In a previous post we discussed evidence of human influence on the terrestrial side of Orona: ancient Polynesian villages, a more recent (2001) settlement project that was rather short-lived. But there is underwater evidence as well. For example, abandoned anchors off of old ships lying undisturbed amidst the corals.

Anchor left on the reef

But there are also lingering global influences that are evidenced by what is NOT present on the reef. For example, lack of live coral. These mostly dead and overgrown coral skeletons are remnants from previous bleaching events, the most severe of which occurred in 2002-2003.

A lone shark swims over a reef of encrusted coral skeletons

All is not lost, however. As was found on the 2009 expedition, the reef was seen to be rapidly recovering from bleaching, thanks in part to reef herbivores that were keeping the dead substrate clean and ready for coral recolonization. Thanks to these coral reef "lawnmowers", the reef is mostly free from the weedy macroalgal species that are competitively dominant. Instead, the reef harbors mostly Halimeda (a green calcareous algae) and CCA (crustose coralline algae, in pink), which do not impede the resettlement of corals.

Reef herbivores (Acanthurids) graze turf and macroalgae off the reef

And the fish just keep on coming.... even in the depths

...And in the shallows

The presence of such high abundance and diversity of fishes is likely a key part of reef recovery. Part of the beauty of PIPA is that all of the island-surrounding reefs are part of the no-take portion of the MPA, which means no fishing. No fishing AT ALL. Hopefully, such conservation measures will enable these reefs to recover from the global impacts of climate change, and we will continue to document and observe the changes in these reef communities over time. 

Photographer Keith Ellenbogen, a regular Aquarium blog contributor, is on the expedition. Here are some of his images from Nikumaroro Island.

A deserted island beach may look idyllic, but imagine being stranded here... quite a different perspective! TIGHAR thinks Amelia Earhart and Fred Noonan may have have been stranded on this island... they are soon headed to PIPA, and perhaps we'll find out.

One of the popular "Amelia" theories is that her plane landed on the reef flats during low tide (the TIGHAR hypothesis). You can see here how the reef flats may have been suitable for an emergency runway!

This crab has a story to tell, and the punchline: "Stay away from my territory!"

Birds landing on the Nai'a have a good view of the exposed  SS Norwich City shipwreck, to the left.

Stormy sunsets are one of the amazing views in PIPA

But nothing beats a full rainbow. :-)

Photographer Keith Ellenbogen, a regular Aquarium blog contributor, is on the expedition capturing stunning underwater photos. These images are from dives near Nikumaroro Island.


Now that you've seen Nikumaroro from the air, it's time to dive down and see the reefs below.

Colorful green Halimeda algae and pink crustose coralline algae covering a mound of dead coral substrate (Photo: K. Ellenbogen)

Atop the large plates of mounding Porites corals is the perfect place for an underwater cleaning station. This grouper is actually being cleaned by a tiny wrasse (see the blue and black striped fish to the right?). (Photo: K. Ellenbogen)

The silvery surface waters of Nikumaroro are home are far from empty...Scomberoides lysan(queenfish) and Elagatis bipinnulata(rainbow runner) abound! (Fish ID by Dr. Les Kaufman) (Photo: K. Ellenbogen)

A school of herbivorous convict tangs feeding on turf algae (Photo: K. Ellenbogen)

A scrubby coral forest regrows in the shallows (Photo: K. Ellenbogen)

Herbivory in action! (Photo: K. Ellenbogen)

Photographer Keith Ellenbogen, a regular Aquarium blog contributor, is on the expedition capturing stunning underwater photos of marine life as well as these aerial images of Nikumaroro Island that were made using a kite.


Flight and Nikumaroro are no strangers to each other. Indeed, Nikumaroro is perhaps most famous as a potential landing site for Amelia Earhart, the famous female aviator. The Amelia Earhart recovery is being attempted by TIGHAR, The International Group for Historic Aircraft Recovery, who made the movie below (posted for convenience, and also shows a helicopter flyover of the island):



But when our team is on Nikumaroro, they are busy gathering biological information about the corals, fishes, and seawater chemistry (similar to their work on the other islands, detailed in previous posts). Amidst all the hard work, a bit of fun is definitely welcome! One of the goals was to collect water samples from the Niku lagoon - these kite photos helped to verify the shallow nature of the lagoon, and provided a fun way to contextualize the site of sampling. In this case, Keith and Jay mounted a GoPro camera to a kite in order to get a birds-eye view of the island, without taking on Amelia-style risk. :-) We are happy to report that there are no missing aviators as a result of this activity. Instead, just some great photos! Not bad for a team that primarily works underwater. Enjoy!

