“To move, to breathe, to fly, to float, to gain all while you give, to roam the roads of lands remote. To travel is to live.”
– Hans Christian Andersen
I couldn’t be happier here. This island is truly remarkable and the experiences I am gaining are invaluable. Both on land and in the sea, I couldn’t feel more fortunate to be living this life and having this opportunity to travel the world. 🙂
So I’ve been diving every day the past three weeks collecting cages for two more experiments that have now ended for the summer. It’s definitely been a lot of work every day. I can’t remember the last time I slept in or didn’t feel tired! But somehow in the instant I splash into the water I became spellbound by the sea around me. In that moment, everything else seems insignificant.
Underwater, it’s nearly impossible to tell from which direction you hear a noise. That’s because sound travels four times faster in water than in air. When you’re on land, sound waves travel through the air and the vibrations hit your ears at slightly different times, hence your brain’s ability to distinguish where the noise originated. Underwater, sound travels far too quickly for your ears to tell from which direction the noise came from. So whether you hear a tank bang, a roaring engine, or whales bellowing songs to one another, there’s no way to tell where the sound is coming from other than to just look around and hope you see something. I’ve been hearing humpback whales singing while diving on the fore reef and it’s always so amazing! Every time I start hearing them sing their deep, bellowing songs to one another, I am desperate to see where the sound is coming from.
Ah I’ve just been so fortunate here. I’ve seen humpback whales at the surface and once I even caught a glimpse of a juvenile underwater! It was a brief moment, but I could faintly see the outline of a white underbelly, massive pectoral fin, and undeniable tail fluke glide in and then out of my field of vision within seconds. Then, on our last trip out to the fore reef, we saw a mother and her calf nursing at the surface. The baby’s little pectoral fin (relative to mom’s) would come out of the water as he’d roll over and play alongside his mother. It was a great way to start the beautiful day.
So there’s a lot of work we’ve been doing underwater the last couple weeks. One of the experiments we brought in to harvest was the hysteresis experiment I was describing earlier. This experiment was designed to test how fish grazing intensity (measured by cage hole sizes) affects and/or alters established algal populations and also examines how it may control and/or limit algal growth. Each of the cages contained two tiles initially planted with Turbinaria, that very hardy algae I mentioned before, which is only grazed on by a select number of adult fish. Adult Turbinaria are too difficult for other fish to eat due to its calcified structure and the fact that it doesn’t actually contain many nutrients (smart on the algae’s part – don’t be tasty and nothing wants to eat you). The other two tiles in each cage were left open in order to see if other kinds of algae would grow and if or how grazer intensity would affect them. So each of the cages was brought in and the tiles were scraped. All Turbinaria were counted and measured and all other algae on the tiles were weighed, dried, weighed, muffled, and what do you know, weighed again! This took a couple days of diving to retrieve the cages and then another couple days in the lab to do all the processing. Following the harvest of that experiment, the very next day we were back out in the field bringing in the next algae experiment. This experiment was implemented three years ago in July 2010 and consists of multiple cages with varying grazing intensity treatments in order to test for algae settlement over time. For this experiment, we only had to harvest the July 2010 tile, although some had all four tiles on them from different time periods. Once we brought in the cages, the tiles were removed and new, clean tiles took their place. The cages were then redeployed the next day. So it became our weekly cycle – remove some cages, re-deploy the previous day’s cages, lab processing in the afternoon, dinner, sleep, wake up, and then back in the field!
Whether you’re a principal investigator (PI), post-doc, graduate student, or even undergrad, you get one short field season at a time to attempt to answer all of the questions you want to tackle. While the PI’s get the opportunity to keep coming back, many of the graduate students only get a couple of opportunities for this kind of fieldwork. So when you’re here, you are living and breathing your work. For most of the graduate students, their days don’t end at 5pm. It goes into the night and on to the next day. Whatever it takes to get the data they need for their thesis! So some parts of the summer consist of that mad dash for grad students to deploy experiments, collect samples, or whatever else needs to get done before they go.
Over the course of the summer, people have filtered into Gump Station and people have filtered out. It’s been amazing to meet all these different people, but always sad to see them leave after you’ve gotten to know them so well. Right now we’re down to all the UCSB PI’s, grad students, undies (aka – undergraduates), and a couple others from different universities. The numbers seem to be dwindling, but I’m hopeful that I’ll be seeing many of these faces again as we all continue into our careers and into the international realm of marine science.
Okay there’s still more! So after the harvest of these two experiments, we then moved on to conducting the MCR long term surveys around the island on fish, coral adults, coral recruits, and invertebrates. That’s what we’ve been doing this past week. I was assigned the invertebrate survey and so I’ve been counting and measuring all the invertebrate species I find within each 5×5 meter plots at all six LTER sites. It’s been amazing to travel around the island with my advisors Russ, Andy, and Sally performing these surveys alongside them. It’s been my favorite part of the summer. I love that I’m able to assist them in their research and on top of that I’ve been able to see the whole island and dive in the beautiful fore reef that surrounds it!
Here is an image of a 5×5 meter plot that we survey. Most of the sites have five plots, although there’s a site with ten and another site with twenty. Russ and Sally, my advisors, perform the coral recruit and coral adult counts. The coral reefs here in Moorea suffered substantial losses after undergoing a crown of thorns outbreak beginning in 2008 followed by Cyclone Oli in 2010 that further decimated the reef. Fortunately, the coral reefs along the north shore of Moorea (where our twenty plot site is) have been recovering wonderfully! There are lots of small corals such as Pocillopora spp., Acropora spp., and a couple others that have become seemingly abundant along the reef. While this makes for fantastic news for a coral reef ecologist, it also makes for a lot more work counting all the new babies!
This is my other advisor, Andy, who conducts the fish surveys for the LTER island surveys. It’s hard to tell by the images so you’ll just have to trust me when I say there are A LOT of fish on the fore reef. I actually have no idea how he can count and keep track of the hundreds of fish that cruise by, swim, and dart around the plots, but he identifies and counts them all! Also, in the bottom image you can see a lemon shark cruise by as we were doing our survey.
So here is my datasheet and the very fancy tools I use to conduct the survey! My task is to identify, count, and measure all macro-invertebrates I encounter on each plot. However, the majority of inverts I see on the fore reef are various species of urchins and the occasional hermit crabs, cone snails, and even sea stars.
I also see the occasional Turbo marmoratus, a huge marine gastropod (snail)! These guys are really beautiful! The white calcified structure you see in the right image is the operculum of the snail. Operculum is Latin for “lid,” and this structure is used to by the snail like a trap door in order to “close up” and hide its body from predators. When it’s feeding, the actual soft body of the snail is exposed. Once disturbed, such as when I pick it up to see if there’s a snail inside, it rapidly pulls its body back into the shell and the operculum tightly seals the creature inside. Ingenious!
Being in the water so much has made the time fly by here. It’s hard for me to believe that it’s already the end of August and that this summer experience is rapidly coming to an end. One more week of Moorea, and then I will be onto the next amazing adventure in Rangiroa and New Zealand.
Thinking about family and friends every day and wishing you could all be here with me.
Manuia (cheers) for all the good times to follow!