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>>NARRATOR: 
  Reaching up into the water

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like the branches of trees, 
  they are thousands of organisms

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living together as one.

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And together they provide 
  shelter and protection

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for many more.

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>>This is really important 
  for a lot of different

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marine organisms and provides 
  a refuge for these organisms.

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>>NARRATOR: 
  Once a common sight,

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elkhorn and staghorn corals 
  were the dominant

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shallow reef building corals 
  in the Caribbean and Florida.

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>>Coral reefs are under 
  extreme stress toda

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from a variety of causes, 
  both globally and locally.

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>>In the past 30 years, 
  elkhorn and the staghorn

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have declined dramatically, 
  between 90% and 98%,

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throughout the Caribbean.

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They're now listed 
  as threatened under

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the U.S. Endangered 
  Species Act...

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>>And are much reduced 
  from their former glory.

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>>NARRATOR: Primarily, disease 
  as well as some other factors

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has led to the drop in numbers

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of elkhorn and staghorn 
  colonies.

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But while these corals 
  have declined in recent years,

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their hybrid appears 
  to be increasing

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in parts of the region.

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>>What's really cool 
  about this hybridizing system

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is that the hybrid is not found 
  in the fossil record.

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They seem to be 
  increasing recently,

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likely due to the decrease 
  in the parental species.

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>>NARRATOR: Often found in 
  really shallow water,

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this hybrid, commonly called 
  fused staghorn,

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closely resembles its parents.

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>>You have some that look 
  very much like staghorn

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and then others 
  that look like elkhorn.

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Most of the ones that I've seen 
  throughout all my study sites

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in the Caribbean have more 
  of a staghorn look to them,

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but they're more tightly clumped 
  than the branching staghorn.

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>>NARRATOR: Could these hybrids 
  be better equipped

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at dealing with 
  environmental stressors?

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Might they be filling 
  a niche left behind

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by the decline of their parents?

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>>   Major funding for this 
  program was provided

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by the Batchelor Foundation, 
  encouraging people

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to preserve and protect 
  America's underwater resources.

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And by Divers Direct, 
  inspiring the pursuit

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of tropical adventure 
  scuba diving.

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>>NARRATOR: Dr. Nicole Fogarty 
  is an Assistant Professor

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00:03:12,325 --> 00:03:14,294
at Nova Southeastern 
  University's

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00:03:14,294 --> 00:03:19,599
Oceanographic Center.

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She studies the hybrids 
  at various sites

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across the Caribbean.

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>>I was really interested 
  in this hybridization

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between these two 
  threatened species.

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There's very little that's known 
  about the hybridization.

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>>NARRATOR: Since 2005, 
  she's been making

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regular research trips 
  to a small island

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off the coast of Belize.

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>>The island is out on 
  the Mesoamerican Barrier Reef,

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so you really can literally 
  roll off the island

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and be on a coral reef.

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There's just a very nice reef, 
  very, very close to the island.

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>>NARRATOR: The Mesoamerican 
  Reef stretches along

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the coasts of Mexico, Belize, 
  Guatemala and Honduras.

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It is considered 
  the largest barrier reef

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in the Western Hemisphere, 
  covering nearly 700 miles

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from the northern tip 
  of the Yucatan Peninsula

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down to the 
  Honduran Bay Islands.

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Carrie Bow Cay is located 
  15 miles offshore

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from the Belizean town 
  of Dangriga.

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It has been a research facility 
  of the Smithsonian Institution

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since 1972.

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>>We just celebrated 
  our 40th year anniversary,

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and we've got 
  over 930 scientific publications

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that have come from the island, 
  including a few books

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that have all resulted 
  from the work at Carrie Bow.

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It's really contributed a lot 
  to our understanding

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of coral reef ecosystems 
  in the Caribbean.

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>>NARRATOR: The island is an 
  ideal place to study the hybrid

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because of its proximity 
  to all three types of corals.

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>>There's a wonderful 
  population just off

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the southern end of the island.

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It has both the staghorn,

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the elkhorn and the hybrid 
  of those two species.

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>>NARRATOR: 
  When Nicole first started coming

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to Carrie Bow Cay, she wanted 
  to understand why the hybrids

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might be increasing in numbers.

