Aquarium researchers and staff are on expedition to the remote Phoenix Islands Protected Area (PIPA) to study the natural history of the islands, surrounding reefs and connecting open water ecosystems. Research on the 2015 expedition will directly inform the management and maintenance of this world-renowned MPA. Today's post comes from the expedition's chief scientist in the field Dr. Sangeeta Mangubhai.

The Carondelet seamount sits in over 5000 meters of water, 65 miles southeast of Nikumaroro Atoll. Scientists from the New England Aquarium have attempted to dive this seamount three times, and each time we have been beaten back by large waves pounding on the top of the seamount. This time I made two special requests to the ocean navigation Gilbertese goddess Nei Manganibuka. Firstly, that she keep each and every diver safe while in the Phoenix Islands. And secondly, that she send us calm seas for the journey home so that we could safely dive and document the marine life on Carondelet seamount.

We all set our alarms at 6 a.m. and got up in the dark—tired and bleary-eyed. Remember, at this point we have been working 24 days straight. As the sun rose everyone was hanging off the top deck straining to find the seamount. I got my wish for calm seas, but that meant that there were no waves breaking on the seamount to let us know its actual location. Captain Jens from the Hanse Explorer had two different GPS coordinates for the site from two different maps, and neither was correct. My heart sank. This was looking for a needle in a very big haystack!

As the sun rose further, we saw a patch of pale blue about 800 meters ahead of us. Around this blue, waves were peaking, and ahead of us a school of fish starting jumping out of the water. We had found the seamount!

Descending to the seamount | Photo: Craig Cook

We dropped in on the top of the seamount, which is about 6 meters below the ocean surface, and headed straight down to 18 meters. The reefs reminded me instantly of some of the smaller islands in the Phoenix group. The coral community was dominated by massive and submassive colonies of Faviids and Porites species. Pounded by the ocean on all sides, the corals don’t grow very high, and almost hug the surface of the seamount. The diversity was not particularly high, with only 13 genera of coral recorded during our two dives. As we headed into the shallows, the coral cover decreased, though there were hundreds of small branching Acropora coral recruits scattered on the top of the seamount.

Old fishing line | Photo: Craig Cook

Professor Stuart Sandin, who did a rapid assessment of the fish diversity on Carondelet seamount, said the fish life was similar to what he has recorded on this trip throughout the Phoenix Islands group. He documented at least 150 species of fish over two dives. White tip sharks cruised around the shallows and slopes, and an aggregation of grey reef sharks kept to deeper water. However, the shark life was much lower than expected, suggesting the seamount may have experienced shark fishing sometime in its history. We found evidence of old fishing line on the seamount, strangling corals, trailing down the slopes.

As we head now back to Apia, Samoa, I cannot help think about how vulnerable remote seamounts are in the Pacific, and how much the management is lagging around these important habitats. Thanks to the efforts of the Kiribati government, the seamounts in the Phoenix Islands Protected Area are fully protected. They truly are a wonderful gift to humanity.

Aquarium researchers and staff are on expedition to the remote Phoenix Islands Protected Area (PIPA) to study the natural history of the islands, surrounding reefs and connecting open water ecosystems. Research on the 2015 expedition will directly inform the management and maintenance of this world-renowned MPA. Today's post comes from Aquarium veterinarian Julie Cavin.

The Phoenix Islands Protected Area is home to green turtles and hawksbill turtles, who make nests on remote PIPA beaches. Though there are reports of green turtles in PIPA dating back approximately 50 years, and in 2000 and 2002 hawksbill turtles were definitively identified in PIPA as well. Thus far, no other turtle species have been observed in PIPA. However, green turtles are especially numerous. In 2000 and 2002, reports of approximately two green turtles were observed per dive, with evidence of nesting on many of PIPA's islands.

"During the past few weeks, we have seen countless numbers of sea turtles at most of the PIPA islands." 

During the past few weeks, we have seen countless numbers of sea turtles at most of the PIPA islands. Similar to earlier reports in 2000 and 2002, we often see two to five turtles during a dive or while fishing for sharks from the zodiac; a few times we have even counted up to ten turtles on the surface at one time. We have also observed evidence of nesting behavior on some of the beaches (i.e., turtle tracks in the sand and disturbed dirt indicating a nest).

