Reef Help Guide

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REEFHELP

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Published in 2006 by:Na ture Conservati on Group (N atcog)www.natcog.org

ISBN 955-1594-00-2

Nature Conservation group 2006Al l Copyrights Reserved

Publication and project funded by:

United Nations Development ProgramGlobal Enviromental Facility / Small Grants Program

Addi ti onal as si st anceUnited Nation Volunteer Program

Photographs:Pras anna Weerak kody,Noy el Vi th anageSaji th Subh ash ana

Layout, Graphics and illustrations:Pras anna Weerakkody

Colonies of coral killed by the 1998 coral bleaching event


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An introduction toassisted restoration of

degradedcoral environments in

Sri Lanka

Nature Conservation GroupNature Conservation GroupNature Conservation GroupNature Conservation GroupNature Conservation GroupReef Keeper ProgramReef Keeper ProgramReef Keeper ProgramReef Keeper ProgramReef Keeper Program

REEF

HELPguide

Prasanna WeerakkodyPrasanna WeerakkodyPrasanna WeerakkodyPrasanna WeerakkodyPrasanna Weerakkody

Funded by

The United Nations Development ProgramGlobal Environmental Facility /

Small Grants Program


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Pdf version, Nature Conservation group 2006

CCCCCONTENTSONTENTSONTENTSONTENTSONTENTSIntroduction 5Marine Bio-diversity of Sri Lanka 1 0

What is a Coral reef 1 5Causes of Coral reef degradation 1 9

1.Use of destructive fishing methods 1 92.Overfishing and un-managed 20 selective collection

3.Removal of reef coral for lime trade 204.Un-regulated tourism 205.Collection of marine organism for souvenirs 206.Un-planned and in-appropriate coastal 2 1 development7.Boat and anchor damage 2 18.Pollution 229.Natural Disasters 23Coral Bleaching event & 1998 25

Status of Coral reefs of Sri Lanka 26Can coral reefs be restored 29

Helping the reef 30Assessing reef health 3 1Keeping a reef healthy 33Restoring coral cover 36

Assessing the physical characters of the reef 3 7Restoring coral cover through replanting 41

Handling coral 42Coral nurseries 42Replanting coral 43

Site selection 43

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Finding the right corals 44A selection of coral species usefullin reef restoration 45The Technique 54

Reef Invasive species an overview 5 7Chronology of major reef infestations 5 7 in Sri Lanka

Gallery of reef invasive species 60ANIMALSGreen Ascidian 60Black sponge 62Corallimorph 63Palythoa/zooanthids 65Crown of thorns Seastar 65Parrotfish 66Coral snails 66

Tube worms 6 7ALGAEHalimeda 6 7Ulva 68Hypnea 69Montipora sand accumulation 69CORALDISEASESPink band disease 69Gray spot disease 7 0

Afterword 7 1Acknowledgements 7 3Index 7 4

Dedication

t o

my mother;for instilling

a spirit of adventure in the persuit of knowledge;wider horizons in perception of the worldlove in great measure for even little things

anda desire to make things better

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Replanted coral on Rumassala reef

Colonies of Pocillopora damicornis and Acropora formosa onCoral nursery panels at Rumassala

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IIIIINTRODUCTIONNTRODUCTIONNTRODUCTIONNTRODUCTIONNTRODUCTION

In 1992 the Nature Conservation Group Initiated a surveyof the reef beneath the Rumassala hill. This reef secluded

by steep cliff faces and facing the Gall bay was at that timeunknown to most, and in its isolation remained one of thebest preserved coastal reefs in the Southern part of SriLanka. Some Natcog members were familier with this reefanother decade before as far back as early 1980s. Theabundance of life and the peaceful surroundings made it afavourite dive site till the early 1990s. The proposed planfor the development of a major harbour at Galle threatened

the reef with complete destruction as it was proposed tobury the reef in tons of concrete to construct a massive jettyand container facility on the site. An intensive study of thereef and its bio-diversity was undertaken in 1992-3, thefindings of the survey were pivotal in the campaign to savethe reef. Post to the initial surveys the team continued aregular monitoring program on the reef documenting the

gradual processors of change and working with thecommunity to reduce harmful impacts. In 1996 a stormcaused significant damage to the reef razing a section of thereef to rubble: The storm raged through toppling large coraltables and laid a massive strand of Staghorn coral broken,scattered and piled up in places, the reef base stripped tobare rock except for few hard attached encrusting corals.

The damage though intense was fortunately limited to asmall section of the reef. The event was quickly followed bywhat was to be the first of a series of events where previouslybenign reef organisms began population blooms and turnedinvasive. This caused significant damage to reef corals. Aspecies of Green coloured colonial Ascidian barely acentimetre across had grown over 20% of the reef surfaceswithin 2 months. The direct and indirect effects of humanactivity affecting the reef health too were on the increase.In this background the Nature Conservation Groups field

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program evolved from general surveys to an endeavor inactively managing and restoring degrading coralenvironments.

1996

In 1996 a storm raged through the Rumassala reef with 8-foot breakers approaching from the South West andpounding the Rumassala hillsides on the Northern sectionof the reef. While the Watering point headland shelteredmost of the reef, the storm surges left a wide path ofdestruction on the Northern section of the reef. A largemeadow of Staghorn coral stretching over 60 meters long

and 15 meters wide close to the reef crest was reduced intorubble as if a huge bulldozer had cut a path across it. Massivetable corals 2.5 meters across were broken, toppled andthrown several meters away. Large amounts of broken coralwas scattered through out the reef and was dying as theykept rolling and abrading over the reef and being smotheredin sand.

Initially the field teams were looking at saving as much ofthe broken coral fragments as possible and restoring thelost coral cover of the damaged sections of the reef. After ahigh rate of failure in saving coral through jamming brokencoral pieces into crevices on the reef. The team began itsinitiation into an experiment in coral cover restoration thatwas to prove a long term and important endeavor.

The 1996 storm left another longer-term legacy thatwas also to prove a greater challenge for the crew. Withintwo months post to the storm a massive population explosionof a small green colonial Ascidian was beginning to play havocwith the reef. The centimeter long colonies had spread tocover almost 20% of the reef substrates and were invasive

over corals. Settling on the base of the coral colony theascidians were budding new colonies spreading over the coralin a thick sprawling mat. The Ascidian was identified as

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belonging to the family Didemnidae and to generaDidemnum, Trididemnum orDiplosoma. The species usedshading to kill the coral by starving it as a means ofinfestation; and did not show the advancing burn markson the coral characteristic of species that use toxins in

attacking corals.

1998The year 1998 remains the most significant turning pointin the natural history of coral reefs in Sri Lanka. The El-nino; Southern oscillationrelated weather

conditions causedsignificant increase in theaverage watertemperature, whichcaused the most intensiveand widespread coralbleaching event recordedin the Indian Ocean. Thewarming of the waterscaused the corals to bleachtheir colour and becomewhite over most of theWestern, Southern andSouth-eastern reefs in SriLanka; within several

months over 50% of thelive coral area in Sri Lankawas killed; in the Southand Western shores theamount was about 80%.The 1998 bleaching eventkilled off several reefs and

caused massive damage to most others. Many coral specieswere reduced almost to extinction within the coastline and

The deadreefs afterthebleachingevent;overgrown

with algaewas soon

populatedby largeschools ofherbivo-rous fishes

Bleachedcorals atRumassalareef

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altered the structure and ecology of the reefs in profoundways.

Post to the bleaching event and the massive coral death,the Nature Conservation Group with its partners initiated a

program to study and develop ways of assisting the naturalre-colonisation of dead reef areas with coral and speedingup the process of restoring the reefs. The team had toexperiment with different techniques as there was little orno guidelines available on coral restoration, as the subjectitself being a relatively new science, globally. The teamdeveloped several techniques that can be used with good

results to reduce the mortality of corals and assist inrestoring live coral cover of reefs.

This document provides a brief background to the process;as an introduction to the new comers interested inconservation of coral reefs into the basic methods ofrestoration of shallow coral areas.

Tons ofdead coral

w a s h e d on to thebeach at

Rumassalareef post

to astorm in

year2000

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Counter clockwise from top left:

1.Replanteed coral on Nurserypanel,2.same Acropora nubins after two

years of growth.3. Coral newly recruited fromplancto ni c larvae,4. A transplanted colony of

Acropora fo rmos a coral atRumassala.5. table corals regrown 6 yearsafter the bleaching event.