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>>One possibility 
  is that there's

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an actual increase 
  in hybrid formation,

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so the egg and sperm 
  of staghorn and elkhorn

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are mixing to form an embryo 
  that's a hybrid

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that will eventually 
  go and settle and grow

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into an adult hybrid coral.

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The other possibility 
  is that we have an increase

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in asexual fragmentation.

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These corals 
  are branching corals,

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and so they can break off 
  and fragment, reattach

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to the bottom and then 
  continue to grow.

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So that's a very 
  important aspect

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of their life history stage.

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So you could imagine 
  if there's just a few rare

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hybrid events that formed 
  decades ago, these hybrids

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could just fragment repeatedly 
  over the years.

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The other possibility 
  is that the hybrid

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00:07:00,887 --> 00:07:04,724
is actually more viable 
  than the parental species

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00:07:04,724 --> 00:07:07,260
and might show 
  increased fitness.

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It's called "hybrid vigor."

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And so we have hybrids that have 
  been established over the years.

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And when you have 
  the disease outbreak

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and disturbance and other things 
  that have led to the decline

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in the parental species, 
  the hybrid's actually able

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to withstand all those 
  different events.

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And that's why 
  they're increasing in numbers

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and are higher in abundance 
  at some of the sites.

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>>NARRATOR: 
  To test these hypotheses,

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Nicole decided to conduct 
  a number of experiments

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when the corals were spawning.

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>>Staghorn and elkhorn coral 
  only spawn once a year,

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usually in late summer-- July, 
  August, or September.

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So that means one night 
  out of the year, they release

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gamete bundles, 
  and those gamete bundles

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are full of both egg and sperm.

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Each individual polyp 
  that makes up a coral colon

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will form one gamete bundle.

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It takes the polyp 
  about nine months

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to create the egg 
  and about six months

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to create the sperm.

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So there's a lot of energy 
  being invested in forming

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these gametes.

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The gamete bundles are released 
  in one synchronized pulse.

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They float up to the surface, 
  break apart, mix with

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other gametes from 
  other individual corals

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from the same species, 
  or sometimes hybridize,

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and then fertilization occurs 
  at the surface.

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The resulting embryos 
  then float around

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for a couple of days 
  before developing into larvae.

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And then the larvae 
  will float around

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for a few more days 
  before they start swimming

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down to the bottom, looking for 
  a good place to settle.

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They'll attach to the bottom, 
  metamorphose, and grow into

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an adult coral.

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>>NARRATOR: 
  Staghorn and elkhorn corals

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are very plantlike creatures.

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>>And so really, when you're 
  thinking about corals,

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even though they're animals, 
  their evolutionary background

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and evolutionary trajectory 
  are much more like plants.

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They are hermaphrodites.

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They are attached to the bottom 
  just like adult plants are.

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They broadcast spawn their 
  gametes like many plants do.

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They're long-lived like plants, 
  and they also can

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asexually fragment.

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They asexually propagate 
  like many plants.

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>>NARRATOR: 
  Using a tentlike net,

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Nicole collected the gametes of 
  both elkhorn and staghorn corals

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on the nights 
  they were spawning.

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>>We bring those gametes 
  back into the lab.

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We can separate the gametes 
  out to sperm and stock solution

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and then we can play 
  "mad scientist," where we do

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all kinds of different 
  fertilization assays.

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Now that we've separated them 
  out into our sperm

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and egg solutions, we're going 
  to conduct a series

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00:10:00,100 --> 00:10:02,435
of fertilization experiments.

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And so, we're looking 
  at fertilization between

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the elkhorn and the staghorn, 
  and this is crosses between

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the staghorn eggs 
  and the elkhorn sperm.

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And now I am going to add one 
  milliliter of eggs to the vials.

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After I complete this cross, 
  then we'll do

166
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the reciprocal cross 
  and mix staghorn sperm

167
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with the elkhorn eggs.

168
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And then we can do it 
  with sperm competition.

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That's when we mix 
  both the staghorn

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and the elkhorn sperm together 
  and then introduce the sperm

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to the staghorn eggs 
  or introduce the sperm mixtures

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to the elkhorn eggs.

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And that's more likely 
  what occurs during

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coral spawning, because 
  these species spawn

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at the same time,

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and so the sperm 
  are going to be mixing,

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competing for who's going to 
  actually fertilize the eggs.

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Once all the crosses are done, 
  we'll let them sit

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for three hours and then 
  we'll score fertilization.

