10/29/09

PHOENIX ISLANDS ADVENTURES - November 2!

Want to hear more about the Phoenix Islands? Want to meet some of the expedition members in person? Want to meet some of the students who corresponded with the team on this very blog? Want to see new (never before seen!) photos?

Join us THIS COMING MONDAY, November 2, at 7pm. The lecture is free; and free snacks will be provided as well!

Please register (free!) using this link - seats are limited!


Phoenix Islands Residents (photos: J. Stringer)

Rising From the Ashes: The Phoenix Islands Protected Area
These days it is impossible to find an ecosystem that is untouched by man. Human effects are felt from the polar ice caps to the deep sea, and coral reefs are far from the exception. The major stressors on most reefs--sewage inputs, overfishing, point-source pollution and extensive tourism--are local. However, a few remote places still exist where reefs are not affected by these local stressors; humans only affect these reefs on a global level. The Phoenix Islands are among these treasures. Their remote location, coupled with their intensive regulations and protection, create a unique opportunity for scientists to study a reef free from local impact.

New England Aquarium researchers recently participated in a rare expedition to the Phoenix Islands. In this lecture they will share scientific findings as well as anecdotes from this remarkable adventure.


Stuart, David, Les, and Randi underwater, measuring reef creatures like the clowfish and anemones featured here (photos: J. Stringer)

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10/24/09

One Fish, Two Fish, Red Fish, Blue Fish

The Phoenix Islands "Greatest Hits" highlights continue with this guest post by Stuart Sandin.

#8: Measuring the diversity, abundance, and biomass of PIPA fishes

Although corals and some algae form the backbone of a coral reef, it is the fish that give reefs their personality (at least from the perspective of a 'fish guy'). Notice, for example, that movie writers and animators did not have us finding Porites corals, but instead we focused on the reef fish Nemo and his friend Dori. Without fish, a reef would be essentially static, with limited color and even more limited movement.


(Photos: R. Rotjan)

We fish guys make a living out of looking for fish, counting how many are around, and trying to figure out what they do. This all begins with advice from Dr. Seuss, "One fish, two fish, red fish, blue fish." During our time in the Phoenix Islands, Les, Tuake, and I tried to gain some ecological perspective regarding the fish from each of the islands. In set areas, we counted every fish swimming around, identifying the species and estimating each fish's size. From this we can estimate some fundamental properties of the fish assemblage -- how many fish are around, how much do they all weigh (which is important because fish vary dramatically in size), and what are the ecological roles that these animals are filling?



(Photos: R. Rotjan)
Now what did we find? Well, we were able to confirm the long-pondered concept -- if you don't fish in an area, you get more fish. The reefs of the Phoenix Islands have no fishing activity, so it is not surprising that we find more fish there than in more heavily fished areas like Fiji, Hawaii, or any other inhabited island. But what is surprising is the sheer bounty of fish that were present on the reefs. It seems that during every dive we would come across a large school of some species; sometimes we saw dozens of giant trevally, or hundreds of parrotfish, or thousands of convict surgeonfish. Add up all of these fish and you have a particularly large assemblage of animal mass. The best insights into this is perhaps completed by comparing the fish assemblages from the Phoenix islands to more commonly visited areas. Let's use the metric of total fish biomass (in other words, imagine that you took every fish out of a section of reef and weighed them...this is our metric of choice when summarizing multi-specific fish assemblages). Our surveys of the Phoenix islands revealed that there were about 250 grams per meter squared of reef, or about a half pound of fish in the area of the hood of a car. In contrast, the reefs of the main Hawaiian islands, Fiji, and Jamaica have about 65, 30, and 20 grams per meter squared, respectively. The reefs that most people visit during vacation are a shadow of their historic potential.