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MMMMMARINEARINEARINEARINEARINE BBBBBIOIOIOIOIO-----DIVERSITYDIVERSITYDIVERSITYDIVERSITYDIVERSITY OFOFOFOFOF SSSSSRIRIRIRIRILLLLLANKAANKAANKAANKAANKA

The Island Nation of Sri Lanka,; hangs at the apex of

the great Indian continental shelf projecting deep into theopen Indian Ocean. This unique location brings in a richdiversity of life within Sri Lankan waters as animals of boththe continental shelf and the deep Oceanic waters are foundwithin Sri Lankan maritime zone.

Sri Lanka with a land area of 65,610 Km2 is surrounded

by a coastline approximately 1770km. in length containingmany marine habitats including Estuaries, Mangroves, Sandand mud flats, Sea-grass beds, Beaches, Rocky shores, Sand-stone reefs, Coral reefs and open pelagic waters. The Coun-try claims an Exclusive Economic Zone (EEZ) that extends200 km. and covers over 256,400 Km2on all sides exceptat the boundary with India. All natural resources and spe-

Mariti me zones ofSri Lanka sh owing

the territorial sea;Exc lusi ve Ec onomi c

and PollutionPreventi on zone

and the boundariesbetween India.

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cies of life found within this zone is regarded to belong to Sri

LankaSri Lanka Coastal Physical data Shoreline: 1770 km Total Area of Land: 65,610 km2

Total area of continental shelf: 30,000 km2

Total area EEZ 256,410 km2

The seas around Sri Lanka are rich in Marine life; withhabitats ranging from beaches, rocky shores, coastal man-groves, sea grass beds, sandy and muddy floors, reefs, theopen ocean and deep sea floors. The reefs itself can be fur-

Indian Sub-continent

SRI LANKA

MaldiveIslands

LakshadweepIslands

Chagos

Islands

Andman&

NicobarIslands

I n d i a n O cea n

CONTINENTAL SHELF

The locationof Sri Lankaon the South

Asian conti-nental shelfand exposedto the open

Indian Oceanon three

sides.

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ther sub divided according to the depth and the structuralmaterial as Rock / granite reefs, Beach-rock / Sandstonereefs and Coral reefs. The first two categories of reefs arecommoner and can be found from shallow to the deepestcontinental areas. The coral reefs in Sri Lanka are restricted

to fringing reefs lining the coastal shallows and shallowpeaks of offshore ridges.

Sri Lanka is situated in an ideal location that providesconditions necessary to support a higher bio-diversity dueto several special features.

Located in the Warm clear waters of the Tropics and

within the Indo-West Pacific Zoogeographic zone.

Located on the Continental shelf of the Indian sub-continent supporting shelf dwelling species and en-riched by nutrient outflow from river sediments.

Located at the tip of the Indian headland extendingdeep into the Indian ocean, Sri Lanka is enclosed on3 sides by deep ocean and allow access to oceanicspecies and currents.

Flanked by the Chagos-Maldive-Lakshadveep andAndaman- Nicobar chains of coral Islands. Sri Lankancoasts are open to planktonic species replenishmentthrough oceanic currents.

Sri Lanka is rich in marine bio-diversity, the Coral reefsare the richest of the marine ecosystems. Generally reefsor hard substrates support more life than sea grass beds,sandy or muddy sea floors. The open ocean supports a freeliving community of animals often important for fisheries.The oceanic environments are also important for the ma-

rine mammals and sea birds as well. The actual richness oflife in our seas is far from adequately assessed; as mostgroups of life had not been studied properly.

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MARINE BIO-DIVERSITY OF SRI LANKA.

Marine MammalsCetacea (Whales/Dolphins) 27 species

in 6 Families

Sirenia (Dugong) 1 species

Marine ReptilesTurtles 5 species

in 2 FamiliesSea snakes 12 speciesSalt water Crocodile 1 species

Sea Birds 49 species in 8 FamiliesPetrels & Sheerwaters 10Storm-petrels 2Tropicbirds 2Boobies 3Frigates 3Skuas 4Terns & Noddies 18Gulls 7

Corals >183 species in 68 Genera

Fishes > 1200 species within EEZ limits including> 700 species of reef fishes

Echinoderms 206 species recorded(estimated aprox. 250 species)

Mollusks 1000 +?

No proper survey has been carried out to estimate thenumber of species of Algae, Sponges, Cnidarians, Tunicates,

Worms, etc.

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Carpilius convexus

Calappa lophosCalappa philargius

Calappa calappa

Calappa hepatica

Calappa gallus

Trapezia cymodoce

Trapezia rufopunctata

Trapezia reticulata

Carpilius maculatus

Demania raynaudii

Atergatis interrigimus

Coenobita rugosa

Dardanus logopodes

Dardnus guttatus

Some Coastal Crabs andHermit Crabs of Sri Lanka

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WWWWWHATHATHATHATHAT ISISISISIS AAAAA CCCCCORALORALORALORALORAL REEFREEFREEFREEFREEF

A forest is a collection of organisms from trees to mush-rooms, beetles to birds and larger mammals. When all its

parts are together the forest is an eco-system or a systemof life. Though many animals and plants contribute to mak-ing a forest a forest, the primary organism responsible forthe structure of a forest is the tree. Like wise a Coral reef isan underwater eco-system comprising of thousands of lifeforms, but like the tree in a forest the coral reef is built bycolonies of tiny reef animals known as Coral

polyps.

The coral polyp belongs to the Animal phylum Cnidaria(Coelenterata) and its sub class Anthozoa. Individually coralpolyps are small and rarely grow bigger than a centimetreacross; the coral animals usually live in colonies and eachpolyp build a limestone skeleton which links with the skel-etons of all other members of the colony over generationsto form the structures we readily recognise as a coral.

The basic shape of a coral animal consist of a sac likebody with a single ended food channel that open in a centralmouth; which is surrounded with tentacles that catch pray,clean itself and also provide a surface for photo-syntheticalgae. The coral animal unlike most of its relatives secretes

a limestone cup at its base that provides support and pro-tects the coral polyp. Aggregation of these limestone cupsbuilt by generation upon generation of corals grows in tothe large and widely variegated structures we commonlyrefer to as corals. Colonies of thousands of tiny coral polypsbuild coral colonies. And aggregations of thousands of coralcolonies of many different species form coral reefs.

Though there are coral species found from the polarseas to the deepest oceans it is only in the shallow tropical

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seas that the coral animal can form the massive structuresof a coral reef. To be able to do this feat the coral animalforms an association with a single celled algae that wouldlive within the tissue of the coral animal feeding off on thecarbon dioxide produced by the coral polyp; in turn the

oxygen and nutrients produced by the algae is transferredto the coral providing most of its nutrient and metabolicneeds; giving the coral the edge needed to use its energiesinto growing and reproducing itself to a coral reef. The colourof a coral is also due to the algal tenets living within thecoral tissue.

This symbiotic arrangement is not without its draw-backs; relying on the presence of the algae the coral alsoinherits the limitations of its partner. As the algae dependon well lit warm shallow seas, the corals are also restrictedto build reefs within the same sea conditions and with stablehigh salinities.

The corals come in many species. These colonies cantake many shapes. The basic forms are classified as Branch-ing (Staghorns, Elk-horns), Fingerlike (digitate), Plates andtables(tabulate), leaflike (foliaceus), dome like(massive),semi domelike (sub-massive), Encrusting and free living.

Crosssection of

a coralpolyp

Limestone

skeleton

Central mouth leadsinto a simple one

ended gut

A ring of tentaclesaround the mouth

carry stinging cellsthat catch small

animals and bringthem to the mouth

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Though most corals can be identified into the family it be-longs to by looking at the coral colony it is often needed tolook closely at the shape of each coral animal to identify cor-als at a more refined level. Each coral polyp is referred to as

a corallite and the structure of the corallites is used to grouppolyps on the surface of the coral colony into Plocoid(corallites with own walls), Phaceloid (also with own wallsbut corallites longer and tubular), Cerioid (polyps sharewalls), Meandroid (brain corals-polyps form valleys),flabello-meandroid (valleys without common walls) andmushroom (solitary, free-living) patterns.

Corals need special conditions to build reefs; and formreefs only in the warm coastal waters between the tropicsof Cancer and Capricorn. requiring well lit shallow seas anda hard substrate to grow on and do not proliferate in turbidareas and where the substrate is unstable.

The Tropical coral reef ecosystems are divided into sev-eral Zoo-geographic regions where each would contain dis-tinct assemblages of species unique to each. These areformed by natural boundaries barring the intermixing of

Massive

Sub-massive

Digitate

Encrusti ng

Branching

Fo liaceus

Tabulate

Basicgrowth

formcategoriesof coral

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species between different regions that cause isolation overmillennia, resulting in species to evolve independently ofthe others. In the Ocean; the boundaries could be physicalas landmasses or climatic as polar waters separating theregions.