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00:11:04,130 --> 00:11:06,199
When we score fertilization, 
  what we are looking for

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00:11:06,199 --> 00:11:10,003
is the number 
  of unfertilized eggs

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and the number 
  of dividing embryos.

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>>NARRATOR: With these 
  fertilization experiments,

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Nicole tried to determine 
  if there may be

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gametic incapability, 
  which means one species' sperm

186
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can't fertilize 
  the other species' eggs.

187
00:11:29,255 --> 00:11:31,457
>>What we found out 
  is that both the staghorn eggs

188
00:11:31,457 --> 00:11:34,360
and the elkhorn eggs 
  are able to hybridize,

189
00:11:34,360 --> 00:11:37,530
but the elkhorn eggs 
  are a little more resistant

190
00:11:37,530 --> 00:11:40,033
to hybridization 
  than the staghorn eggs.

191
00:11:40,033 --> 00:11:42,402
The staghorn eggs 
  can be fertilized

192
00:11:42,402 --> 00:11:47,507
by the elkhorn sperm just as 
  easy as their own species sperm.

193
00:11:47,507 --> 00:11:51,711
In the sperm competition assays, 
  we found the similar result.

194
00:11:51,711 --> 00:11:54,147
The eggs of elkhorn 
  are a little more resistant,

195
00:11:54,147 --> 00:11:57,450
and then the eggs of staghorn 
  are more easily fertilized

196
00:11:57,450 --> 00:11:59,519
by not only their 
  own species sperm

197
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but the elkhorn sperm, as well.

198
00:12:01,654 --> 00:12:03,957
So it can happen 
  in both directions,

199
00:12:03,957 --> 00:12:06,226
but hybridization occurs 
  more frequentl

200
00:12:06,226 --> 00:12:07,694
with the staghorn eggs.

201
00:12:17,670 --> 00:12:20,673
>>NARRATOR: Next, Nicole 
  looked into the viabilit

202
00:12:20,673 --> 00:12:24,277
of the hybrids.

203
00:12:24,277 --> 00:12:27,447
>>The hybrid might be sterile, 
  such as the mule example,

204
00:12:27,447 --> 00:12:29,482
when a donkey and a horse mate.

205
00:12:29,482 --> 00:12:33,353
Or it might just be inviable, 
  so it has decreased fitness,

206
00:12:33,353 --> 00:12:35,822
and it's not able to persist 
  in an environment.

207
00:12:35,822 --> 00:12:38,258
Perhaps it's more 
  susceptible to disease

208
00:12:38,258 --> 00:12:40,460
or temperature fluctuations.

209
00:12:40,460 --> 00:12:43,596
So these are the type of things 
  that I wanted to look at.

210
00:12:43,596 --> 00:12:45,198
And what we found 
  was that the hybrid

211
00:12:45,198 --> 00:12:47,634
was not inferior across 
  any life history stage

212
00:12:47,634 --> 00:12:49,002
that we looked at.

213
00:12:49,002 --> 00:12:51,771
That includes the larval stage, 
  during settlement,

214
00:12:51,771 --> 00:12:54,707
throughout metamorphosis, 
  and also as an adult.

215
00:12:54,707 --> 00:12:57,110
We also found that 
  hybrids can persist

216
00:12:57,110 --> 00:12:59,112
in the shallow 
  marginal environments

217
00:12:59,112 --> 00:13:01,681
they're often found, 
  but also can persist and grow

218
00:13:01,681 --> 00:13:04,684
in the parental species habitat 
  without a problem.

219
00:13:14,661 --> 00:13:17,597
>>NARRATOR: And Nicole made 
  another interesting discover

220
00:13:17,597 --> 00:13:21,968
at her study site in Belize.

221
00:13:21,968 --> 00:13:23,936
>>The hybrid, even though 
  they're often in just

222
00:13:23,936 --> 00:13:27,540
two or three feet of water, 
  are no more likely to bleach

223
00:13:27,540 --> 00:13:31,010
than the parental species 
  that are in deeper water.

224
00:13:31,010 --> 00:13:34,814
And so this could be 
  that the hybrid is more tolerant

225
00:13:34,814 --> 00:13:38,651
of fluctuations in temperature-- 
  not only increase in temperature

226
00:13:38,651 --> 00:13:41,154
during the summertime, 
  but those shallow areas

227
00:13:41,154 --> 00:13:44,390
also cool off really quickly 
  during the wintertime.

