Showing posts with label plankton. Show all posts
Showing posts with label plankton. Show all posts

Tuesday, May 26, 2015

Belize 2015 | When We're Not Diving

Staff from the New England Aquarium recently traveled to Belize as part of a long-term research program by Aquarium scientist Randi Rotjan, PhD, to monitor coral health near Carrie Bow Cay. Today's post comes from educator Sam Herman.
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Even though we aim for four dives a day, we can't be in the water all the time. On past trips they have done some hermit crab research, but that's not happening this time. So, how do we fill the dry time?

Firstly, I've spent A LOT of time studying. There are a lot of coral species to learn and keep straight in my head. But, after a few days I think I'm finally there! It must have helped having a gorgeous place to read the coral book.

Sam's favorite study spot.

One thing that happens pretty regularly are lab tours. Visiting groups of students and tourists will stop by Carrie Bow Cay to see the lab spaces (and the world famous outhouses). Since Scott and Zach have the most experience here they tend to lead these tours, but I've been tagging along and helping out as much as I can. 

Scott showing students around the lab.

An additional task I wanted to accomplish while here was check in on some of my favorite organisms...plankton! We get a huge variety of plankton in Boston Harbor and I love sharing those with visitors. (If you like plankton, definitely check out the Aquarium this summer. We'll have some plankton set up most of the day on the third floor!) I was curious what the plankton might look like In Belize. Turns out it's pretty similar. Using a plankton tow I caught a bunch of zoea (a stage of the crustacean larval cycle), some larval fish and a worm I have so far been unable to identify. It's fairly comparable to samples I've collected in Boston, albeit at a lower density than our cold northern waters. Nice reminder that it's just one big ocean and there are similarities all over. 

The photos on the left are a zoea and a fish larva from Carrie Bow Cay,
and on the right are similar examples from Boston Harbor. 

We also help other researchers complete their tasks as needed. However, the most important things we do outside of diving are eating and sleeping, so we can get ready to do more surveys! 

Speaking of which...until next time!
-Sam-

Friday, May 9, 2014

Bahamas: Night Diving

Aquarium staff recently returned from an expedition to the Bahamas. They've been sharing pictures and stories from their time exploring the turquoise blue waters of Caribbean—complete with pictures, video, conservation notes and a taste of life on board a working boat. 

This final post from the series about a night dive comes to us from Austin, who normally cares for the shorebirds on Central Wharf.

On March 28, we completed the last dives of the trip. We did an evening dive and then a night dive at the wreck of the Sapona, which is a concrete-hulled cargo steamer that ran aground during a hurricane in 1926, and before then was used as storage for supplies of rum and whisky during Prohibition. The Sapona is always a favorite dive spot on our collecting trips.

Interior of the Sapona wreck



My favorite aspect of this dive site was the amazing invertebrates. On the night dive we saw many impressively large sea urchins and sea cucumbers. The hull of the ship was covered in corals and basket stars that are curled up and inconspicuous during the day but unfurl their branching arms at night to capture plankton. The most beautiful coral we observed on the wreck was Tubastrea, commonly called sun coral. This coral has huge yellow-orange polyps which open up at night in order to feed. You can see a fiberglass replica of this coral in the Giant Ocean Tank that looks just like the real animal.

Unfurled Tubastrea with a large urchin seen during night dive 
We also saw this awesome redeye sponge crab climbing on a column in the interior of the wreck. Sponge crabs wear a “cap” of living sponge as camouflage. They cut and shape the sponge and hold it in place with their rear legs. Sponge crabs usually hide under their sponge during the day, so this night dive was a great opportunity to check out this crustacean when it was active.



You will probably notice many white particles in the water in these clips. These particles are living plankton of all sorts that was attracted to the light from our flashlights. We scooped up some of this plankton from the water surface while we on the boat to take a closer look. We saw a fantastic diversity of tiny animals – shrimp, fast-swimming polychaete worms, amphipods and larval fishes. If you look carefully you might be able to spot a larval crab and a tiny pipefish!



The Sapona night dive was a really amazing experience and a great finale to our collecting dives.