(Photos: R. Rotjan)

But the reef fish of the Phoenix islands were not wholly pristine and devoid of the scars of human activities. On a number of the islands we did not see many reef sharks, and when we did find them the animals were small and young. Although fishing is currently outlawed from all reefs within PIPA, this has only been true for the past few years. Within the past 10 years there has been some fishing activity on the reefs, particularly targeting the sharks for their fins. Catering to a lucrative market for shark fins (used in shark fin soup), foreign fishing vessels find it to be profitable to legally (and sometimes illegally) to visit even the most remote reef areas to harvest sharks. The regulations of PIPA prohibit any future shark finning from the reefs of the Phoenix islands, and the good number of juvenile reef sharks that we saw during this trip suggests that a recovery of shark populations is possible. But in order to realize this regrowth of shark populations, we have to assure compliance with the regulations. Multi-national efforts to improve surveillance of the remote and protected areas of the Pacific (under the jurisdictions of Kiribati as well as French Polynesia, the United States, and other nations) are beginning and will be essential to protect the splendor of these last remaining gems in sea.

The theme of 'Phoenix rising' has been common during this trip -- we saw evidence of the corals recovering from a massive bleaching event, we saw bird populations soaring following removal of introduced rats, and we also see evidence that even the insulted shark populations can recover to full glory. I am proud to have been a part of such a proactive team of conservationists, politicians, and scientists focused on protecting the Phoenix islands. Only due to this type of effort can I hope that we will protect, and perhaps even improve, vast regions of the ocean for our children and their children to marvel at into the future.

-Stuart-

10/23/09

The Snappers in our Grouper

The Phoenix Islands "Greatest Hits" highlights continue...

#7: Photography and videography on a scientific expedition

We were fortunate to have several excellent professional and amateur photographers and videographers with us on this trip. You've heard directly from Brian Skerry, the award-winning National Geographic Magazine (NGM) photographer with us (see Brian's earlier posts here). But we also had Jeff Wildermuth with us, assisting Brian and making professional videos for the New England Aquarium and Conservation International.


Jeff Wildermuth, in action (Photo: R. Rotjan)

Jim Stringer is an excellent amateur photographer who has provided many of the photos posted on this site. In addition, Rob Barell and Sam Campbell (NAI'A) shot terrific, high-def video footage of the science-in-action, the reef denizens, and anything else in sight. Craig Cook was not only our MD; he is also an accomplished photographer and helped to capture the essence of our trip, as well as helped Les Kaufman take some scientific footage of coral fluorescence. It's quite likely that hundreds of thousands of photos were taken--I'm not a real photographer (neither pro nor high quality amateur), but I took over 3,000 shots! Add that to the impressive skills of Kate, Larry, Les, David, Greg, Stuart, Tuake, Tukabu, and Alan... and you get the idea. This trip was well documented by all of these photographers (snappers) on our trip (in our group-er). My apologies for the bad puns.



Our snappers, in action - L. Madin, S. Campbell, J. Stringer. (Photos: R. Rotjan)

So, speaking of snapper, what was the most photographed fish? My guess is the charismatic and in-your-face red snapper (Lutjanus bohar); they were everywhere! As for coral, my money is on Porites lobata (a lovely mounding coral present at most sites). David Obura might be the most photographed human; he is especially photogenic with a clipboard and transect tape in hand. Fairy terns might be the most photographed bird. But in truth - I have no idea. Even 2 weeks later, we're still compiling our photographs and sharing files. However, many of our images will be published in Aquarium publications, and shown on November 2 (lecture details here), so keep your eyes open. :-) You never know when you might recognize a Phoenix Islands photograph premiered here on this blog.


Snapper with snappers! (Photo: R. Rotjan)


Before this trip, I had no idea what it was like for Brian and Jeff, our professionals, to photograph a story in the field. I'll re-post some comments of Brian's here, since he says it best:

"Photographically, the challenges have been substantial. Even when all is perfect on these central pacific reefs, making great images can be difficult because fish are skittish and hard to get near. The nature of being on an expedition means we also move continually in order to collect scientific data, so each dive is in a new location. Without the chance to dive the same sites repeatedly and gain knowledge about subtle nuances, I must simply spend as much time in the water as possible and hope to find something especially interesting happening."