228
00:13:44,390 --> 00:13:47,627
And there's also a lot of UV 
  irradiance blasting those corals

229
00:13:47,627 --> 00:13:49,929
in that really shallow, 
  clear water.

230
00:13:49,929 --> 00:13:52,231
So that's something that I'm 
  going to be exploring further.

231
00:13:59,205 --> 00:14:01,607
>>NARRATOR: Coral bleaching 
  occurs when the animals

232
00:14:01,607 --> 00:14:03,810
are very stressed.

233
00:14:03,810 --> 00:14:07,580
There are a variety of stressors 
  that can cause bleaching,

234
00:14:07,580 --> 00:14:11,517
including exposure 
  to extreme temperatures.

235
00:14:11,517 --> 00:14:13,920
Extreme temperatures 
  are likely going to increase

236
00:14:13,920 --> 00:14:18,758
in frequency in the future 
  because of climate change.

237
00:14:18,758 --> 00:14:20,893
>>Coral bleaching is when 
  the corals lose

238
00:14:20,893 --> 00:14:23,763
their symbiotic dinoflagellate 
  that's in the tissues

239
00:14:23,763 --> 00:14:25,231
of the coral.

240
00:14:25,231 --> 00:14:28,234
So corals have 
  a symbiotic relationship

241
00:14:28,234 --> 00:14:31,604
with a dinoflagellate 
  we call zooxanthellae,

242
00:14:31,604 --> 00:14:33,940
and the zooxanthellae 
  is in the coral tissue.

243
00:14:33,940 --> 00:14:38,010
It gives the coral the golden 
  or brown colors that you see.

244
00:14:38,010 --> 00:14:40,813
And what occurs 
  is when the coral

245
00:14:40,813 --> 00:14:43,983
gets stressed out, 
  that symbiotic relationship

246
00:14:43,983 --> 00:14:45,618
is going to break down.

247
00:14:45,618 --> 00:14:48,054
And so they lose 
  that zooxanthellae,

248
00:14:48,054 --> 00:14:51,457
and then what you see 
  is the white coral skeleton

249
00:14:51,457 --> 00:14:53,659
through the translucent tissues.

250
00:14:53,659 --> 00:14:56,095
Now the dinoflagellate, 
  the zooxanthellae,

251
00:14:56,095 --> 00:14:58,765
is important for the corals 
  because it gives the corals

252
00:14:58,765 --> 00:15:00,700
a lot of its nutrition.

253
00:15:00,700 --> 00:15:03,369
Corals can capture 
  small zooplankton

254
00:15:03,369 --> 00:15:06,239
in their tentacles, 
  but most of the nutrition

255
00:15:06,239 --> 00:15:09,375
that the coral gets 
  is through the zooxanthellae.

256
00:15:09,375 --> 00:15:11,811
So when the symbiotic 
  relationship breaks down,

257
00:15:11,811 --> 00:15:14,847
the coral is going to have 
  decreased growth rates,

258
00:15:14,847 --> 00:15:18,418
it's going to have reduced 
  reproductive capabilities,

259
00:15:18,418 --> 00:15:21,687
and so it's going to really 
  negatively affect the coral.

260
00:15:29,695 --> 00:15:32,598
>>NARRATOR: one thing that 
  is still unknown at this point

261
00:15:32,598 --> 00:15:39,205
is whether or not the hybrids 
  can mate with each other.

262
00:15:39,205 --> 00:15:41,407
>>We know that hybrids 
  aren't sterile because

263
00:15:41,407 --> 00:15:44,076
from the molecular signature, 
  we know that the staghorn

264
00:15:44,076 --> 00:15:46,379
and the hybrid can mate.

265
00:15:46,379 --> 00:15:49,182
>>NARRATOR: However, to date, 
  no second generation of hybrids

266
00:15:49,182 --> 00:15:51,050
has been discovered.

267
00:15:51,050 --> 00:15:52,785
>>There's a couple 
  of different hypotheses

268
00:15:52,785 --> 00:15:55,087
of why we might not see 
  a second generation,

269
00:15:55,087 --> 00:15:58,224
one of which is that the 
  sampling effort was pretty low.

270
00:15:58,224 --> 00:16:00,393
It was only at three 
  geographic sites

271
00:16:00,393 --> 00:16:02,261
and pretty low sample size.