Dr. Julie Cavin and Camrin Braun working to free an endangered green sea turtle from entanglement  (Photo: Darren Coker)

"Camrin noticed a juvenile green turtle (Chelonia mydas) that had been significantly entangled in fishing net in a pile of net and rope." 

Today was a different turtle encounter, however. While searching for shark fishing sites, we were exploring the shipwreck on McKean that is in very shallow water and onto the beach. There is a large debris field accompanying the wreck including portions of the ship as well as some of the ship’s likely contents. Camrin noticed a juvenile green turtle (Chelonia mydas) that had been significantly entangled in fishing net in a pile of net and rope. Luckily it was alive and seemed to be in good condition. We carefully cut all of the line free from its neck and front and rear flippers. 
There were no deep wounds from the tightly wound net and the turtle was alert and in good body condition, so the entanglement had likely occurred within the past few days at most, possibly even within the last high tide. I walked it out to shallow water and watched as it quickly swam toward the open ocean. Hopefully he/she will continue to thrive and become a member of the breeding population of this endangered species.

Aquarium researchers and staff are on expedition to the remote Phoenix Islands Protected Area (PIPA) to study the natural history of the islands, surrounding reefs and connecting open water ecosystems. Research on the 2015 expedition will directly inform the management and maintenance of this world-renowned MPA. Today's post comes from the expedition's chief scientist in the field Sangeeta Mangubhai.

A juvenile frigate bird watches the team curiously (Photo: C. Young)

File photo of a whale shark | ©Brian Skerry

 

Hermit crabs communicate with each other on McKean, oblivious to the whale shark sighting (Photo: C. Young)

Sam Payet grew up in a small town on the North-West coast of Australia where he spent much of his childhood fishing, diving and camping. He lived here until the age of 15, before moving to the South-West region to finish high school. Owing to his fascination with the ocean, Sam enrolled to study Coastal and Marine Science at Curtin University, Perth. Upon finishing his Bachelor Degree, Sam completed an honours year where he studied hybridising reef fishes at Cocos and Christmas Islands in the Indian Ocean. Sam is currently a research intern at King Abdullah University of Science and Technology (KAUST) in Saudi Arabia, he hopes to build on his experience before considering a PhD in the near future. Sam’s main interests are fisheries ecology, conservation.

Aquarium researchers and staff are on expedition to the remote Phoenix Islands Protected Area (PIPA) to study the natural history of the islands, surrounding reefs and connecting open water ecosystems. Research on the 2015 expedition will directly inform the management and maintenance of this world-renowned MPA. Today's post comes from Rob Lasley.

Kamil Kemer, the ship’s Turkish boson, knows what he’s doing. With over 20 years of experience at sea, he is full of knowledge on knots, weather and beyond. “Secure everything tonight... The sea is no joke,” Kemer said one evening before going to bed. A couple hours later, the ship rolled like mad. He was right. He knows the sea. And yet, every day when I return to the Hanse Explorer with dead coral heads and begin the slow process of chiseling out every small animal that lives inside, Kemer looks on with wonder. “How is there so much life?” he asked. The question, from someone so familiar with the ocean, is inspiring. I cannot even begin to answer it, especially not in a short blog, so I’ll focus on why the question arose: the life. Biodiversity, that is, and there is a lot of it.

Photo: Sangeeta Mangubhai

A typical day on the Hanse begins with an early morning splash onto a reef after a short ride on a Zodiac (everything before that is grogginess and daze). Most folks, scientists included, focus on what is apparent immediately after the splash: the charismatic reef fish, sharks aplenty (small ones, moms), and corals of numerous types, textures, colors, and morphologies. However, to resist these immediate treasures and to sink and shrink below, into deep crevices and between lobes of living and dead corals, is to find where most marine diversity lies. Squirming, writhing, snapping and clicking, invertebrates make up the bulk of marine diversity. There are millions of species. Many or most are completely unknown, and at best they are only known as a name, without any additional information on diet, behavior, evolution, etc. As such, marine invertebrate biodiversity is as mysterious as deep outer space, except with abundant life of every conceivable shape and color.

