Coral bleaching is expected to be severe in the Western Indian Ocean in early 2016 due to high ocean temperatures associated with a strong El Niño event and climate change. This document outlines a four-step plan for monitoring and responding to coral bleaching in the region: (A) Preparation, (B) Initial observations, (C) Monitoring bleaching and mortality levels, and (D) Communication. It provides guidance on monitoring methods at basic, intermediate and advanced levels depending on available resources and expertise. The goal is to track bleaching progression and engage stakeholders to facilitate response and reporting of impacts across the Western Indian Ocean.

1. Coral bleaching – 2016
Western Indian Ocean
David Obura
dobura@cordioea.net
www.cordioea.net/WIO-bleaching-2016
www.reefresilience.org/network

2. December January February March April May June
A) Preparation B) First observations C) Monitor bleaching, mortality, recovery
D) Communicate, report, relate respond
Coral bleaching – 2016
Western Indian Ocean
2016 may be a major bleaching year in the WIO
1) 2015 has been the hottest year ever globally
2) A very strong El Niño is underway in Dec
2015 – Jan 2016, in a very similar pattern to
that observed in 1997-98
3) Coral bleaching has been widespread in the
Pacific and Caribbean in mid-late 2015, which
suggests major bleaching likely in the
Western Indian Ocean in early 2016
Adding to the ongoing effort to prepare a
GCRMN report for the WIO in 2015-16, this is an
effort to increase the degree of reporting of
bleaching in the WIO in January – May of 2015,
and for this data to be reported with the GCRMN
Reef Outlook for the Western Indian Ocean, 2016
This is a very simple presentation of a
basic bleaching response plan for any
responders to undertake in the WIO
during 2016. The basic elements of a 4-
step response plan, and options for
bleaching methods are presented, to suit
different users’ needs, and assure
consistency among data to help with
regional reporting.
Key references and resources are listed
on the last page.
Detailed explanation of the methods is
available in the companion report.

3. December January February March April May June
A) Preparation B) First observations C) Monitor bleaching, mortality, recovery
D) Communicate, report, relate respond
A) Preparation
GUIDING QUESTIONS
• Why are you monitoring
bleaching?
• What staff or volunteers are
available to do monitoring?
• Do you have any funding to
support monitoring?
The more complex your answers are
to the above, the more detailed you
are likely to be able to collect data.
A) WHY?
Why are you monitoring bleaching? This should guide all
decisions in subsequent steps.
B) FIRST OBSERVATIONS
Who is on the water enough to provide reliable first
observations of bleaching? Approach them to do this,
and help prepare them.
C) MONITORING
What methods can you apply given your resources,
expertise, etc? Prepare the main stakeholders/individuals
who will do the monitoring.
D) COMMUNICATION
Who needs to know about the bleaching?
• Do the responsible agencies/authorities know
anything about bleaching?
• Do stakeholders (e.g. fishers, tourism operators,
hotels, etc.) know anything about bleaching
• Does the public know anything about bleaching?
• Is the media interested in/know anything about
bleaching?
DO THE FIRST COMMUNICATION BEFORE BLEACHING HAPPENS –
PREPARE ALL STAKEHOLDERS TO HEAR MORE NEWS FROM YOU
AS IT UNFOLDS.
If you need advice, consult
in the WIO group on the
reef resilience forum

4. December January February March April May June
A) Preparation B) First observations C) Monitor bleaching, mortality, recovery
D) Communicate, report, relate respond
B) First observations
.
.
GUIDING QUESTIONS
• Are you getting news/forecasts about the
progression of bleaching in the WIO?
• Are there people regularly on/over the reefs
that can alert you to the first signs of
bleaching? (e.g. dive/snorkel guides,
fishermen, MPA rangers, pilots in low-
flying/small planes)
To catch the first signs of coral bleaching you
need to have frequent visitors to some reefs that
can distinguish the first signs of bleaching from
other things.
BE WARNED!!
• http://coralreefwatch.noaa.gov/satellite/ for
global and http://1.usa.gov/1IWoSCq for
regional information.
• Visit www.cordioea.net/bleachingalert for
updated WIO alerts.
• Send an email to bleaching@cordioea.net to
receive email alerts every 2 weeks.
HOW TO OBSERVE FIRST BLEACHING
First observations of bleaching must be able to
reliably distinguish bleaching from other
conditions, such as dead coral skeletons, white
soft corals, etc.
Go to this page
for images
of bleached
corals.

