Thursday, April 14, 2011

Heron Island, Part 2: April 3-6


It is kind of strange to have lecture at 7:30 a.m. on a Sunday morning, but every moment on Heron Island is a learning opportunity.  After we got through a few more lectures, we had lunch, and then grabbed snorkel gear and headed out onto the reef.  Our first snorkel trip was into the harbor.  Visibility was bad, and my mask kept filling up with water.  I didn’t see that many animals, but other people apparently saw a lionfish and a few sharks.  We were all wearing these full-body blue stinger suits – they are a tight, thin, stretchy material (which jelly stings can't penetrate), with mittens and stirrups and a hood.  We kind of looked like those people who perform actions for special effects movie people to create CGI characters off of later.  Aka, we looked very dorky, but were safe.



Our second trip was to Shark Bay.  It didn’t live up to its name; I saw no sharks.  The visibility was much better, although my mask still filled up with water, so I had to stop to empty it every few feet.  We saw so many interesting creatures around the coral structures!  My favorite was a HUGE snail – its shell was at least 2 feet long.  Baby Great Pink Sea Snail, perhaps?  Snorkeling was a lot easier than I had thought it would be, but I am still very glad I took 6 months of intensive swim classes before coming here.  I didn’t need the advanced swimming skills so much as the not-panicking skills and the treading water skills.  The wind and the waves made our second snorkel trip a little intense.  I was very glad for the stinger suit, as three different little jellies floated right past me – purple, brown, and clear.  Another group saw a Portuguese Man of War.

We were assigned our research project groups.  I worked on something called the Halo Effect relating to meiofauna, which I will describe in more detail later.

Sunday morning, we rescued 2 baby sea turtles from the birds (seagulls and noddy terns), and put them in the touch tank – they were later transferred to a bucket.  We had to keep them until dusk, or else they would have been immediately been picked off by predators once they entered the water.

 The touch tank is really neat - it has living corals (soft, branching, etc.; no fire coral!), sea cucumbers, a royal blue sea star, a beautiful clam, and many other creatures.


On Monday, the majority of the group left to go SCUBA diving.  The few of us that were left went for a snorkel with Ian, in the hopes of seeing some sharks and rays.  I picked out a new snorkel at the dive shop, which had a much better seal.

Monday evening, my group began our research project by getting in the ocean and tagging + measuring 6 coral bommie sites.  A bommie is basically a lone outcrop of coral (picture a large rock in the ocean, but made out of coral, with other bommies scattered nearby).  We are studying meiofauna distribution around these bommies, to figure out if there is a halo effect of grazing (the hypothesis is that meiofauna closer to the bommie get eaten earlier in the day, so you would see meiofauna concentrations that make concentric rings around the bommie in their distribution).  You can see a halo effect with algae grazing, so it seems as though there would be one with meiofauna as well.  The term "meiofauna" is simply a size category; think of the creatures I studied as plankton that live in the sand.  This research project is an area of study that is new to science.

Tuesday, we started our research in earnest.  Our snorkeling crew of the day was in the water three times, morning, afternoon, and evening.  We decided to make the mid-day sampling period just for observations, and not bringing back more sediment.  (This mid-day observation was eventually scrapped altogether, due to time constraints.)  The sediment sampling is very tedious and takes an incredibly long time.  We had to identify and count meiofauna – small organisms – so my plankton identification skills came in handy.  There were a lot of copepods, nematodes, polychaetes, ostracods, and flatworms.  One sample had over 500 copepods and worms combined!

Preparing to do research

Tuesday afternoon, the entire group went snorkeling with Ian.  We walked out to these pools on the very edge of the reef.  We had to be careful to not get washed over the side of the pool into the ocean, but it wasn't that much of a challenge.  Overall, it was an amazing experience - the best snorkeling of the entire trip.  The light hit the water just right, so the reef and all the fish were brilliantly illuminated, like those National Geographic pictures you see of the Great Barrier Reef.  There were SO many fish!  Damsels, parrotfish, wrasses, you name it.  Schools and schools of them, hanging out in and around the coral.  We saw a couple of boxfish, and a giant lobster, but the highlight was a group of about 20 squid of varying sizes.  They are very graceful in the water, and are amazing to watch.

Note: there were small, blue Portuguese man of wars all over the beaches!  Good thing we had our stinger suits on.

1 comment:

  1. Re: First picture: HOTNESS!!!

    Re: Clam: That's a bright blue, how/why does it get that color?

    What color do the different jellies mean?

    ReplyDelete