in the spring of 2008 an eighty-four footpleasure boat departed from ft. lauderdale bound for the caribbean.thirty miles south of miami, it strayed from marked navigation channels into the shallowwaters of biscayne national park. suddenly, running at full speed it collidedwith a coral reef near elliot key. corals, sponges and sea fans were instantlyobliterated as the boats twin propellers plowed through the reef.the engines were disabled and the powerless vessel drifted in the wind until groundingon a second reef. here, the wind and waves rocked the boat onits hull, shattering the ancient coral mounds and pounding the reef into rubble.a coral reef that had taken centuries to grow
was destroyed in just moments.two and a half years later, coral researchers and resource managers are searching for solutionsto help the oceans declining coral reefs. can new technologies and naturally occurringbiological mechanisms help restore the lost coral communities? and can ecological balancebe returned to floridas coral reefs? major funding for this program was providedby the batchelor foundation, encouraging people to preserve and protect americas underwaterresources. biscayne national park is an undersea gardenfilled with multi-colored sponges, corals and sea fans. at the northern extent of theflorida keys reef tract its sea grass beds, coral reefs and mangrove shorelines covermore than 170,000 acres a gem in the national
park system, but an area with a history ofdamaging boat groundings. corals in biscayne national park and on aglobal scale are in a serious state of decline due to stresses like climate change, diseaseoutbreaks and overfishing. since the late 1970s close to ninety-eightper cent of staghorn and elkhorn corals have disappeared from the reefs in florida andthe caribbean. because corals are having such a difficulttime persisting, resource managers want to restore boating impacts like the 2008 groundingsite in the park. when the vessel grounded it crushed up thesurface of the reef into a rubble field and were trying to use a combination of adhesivesto stabilize that rubble. were collecting
the rubble into mounds like this and likethis and well be using a combination of cement and natural sponges that are found right hereon the reef to bind this rubble to stabilize it through time. right now the rubble moundsare in the process of being put together. were installing rebar stakes like this thatwill help us monitor them through time and well be looking at things such as coral recruitment,the stability of the mounds themselves, if they change in size and shape and height,and well probably monitor theses for a period of at least five years.researchers at the university of miami have developed one of the first underwater applicationsfor mosaic imaging, a technique comparable to aerial photography on the land. this technologywill create useful perspectives of the coral
reef and grounding site in biscayne nationalpark. the diver swims back and forth in a lawnmower-like pattern recording overlappingimages of the underwater landscape. later, at the university laboratory, a single seamlessimage of the reef is produced. this is basically an unprecedented baselinein terms of the amount of information you can get in a very short amount of time.three-dimensional images can be created over time to show reef areas where corals growbest, the places where restoration is most likely to succeed.new growths of soft corals and sponges are returning to the grounding site, but the boatsmost damaging impacts are still evident. the damage extends several hundreds of squaremeters and really theres no easy way to document
that. here were able to use the video andthe stills to really cover the entire area both the affected area and also the communityaround it so we know what this area should look like when its fully restored.coral reef restoration gained traction in the florida keys national marine sanctuarywith marine biologists like harold hudson, the reefdoctor, and ken nedimeyer. hudson, a restoration specialist for the sanctuary, perfected adesign for reef modules that were used for the structural repair of a large vessel groundingsite, the wellwood, on molasses reef near key largo. nedimeyer performed the biologicalrestoration with transplanted corals grown in his undersea nursery. his restoration planwas validated when it was discovered that
the transplants on the reef were spawningseveral years sooner than expected. i was real excited, i thought man, this isamazing because this is exactly what weve been trying to say that were going to do whichis re-establish these spawning populations of corals. it brought a whole new life tothe possibility of not just putting corals back on the reef but re-establishing breedingpopulations that could then re-populate other downstream areas.nedimeyers coral nursery is the largest in the country and a model for many coral aquaculturists.here you encounter a hundred rows of coral fragments mounted on concrete blocks. eachcoral is attached to a disc with a label designating its origin and genotype, or genetic properties.more than a thousand staghorn cuttings are
strung from six line nurseries suspended inthe water column by floats and cross-tied with horizontal lines.on a line nursery they grow down, they grow to the side, they grow all different directions.and another thing thats nice about them, if a turtle or a shark or a fish bumps againstthem on the line they just bounce out of the way and they swing right back to where theywere. if a turtle bumps against a coral thats firmly mounted on a disc itll break it off.nedimyer cultivates staghorn coral, one of the principle reef building corals and onelisted as threatened under the endangered species act. he cultivates them in his nurseryfor a year then transplants them to the reef. one of the things we need to be doing is preservingthe genetic diversity that we still have.