Main zoo-geographic regions of the seas Indo-West Pacific East Pacific West Atlantic East AtlanticThe Indo-West Pacific region supports the highest

marine Bio-diversity in the world and is recognized as the

cradle of coral reefs.

The reefs serve many purposes in the coastline; theyare important centers of bio-diversity, fisheries productionand nursery grounds, aesthetics, tourism, coastal stabiliza-tion and barriers against coastal erosion.

Most coral reefs are located near the shore where theyare easily accessible; they are often subject to the brunt ofpollution, human impacts and extreme weather events.Coral reefs in Sri Lanka are under threat and are continu-ally being degraded by both human and natural causes.

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CCCCCAUSESAUSESAUSESAUSESAUSES OFOFOFOFOFCCCCCORALORALORALORALORAL REEFREEFREEFREEFREEF DDDDDEGRADATIONEGRADATIONEGRADATIONEGRADATIONEGRADATION

The Survival of Coral reefs have come under threat

from human activities as more and more coastal areas aredeveloped and more resources are extracted from the sea.The coral reefs on the Southern to Western shores of SriLanka have taken the impact of it. The threats to coral reefscan be broadly categorized under physical damage, pollu-tion, extraction and natural causes.

The threats to the reefs were prioritized at differenttimes based on our understanding and involvement with thereefs and the most significant causes identifiable at eachperiod. In the 70s and yearly 80s Coral mining was con-sidered the biggest reef related issue as the then non-div-ing management community could not see the effects downbelow and could only focus on the coral lime being brought

ashore. Post to the setting up of the Coral Reef ResearchUnit at NARA the list got diversified into Bad fishery prac-tices (both ornamental and food), tourism, and a host of otherissues. During the mid 1990s the trend was changing againthis time from direct effects of man to far more destructivenatural events.

Some of the major causes of coral reef destruction isdiscussed below.

1. USE OF DESTRUCTIVE FISHING METHODSPhysical damage is caused to the coral structure of the

reef from many fishery related activities. These include theuse of explosives (dynamite fishing), entanglement of bot-tom set nets and the moxy a net used by the ornamental

fish collectors. The ornamental fish collectors cause addi-tional and usually avoidable damage as they break up andover turn coral boulders to collect fish and invertebrates

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hidden below or within them. The lost pieces of syntheticfishing nets cause degradation of corals by binding onto cor-als and rubbing on them, referred to as ghost nets they alsocontinue to trap marine organisms.

2. OVER FISHING AND UNMANAGEDSELECTIVE COLLECTION

The ornamental aquarium fishery, shellfish and ho-lothurians export trade and spear fishing have had an im-pact on the reef communities in selectively removing spe-cies and individuals of specific size categories. (Extractionof breeders, new recruits etc.) This could lead to alteration

of the balance of the ecosystem as key trophic / commu-nity elements are affected.

3. REMOVAL OF REEF CORAL FOR THE LIMETRADE.

Coral mining for lime is carried out on some reef areassuch as Akurala and Rekawa and constitutes a serious butlocalized threat to coral reefs, as the basic reef structure islost the chances of re-colonization of the reef is also lost.

4. UN-REGULATED TOURISM.Tourism impact on the reefs when the number of visi-

tors to an area exceeds the carrying capacity of the reef toabsorb incidental damage by visitors; such as walking,touching and striking coral with swim fins etc. The coastal

developers/hoteliers infringe on the coastal dynamics bybuilding close to or on marine areas, and release sewageand refuse into the waters close to the coral reef. Extrac-tion of coral and other shellfish etc. for the souvenir tradealso contribute to the tourism impact on the reefs.

5. COLLECTION OF MARINE ORGANISMS

FOR SOUVENIRS.The collection of coral, Shells and other reef organisms

has become a significant threat to reefs in some areas.

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Though the act of picking up a dead shell on a beach doesnot cause significant harm, commercial collection of souve-nirs for sale and excessive collection by groups on localizedsites (eg. At school field trips) can lead to harmful levels ofextraction if not controlled.

6. UNPLANNED AND INAPPROPRIATECOASTAL DEVELOPMENT

Development of harbors, revetments, Groins, sea wallsand other coastal structures impact the coral reefs directlyby building over coral areas and through changes to thecoastal sand transport by increasing sedimentation and ac-

cretion within coral reefs.

Some planned major development schemes in the Southcoast such as the proposed Galle harbor development en-visaged to build over a rich coral reef leading to extermi-nation of the reef.

The construction of a breakwater at the fishery harborin Hikkaduwa is believed to be the cause for sand filling ofboth the Hikkaduwa Marine Sanctuary and the Akurala reef.

The warmed water plumes released by coastal powerplants (eg. Proposed Norochchole, and the Trincomale coalthermal plants.) could damage coral reefs in the area as thesea water temperature would be elevated by several de-

grees over a long period of time, which could trigger localbleaching events and reef death.

7. BOAT AND ANCHOR DAMAGEUse of coral reef lagoons as anchorages for small and

medium sized boats has affected reefs as the heavy anchorsand dragging anchor chains break, abrade and over-turn

coral colonies (e.g. Hikkaduwa, Kapparathota) . The fishingcraft anchorages further affected the reef as fish off-load-ing and cleaning operations also contribute to pollution of

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the surrounding areas. Unauthorized channel blasting overthe reef flat/crest by fishermen to open access channels forthe boats also destroy reef sections. Glass bottom boatsdamage the reef as the boats are regularly rammed on tothe reef to provide better viewing opportunities for the visi-

tors.

8. POLLUTION(COASTAL, SEWAGE, SEDIMENTATION, RIVERRUNOFF, PETROCHEMICALS, ETC.)

The degradation of the coastal marine environment issteadily increasing as rivers and canals carry heavier loads

of untreated domestic sewage , industrial pollution and sedi-ment into the coastal seas. The development of the coastalbelt and tourism has also contributed to the addition of nonbio-degradable plastics and other solid waste into the wa-ters. Waste from tourist hotels on the coastline, petrochemi-cals from boats, bilge water pumping and tank cleaning by

strand ofbleached

Acorporaformosa

corals.this

speciesw a s

almost extermi-

nated onthe Southcoast by

thisevent.

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tanker ships and spills. fishery spoils, coastal industry andsedimentation from river run off cause serious adverse im-pacts on the reef. This may also contribute significantly indisrupting the ecological balance of the reef and may be caus-ative in increasing coral diseases and triggering attacks by

invasive reef organisms.

9. NATURAL DISASTERSThe effects of natural processors and climatic events

are becoming a growing threat to coral reefs as the inten-sity and frequency of such events are steadily on the in-crease. Currently they are overtaking in importance as the

major factor in reef destruction over the normal humancauses.

SAND FILLINGThough coral reefs are a primary agent in acting as a

wave barrier in stabilizing eroding shorelines. They are atthe mercy of sand filling (accretion) events. The 1997 beachaccretion event at Akurala smothered and completely bur-

ied the shallow Akurala coral reef under several feet of sandwithin a time span of about one month. The HikkaduwaMarine Park is also gradually filling up and is at risk of dis-appearing under the sand if no remedial action is taken.

GLOBALWARMING/ CORAL BLEACHINGThe changing global climate triggers periodic events

which causes warming of the marine environments. Theseare known to trigger coral bleaching events often resultingin high coral mortality. The coral bleaching in 1998 wasthe severest such event reported in Sri Lankan waters kill-ing off 70-80% of coral reefs in the Southern coasts and anestimated 50% of Sri Lankan corals.

STORMSStorms and associated wave surges are known to dam-

age reefs periodically, often these affect the shallower moreexposed sections of reefs. Storms damage coral reefs as

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the wave force causes coral breakage, move coral debrisand sand on reefs. They can also cause significant re-mod-eling of reef environments; changing the current patterns.The incidence and intensity of Storms are on the increasewith the changes to global climate. On the positive side

storms of moderate intensity can help in clearing surfacedebris from a reef and leaving reef surfaces cleaner andavailable for new coral settlement.

TSUNAMIThe 26thDecember 2004 Tsunami is the only properly

identified Tidal wave on record in Sri Lanka. The damage

to submarine environments from Tidal waves differs fromstorms in its mechanics. The location, geography both coastaland under water affect the way the reefs are impacted. Dur-ing the 2004 Tsunami the reefs in the direct path of thetidal wave; especially in the east coast seem to have suf-fered heavier physical damage, while the Southern andWestern reefs received less direct damage as the wave ap-

proached the coast more as an accelerated tide. Indirectdamage may be caused by erosion from the strong currentscreated by the receding tidal waters and through the largemasses of debris washed off from land areas and being de-posited on the reefs causing abrasion and smothering.