Expedition members Keith and Jo test the aerodynamics of the kite and camera. (Photo: S. Mangubhai)

Expedition Leader Sangeeta launches the kite, which is being controlled by Keith. (Photo: K. Ellenbogen)

Aerial photograph of Nikumaroro Lagoon from the kite (Photo: K. Ellenbogen)

Aerial photograph of Nikumaroro Lagoon from the kite (Photo: K. Ellenbogen)

This post is by Expedition Team Member Jennifer Boulay.

The idea for this blog hit me during one of our dives and I wrote this down on my slate. So here it is literally from the reefs of Phoenix Island to you. I am a PhD student at Penn State studying coral genetics and my work here is like being on a television crime drama.

Okay not exactly.

In reality, my work is much cooler. Instead of a dirty crime scene, I get to be here on the beautiful reefs of the Phoenix Islands and instead of taking samples from a dead body, I take small samples of coral tissue under the water.

Jennifer Boulay collecting sample of porites (Photo: K. Ellenbogen)

But back in the lab, I do get to use information in DNA to solve a mystery: How far do PIPA corals move within and among PIPA islands and the other Pacific archipelagos?

I know it can be difficult to think of a coral as a motile animal because they look like rocks or plants but like some plants they do have a motile life phase. In order for you to understand the ecology behind coral genetics, I think need to explain about reproduction in corals (Don’t worry I promise I will keep it PG). Coral colonies reproduce in two ways:

1) A coral colony can release sperm, eggs, or sometimes both into the water and mate with other colonies of the same species. This is how corals sexually reproduce. The resulting larvae can travel in the water on currents to other reefs or stay locally and settle back on the same reef. For these sexually produced colonies, their genetic signatures allow us to model patterns of connection among reefs. This will tell us if the colonies were locally produced or if coral larvae from one island make it to other islands within PIPA or even the other islands of the Pacific. My lab has been working on reef connectivity across the entire Pacific in one species of coral. In fact, the first samples I ever analyzed during my PhD were sent to my lab by Randi Rotjan from Enderbury on the PIPA expedition in 2009. So the Phoenix Islands are especially close to my heart and I am so excited to be here and experience them with my own eyes. But this year, I am collecting samples from all the islands and will be able to look at connectivity within PIPA in addition to the connections among the PIPA islands and other Pacific Islands.

2) Another way a new coral can establish on the reef is from an existing colony. A piece or branch of a coral colony can break off and become a new colony. This is known as asexual reproduction by fragmentation. Think of your garden at home. Even though corals are animals they reproduce somewhat like plants. You can take a cutting of a tree, plant it in the ground, and it will grow into a new tree. But this new tree is a genetic clone of the original plant from which you took a cutting. These two plants will share the exact same DNA. In my lab at Penn State I will use 11 sites in the DNA to give each coral a unique identifier, its genotype. If two samples have the same genotype those colonies are clones of each other. For branching colonies it is easier to understand how a branch can break off in a storm for example and become a new colony but many of the corals on the reef just look like rocks or even grow encrusting on the surface. For these colonies it is possible that fish bite the coral, not to eat it but to get at other things living inside the corals like mussels or worms. The coral pieces that are broken off might establish their own colonies nearby. The 2012 PIPA expedition is the optimal way to study this unique method of asexual propagation because we have scientists collecting data on fish assemblage and corals at the same time.

A tissue sample of Porites for genetic analysis. (Photo: K. Ellenbogen)

 
Unlike in TV, my results are not completed in one, neat, 30-minute episode, so STAY TUNED.

