Proceedings of the Hawaii Coral Reef Monitoring Workshop – A tool for management. June 9-11,
1998. East-West Center, Honolulu, HI, USA.

What is the Purpose of Monitoring Coral Reefs in Hawaii?
Gregor Hodgson
Institute for Environment and Sustainable Development
Hong Kong University of Science and Technology
Clearwater Bay, Kowloon, Hong Kong<rcgregor@ust.hk>
Abstract
Before embarking on an ecological monitoring program, it is important to define theobjectives. The monitoring program can then be designed to fulfill those objectives. If
the purpose of monitoring is to assist resource managers, then a number of importantquestions should be considered during the design process including: 1) Who is going todo the monitoring and analysis, and what resources are (should be) available to support
it? 2) What natural and anthropogenic impacts are expected? 3) What naturalvariation in population parameters is expected? 4) What are the spatial and temporalscales of interest? 5) What variables (population levels, physiological status) are mostimportant to monitor from economic, social, and ecological perspectives? 6) Whatvariables can be monitored most efficiently in terms of useful information content perunit of monitoring effort? 7) What quantitative and null hypotheses can be used to test
whether a change is statistically significant? 8) What sampling design (temporal andspatial) including controls will be used? What statistical procedures will be used to test
the hypotheses? 9) What level of change is ecologically significant? 10) How will thecause of a significant change be determined? 11 ) What options are there formanagement action in response to a change, and what level of reef change should
trigger a change in management? 12) What quality assurance procedures are needed toensure that the data are correct? 13) What are the deficiencies of the design and how
will they be dealt with? Once these questions have been answered, a useful, costeffective monitoring program can be set up.
Introduction
Monitoring coral reefs is one type of Environmental Monitoring and Audit (EM&A), asystem that has evolved from environmental impact assessments (EIAs). The design ofa practical, useful EM & A plan involves art as well as science. There is no one correct
design, and there are many incorrect ones. A poorly designed EM & A plan can be
costly, wasteful, and may produce meaningless, misleading or incorrect results. To
avoid these pitfalls, it is essential to follow a rigorous design process that includes
consideration of a series of questions about the purpose and content of the project, as
well as a detailed review of available data and/or a pilot study to determine key factors.
As part of the EM&A plan, it is essential to include a flexible Action Plan which lists
what specific activities may be undertaken if a particular change is detected in theecosystem. It is important to integrate the EM&A plan with a more generalmanagement plan for the area.
Surprisingly little advice has been written about the subject of EM&A plan design,
particularly with respect to coral reefs. The subject of sampling design and statistics for1environmental biologists is thoroughly covered by Green (1979). The application of
EIA techniques to coastal areas is reviewed by Carpenter and Maragos (1989). Oxley(1997) has presented a summary of important design considerations with respect tocoral reefs. Short but useful guidance is given in the UNEP publication “Staff Training
Materials for the Management of Marine Protected Areas,” especially Training Session
8.2 (Kenchington and Ch’ng, 1994). The monitoring program used in the US Virgin
Islands is described by Rogers (1993) and that on the Great Barrier Reef is explainedin Oliver et. al, (1995). An extensive menu of marine monitoring methods for both
reefs and non-reef areas in the Pacific is provided in English et al, (1997). The use ofvolunteers and non-professionals in monitoring programs was reviewed by Wells(1995). A concise set of methods designed to be taught to dive instructors has beendeveloped by McManus et al. (1997).
There is a great deal of literature available on ecological sampling design and statisticalanalysis. Numerous publications by A.J. Underwood and colleagues at Sydney
University have covered the statistical aspects of using complex sampling designs suchas BACI, that meet the assumptions of parametric statistics, particularly ANOVA (e.g.
see Underwood, 1993). As an alternative, R.M. Warwick and colleagues at Plymouth
Marine Laboratory, UK have promoted the use of multivariate statistical designs,
particularly ordination. Their journal publications and the instruction manual for their
Primer statistical package contain much useful advice (Clarke and Warwick, 1997). To
determine which EM&A design will be most suitable for Hawaii, it is helpful toconsider possible answers to the following questions.
Who should design a monitoring plan for Hawaii?
There are major differences in philosophy and practice between managers andacademic scientists. Some of these differences are shown below in Table 1.
Table 1. Different perspectives on research and monitoring (after Kenchington andCh’ng, 1994)
Subject area
Main goal of work
Timeframe
Basis for decisions
Expectations
Focus
Bias in decision-making
Mode of operation
Constraints