272
00:16:02,261 --> 00:16:04,897
So perhaps second generation 
  hybrids are out there,

273
00:16:04,897 --> 00:16:06,899
but it'll take further sampling, 
  and that's something

274
00:16:06,899 --> 00:16:09,168
I am looking at 
  as part of my research

275
00:16:09,168 --> 00:16:12,138
at Nova Southeastern University.

276
00:16:12,138 --> 00:16:14,774
The other possibility 
  is that if hybridization

277
00:16:14,774 --> 00:16:20,213
is increasing, as I believe 
  it is, then we might have

278
00:16:20,213 --> 00:16:23,182
more generations 
  in the decades to come.

279
00:16:23,182 --> 00:16:26,185
It's just such a new event 
  that they're increasing

280
00:16:26,185 --> 00:16:29,388
in numbers that they haven't had 
  an opportunity to create

281
00:16:29,388 --> 00:16:32,158
a second generation.

282
00:16:32,158 --> 00:16:35,828
What's really interesting 
  about this system is that

283
00:16:35,828 --> 00:16:38,064
the parental species 
  are found in the fossil record

284
00:16:38,064 --> 00:16:40,333
for millions of years, 
  but the hybrid

285
00:16:40,333 --> 00:16:41,868
has no fossil record.

286
00:16:41,868 --> 00:16:45,671
So it's a relatively recent 
  event, and there is evidence

287
00:16:45,671 --> 00:16:47,673
that it is increasing 
  in some sites.

288
00:16:47,673 --> 00:16:50,877
There are sites in Belize, 
  in Curacao, in Florida

289
00:16:50,877 --> 00:16:53,279
where we know the hybrid 
  was not at that site

290
00:16:53,279 --> 00:16:56,249
just five years ago, and now 
  we see hybrids there.

291
00:16:59,552 --> 00:17:01,053
We also know 
  from genetic studies

292
00:17:01,053 --> 00:17:03,990
that the hybrid populations 
  are composed of

293
00:17:03,990 --> 00:17:07,360
multiple genotypes, meaning 
  that there are separate

294
00:17:07,360 --> 00:17:09,395
hybridization events 
  that have occurred

295
00:17:09,395 --> 00:17:12,131
and not just one 
  rare hybridization event

296
00:17:12,131 --> 00:17:15,067
that has asexually fragmented.

297
00:17:15,067 --> 00:17:17,770
What I think is currently 
  going on in this system

298
00:17:17,770 --> 00:17:20,172
is that, with the decline 
  of the parental species

299
00:17:20,172 --> 00:17:22,975
over the past 30 years, 
  we actually have an increase

300
00:17:22,975 --> 00:17:24,343
in hybridization.

301
00:17:24,343 --> 00:17:26,913
And how that would work 
  is that if you imagine back

302
00:17:26,913 --> 00:17:30,349
before the 1980s, 
  you had really extensive

303
00:17:30,349 --> 00:17:33,052
thickets of both staghorn 
  and elkhorn.

304
00:17:33,052 --> 00:17:35,021
They were the primary 
  reef builder in the shallow

305
00:17:35,021 --> 00:17:36,956
reef environments.

306
00:17:36,956 --> 00:17:40,660
And so when staghorn or elkhorn 
  spawn, the eggs

307
00:17:40,660 --> 00:17:42,228
are immediately going to be 
  swamped

308
00:17:42,228 --> 00:17:44,597
by their own species' sperm.

309
00:17:44,597 --> 00:17:47,533
And occasionally you might have 
  had hybridization

310
00:17:47,533 --> 00:17:49,635
if a couple of the eggs 
  went unfertilized,

311
00:17:49,635 --> 00:17:51,771
but it was a pretty rare event.

312
00:17:51,771 --> 00:17:54,774
Well, now you have these 
  populations of elkhorn

313
00:17:54,774 --> 00:17:57,843
and staghorn that are 
  really sparse, and so if you can

314
00:17:57,843 --> 00:18:00,279
imagine when they spawn, 
  the eggs are going to go

315
00:18:00,279 --> 00:18:01,847
unfertilized.