-Jennifer

Orona Island is relatively lush, hosting many prominent coconut palms, scrub brush and other trees. The expedition team went ashore to assess infrastructure that was previously installed by the Kirabati government in 2001. The idea was to host a small fishing settlement, but the project was unsuccessful, likely due to the extreme isolation and resulting issues (freshwater availability, supply runs, etc). Though the infrastructure is relatively new (only a decade old!), you can see the impact of the intense sun and salt spray. Interestingly, Orona also hosts prehistoric Polynesian ruins ... but those are on the other side of the island and were not visited by the team. That's the thing about the Phoenix Islands - tiny specks in the Pacific, but yet there's always more to see.

Orona Island (Photo: K. Ellenbogen)

A Maneeba (local word for village hall) (Photo: K. Ellenbogen)

On Orona Island in the Central Pacific a safe remains locked within the bank.  A place to withdraw money... but there's no treasure left. (Photo: K. Ellenbogen)

Tuake Teema explores and assesses the conditions of the island and village that was last inhabited in 2001. (Photo: K. Ellenbogen)

The remnants of  a church bell from 2001. This bell was rung every Sunday.  (Photo: K. Ellenbogen)

A korean or japanese-style fishing helmet with a light that washed ashore in Orona Island. There is lots of shoreline debris littering the islands (read more here).

Our lab studies the effect of climate change on coral reefs. The major threats to coral reefs that are associated with a changing climate are twofold. The first is the warming of the oceans. The increase in carbon dioxide in the atmosphere is warming the earth through the greenhouse effect. This increase in temperature also occurs in the oceans, and we have observed measurable warming of the oceans in the past few decades. Higher temperatures are devastating to corals because they can lead to the breakdown of the delicate symbiosis between the coral animal and its photosynthetic algae that allows corals to grow. When corals are stressed at higher temperatures, they expel their algae. Because the algae give the coral their color (the coral tissue itself is clear), the loss of algae causes the underlying white skeleton to become visible. Thus, this process is termed coral bleaching. Coral bleaching very often leads to the death of corals, and the cascading effects of coral mortality that occur through tropical ecosystems can ultimately devastate entire reef systems.

Dr. David Obura measures a new table coral growing amidst fields of dead coral at Kanton Island in the Phoenix Islands during the 2009 PIPA Expedition (Photo: Brian Skerry).

The second major threat to coral reefs is the acidification of surface oceans. In addition to warming the ocean, the increase of carbon dioxide and other greenhouse gases in the atmosphere leads to the increased dissolution of carbon dioxide in the oceans. Due to the complex chemistry of ocean water, this ultimately leads to a decrease in pH. This process, called ocean acidification, is a threat to corals because the drop in pH makes it difficult for corals to build their skeletons. In fact, corals are usually unable to produce any skeleton at all in extremely acidified conditions. As a result, ocean acidification threatens the ability of corals to build the structures that support a multitude of other reef organisms in the future.
These threats to coral reefs have intensified in recent years, especially as temperatures have increased. There have been a number of severe coral bleaching events in the past few years. Most notably, scientists observed up to 100% coral mortality worldwide in 1998 and again in 2010 when ocean temperatures became very warm in associated with strong El Nino events.

Expedition team members Pat and Jay prepare to take a core sample of a coral. (Photo: K. Ellenbogen)

We also know that many of the corals in the Phoenix Islands bleached in 2002, and that many of the reefs in this island system experienced considerable coral mortality during this time. Ten years later, we are interested in examining how well the corals are recovering from this (and other) stress. To do so, we are using information that has been stored within the coral skeleton. As corals grow, they lay down a calcium carbonate skeleton in alternating bands of high and low density. Like the rings of trees, these bands are an annual record of coral growth, as the distance between bands signifies how much a coral grew in a particular year. We can use this information to determine how fast a coral was growing each year, whether the coral was stressed during a particular period of time, and whether the growth rate of the coral is increasing or decreasing over time. Because the Phoenix Islands are largely uninhabited, the historical growth patterns preserved in coral skeletons are perhaps the only record we have for how the corals around these islands have been growing for the past few decades.