Brian and Jeff with gear on the boat; Brian contemplating unpacking the photo gear (Photos: R. Rotjan)

"For this assignment, I have 11 days to photograph underwater, quite a bit less than the 10-12 weeks I typically have for an NGM assignment. Still, I hope that the handful of key images I've produced so far and others I hope to make in the few days remaining will speak to the important story and illustrate the issues we are experiencing here I the central Pacific Ocean."
Brian is being modest--he may have only a handful of images that meet his extremely high standards, but we were all wowed at our first glimpse of his photos. He captures movement, texture, and energy that really demonstrates the wildness of the Phoenix Islands Protected Area.

It was terrifying having the pro's photograph us, however! During our "Phoenix Islands Firsts" post, Tuake described what it felt like to be under the lights:

"I was a bit nervous to be photographed by the National Geographic People! I was finding it hard to breathe on my tank when Brian was taking pictures of me. Normally, I like to be underwater for the fun of diving. I felt relieved when Brian was telling me that he was done with me. I hoped that I had done what I was supposed to do as part of my Phoenix Islands mission. I count myself fortunate to be attached and learning from highly academic scientists who are on this marine expedition. This was indeed a first for me--to be photographed for a magazine story."


Multiple snappers - count 'em, three! (Photo: R. Rotjan)

As for me, I managed to avoid the camera most of the time and be a "snapper" in my own right.... taking photos for science and pleasure with no remorse (thank goodness for digital photography and large memory cards!). But if this post has you hoping for more information on the *real* snappers and groupers of the trip - and yes, I do mean the fish - stay tuned! Stuart and Les will be guest-blogging soon on the fishes hits of the trip. :-)

-Randi-


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10/20/09

Put the Lime in the Coconut

The Phoenix Islands "Greatest Hits" highlights continue...

#6: Medical objectives and triumphs of the 2009 PIPA expedition

Some of the most incredible highlights from the trip were the things that never happened. These things are of huge concern when headed 5.5 days away from anywhere, and when engaging in high-risk activities such as repeatedly diving in shark-filled waters with sharp corals at every turn. Of course, there are always the other regular afflictions--sun poisoning, broken bones, infected wounds, parasites, disease and who knows what else. So, you can see that it is quite worth mentioning that no major medical maladies occurred on our expedition. Hoorah!


Dr. Craig Cook on SCUBA with camera in hand and no sharp coral in sight (Photo: R. Rotjan)

Despite our good fortunes, we weren't willing to risk our lives on luck alone. Instead, we placed our lives into the care of the NAI'A, and into the very capable and experienced hands of Dr. Craig Cook, who was our expedition medical doctor. Craig is no stranger to practicing medicine in high-risk, remote locations. He is the Medical Editor for Sport Diver Magazine and a referral physician for Divers Alert Network. With a background in Anesthesiology, Dr. Cook has been a consultant to the National Oceanographic Atmospheric Administration (NOAA), and is also a scuba instructor and has been actively diving for 40 years. It is with his guidance and wisdom that we hauled a Hyperlite Hyperbaric Chamber with us all the way to middle of nowhere.


Dr. Craig Cook (black shirt) demonstrating the hyperbaric chamber to expedition members (photos: R. Rotjan)

What exactly is a hyperbaric chamber? It's used to treat decompression sickness, (aka "the bends"), which can occur when diving. Basically, divers are at pressure (every 30 feet of depth is equivalent to approximately 1 atmosphere of pressure). The air we breathe is a mix of gasses, including oxygen (~21%) and nitrogen (~78%). At depth, air is compressed (more or less depending on the diving depth), but "the bends" occurs upon depressurization. As divers return to the surface, gas expands as the pressure decreases, and air (basically a mix of dissolved gasses) can form bubbles. Bubbles are usually small and eventually dissipate, but sometimes a bubble forms that is too large, or unfortunately located, and can cause illness ranging from mild to extreme severity. Its effects may vary from joint pain and rash to paralysis and death. To treat the formation of bubbles, doctors use a hyperbaric chamber to recompress a patient (simulate diving depths) while on oxygen, to re-dissolve the bubbles and hopefully prevent their reformation.


