[Coral-List] Subject: Re: Artificial Reefs

[David Fisk]

I think that a lack of long term reviews and monitoring of all artificial
reef (AR) projects (using a generic meaning of the term) are a key in
settling much of the differing points of view. The problem is that very few
of us really have any inclination as to how well or badly a project went
wrt the aims and reasons for undertaking a project. Dennis Hubbard's
description of his involvement in an AR is very interesting as it seems to
indicate the aims of altering water flow and wave action was successful. I
am not sure if an aim also was to create a new coral reef, as that is a
different thing all together.

Without this longer term feedback there is no way of knowing how our
efforts can be improved on what was done before or whether the whole
approach should be scrapped and something else tried. Accepting that it is
impossible to truly replicate a natural reef system, I am most concerned
when an AR is proposed as an 'ecological offset' for a development, and the
AR is then used to tip a decision in favour of a development. Typically the
end of an AR project time line is set as low as 3-5 years, which is not
enough time to really show if the 'offset' is acceptable or not. In an
absolute sense it never will be a good replacement of what was lost so it
is important that the terms of reference of such 'offsets' are greatly
improved with indicators that more closely reflect the reef that is being
compromised or destroyed by a development (eg, diversity, community
composition, relative benthos cover etc). Simply using percent coral cover
or evidence of natural recruitment as a success indicator is not adequate,
as is the short time frame for monitoring the AR. Other AR projects that
attempt to move the most vulnerable and less common coral colonies out of a
development's way is also questionable but better than doing nothing, as
from what I have heard, it is not too successful no matter how much state
of the art knowledge is applied to the issue.

So caution is definitely necessary starting with the presumption that
whatever is attempted wrt AR's, they should not be looked on as a
substitute or replacement for a naturally occurring reef.