5. December January February March April May June
A) Preparation B) First observations C) Monitor bleaching, mortality, recovery
D) Communicate, report, relate respond
C) Monitoring
METHODS
Based on your answers and capabilities, there are three
basic levels at which you could collect data. These are
described in detail in the accompanying GUIDE. Click on
the buttons below to see further details on each:
Basic – approximate estimate of proportion of
colonies affected at a site, little or no taxonomic
information.
Medium – visual estimates of coral colonies in
basic categories of normal/bleached/dead, genus
level identification
High – area-based censusof coral colonies in
continuous categories of normal/bleached/dead,
genus level identification, with or without colony
size information.
.
.
GUIDING QUESTIONS
• How often are you able to visit your sites, how
many sites do you have?
• Are there stakeholders who can help collect data?
• Do you have a system in place to manage/hold
the data?
• Do you have an existing monitoring programme
that this builds on?
To track the progression of coral bleaching you ideally
need to visit a site once very 2 weeks for as long as
the event lasts.
If you have different people/groups with different
abilities, you could plan for different levels of
monitoring to make the most of all contributors.
BASELINE
Ideally baseline conditions should be established at
monitoring sites, so as far as possible:
• Pre-select your sites (moderate/good corals)
• Apply a first set of measurements before bleaching,
then re-start the monitoring after 1st observations
of bleaching are confirmed.
FREQUENCY
• After the first bleaching survey, the method should
be repeated every 2 weeks until mortality has
ended.
• As many sites as possible should be done, the more
the better.

6. December January February March April May June
A) Preparation B) First observations C) Monitor bleaching, mortality, recovery
D) Communicating
METHODS
Based on your answers to the above,
Xxx more on this to be done … using recent
presentations and reef managers guide
.
.
GUIDING QUESTIONS
• How often are you able to visit your sites,
how many sites do you have?
• Are there stakeholders who can help collect
data?
• Do you have a system in place to
manage/hold the data?
To track the progression of coral bleaching you
need to visit a site once very 2-4 weeks for as
long as the event lasts.
If you have different people/groups with different
abilities, you could plan a coordinated response
to make the most of all contributors.
D) Communicate, report, relate respond

7. Monitoring methods
The next pages give details on recommended
monitoring methods at basic, intermediate and
high levels of expertise/effort.
The final pages show photographs of the typical
appearance of bleaching, and of other features
underwater that are white, but are NOT
bleaching.

8. Component Basic
Sampling location  Arbitrary, use 5-6 minute time swim for standardization
Spatial  Broad area of reef in view, perhaps 10-50 m along
Corals  All hard corals, key genera noted where possible.
Bleaching & mortality
observations
 None (<1%), low (1-10%), medium (10-50%), high (50-90%), extreme (>90%) bleaching.
 Can also use the same levels to estimate mortality.
Method – in situ  Estimate overall “look” of coral community, for all corals combined, and estimate proportion in categories
given above.
 Can do an overall count of colonies affected or not, to help estimation of %, but be aware of tendency to
focus on larger colonies.
 Note key features, such as principal genera affected, and estimate proportion for those, if possible
Method - photographic  Take 2-3 general views of the reef area, plus 10 or more vertical images 1m above substrate, separated by 2
or more meters.
 Two methods for analysis:
o proportion of corals is estimated as a % of coral community in each category in each photo, averaged
across the photos.
o using 5*5 grid of points (25 per frame), score number of corals in each category, add together for
total, and calculate % per category.
 Use a 1m long PVC stick/ monopod to help with camera-benthos distance, but try and keep it out of the
frame to maximize the utility of photos for other purposes.
Pros  Most accessible for users with low technical skills.
 Most rapid, can be applied over many sample sites in a short time.
Cons  Very open to personal bias in estimation of area affected and estimating impact.
 Minimum taxonomic resolution
Modifications  Can add detail on taxonomy (genera) and the proportion affected.
 Photos/video can be collected to verify estimates, or for experienced observers to assess basic bleaching
levels remotely.
Ideal target population  People ‘on the job’ (dive-masters, snorkel guides, MPA rangers/staff doing routine patrols), volunteers with
limited experience.
C) Monitoring method - BASIC

9. Component Medium
Sampling location  Arbitrary
Spatial  Multiple areas selected by eye.
 Sizes of 1-2 up to 12 m2 in size have been used.
Corals  All coral genera, no size
Bleaching & mortality
observations
 Fixed classes, e.g. normal, pale, part-bleached (10-50%), bleached (100%), part-dead, fully dead (recent
mortality only).
 More detailed categories have also been used: 0%, pale (any amount), <20%, 20-50%, 50-80%, 80-100%
bleached, recently dead.
Method – in situ  Score ALL coral colonies >10 cm diameter in the sampling area, recording their genus and condition. Take
care to not exclude normal colonies.
 If uncertain of genus ID, record (‘other’)
Method - photographic  Take 4-5 general views of the reef area.
 Take 20 or more vertical images 1m above substrate, separated by 2 or more meters – follow same
guidelines as for basic method.
 Analysis same as in basic category, including genus identification and greater replication.
Pros  Relatively rapid, allows for sample selection over wide area of reef.
 Can be undertaken more easily while doing other work.
Cons  Bias due to selection of sample points
 Bias due to preferential recording of bleaching bleached corals over normal ones, particularly for smaller
colonies
 Inadequate sampling of all corals - reefs can have >40 colonies/m2, so counting all colonies reliably in larger
samples (e.g. 2m radius) is unreliable and unlikely to be done consistently.
 Fixed classes for pale, bleaching and partial mortality ignore complex interactions between classes,
especially partial morality with partial bleaching.
Modifications  Disease and other conditions can be added.
 Use radial lines/quadrats to standardize sampling of unit areas.
Ideal target population  Management and monitoring programmes with semi-experienced staff/students/etc, but contributors are of
varying experience levels
C) Monitoring method - INTERMEDIATE