and if we dont preserve as much of that aspossible right now we wont have anything to work with in ten or fifteen years.research associate tom capo and colleagues at the university of miamis experimental hatcheryare preserving the genetic diversity of orphaned corals whose survival was threatened by storms,boat groundings and anchor pulls. some were recovered from the grounding site in biscaynenational park. researchers are trying to answer questions about a destructive phenomenon knownas coral bleaching. whats going on? is it disease? is it somesort of water quality parameter? and many of these questions cannot be answered easilyin the field. so the goal is to have a coral genetic bank, a coral resource that we canprovide genetically maintained strains of
coral to people, bona fide researchers aroundthe world so that they can look at these problems, at these issues, and look at them in a scientificway. in a partnership between biscayne nationalpark and the university of miami, trained volunteers assist capo with a labor-intensiveprocess known as fragmentation to produce a large number of small coral specimens.you should have one ready for him now, i mean he should not stop.travertine plates are marked, drilled and fitted with passive integrated transponders,or pit tags, that will give each coral a unique identity.the large corals are cut into fragments, each about an inch-and-a-half in diameter. thebottom surface is shaped on a tile saw. the
fragment is thoroughly dried, super-gluedto a pit tag plate and cataloged for future reference.half of the fragments will be transplanted at the coral restoration site in biscaynenational park, the other half will remain at the facility for monitoring and lab studiesto help capo and coral researchers answer another difficult question.how can we enhance all of this to make the only reef tract in the continental unitedstates a viable place rather than seeing it deteriorate like its been doing over the pastten years? one of capos research partners, martin moe,a marine biologist in the florida keys, believes he has an answer.in 1983, there was this tremendous plague
and it hit only one organism. and that wasthe long-spined sea urchin, diadema antellerum that occupied all the reefs of the caribbean,the bahamas, florida, they were all very densely occupied by diadema. and diadema peformedthe essential task of cleaning the algae off the reefs and conditioning the substrate sothat it would accept and encourage coral growth and the growth of many kinds of fish and invertebrates.within one year 98% of all the diadema antellerum from the mouth of the panama canal all theway up to bermuda were history, were toast. they all died quickly.at first, divers like ken nedimeyer were happy about the decline of the sharp-spined creatures.as much as i dont like getting stabbed by them, theyre important and i want to havethem back.
like sheep grazing in a pasture, diadema seaurchins graze the macroalgae that grow on the reefs and inhibit coral reproduction.a lot of the problems are directly related to the sea urchins.if you fix all of the water quality issues and fix all of these other things but youdont fix the sea urchin problem youre not going to have a coral reef. sea urchins playa really important role. ken and i came to the point of view that theloss of the diadema was critical to the decline of the reefs. now, our coral reef declinecomes from many factors not just the loss of diadema. but that is certainly one of themost critical elements because its the diadema that maintain that balance between coral andalgae growth.
with support from the florida keys nationalmarine sanctuary, nedimeyer and moe did two experimental reef studies where they re-introducedthe diadema. a year later, the findings were remarkable.juvenile corals increased by more than 150%, coralline algae, which encourages coral settlementand growth, was sharply higher, and macroalgae was reduced from 11% to less than 2%. i started with the florida board of conservationmarine laboratory back in 1962. florida was a very different place back then. i workedwith the keys and the keys were magical. i remember going out and diving around johnpennekamp area and there were huge stands of elkhorn coral, palmatta, beautiful. andit was such a tremendous environment. and
when i came back in the late 90s the reefwas so much different and it was so sad to see what was a glorious coral environmentjust become for the most part a lot of algae covered rocks.it seemed like the best thing that i could do was to work with the diadema because nobodyelse was doing it and it was something essential to do.martin moe is committed to perfecting the technology to reproduce, or culture diademain the laboratory. today he begins a new culture process, or run by selecting diadema thatare ready to spawn. immersing them in a tub of warm water stimulates the spawn.oh yeah. now thats a male. you can see the white sperm there. yes sir, thats a female.weve got spawning first three. how about that?