INFESTATIONS /REEF INVASIVE SPECIES

Due to yet unidentified reasons, sudden increse in thepopulation of normally insignificant reef organisms spreadfast over the reef surfaces at an accelerated speed killing offlive coral cover in competition for reef space. The speciesinclude both algae and faunal groups ranging from simplesponges to the Crown of thorns sea-star. The reason or trig-gers for these population bursts are unexplained and maybe the result of reduction of predatory species or creation of

conditions that favor increased survival of larvae of inva-sive species.

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CCCCCORALORALORALORALORAL BLEACHINGBLEACHINGBLEACHINGBLEACHINGBLEACHING EVENTSEVENTSEVENTSEVENTSEVENTS.& 1998.& 1998.& 1998.& 1998.& 1998

The phenomenon of Coral bleaching is caused by corals subjected to severe environmental

or pathological stress evicting or losing the symbiotic algae that reside within their

tissues providing most of the food, metabolic needs and pigmentation of the corals.

High water temperature and increased UV radiation is known as major trigger factors incausing such events. The corals take on a stark white or very pale color as the

pigmentation is lost; and in this state corals are referred to as being Bleached. The

condition can be reversed if the environmental conditions return to normal within a

short span of time allowing the coral tissue to be re-colonized by algae. If the bleaching

is extensive it could lead to starvation of the coral animal leading to weakening and die

off of coral colonies. But the level of recovery/ coral mortality is dependent on the

severity, duration, and other environmental stressors that may add to the event.

The year 1998 observed the most severe coral bleaching observed in Sri Lanka in

documented times. The event was followed by the death of corals at a scale unprecedented

in known history of Sri Lanka.

During March of 1998 an unusually warm mass of seawater was reported to be forming

close to East Madagascar and Seychelles Islands in the South Western Indian Ocean.

The warm water soon formed a current that kept on spreading Northwards through

Seychelles Islands, Maldives and across Sri Lanka to South India and extending up to

Lakshadweep islands and even up to Andaman and Nicobar Islands. The warm waterplume affected some parts of the central Indo-pacific region around Thailand and

Philippines as well. It is believed that this warm water plume was the result of a long and

complex series of climatic and ocean-processors that had its inception linked to the

famed El-Nio Southern Oscillation climatic event in Eastern Atlantic Ocean.

By mid April all shallow water reefs in the South and Western coasts of Sri Lanka was

affected with almost all coral being bleached; the once colorful reefs had taken a stark

white color as the sea water had become hot. The water temperature at the peak of the

event reached temperatures of 36oCelsius. By mid May water conditions were beginningto normalize but some corals remained in a partially bleached even at the beginning of

November.

The sensitivity of corals to the heat varied withMontipora aequituberculatabeing the

most resistant, most colonies of this species did not bleach even at the peak of the

event. Colonies of Porites rus,Montipora,Leptoria, Favids, and some Pocilopora species

were among the first species to recover. Almost all Staghorn coralAcropora formosa,

Fire coral Millipora was killed and suffered near extinction on the coastline. The live

coral cover of coastal reefs in Southern Sri Lanka was reduced by 80%. Sri Lanka is

estimated to have lost about half its live coral cover within this event with most of the

surviving reefs located in the East coast of Sri Lanka.

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SSSSSTATUSTATUSTATUSTATUSTATUS OFOFOFOFOF CCCCCORALORALORALORALORAL REEFSREEFSREEFSREEFSREEFS OFOFOFOFOFSSSSSRIRIRIRIRI LLLLLANKAANKAANKAANKAANKA.....

The coastline of Sri Lanka contain many fringing coralreefs. Prior to 1998 coral reefs were recorded from Akurala,Hikkaduwa, Galle, Rumassala, Unawatuna, Mihiripanne,Habaraduwa, Kabalana, Kapparathota, Polhena, Mirissa,Tangalle, Rekawa, Ussangoda to the Basses on the Southwest and Southern shores to Pothwil, Thirukowil,Kalmune,

Kalkuda, Pasikuda, Trincomalee, Nilaweli and Kutchaweliin the East coast, Kandakuliya, Talawila, KalpitiyaSilawathurai in the North west and around many Islands inthe North. The live coral cover on most major coral reefsaveraged around 70-80% of its surface cover, most reefscontained a high diversity of reef fauna. Over 530 speciesof Reef fish was recorded from surveys at Rumassala reefbetween 1992 and 1995. The diversity of the reef fish fam-

A deadreef in

unaw atunakilled by

the 1998b l e a c h i n g

e v e n t

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ily Chaetodontidae (Butterflyfishes) is taken as an indica-tor of the richness of a reef. 39 species of Butterflyfish spe-cies were recorded from Sri Lankan reefs with major reefsregularly containing about 20-25 species of Butterflyfishes.

The sequence of climatic events during the last decadechanged the fate of Sri Lankan coral reefs dramatically. Theemergence of several severe storms, increasing infestationsof invasive reef species, and most importantly the Coralbleaching event of 1998 caused the loss of about half or moreof Sri Lankan coral reefs. The 1998 event alone is estimatedto have reduced the coral cover in the south west coast down

by about 70-80%. Many reefs were killed outright, few oncegrand reefs barely survived and the structure and speciescomposition of surviving reefs were changed drastically.Many of the previous dominant species on the reefs haddisappeared; the storms had rearranged coral structuresand removed tones of dead coral from the reefs. Reef habi-tats were dissapearing and reef fauna was changing in ad-aptation to the new situation. While all this was going onnaturally the loss of fisheries was forcing local fisher folk toadopt harsher fishing methods to extract a living off whatever resources that remained. The 2004 Tsunami causedmore direct damage to the east coast reefs that survivedthe 1998 bleaching event. Pollution, and other human causeswas also on the increase adding to the burden.

The reefs though badly degraded and still under pres-sure; are still struggling to survive and do grow back slowly.If the current trends continue it is very doubtful if SriLankan coral reefs would survive another decade of bat-tering.

It is no longer sufficient to conserve coral reefs;

it is time to go one step further and Restore the lostreefs back.

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A reef rebuilt using dead coral boulders to create a new reef basewith replanted live croal; after one year of growth.

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CCCCCANANANANAN CCCCCORALORALORALORALORAL RRRRREEFSEEFSEEFSEEFSEEFS BEBEBEBEBERRRRRESTOREDESTOREDESTOREDESTOREDESTORED?????

As the trees build the matrix within which the com-

plex web of life that is a forest is created. The living coralsform the structure of a coral reef. As the forest is also lostwhen the trees are gone; when the corals are dead the reefsdegrade and crumble away.

If the forest is destroyed no one can expect to physi-cally restore the forest in its entirety, but by restoring the

tree cover and structure the return of the forest could beaccelerated. In the restoration of degraded forests the prac-tices of re-planting trees as a means of habitat enrichmenthas been practiced for long and has well established guide-

lines. Any approach to coral reef restoration is firstly facedby the problem that no such guidelines exist. Coral reef res-toration is a new science/art. Those who endeavor having

to find suitable techniques mostly by trial and error. Butthis is not to say that such things could not be achieved.Though much work remains tobe done.

Replanti ngcoral

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The coral reefs around the world keep slipping away;and mere conservation practices seem inadequate to keeppace with the loss. While Scientists around the world con-tinue to debate the pros and cons of the many newly emerg-ing restoration techniques; the need for restoration is be-

coming a priority in preserving coral ecosystems for the fu-ture.

It is difficult to focus on preserving the large number ofspecies that form these ecosystems individually. Conserv-ing a habitat and restoring environments lead to a cascadeof benefits that will eventually lead to the conservation of

all the species that make up the reef.

HELPING THE REEF

Coral reefs need all the help they could get to survive.And it is not difficult for a concerned diver to contribute tothe improvement of a reef and help coral survive just a littlebetter. The first thing is to be responsible and sensitive tothe reef. Being a good diver and avoiding unnecessary physi-cal contact with coral reduces the stress you impose on thereef just by diving. Mind where your fins hit, be carefulwhere you grab on to rocks, dont kick up so much sand andsilt and dont stand and walk over coral. If you need to domore you could help by collecting and removing junk and

debris from the reef. This will help the corals survive andmake the reef look better for you and others; and will go along way to keep a reef healthy. And if you are dead seriousyou could get involved in restoring corals.

This is easier said than done, restoring a reef should becarried out only with a good knowledge and understanding

of what you are doing; or you would end up doing far moredamage by your mistakes. This guide is not meant to be amanual for reef restoration but an introduction and a refer-

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ence source. It is important to seek training to gain a strongknowledge base if you aim at initiating serious restorationwork.

ASSESSING REEF HEALTH

The first step in restoration is finding out if there is aneed for it on any reef. If so a preliminary survey should becarried out to assess the status of a reef before any activityis undertaken.

