[Coral-List] Coral reef restoration -Seychelles

Captain Ahab kevin.s.moses at gmail.com
Fri Oct 16 01:13:01 EDT 2015

Hello Everyone,

Recently there have been two posts on coral reef restoration in the
Seychelles (paper 1:
http://www.tandfonline.com/doi/ref/10.2989/1814232X.2015.1078259  and paper
2: https://peerj.com/articles/1287/ ). I would like to add a few points to
what has been discussed through these two papers. I have worked as a
scientific diver at the Reef rescue project for 14 months. I have never
worked along with any of the authors , and this is one of the main reasons
I am putting my thoughts across as I feel that earlier observations and the
restoration history at cousin island, could help reef restoration managers
decide on positioning of coral nurseries and energy devoted to cleaning.

The Science in the two papers  are quite influential in the topic of
nurseries and where to place them, either at the  growing phase or just
before transplanting.  Although there were two types of nurseries created
in the reef rescuer project, net nurseries and rope nurseries, each had its
own separate purpose and intended use. I will here talk about the rope
nurseries as this formed the backbone of the study.

When Gideon levy conceived and started the project, he chose to place the
rope nurseries away from the island, Cousin island does not have a lagoon
(which of course would have been ideal) . They decided to set up their rope
nurseries about 400 m away from the shore. This has several advantages,

1)      the water was deep enough to hold mid water nurseries(i.e)  Our
transplantation site area fell within 7-10 m, hence we choose our donor
corals from about the same depth, and  this in turn determined at what
depth we  placed the nursery at  (they initially tried keeping them at  at
6m, but they were showing signs of bleaching so they were pulled down to
8m, this should also help if your growing phase coincided with a mass
bleaching event in area, you can save the fragments you are growing simply
by lowering them a few meters).

2)      Its good to have a few meters free space below your nursery
especially when you have many large rope nurseries at a time (like they
have in Seychelles) , you would not be able to visit  them all every day,
and sometimes due to nature of the sea or simply the increasing weight due
to growth  you would find the  nurseries slowly sinking to the bottom.

3)      Another reason the nursery site was far enough from shore and reef
was to have a sandy bottom, making hammering the 2m angle bar into it easy
( for anchorage).

4)       Most importantly having the nursery far enough from shore prevents
any physical damage to any surrounding natural landscape, in case ----
happens, which it once did, where we lost 3500 coral fragments due to an
out of season storm, the nursery still ended up on the other side of the
island washed up on the shore in a huge ball of tangled heavy mess two days
later.  (The damage it caused on its way to the shore was immeasurable)

5)       Cleaning was also much easier, there being safe tangle free access
from all sides to the coral filled ropes.

Moreover Cleaning is something that all nurseries would require, and all
restoration managers have to be prepared for, You will not be able to count
on nature initially for about 4- 6 weeks (the critical stage). In all our
nurseries light green turf algae were the initial colonizers, later they
were colonized by a darker redish green filamentous algae ( if it’s the
same species or not I don’t know), its only after this that other organisms
like barnacles and mussels attach to the nursery ropes/coral fragments many
weeks later. Corals for the most part are able to fight of barnacles and
over grow them. It is the competition with algae that is most critical.
Usually surgeons and parrot fishes graze on the nurseries after about 4-6
weeks of it being filled and in one place, by this time if the nurseries
are cleaned regularly (atleast once a week) the corals would have “caught
the rope” (its when coral tissue  grows over the rope through which it is
placed and fuses with itself . Once this happens cleaning can be done even
once a month, as it was only after this stage that the corals out compete
algae and coral tissue starts growing along the rope ( sorry I cant attach
pictures here on coral list, I will send it to anyone on request)

Hope some of these above factors would also help you when setting up such
large nurseries.

These are just my personal observations and opinions; you’ll will have to
enquire the thoughts of Gideon levy, Bart Linden, and Callum Roberts, the
other long term members and contributors of the team. They may or may not
agree with me. On the whole I would like to congratulate  all those I
worked under and worked with , whatever we did, we seemed to have done
right(secondary sources). The test was whether the “mass transplantation
(cementing/anchoring) of corals of various (select) branching and tabulate
species would aid in the recruitment of fishes and invertebrates, Which we
 hoped would modify the environment enough around them to allow natural
recruitment of other slower growing coral species. As the second papers
suggests, after about 10-12 thousand corals transplanted in a 100x20m space
there was the presence of fishes,  part of which was a guild of

About the initial transplanting process, We tried transplanting corals
first by directly anchoring coral filled ropes to the reef with nails, this
was not effective(pictures on the nature Seychelles reef rescuers blog),
Mostly because of the swell was strong enough to pull out the nails, and
also because of fish predation on other organisms on the rope( here using
the fish assisted cleaning may make a difference) .A small impromptu survey
about 3-4 months later found only a handful of the corals on the ropes self
attached to the substrate. After nailing in about 5000-6000 corals we
decided to cement individual corals instead.

We then added about 4500 corals by cementing, where we cut the ropes very
close to the coral tissue ( we were trying to minimize the amount of nylon
left in the sea), with this technique there was little or no dislodgment of
corals due to predation( so nature assisted cleaning was not really
needed), As the 15-20 cm of rope between corals was cut out completely
along with the barnacles and such. Only a handful of the 150-300 coral
fragments we put in every day were dislodged. This was mainly the
Pocillopora sps, as they tended to grow in a nice globular shape. The
swells just rolled them right off before the cement could harden.

It was after this point that the authors in the second paper came into the
project and conducted their experiments, What is unknown is whether they
changed their transplantation technique(including cutting of the ropes) or
if they continued the same, and since their experiment has no proper before
it is hard to say if the fish assisted cleaning was because of the 12000 or
so corals added before they conducted their experiment.

I had established a simple BACI design to understand this process of
recruitment better ( also put in two controls one healthy and one degraded
for this reason), and all efforts from the sampling to transplantation was
completely randomized(until end of April 2013). Hopefully the current crew
continued with collecting data regularly and would analyze and publish this
data soon.

Thanks for reading.


Kevin Moses.

kevin.moses at my.jcu.edu.au

kevin.s.moses at gmail.com

*I wonder, If  Bethany Hamilton had boarded the Pequod instead of Ishmael,
would Captain Ahab have met his fate at the hands of Moby Dick.*

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