316
00:18:01,847 --> 00:18:03,549
And at least with 
  the staghorn eggs,

317
00:18:03,549 --> 00:18:04,951
whatever sperm they run into,

318
00:18:04,951 --> 00:18:08,187
whether it's their own species' 
  sperm or an elkhorn sperm,

319
00:18:08,187 --> 00:18:09,722
that's going to fertilize it.

320
00:18:09,722 --> 00:18:12,592
So, we have this increase 
  in hybrid formation

321
00:18:12,592 --> 00:18:16,929
because the parental species 
  have decreased in numbers.

322
00:18:38,451 --> 00:18:40,753
>>NARRATOR: Long-term 
  monitoring is necessar

323
00:18:40,753 --> 00:18:46,792
to truly understand the changes 
  occurring on the reef.

324
00:18:46,792 --> 00:18:49,295
>>Only through long-term 
  observations over time

325
00:18:49,295 --> 00:18:51,831
can you evaluate and find 
  new discoveries, and I think

326
00:18:51,831 --> 00:18:54,967
it's paid off in a big way.

327
00:18:54,967 --> 00:18:57,703
>>NARRATOR: 
  In 2011, Nicole created

328
00:18:57,703 --> 00:19:01,941
a demographic study 
  off the south end of the island.

329
00:19:01,941 --> 00:19:04,543
>>As far as we know, 
  we're the only demographic stud

330
00:19:04,543 --> 00:19:07,146
Caribbean-wide that looks at 
  both the elkhorn, staghorn

331
00:19:07,146 --> 00:19:09,115
and the hybrid.

332
00:19:09,115 --> 00:19:11,851
We established 
  seven circular plots,

333
00:19:11,851 --> 00:19:13,686
and these are permanent plots.

334
00:19:13,686 --> 00:19:16,589
So every three to four months, 
  we go back and look at

335
00:19:16,589 --> 00:19:18,924
every individual elkhorn, 
  staghorn or hybrid

336
00:19:18,924 --> 00:19:20,092
in these plots.

337
00:19:31,837 --> 00:19:36,208
>>NARRATOR: Each of the seven 
  plots has a buoy at its center.

338
00:19:36,208 --> 00:19:38,611
>>And then we took 
  a transect line and extended it

339
00:19:38,611 --> 00:19:41,213
seven meters from the center.

340
00:19:41,213 --> 00:19:43,816
We then tagged every single 
  coral colon

341
00:19:43,816 --> 00:19:48,387
within that seven-meter radius 
  in that circular plot.

342
00:19:48,387 --> 00:19:51,057
We also mapped it, 
  and how we do that is

343
00:19:51,057 --> 00:19:53,359
we take the transect line 
  from that center buo

344
00:19:53,359 --> 00:19:56,662
and extend it out 
  to the focal colony.

345
00:19:56,662 --> 00:19:59,565
And then someone at the center 
  buoy has a compass,

346
00:19:59,565 --> 00:20:02,368
looking at their compass, 
  and then will give us

347
00:20:02,368 --> 00:20:05,938
the different numbers 
  for that compass bearing.

348
00:20:05,938 --> 00:20:08,307
Whoever is at the focal colony 
  will then write down

349
00:20:08,307 --> 00:20:11,277
the distance from 
  the center buoy, and then also

350
00:20:11,277 --> 00:20:13,579
that compass bearing 
  that the person at the center

351
00:20:13,579 --> 00:20:15,481
then gave them.

352
00:20:15,481 --> 00:20:18,684
That way, we can mark 
  each individual coral colon

353
00:20:18,684 --> 00:20:19,852
and where it is.

354
00:20:23,856 --> 00:20:25,624
>>NARRATOR: 
  Next, tissue samples were taken

355
00:20:25,624 --> 00:20:29,061
for genetic analysis.

356
00:20:29,061 --> 00:20:31,497
>>We take small tissue 
  samples-- about a centimeter,

357
00:20:31,497 --> 00:20:34,333
just like the very end 
  of your pinky.

358
00:20:34,333 --> 00:20:37,636
It's only about one month 
  of growth for these corals,

359
00:20:37,636 --> 00:20:40,239
so it doesn't hurt the corals 
  at all.

360
00:20:46,846 --> 00:20:50,249
We take that tissue sample 
  and preserve it.

361
00:20:50,249 --> 00:20:52,218
Then we take it back 
  to the laborator

362
00:20:52,218 --> 00:20:56,222
and we use micro-satellite 
  markers to be able to genotype.