It is important to be able to check and record the healthand condition of a reef over time. To do this one need toidentify the criteria used in assessing reef condition and beable to interpret them. One of the most important indica-tors is the composition of the sea floor (substrate) of thereef and check how much of it is covered by living coral andhow much coral has died recently, in addition it is also im-portant to identify the trends in changes of other organ-isms occurring and competing with coral on a reef. Thereare many ways in which this can be measured but one ofthe easiest and practical methods is the point transect (asystem now widely used by the REEF CHECK /Global CoralReef Monitoring Network (GCRMN) etc.)*

THE POINT TRANSECTThis system uses a 20m tape with markings at each

meter; laid randomly over a reef area. A diver would thenfollow the transect and make notes on the organisms thatwould lie directly beneath the marked points under the tapeaccording to identified categories. At the end of each transect40 points of data are collected and the transect is repeatedat a different location within the reef. For most purposes at

least 3 transects must be carried out to sample a reef ad-equately. You need to carry out as many transects as ispossibe to get better accuracy of the data . Once all the data

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is collected the points under each category is totaled, aver-aged and compared to give the percentage of points relatedto the total number of data points collected. The percent-age of ground occupied by each type of organisms and ma-terial composing the reef floor can be calculated this way

easily.

The categories used could be modified according to thesite and the way a team would work. It is always good tocollect more information than immediately needed whilecarrying out the transect (species involved etc.) and use thebroader categories in assessment as there is no way of get-

ting additional information for later use if it is not collectedat the time of doing the transect. A general list of catego-ries that are important is found on page 34.

Additional categories can be created depending on spe-cific organisms or requirements that you need to monitorfor management of your site.

Live coral (LC) will give you the amount of living coralpresent on the reef as a percentage. Dead coral (DC) indi-cates corals that had died recently, Dead coral would aftersome time transform in to inert substrates on which otheranimals would settle where they would be classified alongwith Rocks in general (RK), more fragile types of coral wouldbreak up and fall to the sea floor after some time when dead

and are referred to as Coral rubble (CR), Differentiatingbetween sand (SA) and silt (SI) is important as silt if stirredup could pose a threat to corals by smothering them. Thepresence of any other organism that occurs in significantquantities on the reef should be taken in to account and re-corded to assess their impact on the reef (other organisms)

A reef that contains a higher amount of live coral (LC)is in a better state than a reef with less live coral, A reef

*The system has been modified to suit local conditions.

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where the larger amounts of recent dead coral (DC) is re-corded is in danger; as the reef is dying due to some cause.

Monitoring the trends in Invasive reef species and otherparameters may give clues to what is causing the coral death.Some times a lowering of the live coral cover may not resultin an increase in dead coral if it is caused by an invasivespecies; in which case the lost coral area will be occupied bythat organism. Storms can break coral and pulverize themin to rubble directly and cause an increase in coral rubble on

a reef.

KEEPING A REEF HEALTHY

Most of the shallow coastal coral reefs are at the mercyof both man and nature. The accessibility of these reefs makethem open to exploitation by anyone; even people who cannot swim; through the effects of fishing, tourism, boat an-chorages, coastal pollution and construction etc. The shal-low coastal reefs also suffer greatly from the impact ofstorms and thermal events. In the event of increased sea

A diver floows thetransect line and takesnotes on the substrate

type under every 1/2meter and writes it

down on to a plastic

slate.

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Sample Substrate type categories for transects

LC Living coral Corals that are alive.

DC Dead coral Corals that had died recently and stillstanding in place. Where the shape of theold coral is clearly identifiable.

CR Coral Rubble Dead corals that have become fragmentedand has fallen on to the sea floor, includingun-attached coral pieces from the smallestto moderate sizes.

RK Rock underwater Rocks or very old dead coralareas where the substrate is still solid.

SS Sand stone Sand-stone or beach-rock areas.

SA Sand Sand, generally of a heavier grain size thatwill immediately fall to the bottom iflifted and dropped from the hand.

SI Silt Fine sand that would form a cloud of dustand fall down slowly if lifted and droppedfrom the hand.

Other organisms

AS Ascidians Any species of Ascidian, important in assess-ing invasive species.

CM Corallimorph Any species of corallimorphs

SP Sponges Any species of sponge

SC Soft coral Any leather or soft coral species

AL Algae Fleshy Algae

CA Coralline algae Coralline algae forming stone like surfaces

Note: These categories are indicated as a sample only and would often need tobe modified to suit local survey needs.

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tempreature the warmer sea water float nearer the sur-face over the cooler water beneath protecting the deepercorals.

The most convenient dumping ground for coastal gar-

bage is the sea. Most city garbage flows into the sea alongcanals and enters the sea and often end up getting washedup back on the beaches and on reefs. Garbage gets entangleson coral and kill them through rubbing on the coral andshading them from sun light; preventing them from photo-synthesizing. Polluted water causes lowered oxygen levelsin the water and is believed to be responsible for causing

disease and population blooms of reef organism which couldbecome invasive on coral.

The first step in helping a reef is to regularly clean thereef of the debris that entangles on coral, the polypropy-lene gunny bags and cast off fishing nets are among theworst offenders in this regard. Even the removal of theseentangling debris must be undertaken with much care as adiver need to be careful not to break the corals in the pro-cess. A small scissor can assist much in this regard. Coralsdo not like being touched and too much handling can dam-

Cleaningthe debrisentangledon coralswith asmall scissor.

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age their delicate tissue andcause them to catch infectionsand die.

The shallow coastal coral reefs suffer much throughphysical impact which causes corals to break or dislodge;these coral pieces would fall to the bottom and roll with thewaves. Few pieces would manage to re-settle on to the reef,most would eventually die. If these corals can be rescuedand re-settled on to the reef a significant improvement canbe made to the reef.

RESTORING CORAL COVER

The first step in thinking about restoration of a dam-aged coral environment is to assess the site, an understand-ing of the current status of the reef (site) in consideration aswell as collecting as much data as possible about the condi-tion of the reef before the degradation event should be keyfactors in deciding what action is appropriate. It is impor-tant to understand the cause of the degradation and if the

factors that lead to the destruction is still active or if it haspassed away, If the cause is not removed little will probablybe gained by attempted restoration efforts.

Garbage getting entangled oncoral can kill the corals if not

removed

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It must be important to a sensible reef restoration crewto attempt to bring a reef as close as practically possible toits former condition as bio-diversity, community composi-tion, structure and function both physical and economical.Setting up an arbitrary plan as the restoration target may

lead to less than desirable results.

A reef restoration plan needs to look at:1. Reducing further mortality of available coral2. Controlling reef degradation factors.3. Stabilization of dead reef surfaces and preventing

further decay

4. Fast Restoration of living coral cover of the reef.(using fast growing species)

5. Restoration of coral diversity (Species and Genetic)6. Restoration of the physical structure and surface

relief of the reef (creating micro habitats.)7. Restoration of non-coral diversity of the reef.8. Restoration of socio-economic functions of the reef.

Remaining reef surface area covered by living coralneed to be identified and steps should be taken to reduceany threats to them, diversity of species available currentlyon the reef must be identified and rarer species and spe-cies under threat must be identified, and if needed somemay need to be relocated on to a coral nursery for propa-gation. Species that was lost can sometimes be identified

through dead coral material available this would form thebasis on which any restoration attempt is to be undertaken.The composition of species used in restoration should ide-ally reflect the species present on the reef previous to thedegradation event. It is often not wise to introduce speciesfrom other reefs indiscriminately. Though some times itwould necessitate substituting different species to restore

the physical structure of the reef (Shape of corals massive,foliaceus etc.) when original species is not available.

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ASSESSING THE PHYSICAL CHARACTERSOF THE REEF

The reefs may contain outer reef crests, enclosing la-goons within (e.g. Hikkaduwa, Ahangama), be open withoutan outer wave barrier (e.g., Rumassala) or form off-shorebars (e.g., Kalpitiya, Basses)

The reefs contain different sub-zones with different en-vironmental conditions from Reef fronts/slopes regularly

pounded by sea waves, reef crests prone to heating and pe-riodic exposure to the sun etc. The sub-zones of the reefscontain different aggregations of animals and plants and res-toration need to follow this pattern. The flow of currents,depth, human use patterns, effects of sedimentation, pres-ence of invasive organisms and other factors need to betaken in to account in planning restoration.

The idea behind reef restoration activities is primarilyto re-build a reef to a state that existed on that reef prior tosome event that degraded it. Restoration activities are not

A smallcoral

nubinreplanted

on to areef. the

freshcement

base seenas gray

will soonb e

over-grown

with algaeand willblend in

with thereef

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primarily artificial reef building activities (though they couldbe used as supplementary techniques.)

