Tag Archives: Hydrozoa

Still itchy

The tropical rainforest and coral reef are similar in that they both survive on very nutrient-poor soil and ocean water respectively. This is because there’s very rapid nutrient cycling in the leaf litter of the rainforest and the mangroves near coral reefs.

I also noticed a lot of interesting interactions between species in these environments outside of simple predation. In the rainforest, there were organisms like ticks (which surprisingly don’t bother me anymore) that act as parasites and the Azteca ants that live symbiotically in Cecropia trees. And in the coral reefs, there were organisms like Christmas tree worms that extend deep inside the corals and stay there for life and clownfish that live symbiotically in anemones.

It’s hard to remember what I expected from the course after I already experienced it, but I guess that’s why we wrote our pre-departure blogs. In mine, I wrote that I was “anticipating a fascinating (but incredibly busy) two weeks.” I’d say this was pretty accurate to the trip, except it was even more fascinating and busy than I imagined.

One thing I certainly didn’t anticipate was our incredible experience at the ATM cave, which was most definitely my favorite part. I had no idea tourists were allowed to cave like that (i.e. swimming through small spaces and even scaling a small wall at one point). My least favorite part was probably running through the Mangroves of Death on our first day at the reef. The amount of mosquitoes there is unbelievable, and I was pretty impressed when three other students volunteered to go there for our marine debris collection.

One thing that I learned that I won’t forget is the Mayan history that we heard about. I was fascinated by the elaborate rituals performed by the priests. Another thing is that the only way to kill a tick is to sever its head from the rest of its body (which you can use your fingernails to do). The third thing that I learned and won’t be forgetting is to avoid fire coral!

Rainforest species seen: Homaeotarsus pallipes, Enema endymion, Pyrophorus noctilucus, Euchroma gigantea, Calopteron discrepans, Hegemona lineata, Eburia pedestris

Reef species seen: Millepora alcicornis, Millepora complanate, Millepora squarrosa, Kirchenpaueria halecioides, Dentitheca dendritica, Cassiopeia xamachana, Aurelia aurita

Escaping the Sandflies

May 28, 2019

Today was full of travel. We woke up bright and early at 4:45 am to begin our three hour boat ride back to the mainland. The ride was smoother this time because we were traveling with the current (see Keegan and Brendan enjoying the boat ride below). And we saw two dolphins as we were approaching the shore!

Once we made it to the airport, we had some free time to buy gifts and souvenirs, so I of course bought some Marie Sharp’s hot sauce for the hot sauce lovers in my family.

The flight went by pretty quickly, and it was so good to see my pets (three cats and one dog) when I finally got home even if it meant I had to walk the dog and clean the litterboxes before passing out in bed.

Lionfish Guts

May 27, 2019

Today, we cleaned up marine debris on the island. Part of the experiment was looking at the amount and composition of trash in different areas of the island, so three brave souls (Kaela, Amy, and Kelsey) volunteered to cover the Mangroves of Death.

After going through the collected marine debris, Scott brought out some coconuts, and we got to try fresh coconut water and coconut meat.

In the afternoon, we dissected the lionfish that Scott and Herbie speared a couple days ago. This involved estimating sex and reproductive maturity of the fish and then identifying its different organs. When Liz and I opened the stomach of our lionfish, we found a whole undigested fish in it! We identified it as a juvenile slippery dick.

Passenger Fish

May 26, 2019

Today we started and completed a whole new experiment. To look at sea urchin community structure (and the indications it may have for herbivory and reef health), we went out and collected sea urchins in a bucket and recorded the species and diameter of each urchin.

During the search, I noticed several new hydroids! I saw what I believe to be a lot of Box Fire Coral (Millipore squarrosa), which is the third and last species of fire coral that I found to be common in the Caribbean.

I also spotted some Kirchenpaueria halecioides, a small hydroid that gets up to about one inch tall (see photo below) in addition to a possible Feather Bush Hydroid (Dentitheca dendritica).

Much later in the day, we got back in the water for a night snorkel. It was fun, but my dive light went out, and we were all way too close to each other – I think we were all paranoid about losing the group. When I got back, I found a tiny little fish inside my swimsuit. It must have somehow made its way into my skintight dive skin and swimsuit, but nothing can surprise me at this point.