"My job is to document the unknown invertebrate diversity of the Phoenix Islands." 

My job is to document the unknown invertebrate diversity of the Phoenix Islands. The task is impossible, but try we must, and science has shaped the goal into something reasonable and quantitative. On each island, one of my responsibilities is to collect dead coral heads. This probably sounds like a weird thing to do, but I can explain. The skeleton of many types of corals, such as Pocilopora, comprise numerous flattened, finger-like projections and lobes. When a coral head dies, its hard skeleton remains, and the nooks and holes between the lobes are prime real estate. Everybody wants to move in. After a few postmortem weeks or months, a dead coral head will be full of snapping shrimp, porcelain crabs, cone snails, polychaete worms, and many, many relatives. Collecting and documenting these diverse apartment buildings from the fore reef of each island provides a good slice of comparable biodiversity.

Rob extracting cryptic inverts from a dead coral head (S. Mangubhai)

So every morning, I SCUBA-scour the reefs of PIPA in search of the right dead coral heads—the right species, the right size, the right depth, the right time since death, just right. This takes time. Then I return to the Hanse and chisel away, removing every squirmy little tenant. This takes more time. Much more. Hours and hours, deep into the night, I extract every living thing from the coral heads. Tons of animals make their homes in dead coral heads. They literally fall out when I set the dead coral head on the deck of the Hanse. Each specimen is documented, photographed, and preserved. Back on land, the preserved specimens from the trip will be identified, and fauna from different islands will be compared. The dataset will also be compared with similar efforts east and west of us, from the Line Islands to the Philippines to the Red Sea.

"All of these dead-head collections will give scientists an idea of how populations of species are connected through the vast oceans, what species occur where and why, and where species are the most abundant and diverse." 

All of these dead-head collections will give scientists an idea of how populations of species are connected through the vast oceans, what species occur where and why, and where species are the most abundant and diverse. Furthermore, specimens collected during the trip will be catalogued at the Florida Museum of Natural History and will provide valuable material for taxonomic and other studies. In fact, all of the material collected will be available for loan to scientists anywhere and accessible online—photos, geographic coordinates, habitat information—meaning that our 2015 PIPA collections will aid in scientific research for as long as the specimens are preserved and the data remain available online. This means the PIPA 2015 dead head specimens, and others collected during the cruise, could potentially inform environmental and biodiversity science for a hundred years, or more. Pretty good stuff, if you ask me.

Returning to the question, “how is there so much life?” I can’t fully answer that, but I can tell you that coral reef diversity is grand and full of surprises and beauty, and much of it remains unknown and ripe for discovery by able seafarer and scientist alike.

Aquarium researchers and staff are on expedition to the remote Phoenix Islands Protected Area (PIPA) to study the natural history of the islands, surrounding reefs and connecting open water ecosystems. Research on the 2015 expedition will directly inform the management and maintenance of this world-renowned MPA. Today's post comes from the expedition's co-leader on land Randi Rotjan.

One of the best things about working in and with the Phoenix Islands Protected Area is the close-knit relationship between science and management. Since the first New England Aquarium Expedition in 2000 (before the protection of the archipelago was even a twinkle in anyone's eye), Aquarium scientists and affiliates have been going to Tarawa to relay scientific findings directly to the Kiribati Government. This tradition continues today, and the relationship has grown; the scientists now have a formal outlet to communicate findings and provide scientific advice to PIPA Management via the Scientific Advisory Committee. Transit to PIPA is expensive and time-consuming, and thus infrequent. So, when an expedition is going, we will often try to accomplish both scientific and management objectives. This trip, the main management objective is to install signs on each island that state the MPA rules.

The first sign was installed on Kanton, with the help of Kanton residents. It's a big task, requiring a deep hole, wire mesh, poured concrete and a lot of sweat and patience.