Academic scientist’s view
New scientificunderstanding
As required to get answer“Good” data
Additional study always
neededDetails
Rely on biology, chemistry
and physics
Do research to gain
knowledge
Not enough data

2

Manager’s view
SolutionsShort-term
Data, values, laws,
opinions, costs
Definite answer required tomake decisions
Broad brush
Include politics and socioeconomics
Do research to support
decisions for management
Data, politics, socioeconomics, cost

Because of these fundamental differences, scientists are not the best people to design amonitoring plan. The monitoring plan should be designed as part of an overallmanagement plan that serves the needs of the entire community. The plan should bedesigned by resource managers who take advice from a multidisciplinary advisorycommittee including academic and non-academic scientists, businessmen, and otherstakeholders in the community.
What types of monitoring are needed in Hawaii?
There are two types of monitoring that could be useful in Hawaii: 1) intensive detailed,species-specific monitoring carried out by well-trained technicians and marine
scientists; and 2) less intensive, less specific, community-based monitoring carried out
by trained members of the public, and led by a qualified marine scientist. The Reef
Check program is an example of the second type of monitoring (Hodgson, submitted).
In addition, traditional basic and applied coral reef research should continue to be
carried out by academic and other scientists. Often, the lines between these three typesof field work will be indistinct, therefore, the more communication between thesedifferent groups, the less overlap and waste will result.
Who should do the monitoring and analysis?
There is never sufficient funding to carry out all of the monitoring and analysis thatwould provide a complete picture of natural resources in a timely manner. Because
coral reefs are found almost everywhere in Hawaii, and because they are subject toheavy use by local communities, there are hundreds of individual coral reef areas in
Hawaii that deserve to be monitoring stations. But the state alone does not havesufficient technical staff nor funds to monitor such a large number of sites even once
per year. Given the current economic crisis in Hawaii, it is a good time to consider
how to do more with less. The types of monitoring that can be handled by different
types of surveyors, their advantages and disadvantages are given in Table 2.

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Table 2. Types of monitoring carried out by different grades of surveyors and their positive and negative attributes
Surveyor

Can carry out:

Limitation

Advantage

Academicscientist

Detailed species-specific census and stock
assessment, ecological assessment,
problem solving, analysis with respect todiverse academic sources of information

•
•
•

•
•
•

High quality results
Medium cost
Managers get latest reports fromacademic research•••Medium to high quality results
Results produced on time, within budget
Willing to offer conclusions based on
available data
May keep track of latest reports fromacademic research
Familiar with QA
Medium to high quality results
Results buried under paperwork
Willing to offer conclusions based on
available data
Familiar with QA
Medium to high quality results
Results on time
Familiar with QA•

Commercial
consultant

Detailed species-specific census and stock
assessment, ecological assessment,
problem solving, analysis with respect todiverse academic sources of information•••

Slow, and often not available when needed
May be reluctant to come to a conclusion
Little incentive to participate unless allowed topursue a basic research objective
May need different specialists for e.g. corals
and fishOften unfamiliar with QA
May need different specialists for e.g. corals
and fish
Expensive•

State seniorscientist

Detailed species-specific census and stock
assessment, ecological assessment,
problem solving, analysis with respect todiverse academic sources of information••

Usually too busy to get in the water
Little time to read academic journals

State juniorscientist/
technicians

Family-level and some detailed speciesspecific census and stock assessment,
ecological assessment, some problem
solving••••

Community
members(scuba divers
and snorklers)

Family-level and some detailed speciesspecific census and stock assessment

•
•
•
•

Too few to do all the work required
Many other duties
May lack of experience to interpret data
May not be up to date on latest ecologicaltheories
Require training
May require team scientist during surveys
Different levels of experience
Available only at certain times

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•
•
•
•
•
•
•
•
•
•
•

Medium to high quality results if survey isappropriate for skills level
Cheap, enthusiastic, good PR
Participation gives a sense of ownershipsupports marine conservation