The first step in planning an activity is to identify thecharacter of the reef prior to the degradation and set up a

target situation to which the restoration effort would tryto restore the reef to. Any reports or data available on be-fore situation would be the first source in understandingthis objective. The restoration workers next responsibilityis to look at the reef as a detective would look at a crimescene. The reef would yield an un-ending stream of evi-dence of what was there, when and how they were de-

stroyed, to a skilled observer.

Shallow reef crest

An open high relief reef with gullyformations Large poritis domes

Coral rubble area

R ee f E n v i r o n m en t s

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The second step is to identify priority areas where at-tention needs to be given; these follow the list of items givenbelow as the Restoration Plan.

Identify areas of surviving coral under threat

Identify reef degradation factors still active andfurther degrading the reef.

Identify dead reef surfaces prone to breaking up thatneed intervention to prevent further decay. (preserving available hard reef substrates)

Formulate a plan to restore/ rebuild live coral coverof the reef.

Assess coral biodiversity of reef prior and post todamage and identify threatened species for restoration and need for propagation in nurseries if needed.

Restoration of the physical structure and surface relief of the reef (creating micro habitats. Rebuildingreef structure by biological and/or physical means)

Restoration of non-coral diversity of the reef.(creating habitat diversity)

Restoration of socio-economic functions of the reef.(habitats for fishery species)

RESTORING LIVE CORAL COVER THROUGHREPLANTING

Degraded reefs contain many corals vulnerable to dam-age or death. A coral that is broken would often roll arounduntil the surface is abraded resulting in its death. Small coralpatches are vulnerable to invasion by invasive reef organ-isms; On a degraded reef the dead coral surface will soonbe overgrown with other organisms and would often beginto deteriorate and crumble within one to two years.

Damaged or destroyed coral areas can usually be re-stored by replanting the area with live coral material res-cued from among the broken coral or from areas where their

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survival is at risk. A third source is through selective prun-ing fully grown coral clumps where the coral had reached adense mass that does not allow fast growth any further.

Corals should be re-introduced to habitats where the

same species of coral would occur naturally, transferringcoral into different type of reef area should be avoided un-less it is certain that the coral would survive in the new habi-tat.

HANDLING CORALAll corals are sensitive animals and dislike being

handled, Care must be taken to minimize handling the coraland to touch them delicately when you must pick up andhandle coral. In most instances the bottom end of the coralwould be used as a attachment point for cementing backonto the reef and it is likely that a small area of live tissuecould get smothered in the process, as such it is wise tohandle the coral from the area that will be affected by ce-

menting.

Healthy corals are usually brightly colored and lookclean. If a coral looks pale, grayish, furry, swollen or cov-ered in thick mucous the coral is stressed and should beallowed to recover in a calm area for a few days beforehandling.

CORAL NURSERIESWhen coral units are small they are easily overrun by

other invasive reef organisms. It is often necessary to raisesmall coral colonies and rare coral species on a safer areabefore they could be re-settled on the reef. This can beachieved through transferring them onto constructed coral

nurseries for a while; where the corals would be safe fromattacks by invasive organisms. Coral nurseries could be con-structed as elevated racks made out of steel rods and mesh.

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The structuresshould stand 8"- 12"off the substrate onlegs that are difficultto be climbed by in-

vasive organisms.The structures needto be firmly anchoredinto the substrate andshould be resistant tobeing washed off withthe waves. The nurs-

eries should be regu-larly tended and any

unwanted organisms settling on them weeded. Once the coralcolonies have grown to about the size of a fist they are usallyready for replanting back on the reef.

REPLANTING CORAL

When suitable coral material is available, a site mustbe selected for replanting. Or conversely when a site hasbeen identified suitable coral material must be collected forreplanting to begin.

THE SITE SELECTIONThe selected site for replanting must be relatively free

from potential invasive organisms, sufficiently shelteredfrom heavy wave action, pollution, heavy siltation and anyother active destructive forces and should provide a stableand firm substrate. Coral rubble areas, murky waters andwave crests do not provide good homes to most corals. Sometimes it may be necessary to prepare the site and clean upthe substrate and stabilize any loose substrates before re-planting corals on to them.

Coralnurseries

provide atemporarysafe areato holdcoralbefore re-settlement

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FINDING THE RIGHT CORALSCoral pieces used for replanting should not be too small

if it is to be settled on to an uncontrolled environment. Theenvironmental needs of the species selected should matchthe conditions available at the settlement site (depth, wave

energy, siltation, presence of Invasive species etc.) Usuallymost of the required coral material can be picked up frombroken coral, from areas where destructive fishing prac-tices are in operation (common on most reefs) but any coralpiece that has a chance of naturally settling on to the loca-tion it is found should be left alone. It is better justifiedtotranslocate a coral piece in a position where its survival is

threatened. If a fixed piece must be removed it should al-ways be extracted from the center of a colony and not atthe periphery as the removed coral would re-grow fasterthan a piece removed from the periphery as it would slowdown the natural regeneration of coral.

Low growing wave resistant forms should survive bet-

ter in heavier surf areas, and species resistant to invasivespecies could be settled as a barrier line if a restoration siteis threatened by an Invasive organism (eg. Pocilloporadamicornis). If the substrate is a dead coral area that maybe prone to breaking up, faster growing coral species couldbe used to stabilize the area before diversity could be re-stored. Care should be exercised when introducing a fastgrowing species in to an already coral populated area wherethat species is not a natural part of a given reef. As the in-troduced species may out-compete coral species natural tothe reef.

The section on coral species would provide an over viewof the more important species available on the Southerncoastal area.

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Acroporacytheria

Ac ropo ra yo ng ei

A SELECTION OFCORALSPECIES USEFULL IN REEFRESTORATION.

There are over 180 species of corals recorded from SriLankan seas. These corals show diverse ecological and bio-

logical adaptations, requirements, preferences, capabilities,strengths and weaknesses. Some species are true to theproverbial coral ideal; slow growing and vulnerable; butothers could grow as fast as a weed would; with several spe-cies capable of growing over a centimeter per month. Somespecies are easily attacked by invasive species while othersshow considerable resistance. Some corals prefer thebrightly lit highly oxygenated waters of the reef crest andthe surf zone where they are resistant to high wave energy

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and periodic exposure to air during low tide, while othersprefer the relatively mild but safer waters further below.

Any attempt to restore a coral reef must begin with agood background as to the needs of each species of coral

and where each would be suitable. Most of these can be learnteasily by just looking around to see the natural occurrenceof corals on the reef. If you spend enough time observingcorals you would soon see the corals engage in many inter-actions with other life on the reef. Wars for space on thereef floor is common and in close proximity most organ-isms would compete or attack each other through physical

or chemical war fare. If one organism wins it will spreadover the loser, or if a stale mate is reached they would re-inforce the marginal area and co-exist. Observing these in-teractions would give a good understanding in to the abili-ties of each species of coral against other organisms on thereef and allow for a planned approach that improves sur-vivability of replanted coral. In addition to these basic guidelines it is always wise to re-settle a coral to an environmentthat is similar to the place where it came from. The decisionto transplant to a different environment must be with goodreason, as the chances of the coral not-surviving at that sitecould be higher.

With most species of coral it is best to re-plant clus-ters of the same species together so as to be able to form

larger confluent colonies when the re-plants grow and jointogether. The spacing of colonies about 20-30 cm. apartwould often lead to the colony growing together in about 1-2 years with the faster growing species.

It is not possible to give details of all the coral speciesthat would be encountered in restoration, but the following

pages offers an introduction to a selection of species usefulfor the beginner.

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A cr o p o r a f o r m o sa Staghorn coralThis coral dominated the Southwestern coastal reefs

prior to the 1998 Coral Bleaching /Mass mortality event.This is an ideal candidate for coral restoration as it is a veryfast growing species of coral that can usually survive frag-

mentation and actually uses fragmentation as a means offast colonization of sand substrates. The open branchingform of this coral also provides ideal habitat for the young ofmany reef fish species. The main set back is that this spe-cies had become almost extinct on many South-western reefspost to the 1998 bleaching event. When a translocation isattempted from the few reef sites it is currently surviving

in large enough quantities, theAcropora formosaseem togo into an extended acclimatization period lasting usuallyover a year before the coral will begin to grow normally. Iftranslocation is attempted it is important to translocate to atransit site on the destination reef that closely match theconditions of the donor site (temperature, salinity, turbid-ity etc.) and carry out the integration to the final site instages, giving the corals enough time to adjest to the newconditions without causing too much stress.