Installing signs on Kanton Island (Photos by Aranteiti Tekiau)

Installing signs on Rawaki Island (Photo by Sangeeta Mangubhai)

Proud and hot (Photo by Sangeeta Mangubhai)

Note: No Landing Permitted! (Photo by Sangeeta Mangubhai)

Randi

Aquarium researchers and staff are on expedition to the remote Phoenix Islands Protected Area (PIPA) to study the natural history of the islands, surrounding reefs and connecting open water ecosystems. Research on the 2015 expedition will directly inform the management and maintenance of this world-renowned MPA. Today's post comes from researchers Darren Coker.

Kanton Island is a relatively large atoll with an expansive and shallow lagoon. The single entrance to the lagoon provides the perfect playground for manta rays riding the currents as the lagoon fills and drains with the tides. Manta rays (Manta birostris) are threatened megafauna and in 2006 were listed as a Near Threatened species by the IUCN. The population at Kanton Island provides a unique opportunity to study these animals within a protected and geographically isolated area.

Manta ray in PIPA | Photo: Shawn Harper

The out flow of water from the lagoon contains nutrients that are re-suspended and washed out by the increased currents. To track the localized movement patterns of these large majestic rays within the island’s lagoon and fringing reefs, small acoustic tags are attached to the top of the ray. These tags emit a signal that is unique to each individual and received by a network of hydrophones (acoustic receivers) dotted around the island. Researchers ride the out going tides through the lagoon entrance on snorkel looking for manta rays. Once spotted, color patterns and size are noted before attaching the tag with the use of a hand spear. The tag is inserted into the thick dorsal muscle and aside from getting a fright the tag causes no harm. The tags can stay attached to the ray for several years, transmitting valuable data about their movements every few minutes.

Manta ray in PIPA | Photo: Shawn Harper

Little is known about manta ray movement patterns and what regions of the reef and lagoon are used. The movements of these manta rays will help us understand population connectivity and movement patterns around the islands. Movement and migration behavior of individuals can reveal key ecological characteristics and population dynamics of a species. This is particularly important for pelagic species that occur within the Phoenix Islands protection areas and beyond its boarders.

— Darren

Darren Coker, PhD, was born in New Zealand but spent some of his childhood in the Solomon Islands and England. His love of traveling later took him to Australia where he learned to dive on the Great Barrier Reef. Since then, Darren completed a Bachelor of Science in Marine Biology at James Cook University (JCU) and a PhD at the ARC Centre of Excellence for Coral Reef Studies (JCU) and the Australian Institute of Marine Science in Townsville, Australia. Following his PhD, Darren worked at the ARC Centre of Excellence for Coral Reef Studies investigating the effects of climate change on commercially important reef fishes. He joined the Reef Ecology Lab at KAUST as Postdoctoral Fellow in spring 2014. Darren’s research interests include investigating the importance of live coral habitats for fishes and how changes in habitat condition following disturbances impact the abundance, recruitment, and behavior of associated reef fishes. He is also investigating the role ecological processes play in biogeographic patterns of Red Sea reef fishes.

Aquarium researchers and staff are on expedition to the remote Phoenix Islands Protected Area (PIPA) to study the natural history of the islands, surrounding reefs and connecting open water ecosystems. Research on the 2015 expedition will directly inform the management and maintenance of this world-renowned MPA. Today's post comes from Chip Young. 

Humankind is changing the world’s oceans and the coral reef ecosystems within. Because these changes are happening across the globe at varying rates, how does a concerned citizen develop an understanding of what a healthy coral reef ecosystem “should” look like? We are a group of scientists currently studying the reefs of the Phoenix Islands Protected Area (PIPA), a 407,112 km2 region of islands, atolls, seamounts and open ocean set aside by the Kiribati government to serve as a marine protected area. As scientists, it is relatively easy to assess whether or not coral reefs have been negatively affected by human activities. A more difficult assessment is determining how physical, biological and chemical factors (in the absence of human impacts) intertwine, resulting in a pristine coral reef ecosystem, the type of marine environment people generally think a reef “should” look like.

Phoenix Islands Reefs have higher coral cover and higher fish biomass than many other reefs in the region. (Photo: Craig Cook).

  
For the last two weeks, I have been working with a team of scientists from the Woods Hole Oceanographic Institution (WHOI) collecting coral cores from Porites spp.