363
00:20:56,222 --> 00:20:59,892
And then that gives us an idea 
  of how many separate genotypes

364
00:20:59,892 --> 00:21:02,895
are in our population 
  and how man

365
00:21:02,895 --> 00:21:07,867
of the different colonies are 
  actually from asexual fragments.

366
00:21:07,867 --> 00:21:11,270
So far, we have nearly 
  600 corals tagged and followed

367
00:21:11,270 --> 00:21:13,706
over that period of time.

368
00:21:13,706 --> 00:21:16,909
The elkhorn coral out there 
  is really genotypically diverse.

369
00:21:16,909 --> 00:21:19,245
We have over 30 genotypes 
  out there.

370
00:21:19,245 --> 00:21:22,615
The staghorn 
  is less genotypically diverse

371
00:21:22,615 --> 00:21:25,985
and there's only a couple 
  unique genotypes, and the hybrid

372
00:21:25,985 --> 00:21:28,621
has about four or five 
  unique genotypes.

373
00:21:37,163 --> 00:21:39,398
>>NARRATOR: Nicole based 
  her demographic stud

374
00:21:39,398 --> 00:21:42,868
on a protocol designed and used 
  by other scientists

375
00:21:42,868 --> 00:21:44,970
in the Caribbean.

376
00:21:44,970 --> 00:21:48,507
>>We can compare our results 
  in the Western Caribbean

377
00:21:48,507 --> 00:21:50,810
with their results 
  in Florida and elsewhere

378
00:21:50,810 --> 00:21:52,378
in the Eastern Caribbean.

379
00:21:52,378 --> 00:21:55,147
Every three to four months, 
  we come back and we photograph

380
00:21:55,147 --> 00:21:57,082
each individual colony.

381
00:21:57,082 --> 00:22:00,486
We also assess each individual 
  colony and so see if there's

382
00:22:00,486 --> 00:22:04,723
any damselfish bites, 
  see if there's any predation,

383
00:22:04,723 --> 00:22:08,527
coral bleaching, disease, 
  et cetera.

384
00:22:08,527 --> 00:22:12,031
>>NARRATOR: Nicole also takes 
  length, width and height

385
00:22:12,031 --> 00:22:16,402
measurements of each individual 
  colony and then estimates

386
00:22:16,402 --> 00:22:20,873
the percentage of live coral 
  for each colony.

387
00:22:20,873 --> 00:22:23,742
>>We're also interested in how 
  quickly these corals grow.

388
00:22:23,742 --> 00:22:27,213
So what we do is we take 
  a beaded cable tie and put it

389
00:22:27,213 --> 00:22:30,616
about two centimeters away 
  from the tip of the coral.

390
00:22:30,616 --> 00:22:35,221
The coral grows from the end, 
  and so it will continue to grow

391
00:22:35,221 --> 00:22:38,824
and extend so we can measure 
  from that beaded cable tie

392
00:22:38,824 --> 00:22:42,294
to the very end of the coral 
  and see how much it grows

393
00:22:42,294 --> 00:22:46,065
every time period that we 
  come out here and sample.

394
00:22:46,065 --> 00:22:48,968
We're going to be doing 
  a lot of spatial analyses

395
00:22:48,968 --> 00:22:51,871
and being able to look 
  how disease spreads

396
00:22:51,871 --> 00:22:55,741
across this population 
  and coral bleaching, predation,

397
00:22:55,741 --> 00:22:58,811
and see how that changes 
  year after year and how it

398
00:22:58,811 --> 00:23:01,380
affects different colonies 
  and may spread

399
00:23:01,380 --> 00:23:03,115
to neighboring colonies.

400
00:23:09,588 --> 00:23:11,790
>>NARRATOR: In the few 
  short years that this project

401
00:23:11,790 --> 00:23:14,927
has been ongoing, 
  Nicole has already made

402
00:23:14,927 --> 00:23:18,297
several interesting discoveries.

403
00:23:18,297 --> 00:23:21,734
>>We established this project 
  just a few months before

404
00:23:21,734 --> 00:23:24,270
a major disease outbreak.

405
00:23:24,270 --> 00:23:26,772
The other aspect is that 
  we've already lost

406
00:23:26,772 --> 00:23:30,109
individual genotypes 
  from that disease event,

407
00:23:30,109 --> 00:23:33,178
and lastly we're seeing 
  some new recruits--

408
00:23:33,178 --> 00:23:35,414
at least colonies that we think 
  are new recruits.