10. Component High
Sampling location  Arbitrary or fixed.
Spatial  Belt transects (e.g. 25*1 m)
 Due to the higher accuracy of this method, for repeated sampling it is advisable to fix a transect during the first
sample(s), using nails at the beginning and intermediate points (e.g. 5 m apart) in the transect.
 Ideally, record 2 or more transects per site.
Corals  Genus, with or without size
Bleaching & mortality
observations
 Continuous scale - proportion (%) of colony pale, bleached, dead.
 Include disease and other conditions.
Method – in situ  Score ALL coral colonies >10 cm diameter whose centers are within the quadrats/belts.
 Record their genus and % of each condition on the coral colony.
 If included, record size – IUCN method uses size classes of 11-20; 21-40; 41-80; 81-160; 161-320; and > 320 cm.
 If uncertain of genus ID, record (‘other’)
 If using fixed transects, only need to record all colonies on the first sample. After that, only record those colonies
that show some degree of bleaching/mortality (and disease).
Method - photographic  Take 4-5 general shots of the reef area,
 Take vertical images 1m above substrate along the full line of the transect. Make sure the images overlap enough
to show the continuity of the transect. This is unlikely to record the full 1m width of the transect, but the degree
of sampling should be comparable (e.g. of a 25*0.6 m belt).
 Analysis same as in medium category, with greater replication. If sizes are to be included, must use a length scale.
This can be a right-angle at the benthic end of the 1m spacer/mono-pod. Use a 20 cm length, marked clearly at
10 and 20 cm.
Pros  Most unbiased method to prevent over-counting of bleached and large corals (forces counting of normal and
small corals)
 Bleaching and mortality estimates are standardize to coral biomass (area) and density of corals on the reef.
 Accommodates variation in bleaching and mortality state of corals.
 Addresses size-dependent variation in bleaching
Cons  Time consuming.
 Sampling constrained to smaller areas of a reef due to the higher detail, so risk of bias due to spot-selection.
 Likely to be too detailed for most management applications, most applicable to research programmes.
Modifications  Multiple additions can be done –e.g. of disease, benthic cover, algae characteristics, etc. to extend the detail of
C) Monitoring method - HIGH

11. Examples of bleaching … images

12. Examples of other white things on
the reef – not bleaching …

13. References and resources …
Manual
Obura DO, xxxx and others?? (2016). Coral Bleaching Monitoring
Guide, Western Indian Ocean – 2016. Biodiversity Project, Indian
Ocean Commission, CORDIO East Africa. Xxx and others?
References in the main manual
Florida Reef Resilience Program (xx) Florida Reef Tract: Coral
Bleaching Response Plan
Marshall, P. (2003). Great Barrier Reef Coral Bleaching Response
Program. Great Barrier Reef Marine Park Authority, Australia.
Marshall and Schuttenberg 2006 – Reef Managers guide
McClanahan TR, Ateweberhan M, Graham NAJ, Wilson SK, Ruiz
Sebastián C, Guillaume MMM, Bruggemann JH (2007) Western
Indian Ocean coral communities: bleaching responses and
susceptibility to extinction. Mar Ecol Prog Ser 337: 1–13
Obura, D.O., and Grimsditch, G., (2009) Resilience assessment of
coral reefs- Assessment protocol for coral reefs, focussing on
coral bleaching and thermal stress. IUCN Working group on
Climate change and coral reefs. IUCN, Gland, Switzerland,
www.iucn.org/cccr/publications 70pp.
Oliver, J, P. Marshall, N. Setiasih and L. Hansen, 2004. A global
protocol for assessment and monitoring of coral bleaching.
WorldFish Center, Penang, Malaysia and WWF Indonesia, Jakarta.
35 p.
All the above references are available at www.cordioea.net/WIO-
bleaching
Websites
Resources associated with this guide:
• IOC project pages xxx
• www.cordioea.net/WIO-bleaching
• www.reefresilience.org xxxxx
NOAA Coral Reef Watch homepage:
http://coralreefwatch.noaa.gov/satellite/research
/coral_bleaching_report.php
Reefbase bleaching pages (not updated): xxx
… etc ...