Close-up views of the chamber and pressure valves (photos: R. Rotjan)

Luckily, we never needed to use the chamber, and Craig spent most of his doctoring time trying to ease our seasickness, or treating bruises, cuts, scrapes, and allergies. Beyond that, we were all healthy and returned home safely and intact. We were prepared for much worse, however. Craig made sure that each diver was equipped with communications technology (in case we got lost or separated), a safety sausage (again to increase our visibility in case we got lost), a flashlight, a knife (to free from entanglements), a whistle (to call for help), and a tourniquet (in case of shark attacks). However, the one thing that we were all most scared of was a coconut incident. After all, there were a lot of coconut palms on some of the islands!


Coconut palms on Nikamororo (photo: R. Rotjan)

You see, one of my favorite marine biology statistics is as follows: you are more likely to get hit on the head by a coconut than to suffer a shark attack. True, or urban legend? Who knows, but to quote a 2001 journal in the ANZ Journal of Surgery entitled Coconut palm-related injuries in the pacific islands "A total of 3.4% of all injuries presenting to the [Solomon Islands] surgical department was related to the coconut palm. Eighty-five patients fell from the coconut palm, 16 patients had a coconut fruit fall on them, three patients had a coconut palm fall on them and one patient kicked a coconut palm".


"Dangerous" coconut palms 0n the Phoenix Islands (photos: R. Rotjan)

In other words - beware of falling coconuts, but if one falls, mix it with lime (full of vitamin C, it prevents scurvy!), and yell "DOCTOR!" loudly. Thanks to Craig, tropical fruit-borne fractures, scurvy, and the bends were not an issue... and we're most grateful.

Dive safe,

Randi


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10/16/09

Breathe Deep

The Phoenix Islands "Greatest Hits" highlights continue...

#5: ROV exploration of PIPA depths

Take a deep breath. Go on, try it. In with the good air; out with the bad air. Ahhhhh. It's easy, and feels good, eh? Now, try it underwater. With SCUBA, you can only breathe so deep - around 120 feet on air, if you're a conventional diver. At best, might be able to breathe about 300 feet deep. What about on a submarine? Okay--you can breathe deep there, but you're breathing recycled air. And hence the topic of today's post: since we can't breathe deep underwater (at least not easily), how do we explore deep underwater?


(Left Photo: David Obura) (Right Photo: Jim Stringer)

The answer to this question depends on how deep you want to go. The coral reefs on PIPA are a reef formation known as an atoll (described in an earlier post). One of the features of these mid-ocean, volcanic atolls is that they are basically seamounts that break the surface--so they descend very deep, with a very steep slope. Kiribati is also full of seamounts that do not break the surface. In fact, Kiribati is home to ~4% of the world's seamounts. That's a lot of ocean to explore below the surface!


Seamounts featured between McKean, Rawaka (Phoenix) and Enderbury Islands (Photo: Google Earth)

It would be great to get a manned submersible out to PIPA someday, and hopefully we will soon. But as a first glimpse of the deep, we brought an unmanned ROV with us on this expedition. This ROV (Remotely Operated Vehicle) can only go 500 feet deep, but that's 380 feet deeper than we were diving. And yes--you guessed it--since the ROV was unmanned, breathing was not an issue. :)


Mo preparing to launch the ROV off the boat for a dive (Photo: Larry Madin)

Now, I'm not a stranger to the concept of deep depths. I used to work on deep-sea hydrothermal vents (miles below the ocean!) , but I've never personally journeyed there (though my experiments have). So naturally, I was extremely curious to be on-site for some deep-sea exploration. One of the big advantages of working on these reef atolls with their steep, sloping sides is that we could (and did) literally dangle the ROV out of our ship window (see Mo above with the ROV). Greg could (and did) sit at our dinner table on-ship and drop the ROV below us, while others of us were diving on the reef. As any deep-sea scientist will tell you: what an unlikely (and pleasurable) way to explore! Greg posted extensively on this earlier - see Greg's posts for more photos and details.