409
00:23:35,414 --> 00:23:37,983
Once they get a little bit 
  larger, we'll be able to take

410
00:23:37,983 --> 00:23:39,785
a tissue sample 
  and genotype them

411
00:23:39,785 --> 00:23:42,254
and verify that it's 
  a unique genotype

412
00:23:42,254 --> 00:23:46,959
compared to the rest of the 
  individual colonies out there.

413
00:23:46,959 --> 00:23:48,694
>>So, it's really 
  a valuable data set.

414
00:23:48,694 --> 00:23:51,297
There's nothing else quite like 
  it in the Western Caribbean.

415
00:23:51,297 --> 00:23:53,999
There is some similar monitoring 
  going on in the Florida Keys,

416
00:23:53,999 --> 00:23:58,537
and also in the Virgin Islands, 
  but this will add a new data set

417
00:23:58,537 --> 00:24:01,307
for a region, the Mesoamerican 
  Barrier Reef Region,

418
00:24:01,307 --> 00:24:05,611
which is really 
  much less explored.

419
00:24:05,611 --> 00:24:08,414
>>What we ultimately would like 
  to do is put this data

420
00:24:08,414 --> 00:24:10,149
into population models.

421
00:24:10,149 --> 00:24:12,751
And so, then, we can determine 
  whether this

422
00:24:12,751 --> 00:24:17,489
particular population is stable, 
  increasing or decreasing.

423
00:24:20,326 --> 00:24:23,696
>>NARRATOR: There are still 
  many questions left unanswered

424
00:24:23,696 --> 00:24:26,498
that Nicole hopes to study.

425
00:24:30,769 --> 00:24:33,005
>>Because the elkhorn 
  and the staghorn corals

426
00:24:33,005 --> 00:24:36,909
are the only current threatened 
  species in the Caribbean,

427
00:24:36,909 --> 00:24:39,678
it's really important 
  that we have a better handle

428
00:24:39,678 --> 00:24:41,180
of what's going on with them

429
00:24:41,180 --> 00:24:43,248
both from an ecological 
  standpoint

430
00:24:43,248 --> 00:24:46,118
and also an evolutionary 
  standpoint.

431
00:24:46,118 --> 00:24:48,988
And so this information 
  not only will provide

432
00:24:48,988 --> 00:24:52,858
some data needed to understand 
  the evolutionary trajector

433
00:24:52,858 --> 00:24:55,394
of these species, but also 
  what's going on

434
00:24:55,394 --> 00:24:58,063
from the ecological perspective.

435
00:24:58,063 --> 00:25:01,500
If the hybrid is more tolerant 
  to increased temperature

436
00:25:01,500 --> 00:25:04,870
or UV irradiance, 
  then it's going to be able

437
00:25:04,870 --> 00:25:08,340
to withstand some of these 
  harsh environmental changes

438
00:25:08,340 --> 00:25:12,678
that we may see associated with 
  global climate change.

439
00:25:12,678 --> 00:25:16,015
If we lose one or both 
  of the parental species,

440
00:25:16,015 --> 00:25:18,584
it will be interesting to know 
  if the hybrid can reproduce

441
00:25:18,584 --> 00:25:23,155
among itself and can provide 
  a genetic reservoir

442
00:25:23,155 --> 00:25:25,958
for some of these genes 
  that we have lost

443
00:25:25,958 --> 00:25:30,763
through the extinction 
  of the parental species.

444
00:25:30,763 --> 00:25:34,967
>>It's an avenue that's worthy 
  of research and may provide

445
00:25:34,967 --> 00:25:37,369
some great information 
  on how coral reefs

446
00:25:37,369 --> 00:25:40,873
can be restored and thrive 
  in the future.

447
00:26:17,976 --> 00:26:20,646
>>   Major funding 
  for this program was provided

448
00:26:20,646 --> 00:26:24,016
by the Batchelor Foundation, 
  encouraging people

449
00:26:24,016 --> 00:26:30,756
to preserve and protect 
  America's underwater resources.

450
00:26:30,756 --> 00:26:35,027
And by Divers Direct, 
  inspiring the pursuit

451
00:26:35,027 --> 00:26:39,027
of tropical adventure 
  scuba diving.