A sensible approach for Hawaii is to design a monitoring program with different levelsof detail and intensity that can be carried out using a combination of the above types ofsurveyors. Given the numbers of recreational divers, and the strong support for marine
conservation in Hawaii, the state is in a far better position than anywhere else in theworld to carry out a cost-effective, detailed, multi-tier monitoring program involving
scientists, state employees, students, and recreational divers. While high-intensity
monitoring has one goal – to produce high-quality data, community-based monitoring
has a second goal, and that is, to increase support and understanding for marine
management. Successful implementation of a community-based monitoring program
such as Reef Check, can increase public support for government management
programs and has the potential to dramatically decrease the costs of enforcement.
Community-based management of marine resources is a Polynesian tradition that was
only recently lost in suburban Hawaii.
What resources are available to support the monitoring program?
The state has limited resources available to support a coral reef monitoring program.
By using volunteer labor in combination with state workers, consultants andacademics, the value of the state’s investment in monitoring and management will be
increased many fold. In addition, by using volunteers, particularly students orcommunity groups, it is possible to attract cash and in-kind cost-sharing for training,surveys etc. In 1997, the first Reef Check global coral reef survey was carried out on acompletely volunteer basis and an estimated US$2 million was provided in cash, inkind services (hotel rooms, airplane tickets, boat transport), materials, and labor. By
using an “adopt-a-reef” program and other community involvement methods,
volunteers can play a major role in monitoring and management of Hawaiian reefs. By
joining in the Reef Check annual global survey, participants also will be able to quickly
see how “their reef” compares to others around the world, and following repeatedsurveys, whether management measures are working or not. Details of the program
may be found at: www.ust.hk/~webrc/ReefCheck/reef.html.
Given the large numbers of people who could potentially be involved in communitybased monitoring programs in Hawaii, it will be useful for the state to collaborate with
one or more NGOs such as The Nature Conservancy, to handle the coordination
aspects of the training and surveys. The high number of potential teams in Hawaii
would allow a large number of sites (hundreds) to be surveyed at least annually. This
organizational structure then will free up academic and other scientists, and state staff
to carry out and manage the more intensive sampling at selected sites of high interestand to handle the analysis and interpretation of results. The latter operation should be atask for a multidisciplinary team from academia, commercial consulting and thegovernment. An external reviewer from outside Hawaii would also be a valuable
investment.
What are the temporal and spatial scales of interest?
Although some island residents may occasionally feel trapped, Hawaii covers a large
area. How will it be possible to capture sufficient information about reefs throughout
the state with the limited resources available?

5It is safe to assume that the scale of interest to most people is the condition of theirfavorite dive or fishing spot. Few people living in Makaha will be overly concerned
about the reefs in Poipu. While it would be a mistake to only choose monitoring
stations based on usage, it is not possible nor sensible to monitor equally everywhere.
One approach to designing the monitoring station network is to first mark up a map
with high priority sites, and then medium and low priority sites. By using a tiered
monitoring design (see below) with different levels of intensity at different locations,the high intensity stations can be located at high priority locations, with lower intensity
stations at medium and low priority sites.
What natural and anthropogenic impacts, and what natural variation in
population parameters are expected?
For each study site, it will be important to carry out a mini-EIA type review todetermine what natural and anthropogenic changes are expected to occur, and to what
extent they might be expected to affect populations of ecologically or socioeconomically important organisms. This information should be reviewed for the wholestate. The review will help determine what parameters (physical, chemical andbiological) should be monitored. It will be useful to have a set of “core methods” to be
used at every site so that comparisons can be made, and “additional methods” can be
added at sites with special conditions.
All available literature should be reviewed to seek information on natural population
variation over time. Populations of marine animals are notoriously unstable and mayvary dramatically over time due to natural events such as poor recruitment, storms etc.
Without knowing what level of variation is to be expected over say, a ten-year period,
it is difficult to design an Action Plan that is based on changes in populations.
What variables are most important to monitor from economic, social, andecological perspectives? What attributes are most important to monitor(population levels, physiological status of organisms)?
It will be important to include a basic set of physical and chemical indicators of thestate of the reef environment in the monitoring program because when a change
occurs, that data can make it possible to rule in or out certain causes. Typical usefulparameters for intensive monitoring stations would include temperature, salinity, pH,turbidity and oxygen. These measurements can be made with a standard commercial
probe and can now be supplemented with an automated chlorophyll and nutrient
analyzer.
There are thousands of species of animals, plants and other life forms on Hawaiian
coral reefs. Choosing a core set of “indicators” is essential for a cost-effective andmeaningful monitoring program. Some potential indicators may be importanteconomically, but less important ecologically. For example, it can be imagined thatsome species such as the ulua or lobster could be harvested down to low levels on areef without having much impact on other parts of the reef system, perhaps due to a
related species moving in to take up its ecological role. But a low level of ulua or
lobster could have a significant economic impact on fishermen. In Hawaii, it will be6