Chip Young cores from a large Porites coral colony. (Photo: Hanny Rivera)

A historical record of growth can be observed in a “plug” or core retrieved from an individual coral colony. Similar to a tree’s growth rings, corals form bands that often relate to annual growth. The skeletal density of each band and the amount of growth between bands (extension rate) reveal a record of what conditions the coral colony has experienced through its lifetime and how it has responded. Did the marine environment challenge growth or did it promote growth and on what time scales? The physical and chemical environments in which the coral colony has been immersed are represented in the historical growth band record. Looking back in time, and matching bands with historical climatic events (i.e. El Niño, bleaching, rain events/coastal runoff or ocean acidification), reveals how adaptable or resilient the coral colony was to a changing marine environment.  By collecting samples from a variety of reef ecosystems across the PIPA, as well as across the globe, WHOI scientists are constructing a large dataset to help us better understand what factors influence coral growth.

A growing number of coral cores are stored carefully on the right, for later analysis back at Woods Hole. On the left, Chip sets up water chemistry instruments for reef deployment. (Photo: Sangeeta Mangubhai)

Corals are one of many components making up a reef ecosystem. And no two coral reefs look the same, even at the same island. So, figuring out what a coral reef ecosystem “should” look like takes time and effort. Onboard the Hanse Explorer, our team of biologists and oceanographers are piecing together the parts of the puzzle for this region of the ocean and fine tuning the definition of a healthy reef ecosystem. Researchers are inventorying coral, invertebrate, reef fish, and shark populations, while others are making measurements for water chemistry and collecting biological genetic information. The goal of this collaborative effort in the PIPA is to identify similarities and differences in geographically-similar reef ecosystems, where each ecosystem is far from being directly comparable.

Yashika Nand enjoying a school of jacks as they swim past the reef (Photo: Sangeeta Mangubhai)

Of course similar species live on the reefs within the PIPA, but each reef has its own signature, its own communities of fish and coral. There is not a blueprint for how a healthy coral reef ecosystem “should” look, but there are commonalities in how a healthy reef ecosystem looks. The whole story has yet to be written and the work completed during this research expedition will identify commonalities and differences found in many of the physical, biological, and chemical factors influencing reef health within the PIPA, the greater equatorial Pacific, and across the globe.

Charles (Chip) Young, PhD, is an Oceanographer with NOAA's Coral Reef Ecosystem Division cooperative institute, the Joint Institute for Marine and Atmospheric Research at the University of Hawaii. With NOAA he participates in coral reef ecology research and monitoring projects across the Pacific Ocean, investigating thermal stress and ocean acidification topics. Chip and the Coral Reef Ecosystem Division have been collaborating with Dr. Anne Cohen at Woods Hole Oceanographic Institution since 2010, primarily focused on coral growth and bioerosion rates. For the PIPA 2015 research expedition he'll be participating with the dive team from Woods Hole Oceanographic Institution, studying ocean chemistry, species specific coral growth rates, net reef calcification rates, and variability in benthic community composition.

Aquarium researchers and staff are on expedition to the remote Phoenix Islands Protected Area (PIPA) to study the natural history of the islands, surrounding reefs and connecting open water ecosystems. Research on the 2015 expedition will directly inform the management and maintenance of this world-renowned MPA. Today's post comes from the expedition's chief scientist in the field Sangeeta Mangubhai.

A challenging first day at Orona Atoll – heavy rainfall, strong winds, ocean swell, a skiff needing repairs and then a warning about a tsunami moving across the Pacific Ocean and destined to reach us at 3 a.m. tomorrow morning. It is also 17 days into our expedition and the team is starting to feel a little fatigued. Everyone is encouraged to take days off if they need it to re-energise, but scientists are a stubborn focused lot. We recognize that each day out here is precious. A day resting means one less day of data.

Our dives at Orona Atoll were very different from others. Our first dive was on the windward side, and we jumped into a spectacular healthy, diverse coral community at a site called ‘Aerials.’ Free of bleaching and with little disease, the corals were thriving and densely packed together. We also saw a couple of black tip sharks early in our dive, and the water was abuzz with fish. The highlight for the fish team was seeing bumphead parrotfish, which have remained elusive on the other islands.