Expedition team members Pat and Jay using the pneumatic drill to collect a core sample. (Photo: K. Ellenbogen)

As you might imagine, obtaining these skeletal records is no easy feat. We access the coral growth record by collecting cores from the coral skeleton. Our team uses two types of drills to obtain cores: pneumatic and hydraulic drills. The pneumatic (powered by air) drills are smaller, hand-held drills can collect cores 3 cm in diameter and up to 45 cm long. The hydraulic (powered by vegetable oil) drill is considerably larger, requiring two people to operate and producing cores that are 8 cm in diameter up to 6 m long.

Expedition team members Pat and Jay hold a carefully collected coral core sample. (Photo: K. Ellenbogen)

Unfortunately, the growth bands are not visible to the naked eye, so scientists have to be creative to see them! Our lab has turned to medical technology to visualize the coral banding pattern. Upon our return to our lab at Woods Hole Oceanographic Institution, we will scan the cores we have collected in a CT-scanner – the same way doctors examine their patients! These scans allow us to visualize the bands in the cores, and we can use these images of the cores and their bands to calculate coral growth rates. The particular coral species that we are studying grows about 1-2cm per year, and so a 3m long record could trace coral growth for up to the past 300 years! We can examine the growth record of multiple corals to understand the general trends in coral growth on these reefs.

-Hannah and Kathryn

 
Corals are animals that build a calcarous skeleton and harbor plant-like photosynthetic symbionts within their tissue. This fabulous trio of animal-mineral-vegetable often looks like a rock, a pillar, or a table formation... but it you look up close, you will be able to see the beautiful textures, patterns, and colors that are formed.

During the daytime, polyps are retracted (you can see the white-ish tentacles hiding in the grooves). The protruding ridges are the hard coral skeletonc overed by a think layer of coral tissue, sheltering the polyp mouths in the grooves/valleys.

Corals are in the class Anthozoa, which literally translates to "flower animal". Though the polyps are again retracted here, you can begin to see why: the floral-like patterns of this coral (Hydnophora rigida), and imagine what it will look like with polyps extending to feed with their anemone-like tentacles. 

The green centers here are bursting with GFP (green fluorescent protein), which is very commonly observed in corals. These green areas are where the polyps will extend at night - if you look closely, you can see the small mouths of retracted polyps. 

Crustose coralline algae (CCA) is a beautiful, pink, cement-like algae that provides important substrate for coral growth. You can see the coral (on the right) slowly overgrowing the CCA on the left. The growth margins of the coral are light whitish/brown because the skeletal color is not yet overtaken by the color of symbiont-laden tissue... coral symbionts provide much of the brown-ish color displayed by corals. 

Fungids are fabulous! As you can tell from the photos above, there is a wide variety of coral patterns and structures. Fungids (like the one shown here) have layered ridges, often sporting only one (or sometimes a few) polyps amidst all that structure. Looking almost like sand-dunes from above, there is actual remarkable detail in the ridge structure that distinguishes one species from another. 

This is blog entry posted from the field during the 2012 Phoenix Islands Marine Protected Area (PIPA) Expedition. The Phoenix Islands are an isolated island chain more than 1,000 miles southwest of Hawaii. They are part of the island nation of Kiribati, which partnered with the New England Aquarium and Conservation International to create PIPA in 2008. Today it is one of the world's largest marine protected areas and a UNESCO world heritage site. This voyage is part of a regular series of scientific expeditions to investigate coral health and study ecosystems and biodiversity.

Photographer Keith Ellenbogen, regular Aquarium blog contributor, is on the expedition capturing stunning underwater photos of marine life as well as the essence of life on a working research vessel.  

Have you ever wondered how these blogs are arriving to you from the middle of the Central Pacific? We showed you some of the early prep in this post, but it's quite a different experience "dancing" with a satellite dish on a moving boat, amidst the dives, the data crunching, the sample preparation, and the gear maintenance. Here's how it's done...

Ketih and Sangeeta are in the wheelhouse, setting up the blog...


While on the deck just outside, the daily dance commences. The dancing partner? The air waves of modern communication in one of the most remote parts of the world! :-)





The goal: to get the magic 3 satellites to align and the signal strength to stay steady...

Of note, we are not near any land or cities that could be identified by the machine... which greatly confuses the machine. Luckily, it (usually) manages to work anyway.

With a compass, the sun, the stars (and oh fine, a GPS...) as our guide, we sail from island to island with only satellite communications to connect us to the outside world.