Acroporalianae

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Other larger branching A c r o p o r a speciesSeveral other Acropora species form thickets of

branches likeA.formosathough most of these do not formthe massive meadows that A. formosaformed before the1998 bleaching event. Some species likeA. yongei (see page

44)form excellent substitutes forA. formosa

Small branching A c r o p o r a speciesMany other Acropora species found on the reefs are

all good candidates for reef restoration. As each species hasits preference of depth and distance from shore look at thesite the corals are collected and tryto match the conditions when se-

lecting a site for replanting.

Acropora species do better aslarge singular mass colonies and itis usually a good idea to put a largegroup of the same species ofAcropora colonies together and

about 20-30 cm. apart so that inabout 2 years the colonies can be-come one unified colony.

Acroporalianae

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Table formingA c r o p o r a species

Several species ofAcropora grow as tablecorals and some species

can grow to over a meteracross . They form a spe-cialized reef habitat andis essential for somereef species such as theChevroned Butterflyfish(Chaetodon trifascialis)

The larger pieces ifavailable should be

mounted on sides of rocks horizontally or in some occasionsthey could be mounted vertically on inclined surfaces wherethey would take a longer time to grow vertically and thenform the horizontal table form.

M on t i p o r a a eq u i t u b er cu l a t a Rose /cabbage coralThis species was the only species that did not succumb

to the 1998 Bleaching event mostly surviving withoutbleaching; The species is one one the dominant species of

coral in Southernreefs and is also ca-pable of fast growthand fast colonization

from fragmenta-tion. This species isspecially usefull forrestoration of deadcoral areas.

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Po r i t es r u s.

This species of Porites forms clumps of small pencilsized frond-lets growing over an encrusting base; as thecolony grow of age the frontlets become more numerousand make a dense and tightly packed mass of fronds. The

colonies are usually dark brown to yellow ocher in color withpale or white tips to fronds. a single clump usually grows toabout 2ft in diameter but as the clumps grow in aggrega-tions this species can quickly cover large continuous sec-tions of the reef.

P. rusis a very fast growing species capable of spread-

ing through fragmentation. When naturally fragmented (bywaves etc.) a high percentage of fragments survive and arecapable of fast reat-tachment to sub-strate and shows agood capacity in re-colonizing reef en-vironments. Thisspecies is highlycompetitive and iscapable of settlingon to reef areas al-ready covered byturf algae spongesetc. The coral is re-

sistant to low den-sity aggregations ofascidians but wouldbe smothered by aggressive large Ascidian or corallimorphaggregations. it is also prone to attacks by a fine-branchedmat forming algaeHypnea sp., which would settle amongthe base of the frontlets of the coral and grow upwards till

the coral is shaded, smothered and eventually killed. Thesealgae in infestation stage can spread fast and do consider-able damage, but usually the invasive stage does not last

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for long periods and manual weeding with a small hook orsiphon devise could minimize damage. If algal removal isattempted it is important to ensure the removed materialis cleanly taken out of the reef as floating fragments can re-settle and kill more coral.Hypneadoes not seem to attack

other coral species.

The species prefers shallow to medium depths (from4ft to 15ft depth) with periodic moderate wave action. Inthe proper environment the speed at whichPorites ruscancolonize a dead substrate make it an ideal candidate as apioneer species to re-stabilize substrates before other

slower growing species could be introduced.

Dome forming Po r i t e s species.These are the real giants of the reef forming structures

as big as a small room that would date thousands of yearsold as these are among the slowest growing coral species.These species are of not much use to the reef restorer ex-cept; that the slow pace of growth and the importance ofthese to the physical structure of reef make them impor-tant elements in the reef preservation and demand atten-tion from the restorer to monitor and nurse them. Theselarge domes though resistant to ascidians are highly sus-

ceptible to coral diseaseslike the Pink-band diseaseand the pale-spot disease.

They do sometimes loseto spreading invasivecolonies of corallimorphsbut usually not without afight.

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Po c i l l o p o r a

d am i c o r n i u s andP . ver r u cosa

These brightly coloredsmall clump forming spe-

cies prefer the shallowerenvironments and can tol-erate extreme conditions ofthe reef crest. Though notas fast growing asP. rus orM. aequituberculata theycan grow fast and show

considerable resistance toenvironmental conditions and good survival, these speciesare among the most resistant to infestation of ascidians andcorallimorphs and is useful in creating a live barrier to stopspreading colonies of invasive species.

Po c i l l o p o r a ey d o u x i

(group) Elk-horn cor-als

This species ofPocillopora forms thickheavy branches and thick-ets that are good fish habi-tats. This species prefersthe somewhat deeper

zones of the reef, when oc-curring in shallow reefs itis always located in areaswhere there is exposure to

N.B.: This collection of species is only provided as a guide. Observation and

experimentation may reveal many more suitablecoral species for reef restoration.

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open sea water and is located at the outer reaches of a reef.Care should be exercised in using this species in shallow wa-

ter. The growth speed of the species is moderate and is amoody species that may not be a good species for initialreef substrate recovery.

Fa v i a andrelated speciesThese common reef species show moderate growth

speeds and are moderately hardy. They can be overrun byAscidians and corallimorphs. The colonies are usually wellcemented to substrate and fragmentation is difficult with-out damage unless broken pieces are found for replanting.

L e p t o r i a and P l a t y g y r a speciesThese meandroid corals are usually hardy andLeptoria

can be a reasonably fast growing species. These corals likethe favids are difficult to break for new planting material

but when broken pieces are found are good candidates.

Favi dcorals

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THE TECHNIQUE

The key to restoring a coral area is the success withwhich a coral can be re-attached to the substrate. Thereare many ways in which this could be achieved; coral pieces

can be settled on to slotted artificial substrates, wire-tiedon to reef surfaces or cemented/glued on to the reef base.The wire ties are the least effective system as this systemrelies on the coral unit growing and self attaching it self onto the reef. If the binding is firm this could be achieved inabout two weeks. But any slack that allows the minutestmovement of the coral could prolong this time to months.

The system also depends on finding locations on the reefthat allow a wire tie (preferably a plastic one) to find a goodgrip on the reef. The slotted artificial base is successful as acoral nursery, it fails as a final reef restoration technique initself as the structure can be easily seen and does not ho-mogenize with the reef and may disturb the aesthetics ofthe reef. Cementing corals on to reef substrates with ce-

ment or glue is possibly the best technique as the replantedcoral becomes part of the reef almost immediately post tothe replanting. Cementing corals underwater using fast set-ting low cost mixes of Portland cement is efficient when car-ried out by a trained crew. The side effects of these areinsignificant when the process is carried out properly withno adverse effects observed on replanted coral or the sur-rounding. Several glues both Epoxy and Cyanoacylates canbe used to fix very small coral units on to rocks that can besettled back on to reefs, but the higher cost of material,greater side effects, a more complex procedure and havingto expose the coral out of water for even brief time whilefixing the coral make these techniques less attractive thanbasic cement techniques.

The basic cement technique relies on speeding up thesetting time of Portland cement using additives to get a mix-ture that will harden within 1 -2 minutes from the time of

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mixing. The replanting site is pre-prepared and all the coralfragments used for replanting positioned at site. The cementwould be mixed on a float or boat close to the site and asmall ball of cement about the size of a tennis ball is sentdown wrapped in a plastic bag to prevent washing off in tran-

sit. On the sea floor the cement ball is taken out and appliedon to the reef surface in a single movement followed by thecoral unit being attached and fixed onto the cement mound.Care need to be taken not to over manipulate the cement asthis could cause cracks to form and allow salt water to runinto the mound and prevent it curing properly. And oncethe cement begins to set; initially it becomes brittle and if

handled break up in to a cloud of cement dust that will washover the reef. Some species of coral especially day feedinglong polyped species such as Gonioporacan be significantlystressed and even killed by cement dust if heavily exposedto it repeatedly.

Though the cement would setwithin minutes and not get washedoff; it will take another day or twoto achieve full curing and becomefully hardened. The settled coralsshould be left alone during thistime without disturbance.

cementingcoral ontoa reef andrecementedcoral at left

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It must be remembered that this technique is an ef-fective and efficient technique for re-planting coral IF CAR-RIED OUT BY SKILLED DIVERS. The advantages of thesystem relies mostly in the skill of the team carrying outthe replanting where almost no cement wash off will be

present. In the hand of careless or untrained operators thesystem will lose its advantages and could potentially be-come a danger to corals if a large amount of cement dust isallowed to get washed off in to the reef.

It must be stressed that though this book provides abasic introduction in to the techniques of coral restoration

it is in no way a complete manual. A restoration workermust be a good diver fully comfortable in the water, and beextremely aware of his surroundings and how his activitiesaffect the environment.