ok, this is the product from the spawn. apparentlya male and a female both went which means that i should have eggs in here. oh yes, thatis nice. i can see fertilization membranes are present around every egg so we know wevehad a good spawn. we know weve got good eggs. out of, lets say, five million eggs that werespawned here, which is a pretty good estimate, and out of those five million youd probablybe lucky if one, or two made it, in nature, all the way through the process and becamea juvenile. and then youd be lucky if one of those survived into adulthood, very luckyactually. the following morning he counts the developingembryos. the eggs hatch in about 24 hours or so, 18-24hours, they become blastulas, they become
prisms which is the initial urchin shape.the embryos are transferred to three larvae culture tanks where they will eat and growfor the next thirty-five to forty-five days. but, unlike other types of invertebrates,diadema larvae will die if they settle on the bottom of the tanks. finding a methodto mimic the natural ocean current to keep the larvae in suspension had been martinsbiggest trial during his early culture attempts. maintaining a sterile environment had beenanother problem. entire runs had failed in the culture tanks. the weeks ahead will againtest his system and the diademas ability to survive.meanwhile, the fragmented corals from the university of miami have arrived at the groundingsite in biscayne national park. volunteers
swim with buckets of cement and crates oftiles to the transplant areas. another group has re-attached broken pieces and transplantednursery-raised coral to the site. and resource managers are betting on the feasibility ofa new restoration technique. were going to be using sponges to bind therubble that was created by this grounding incident and this is the first time weve triedthis and to our knowledge the first time sponges have been used in an actual restoration projectfor this purpose. sponges are known to play an ecological rolein binding rubble in a natural reef setting. theres also evidence that coral will settleand grow more favorably on an area thats been bound by sponges.right here weve marked a sponge where we cut
a fragment off yesterday. weve tagged andmarked the parent colony so that we can track it through time and see how that lesion healsjust to make sure its doing ok. the sponge fragment we took from there weve attachedover in our sponge nursery. each tile has nine pvc trees. we attach one sponge fragmentto each pvc tree. we cut these sponge fragments off the parent colonies that i showed youearlier. were trying to get the cut surface in contact with the paver stone at least asclosely as possible. our colleagues have shown that those cut surfaces bind to whatever theyrein contact with, very quickly if all goes well. so we hope to come back and see thesesponges growing down onto the tiles and also up starting to branch out. and the idea isthat in time once the sponges grow and start
getting larger that you can then cut fragmentsoff of these and use them in restoration projects. we tried to get all of our fragments cut toapproximately ten centimeters in size. we harvested these fragments yesterday and someof them are starting to show a slightly blackish color. were not sure if thats a good thingor a bad thing. were going to be watching these sponges carefully on a daily basis inthe beginning and then probably every week or so to see how they survive and grow.when they started to turn black we started to get very concerned, not knowing if we haddone something wrong, or not knowing if we had potentially killed all these sponge fragmentswe had harvested. however we were very relieved to see that even the next day the blacknessgoes away, the sponges are doing great, and
they appear to be re-attaching very quicklyto both the rubble pieces that theyve been attached to and also to the grow out structures.for forty days martin moe has been monitoring the survival and growth of the diadema larvae.a week ago, he hit a setback - all three cultures were struck by an infestation of vorticella,an organism that causes competition for food and a decline in the larval development. but,one of the cultures showed a larger number of well-formed larvae than the other two.he made a decision to dedicate the remaining food supply to the survival of the well-formedculture and abandon the others. it might be the only chance for at least some of the larvaeto reach the settlement phase. now this one is ready to come out, and wecan check for settlers on it. and they settle
as larvae and then they go through metamorphosisin which all the spines and larval tissue all drop down into the rudiment and the rudimentbecomes a little round juvenile. and you can pull it out of the settlement, like this,and the water stays in these little cubicles, then you put it right down into the settlementtray. the water in the settlement tray is all adjusted for temperature, ph, alkalinity,calcium, and its ready to support the process of metamorphosis and the early juvenile.after they go through metamorphosis theyre a soft little creature. and they cant surviveas a soft little creature. they have to pull calcium carbonate, the same stuff your bonesare made out of, out of the water, which is dissolved in the water, and they have to formtheir hard parts and their mouth parts so
that they can actually scrape and feed andsurvive as a sea urchin rather than a pelagic floating larvae. and then it can be carriedand placed down into this raceway kind of facility. i call it a raceway, theres a watercurrent that moves through the whole tank like this, and as they are settling thereit keeps the water fresh and clear around them. they grow and become little urchinson these plates. at some point it becomes optimum to pick the plate up and put it ina bucket, theyll stay stuck on the plate, then you can move them to any kind of a growout area that you wish. after four years of developing the technologyto raise lab cultured diadema, martin moe is nearing the end of his quest.
when we get to the point where we can producelarge numbers of juvenile diadema then we can begin to research on what is the bestway to re-establish them on the reef. at that point, along with kens work with the coralsand what ive been able to develop with the diadema, we can come together and we can achieveat least some semblance of ecological restoration on the reefs.at the grounding site the sponge transplants are healthy and growing. amanda bourque iswatchful as the sponges replicate their natural behavior in a transformed environment. but,it will take several years of monitoring before the success of this project is fully known.coral reef restoration is an emerging science built on innovative ideas, lessons learnedand continual refinement of the human technologies
that are helping nature restore its gardensof the sea.
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