Stuck on Comb Jellies

May 25, 2019

Today was a big day for Scyphozoa and Ctenophores, otherwise known as true jellyfish and comb jellies respectively. When we unloaded at one of our experiment locations, we had to quickly get back into the boat when we realized Moon Jellies (Aurelia aurita) were everywhere (they can deliver a painful sting), but that doesn’t mean I didn’t take a picture first.

There were also a lot of comb jellies (unknown species). These jellies look similar to jellyfish but are actually from a completely different phylum and use sticky cells called colloblasts to catch prey rather than stinging cells like jellyfish. This is why Amanda was able to safely hold one in her hand.

Eventually, our marine safety officer Herbie found a reef that wasn’t infested with jellyfish. While he was checking the area, he said he saw lots of squid and lionfish. I didn’t end up finding any squid myself, but I did get to watch Herbie spear one of the lionfish – they’re invasive to the Caribbean and eat a lot of important herbivorous fish populations.

Later, we went to the forereef, which was much deeper than the patch reefs inside the atoll. I got to see some living elkhorn coral (Acropora palmata), a nurse shark, several southern sting rays, and a very linear group of small squid.

Critter Collection

May 24, 2019

Today, we spent the morning collecting data in two coral reef locations. Liz and I used a similar underwater language today to communicate. We were recording points with live coral or sediment, so cupping our hand into a “c” meant live coral and crossing our index and middle fingers meant sediment.

Exploring the reef after our data collection was incredible. I spotted many fire coral, mostly branching fire coral (Millepora alcicornis) but also some blade fire coral (Millipore complanate).

Later, we returned to the sea to scour an area of seagrass for critters that we could bring in to examine more closely – no hydrozoans or jellyfish were found, but we did gather some other amazing finds, including an octopus, two fire worms, a West Indian sea egg urchin, a sun anemone, and many more. My favorite are the conchs because they’re shells are beautiful, and they have strange little eyes on long eyestalks.

Anna Is My Hero

May 23, 2019

I am currently writing this blog with a small but distinct yellow dot in my vision. This is because I’ve been staring at the light in our cabin for a while, out of necessity of course.

About thirty minutes ago, Kelsey pointed at our light and asked what all the little bugs around it were (there were a lot). We suspected they were sandflies, so Anna, the bravest of us, stepped on a table and used Kaela’s notebook to swat as many as she could. It was confirmed that they were sandflies when Kaela’s notebook revealed about a hundred small smears of blood. I followed Anna’s swatting with lots of clapping around the light to attempt to get the sandflies that weren’t collected on the ceiling. What a day.

Earlier today, we did an experiment involving seagrass and algae competition. It soon became clear that any reef experiment requires strong communication between researchers, so Liz (my buddy) and I developed an underwater language in which the letter “a” in sign language meant algae and using both hands to form the written letter “s” meant seagrass.

No hydrozoa, schyphozoa, cubozoa, or ctenophores spotted today because much of our time in the water was spent collecting data in the seagrass. Hopefully, I’ll spot some tomorrow.

I Am Utterly Exhausted

May 22, 2019

Today was a doozy. We had a three hour boat ride to Glover’s Reef this morning. It was a small motor boat speeding across three hours worth of ocean, so it was more like a three hour rollercoaster.

Once we made it to Glover’s, we immediately had a tour of the island, then lunch, and then our first snorkel. We couldn’t stay out for long because the current was strong, but Liz and I made it out to the patch reef, which was beautiful. I’m so excited to go out there again.

Closer to shore, we spotted many upside-down jellyfish (Cassiopeia xamachana) – a scyphozoan from my taxon ID card!!! These jellyfish are particularly interesting because they often rest on the ocean floor upside down with their tentacles in the air such that they look like harmless plants.

We went out again later to a different area of the reef. This area was much more shallow, which made it harder to navigate. This wasn’t ideal because there were many fire coral. I noticed both branching fire coral (Millipore alcicornis) and blade fire coral (Millipore complanate). These hydrozoans are actually not coral at all and can cause a nasty sting with their nematocysts.