • Concern over plight of local reefs and global Moderate resources • Some levels of dedicated funding available for bleaching work • Formal bleaching program exists or will be established • Trained staff available (or funding exists to train new staff) • Moderate level of logistic support (boats, computers, labs, scientifically qualified staff, good communications) High Resources • Substantial funding available • Dedicated bleaching program exists • Highly qualified scientific team • High level logistic support • Strong community and government commitment to program Outline of a typical monitoring plan The following example outlines how one might develop a program to address Questions A (Severity and Extent of Bleaching) & D (Ecological Impacts) with moderate resource levels. Prior to any bleaching being observed If your concern regarding the impacts of bleaching on a particular area has developed before any bleaching occurs, then it is important to carry out some surveys prior to bleaching, so that specific before and after comparisons can be used to gauge ecological impacts. • If visibility and local conditions permit, carry out manta tows of the overall area of interest to determine the distribution of habitats and the general characteristics of each habitat and zone. • Choose replicate sites which are representative of the area (if more than one habitat or reef zone is being investigated, choose replicate sites in each of these). Sites can be selected using the results of the manta tow or local charts or aerial photographs • Using timed swims (15 minutes around an area of about 50m x 20m) or manta tows (5 3 minute tows), estimate HCC, bleaching, anchor/blast damage at each area • Carry out line replicate LIT surveys at each site to measure % cover of principal benthos • Tag at least 20 corals at each site and record species, bleaching & mortality (presumably none at this stage) 11
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: which has very poor power to answer
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
Page 23 and 24: Colonies can be tagged using large
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

Oliver et al (2004) Monitoring bleaching

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