Randi Rotjan, David Obura and Les Kaufman look on as Greg Stone controls the ROV (Photo: Larry Madin)

A first glimpse was just enough to leave us breathless (figuratively, of course). Corals living past 300 feet! The crystal clear waters of PIPA were able to allow enough sunlight at depth to support the coral-algal symbiosis. We saw lots of healthy corals, though the diversity was low (just a few species) And fish! Snapper (the same we'd been seeing shallow), and more baby sharks patrolling the slopes. In fact, on one ROV dive, 10 sharks (gray reef and black tip) were seen. And here's the enticing part--when we looked further down the slope at the end of our ROV's tether, we could see that there was more life, still. Breathtaking.


(Photos: Jim Stringer)

Marine organisms are not limited to the shallows the way that humans are. Sadly for us, we have to make the choice between deep breaths or deep depths; we generally can't have both. But ROV's and manned submersibles give us borrowed lungs and enable us to explore the last unexplored frontier--the ocean floor. After all, we know more about the moon that we do about our ocean floor! I'm excited about future ROV and sub explorations of PIPA. After all, the thrilling and mysterious sights of the deep sea will take your breath away--but thanks to this technology, not literally.

-Randi-

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10/14/09

Christmas Tree Worms

Note: Students from Celeste Young's biology class (Monument Mountain Regional High School; Great Barrington, MA) posted a question for Aquarium researcher Dr. Randi Rotjan in the comments section of this post. Here is Susanna's question with Randi's answer in light blue:

Hello! This is Celeste Young & her biology class! What is the scale of the christmas tree worm picture?

Hi Celeste and Susanna,

Thanks so much for reading the blogs, and for posting your question!

Christmas tree worms are small-- the crowns are only a few centimeters across, at most. They are hard to measure, since they actually retract their plumes (or branchial crowns) into their tubes with the slightest disturbance in the water. Tubes are made of calcium carbonate. These worms settle on the surface of a coral (they do not bore into the skeleton) and grow at roughly the same pace as the coral tissue - thus, they grow really slowly! Some worms are known to be up to 40 years old, so they also can live a very long time. Worms feed by filtering plankton from the water column with their branchial crowns. They retract into their tubes to avoid predators (and rulers). The best way to add a ruler to the photo is to place the ruler down, let the worm retract, and then re-emerge. However, this only works in very calm water, with high flow, the ruler will not stay in place! :-)

Check out the photos below of an exposed worm (left); and then the same worm retracted into its tube (right). These photos were taken by a student of mine, Sarah Abboud, who is actually studying these worms for her masters thesis. These photos are taken from Moorea, French Polynesia, but are of the same species of worm that we observed in the Phoenix Islands.


Spirobranchus giganteus christmas tree worm - exposed and retracted. (Photos: S. Abboud)

Below is another worm next to a piece of flagging for scale. The flagging is 2.5 cm across, so you can now estimate the size of the worm crown!


Spirobranchus giganteus christmas tree worm - exposed 
Here are some additional photos by Sarah, measuring the diameter of the tube. Tube diameter correlates to worm age, but not to crown size. Crown size varies with depth; worms in deep areas with high water flow (surge) actually have shorter crowns so that they don't bend or break when water is rushing past them. Deep areas with low surge have taller crowns. Here are some scale bars next to worm tubes; the left photo has an exposed worm behind the 1 cm scale bar (it's orange).


Spirobranchus giganteus christmas tree worms - retracted. (Photos: S. Abboud)

Finally, here's a worm retracted, but just barely: you can see it's crown folded within the tube, and just breaking the surface.


Spirobranchus giganteus christmas tree worm - retracted. (Photos: S. Abboud)

The photos on The Slow and the Spineless post were not taken for an explicit scientific purpose, thus, there are no scale bars on those photos. But I hope that this gives you an idea of scale, nonetheless.

Thanks again for your question!

Best fishes,

-Randi

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10/13/09

The Slow and the Spineless

The Phoenix Islands "Greatest Hits" highlights continue...