Photo by S. Harper

Our second dive was characterized by a very bare reef, with little living coral community. During our early expeditions, we hypothesized that nutrients may have been leaching from the lagoon onto the reefs causing poor conditions for corals. However, a decade later we know this is not the case, and the likely cause is from an old ship wreck that has been on that reef since 1936. We are starting to build up evidence in the Pacific of ship wrecks causing mass mortality of corals, and leaving behind what is called a ‘black reef.’ Peter Gawne and I have been collecting water samples, and in collaboration with Jessica Carilli and Randi Rotjan, we will be doing experiments towards the end of the trip to assess whether iron from these ship wrecks are leaching out and causing these extensive black reefs to form.

Coral bleaching of Hydnophora rigida off Orona (Photo by S. Mangubhai)

Our last dive was on the leeward side was characterized by large areas of coral bleaching. The bleaching was mainly in a branching species called Hydnophora rigida which carpeted large areas of the reef. This means that the warm pool of water that is sitting over the central Pacific extends as far as Orona, and this thermal stress is causing corals to start bleaching. We have seen early signs of coral bleaching at each of the six islands we have surveyed to date. At each island, it is almost the same species that are first to bleach. [See pictures of bleached corals from Kanton Island.]

Over the next three days Yashika Nand and I will have a chance to conduct extensive surveys all around the island, weather permitting. We have just come back in from deeper water where we spent the night, waiting for the tsunami to dissipate by the time it reaches us in the Phoenix Islands. All dives are now back on, as we are safe and unaffected. Back to the blue!

— Sangeeta

Aquarium researchers and staff are on expedition to the remote Phoenix Islands Protected Area (PIPA) to study the natural history of the islands, surrounding reefs and connecting open water ecosystems. Research on the 2015 expedition will directly inform the management and maintenance of this world-renowned MPA. Today's post comes from the expedition's WHOI researchers Hanny Rivera and Liz Drenkard.

You have likely heard of corals, corals reefs, and all the wonderful life they host underwater. However, I am often greeted with surprise when I say that corals are actually animals, not plants, or rocks, though in a certain sense all three of those descriptions apply. Indeed corals are animals, in fact they are in the same Phylum (broad category) as jellyfish and anemones, but they also create rock as their skeleton, and they have tiny algae (photosynthesizing marine plants) that live inside their tissue. So in a way they are animals, rocks and plants all combined into one fascinating creature.

When you look at a huge coral colony, only the outer layer, a thin veneer of translucent tissue, is actually alive. The rest is the calcium carbonate skeleton that the coral has secreted over the course of years, possibly decades or even centuries. While the skeleton can tell us about the ocean's history, we can learn a lot about the coral's present health by studying the living tissue.

Side view of coral showing tissue thickness, the living (brown-ish) portion on the top, and the skeleton (white) below.

During our fieldwork in PIPA we have taken small samples of coral tissue to study the animal's "vital signs" much like a doctor might take a blood sample or a biopsy from a human patient, but our tests are quite different.:

Liz Drenkard sampling a coral colony

Symbionts
Most reef-building corals have algal symbionts living in their tissue, which we analyze to learn about the coral's nutritional status/health. These small, single-cell plants provide the coral with food and in return, the coral gives the algae a safe place to live. These symbionts (commonly called zooxanthellae) are what give the coral its coloration.

When corals are stressed, they tend to lose their symbionts. This process is referred to as bleaching because the coral's white skeleton can be seen through the translucent, symbiont-free tissue. If the symbionts are not recovered in a short period of time the corals may die due to starvation.

MIT-WHOI Graduate student Tom DeCarlo inspects a bleached coral in Palau. (Photo by Pat Lohmann, Woods Hole Oceanographic Institution)

The number of algal cells in the corals tissue and the amount of photosynthetic pigment (chlorophyll) within these cells tells us how much "food" the coral could potentially be getting from its symbionts. Corals can also change the kind of symbiont that is living in their tissue during a bleaching event. Some symbionts are more tolerant of high temperatures than others.