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RRRRREEFEEFEEFEEFEEF IIIIINVASIVENVASIVENVASIVENVASIVENVASIVE SPECIESSPECIESSPECIESSPECIESSPECIES -----ANANANANAN OOOOOVERVIEWVERVIEWVERVIEWVERVIEWVERVIEW

During the past few years signs of deteriorating reef health

was becoming more and more pronounced on the coral reefsof Southern Sri Lanka. These included infestations ofotherwise naturally occurring reef organisms spreading outof control, attacking and killing off considerable areas of livingcoral. The pattern of infestations sweeping across the reefareas and on most occasions dying out naturally within afew months may or may not be natural phenomena. But

due to the high levels of coral mortality caused by theorganisms while the infestation is active it is no longerconsidered an option to allow the infestations to run its cycleand control itself naturally. Most Corals are slow growingwith a growth of a few millimeters up to 15 cm recorded peryear. (Veron,1986) The problem is further aggravated asthe substratum lost to the infestation is soon covered by amyriad of competing reef organisms including turf algae,sponges, Corallimorphs, tubeworms, etc. reducing suitableground for new coral recruits to settle and re-colonize lostground.

A small coral unitin-situ on the reef;under threat froman advancing

infestation ofGreen Ascidians.

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The question should we interfere in reef ecology throughmanaging infestations is open to debate, Ideally in a pristineenvironment man has no role to modify the processes. Butthe reality is far from this ideal and man interferes with thereef ecology every day at many levels causing significant

threats to the reefs. In addition the live coral cover on thereefs have dropped to a level that is hardly able to sustainthe basic functions of a reef and any further loss of live coralcover is not an acceptable situation . On the terrestrialenvironments physical interference in managing invasivespecies is practiced in wide scale as an accepted managementpractice.

Competition for ground among reef benthic (bottom living)communities is naturally high. Coral polyps are usually wellcapable of fighting off attacking organisms and on mostoccasions will overgrow other reef organisms when buildingreefs. The recent spate of corals being killed by theseinfestations indicate that the corals have been weakenedand are no longer capable of keeping invading organisms atbay. The weakening of coral is believed to be the result ofhigh environmental stress caused by direct human activities,pollution and natural disasters. The changes in the reefspecies composition due to selective fishing is also a possiblecause as the loss of a controlling predatory species either asadult or larvae could lead to a bloom in a pray species.

CHRONOLOGY OF MAJOR REEF INFESTATIONS

IN SRI LANKA.

The earliest records of reef organisms attacking coral reefsin Sri Lanka involved the highly publicized phenomenonof the Crown of thorns Seastar (Acanthaster planci) thecoral eating starfish explosions devastated reefs from the

Great Barrier Reef to Malaysia and Maldives. In SriLanka infestations were reported in 1970s and 80s fromthe East coast and also on a few instances from the North-

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west reefs. The Seastar is common around Trincomaleand is considered a pest in the east coast and in the north-west; though infestations at the same scale is rarer in theSouthern coast.

The Polhena coral reef was destroyed by a populationexplosion of fleshy algae (Ulva spp.) overgrowing thecoral areas in mid 1980s the event was though to havebeen triggered by localized organic pollution of the area.(De Silva,1997) causing eutrophication.

In September 1996 the Rumassala Coral reef was

overrun by an infestation of a colonial Ascidian belongingto the family Didemnidae. Triggered by an unknownenvironmental signal the green Ascidians spread acrossthe reef overgrowing the living coral and even the fastgrowing calcareous algae Halimeda. By February 1997the infestation began to recede but not before killing anestimated 20% of the living coral cover of the reef withinthe short time span of 5 months. The damage was notsignificant as most of the damage was caused to areas ofAcroporid corals; these corals are among the fastestgrowing corals in the reef and showed significant re-colonization of damaged areas within a year. Similar butless intensive Ascidian infestations were documented insome other reefs Including Hikkaduwa. The Ascidianshave become one of the most persistent invasive species

over time and is now a regular species on most Southernreefs, causing periodic invasions followed by naturalrecession cycles.

In 1997-98 Infestations of the calcareous algaeHalimeda opuntiabegan to spread out of control on manySouthern reefs and within months overgrew and killed

significant areas of living coral. Hikkaduwa reef (De Silva,1997) and Unawatuna was among the worst hit by thisinfestation though strangely the Rumassala escaped with

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only minor damage. Some scientists are of the opinionthat this may be linked to petrochemical pollutants inthe water, though unproven; there may be correlationto the possible trigger, as Hikkaduwa reef regularly re-ceives significant amount of petrochemical pollutants from

the many boats within the lagoon. And the grounding ofthe ship M.V. Lord Nelson on Unawatuna reef and itsbreak up saw significant quantities of bilge oil enteringthe reef in the same year

An unidentified species of Black encrusting spongespecies claimed significant sections of the Rumassala reef

in 1998 just prior to the bleaching event. The speciesthough still active from time to time has not spread atthe same rate since 1998.

Post to the bleaching event the emerging reef domi-nant species of coralPorites ruswas being attacked by afine branched thicket forming algae (Hypnea sp.) whichlike the Halimeda settled itself at the base of the coralbranchlets and spread upward and over the coral block-ing the sun light (shading) and smothering the coral.Thisspecies can spread reasonably fast at infestation events.

The cause of increasing incidence of reef infestations withinthe past few years is not understood. The increasing levelsof coastal pollution and global climate change related envi-

ronmental stressors are believed to play a major role in re-ducing the defensive capacity of corals to fight off compet-ing organisms and infections. The trend in reef death hasreached alarming proportions within the past few years andunless serious action is initiated to control pollution ofcoastal seas the coral reefs of Sri Lanka may be extermi-nated within a short period of time.

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GALLERY OF REEF INVASIVE SPECIES

ANIMALSGreen AscidianThis small green colonial tunicate (Ascidian) belongs

to the Class Ascidiacea of the Phylum Chordata undersub-phylum Urochordata. There are a wide rangeofascidian species on coral reefs and usually causeno harm to corals. The Green colonial ascidianresponsible for infestations; form small greenelongate colonies less than a centimeter long andbelongs to the primitive family Didemnidae, The

identification of these ascidians beyond the level ofthe family is extremely difficult and the species inquestion is not identified.

The control of this species can take two forms.

The colonies are somewhat looselyattached to the substrate and can be physicallyremoved using a sharp tool. It is possible that theremoved colonies if allowed to float away couldre-attach and spread to other sites. Hence thedislodged colonies have to either be removed fromthe water or alternately the colony body must bebroken open which will on most instances kill thecolony. This method is best for managing small

areas (e.g. an attack on an important coral colony)

The green ascidians are photosynthetic witha symbiotic algae providing part of its nutritionlike in corals. Hence they are dependant on sun-light for survival, if the light supply is blocked forabout 2-3 weeks (using a sheet of black polythene

or similar) the Ascidians would usually becomebleached, weak and would often die. Care need tobe taken in using this kind of shading technique

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to control ascidians as, any corals getting cov-ered would also be affected by the loss of light.On a general note most corals are capable of sur-viving a two week shading better than ascidians

and would recover but all possible care should beexercised to keep corals exposed. It is also im-portant to allow some water movement underthe shade as not to kill off other organisms. Shadecontrolled Ascidians that are not killed would re-cover over time but usually their growth seem tobe stunted and the corals seem to be able to bet-

ter defend against the weakened Ascidians.

A colony of Poritesrus under attackby Green ascid-ians. Detail ofGreen ascidiancolonies (with a

Sea slug Philidiel la

sp. at left)

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Black SpongeThis encrusting black sponge species spreads as athin film over live corals and at the peak of aninfestation can cause significant damage to live corals.The identification of the organism is not certain, as

the very fine layer is difficult to collect for properidentification but contain spicule types consistent withsponges, It would not be too improbable if withfurther investigations this organism is found to belongto a different taxonomic group. The sponge canweaken and kill corals of most species though largedome corals seem to be resistant. It is impossible to

control the spread as the layer of sponge is too thinand adheres hard on to the substrate making it almostimpossible to remove physically, no other controlmeasure has been devised yet, though infestationsdo not last for more than one to two months andspread at a moderate pace.

Inva si ve black spongespreading over and killingcorals in Rumassala reef in1997. the above area ofcoral was killed within aspan of one month

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CorallimorphThe brown Corallimorph which spread over anyavailable hard surface on the reef is developing as athreat to reef corals. This species appear like a thickbrown wooly towel. This close relative of coralsshares many characters with corals but does not buildlimestone skeletons. Biologically they are very similarto corals and also contain symbiotic photosyntheticalgae in their tissue.

Control of Corallimorphs can be achieved byphysically removing them using a scraper; the

colonies are easily damaged and killed, but if releasedwithout being killed there is a possibility of re-settlement and colonizing at other locations. It istherefore ideally needed to remove colonies fromthe water, When corallimorphs are damaged theyrelease

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