#4: PHOENIX ISLANDS REEF INVERTEBRATES

The invertebrates of this trip deserve to be in the top 10; but on this blog thus far, they've barely received an honorable mention. Mea culpa! Because of the scientific interests of the expedition members, invertebrate diversity attention has been taxonomically-eclipsed by the coral invertebrates, the remarkable fishes, and the algae. But, invertebrate diversity is important and interesting, and I'm not the only blogger who thinks so! Check your backbone at the door and go visit Chris Mah's Echinoblog, as well as The Other 95% (written by Kevin Zelnio and Eric Heupel) if you like inverts. Full disclosure: I do not know all of the taxonomic identifications of the critters posted here, so I invite you to join me in this adventure (semi wiki-style)! If you post the ID in the comments section below, I will amend the blog to include the correct ID and give you credit for the match. :-)

Without further ado, allow me to introduce a few of the "the slow and spineless" Phoenix Islands critters. Most of these images will enlarge when you click on them.


The Christmas Tree worm is aptly named for it's shape (photo above by David Obura). They also come in all sizes and colors (see shots below).


Spirobranchus giganteus on Porites lobata corals (photo: R. Rotjan)

Time for a little echinoderm shout-out (for more, check out Chris Mah's blog here). You may not realize it, but echinoderms are a whole lot more than just sea stars! But, we'll start with a Linckia spp. on the left (not sure which one, any guesses? Also, anyone notice anything a little unusual about this Linckia? Count the arms...). But, sea cucumbers (holothurians) are also echinoderms (photo on the right). New England Aquarium Researcher Tim Werner works on these. I think this one is an Actinopyga spp., and Tim Werner has confirmed that it is A. mauritiana. Thanks, Tim!

 
Linckia spp. sea star and holothurian sea cucumber (photos: R. Rotjan)


Phoenix Island Sea Urchins (photo: R. Rotjan)

Above are two more echinoderms - a Diadema spp. and an Echinometra spp. sea urchins; I think! Let's go check out some more inverts. There are two focal invertebrates in the photo below. The one to the left is an echinoderm (a Culcita novaguinae seastar). But take a look at the invert on the right-- definitely NOT an echinoderm.


Culcita novaguinae cushion star(left) and Tridacna spp. clam (right) (Photo: R. Rotjan)

The photo below shows a bunch of molluscs (Tridacna spp. clams nestled amidst the coral). The photo above shows a clam also - on the right side, next to the cushion star. Chris says that all of these clams are Tridacna maxima. Thanks, Chris!


Tridacna spp. clams (Photo: R. Rotjan)

Molluscs are great; they include clams, mussels, snails, octopus, and squid. They also include nudibranchs, which are shell-less snails like the one below. I think this nudibranch is a Phyllidia spp.; any other ideas?


Nudibranch (Photo: R. Rotjan)Below is another confusing photo. There is no mollusc in the photograph (only a crustacean), but the crustacean is using a snail shell. Yup, it's a land hermit crab (Coenobita perlatus).


Coenobita perlatus hermit crab (photo: R. Rotjan)

Hermit crabs are very interesting creatures, and they are very picky about their shell choice. While we're on the topic of crustaceans (e.g. shrimp, lobsters, crabs), check out this terrestrial land crab (often called a sally lightfoot). Eric Heupel suggests that it might be Graspus tenuicrustatus.


Sally lightfoot crab (Photo: R. Rotjan)

Back to my favorite group--the cnidaria (e.g. corals, jellyfish, anemones). Below are some beautiful hydrozoans. These animals have the appearance of a feather, but the branches have polyps (just like corals).


Hydroids (Photos: R. Rotjan)

Of course, corals will always have my heart. Hard corals, scleractinians, have been featured on many posts here already, and are the main focus of our reef recovery attention. The reason why? Well, hard corals may be slow and technically spineless, but they are the backbone of coral reefs. They have calcium carbonate skeletons that create the complex reef structure. In an earlier post, we showed you lots of dead coral skeleton covered by crustose coralline algae. That skeleton is made by the coral animal via a symbiosis with a photosynthetic algae and provides shelter for most of the other organisms on the reef. To see more about the symbiosis, check out the Blue Impact Tour and click on "color changing corals".

 
Acropora table coral closeup and colony 

But the main point here is that coral animals and their calcium carbonate skeletons create the complex structure of reefs.

So spineless? Hardly. These inverts are themselves the backbone of coral reefs. No bones about it.

-Randi-

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