Bleaching often occurs when water temperatures get hotter than normal. This year, El Niño has been warming the water of the central Pacific. We have seen considerable bleaching in various corals species in the Phoenix Islands. Having the opportunity to be on site during such an event in a very remote area is very exciting for us, as we can see first hand how corals are responding on a short- term basis, for instance, by symbiont shuffling (swapping the kinds of symbiont that are dominant).

Lipids
From our biopsies we can also measure how far the tissue layer extends into the corals skeleton (i.e. its "thickness") and how much lipid, or fat, that tissue contains. The amount of lipid in the tissue indicates how much energy the coral has stored up, which may help the coral survive thermal stress events. For example, if the coral undergoes severe bleaching, and can is no longer receiving its normal food intake from its symbionts, it can tap into those stored energy reserves to survive, much the way think how bears eat a lot before winter and then live off use up those reserves during hibernation.

Sangeeta Mangubhai and Peter Gawne examining bleached corals at Kanton Island (Photo credit: C. Cook)

Under bleaching conditions, the coral may need to rely heavily on its energetic reserves in order to survive until they can recover its symbionts. By measuring tissue thickness and lipid content, we get an idea of the corals' nutritional status and its ability to withstand stress. We can also look at various isotopes (variant of an element with a different molecular weight) in the tissue to assess where the coral may have gotten that carbon source from, if nutritional supply may have originated—from algal photosynthesis or direct feeding.

Genetics
Lastly, taking tissue samples allows us to study corals using genetic techniques. We extract DNA from the tissue, look at specific markers in that DNA and create a map of how corals from different islands are related to each other (a field called population genetics). With these methods we can understand if one island hosts an isolated population, such that future coral juveniles will be dependent on healthy adult corals on that site, or if an island gets a steady influx of juveniles from other islands, such that even if the native population suffers (say from a bleaching event) the coral population can be expected to recover in the long term due to incoming juveniles from other healthy nearby reefs. This analysis is very important for understanding how reefs in different areas will fare under changing ocean conditions.

Corals are vital for healthy coastal ecosystems, and while they face a multitude of threats both environmental and anthropogenic, we have hope that they will be resilient enough to survive and continue and provide habitat for fish, thousands of invertebrates, give our coastal cities protection from storm surge and erosion, as well as remain the thriving ecosystems they have been so that future generations may also go scuba diving and snorkeling on vibrant colorful reefs.

Liz Drenkard, PhD studies the response of ocean dynamics, ocean biogeochemistry and living marine resources to CO2-induced climate change with implications for conservation. She is currently a postdoctoral researcher at Rutgers University working with Dr. Enrique Curchitser and the Environmental Systems Modeling group to use high resolution ocean models to understand reef ecosystem vulnerabilities or resilience to climate variability. During this expedition, she will be collecting temperature and current profile information to validate the model we will use to study the connectivity between PIPA and other Pacific reef corals. Her graduate research, which focused on the role of nutrition
in coral calcification response to acidification and the implications for reefs in the equatorial Pacific, was conducted at WHOI under the mentorship of Drs. Anne Cohen, Dan McCorkle and Kris Karnauskas. Her outreach efforts include serving as a science liaison for the National Network for Ocean and Climate Change Interpretation; In the past, she worked as an assistant aquarist at the New England Aquarium and is currently a volunteer for The Raptor Trust: a wild avian rehabilitation center in NJ.

Hanny Rivera developed a deep passion for the ocean early on, having grown up in Miami, snorkeling and exploring the Florida reefs. As an undergrad she studied Organismic and Evolutionary Biology at Harvard University and completed her senior thesis on coral reproduction and recruitment in Bermuda. Hannyis a current member of the Cohen Lab at Woods Hole Oceanographic Institution as part of her Ph.D. in the MIT/WHOI Joint Program in Biological Oceanography. She is most interested in studying climate change impacts on coral reef ecosystems and understanding how corals may be able tolerate environmental stressors such as ocean warming and acidification. When she is not scuba diving, she enjoys salsa dancing and painting.