[Coral-List] Reliable coral reef stats
davefisk at gmail.com
Wed Sep 18 13:11:28 EDT 2013
Some time ago a question was asked on Coral List regarding the
appropriateness of Reef Check (RC) for monitoring and I seem to remember
that no real answer to the question was offered by anybody at the time. So
this latest contribution from RC headquarters has offered a chance for me
to give my two cents worth that I should have done the first time. What I
would like to know is whether there is anybody else out there in Coral-List
land who like myself, feels a little uncomfortable whenever we are given
the hard sell from Reef Check, particularly in its effort to legitimise its
scientific credential claims with what is and will always be, a simple
community awareness raising tool. Reef Check was developed solely as a
community awareness tool and has been included in the GCRMN list of
protocols under that category, and is widely understood to be the least
scientifically robust method for most ecological questions. And yet over
the years the assertion of its scientific rigour and global usefulness to
answer scientific question has grown beyond its initial purpose.
RC's main usefulness lies in getting many observers in the water over a
wide geographical scale, with the possibility of ocean wide or regional
scale phenomenon being recorded, like regional bleaching events which at
that scale, does not actually need scientific rigour to be confident that a
broad scale disturbance event is occurring.
My greatest concern is that the Reef Check juggernaut, principally because
of its well organised format, gets presented to many developing countries
as the basic tool for all reef related issues that a country may be
concerned about. This results in the collection of data that are entirely
useless for the real local issues that they may be faced with. The
monitoring data may be of some use for regional assessments but I remain
sceptical and uneasy about the extremely limited resources of these poor
countries being used for the good of regional/global assessments only. The
reason I say this is that the pro forma list of indicators species and
sample sizes and replicates required by RC are rarely useful for smaller
scale questions like Pacific Island fisheries departments (for example).
Yet many such organisations are led to believe that Reef Check is all they
need to monitor their fisheries or to answer specific disturbance issues,
or provide an accurate reef status, which it clearly cannot do.
Furthermore, the interpretation of data from a protocol like RC should be
treated with caution for a very wide range of reef organisms listed as
health indicators by RC. A good example is the use of humpheaded parrot
fish and maori wrass as 'health indicators' in the Pacific. Both species
have very large home ranges that probably extend to a kilometer or more of
reef tract, so when very small belt transects are used (RC suggests 20m x
5m belt transect replicates), any observation can only be interpreted as
the species being being present, and nothing can be said about their true
abundance or density as the sampling is inappropriate with respect to the
target species' normal home range. Most importantly, the absence of such
species in RC survey records does not mean they are not present, just that
the sampling regime is inadequate and did not cover the likelihood of them
Another significant issue is the choice of sites for RC as to their
'representativeness' with respect to the aims of a project. RC
predominantly utilises volunteers and diver/resort type people to establish
monitoring sites and to gather data, but from my experience, the choice of
sites are highly biased towards habitats and sites that are appealing to
such volunteers such as high coral cover sites, drop offs, or sites where
tourism operators can safely moor boats.
In summary, drawing conclusions on the 'health' of large regional reef
systems and the management of coastal fisheries using RC data is obviously
wrong for any inappropriately sampled species groups and in most cases the
RC protocol does not address the real issues of many countries.
Don't get me wrong, I believe there is a use for RC but I think it is not
in the areas that are becoming too frequently claimed by RC.
Now, where is my crash helmet - I suspect I may need it. Cheers Dave Fisk
> Since 1997, Reef Check has carried out a global monitoring program of
> reefs using a standardized method based on about 30 indicators including
> living coral and recently killed coral, bleached and diseased coral. Prior
> to 2005, Reef Check teams were trained and led by Masters or PhD level
> scientists who were responsible for field level Q & A. Since 2005, all
> Check data has been collected by individuals who have been through a
> training program, tested and certified to collect data. In fact about 75%
> of the data has always been collected by research scientists because Reef
> Check methods have been adopted by many countries and research institutes
> part of their core monitoring program. Independent researchers such as
> Bruno et al., have used the database for local and regional meta analyses.
> The database is available to any researcher. Our WRAS online coral reef
> database has been taken offline to transition it from a GIS to a Google
> Earth platform, and to merge it with our California NED online rocky reef
> database. http://ned.reefcheck.org/ An analysis of the 15-year coral reef
> dataset is due out in 2014. For a list of peer reviewed and other
> publications based on or related to Reef Check data please see:
> Reef Check offers regular training programs throughout the world using our
> local coordinators. If you think it is important to track coral reefs
> the next 20 years of global warming, please contact rcinfo at reefcheck.orgto
> arrange a training or if you would like to help coordinate surveys in a
> country where we do not have a coordinator.
> I am noticing two problems when researchers try to compare baselines now
> with pre-1980s data:
> 1. there is a shifting baseline in new cohorts of coral reef researchers
> have a hard time understanding what reefs actually were like 40 years ago,
> but typically have not read the old descriptive literature from pre-1970s
> such as Saville-Kent that provide exceedingly detailed descriptions of
> the shallow reefs were like; 2. a problem with meta-analyses that do not
> take into account the fact that in 2013, there are no "zero coral cover"
> data from former reefs or zones of reefs that are no longer reefs because
> they experienced 100% die off and so researchers no longer monitor them.
> Some former reef zones that were populated by Acropora palmata can still
> seen, as the dead skeletons are still in place, but those formerly
> by the more fragile A.
> cervicornis are often simply gone. This means that the current regional
> global coral cover estimates are probably underestimating the decline as
> researchers no longer include reefs that died and have not recovered.
> Gregor Hodgson, PhD
> Executive Director
> Reef Check Foundation
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