useful to include both ecologically and economically important organisms in the list of
indicator organisms.
Each species has a variety of physiological states some of which can be measured e.g.
normal and bleached corals, diseased or undiseased fish, live-dead coral cover ratio andpartial mortality of colonies. Bioindicators at the organismal and biochemical levels(biomarkers) are now commonly used around the world to assist in the process ofmonitoring change in the environment. It may be useful for Hawaii to test out theusefulness of some of these physiological indicators as part of the overall monitoring
program.
When the Reef Check program was designed, the criteria for choosing indicators
species were: ease of identification, high-value organism, and a high information
content with respect to human impacts.
What variables can be monitored most efficiently in terms of useful information
content per unit of monitoring effort?
Unfortunately, the origins of scientific monitoring of reefs lie in traditional community
ecology that was aimed at understanding relationships among different species. A
number of these methods have survived until today and are best avoided as an
unnecessary waste of effort. For example, many monitoring programs have included
coral growth forms as one parameter to be measured. Coral growth forms are a very
useful descriptive feature of reefs. And yet it is difficult to imagine when a management
decision would be taken based on a change in percentage cover of coral growth forms.
If no management decision can be made based on a shift in growth forms, there is no
point in recording this data. Many monitoring programs differentiate between
zoanthids, soft corals and sea anemones. If shifts among these three categories will not
result in a management action, then there is no reason to differentiate them in themonitoring program.
Given the limited time, staff and money available for monitoring, it is essential toformally consider which parameters provide value for money. Just as fisheries scientists
may calculate catch-per-unit-effort (CPUE), so it is possible to record information
content-per-unit-effort (ICPUE). From this perspective, lobster have a high ICPUE
because they are a highly sought after, valuable marine species. Their absence from anarea previously known for lobster may indicate high lobster fishing pressure. The
standard Reef Check core methods have been adapted for Hawaii by the inclusion of
local high-value species. Additional species could be added for increased information.
What quantitative and null hypotheses will be useful to test statistically?
It is useful to consider hypotheses for what we expect the natural range of variation to
be on reefs. This can be the basis for the Action Plan that guides management. Only
with long-term monitoring will it be possible to determine the natural range ofvariation of each parameter.
What sampling design (temporal and spatial) including controls will be used?
What statistical procedures will be used to test the hypotheses?

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It is important to consider the sampling design needs with respect to detecting change,
particularly if the sampling design is meant to produce results that are to be assessedusing parametric statistics such as ANOVA. Multiple control stations are required, andsufficient replication is needed across all levels of the sampling design. If the goal is todetect change at a particular reef, then replicates within that reef will be needed. A
nested or hierarchical design is a useful solution (Oxley, 1997). The same concernswith space are applicable to time. If an annual comparison is required, then temporalreplication is required at a smaller time interval to reveal any sub-annual variation.
Random, stratified sampling is usually most appropriate for coral reefs due to clear
zonation patterns.
What level of change is ecologically significant?
It is quite possible for a change to be statistically significant without being ecologicallysignificant. This can occur when there is a relatively small but uniform increase at manysites in a large sample. The change may be a seasonal change or due to some othernatural factor that is not something that a manager should be concerned about. On theother hand, changes may occur that are clearly ecologically significant, but due to thesampling design, can not be shown to be statistically significant. Therefore it isimportant to not only plan to rely on a statistical interpretation of change but also todecide in advance what levels of changes would be considered ecologicallysignificant in Hawaii. For example, what decrease in the live:dead coral ratio, or whatincrease in partial coral mortality or decrease in a fish populations should beconsidered sufficient cause for alarm By formally going through this decision-making
process about what changes are considered important, before changes occur, adecision matrix can be developed that gives managers a clear idea of their
responsibilities.
How will the cause of a significant change be determined?
Although strictly speaking not part of the monitoring plan, but rather the Action Plan,
it is clearly important to have a mechanism in place to try to determine the cause of astatistically and/or ecologically important change in the reef. The procedures may
include an increased frequency or number of locations for monitoring, the alerting of ateam of specialists (rapid response team) to investigate, and a listing of the methods
that could be employed. Unless such a system is planned well in advance, a majorchange could occur and be finished long before a response could be assembled.
What options are there for management action in response to a change, andwhat level of reef change should trigger a change in management?
As part of the Action Plan, once a change has been detected at a reef, and a cause has
been determined, it is useful to have a prepared plan listing possible options for
management decisions. For example, if a decrease in certain fish species is detected,
one response might be to close the area to fishing. If partial mortality of corals has
increased at a popular dive site for tourists, and it is suspected that tourists are partiallyto blame, then restrictions could be placed on the number of tourists visiting each day.

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There are many types of changes that could be traced to “natural variation.” It is
important not to invoke an inappropriate and possibly expensive management action in
response to a natural change. Therefore, it is critically important to avoid locking themanager into a particular management action in response to a given change. That is,
the Action Plan should be designed as a menu of possible actions that allow the
manager the flexibility to make a management decision based on all available evidence.
What quality assurance procedures are needed to ensure that the data arecorrect?
Quality assurance and control are now standard procedures in most commercial
enterprise. A practical QA/QC system should be designed that meets the needs of the
program without drowning staff in procedures and forms. The QA/QC system should
be formalized in the form of a QA/QC manual. The fundamental objective of thesystem should be to enable the project manager to minimize errors and to track themwhen they occur, so that they can be corrected.
What are the deficiencies of the design and how will they be dealt with?
There is no such thing as a perfect monitoring program and it is useful to review the
program and identify deficiencies on an annual basis so that contingency plans can bemade to fill gaps. The monitoring program should be sufficiently flexible to allow it tobe altered as needed in the future to take into account any new information or needs.
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English, S. C. Wilkinson and V. Baker 1997 Survey Manual for Tropical Marine
Resources. Australian Institute of Marine Science, Townsville, Australia
Carpenter, R.A. and J.E. Maragos 1989 How to Assess Environmental Impacts on
Tropical Islands and Coastal Areas. Environment and Policy Institute, East-WestCenter, Honolulu, Hawaii, USA.
Green, R.H. 1979 Sampling Design and Statistical Methods for Environmental
Biologists. Wiley, New York, USA.
Hodgson, G. (submitted) A global coral reef assessment.
Kenchington, R. and C.K. Looi. 1994. Reseaarch and Monitoring for Marine Protected
Areas. Module 8 p. 427-439 In: Staff Training Materials for the Management ofMarine Protected Areas. RCU/EAS Technical Reports Series No. 4. United Nations
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Bankok, Thailand.
McManus, JW, MCA Ablan, SG Vergara, BM Vallejo, LAB Menez, KPK Reyes,
MLG Gorospe, and L Hlamarick. 1997. ReefBase Aquanaut Survey Manual.
International Center for Living Aquatic Resources Management, Manila, Philippines.

9Oliver, J. G. De’Ath, T. Done, D. Williams, M. Furnas and P. Moran 1995 Long-TermMonitoring of the Great Barrier Reef. Status Report: Number 1 1995. AustralianInstitute of Marine Science. Townsville, Australia.
Oxley, W.G. 1997 Sampling and Monitoring Design pp. 307-320 In: English, S. C.
Wilkinson and V. Baker 1997 Survey Manual for Tropical Marine Resources.
Australian Institute of Marine Science, Townsville, Australia
Rogers, C. 1993. Coral Reef Monitoring Manual for the Caribbean and Western
Atlantic. National Park Service, Virgin Islands National Park, St. John, US Virgin
Islands.
Underwood, AJ 1993 The mechanics of spatially replicated sampling programmes todetect environmental impacts in a variable world. Australian Journal Of Ecology 18:
99-116.
Clarke KR and RM Warwick 1997 Change in Marine Communities: An Approach to
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