Water Quality

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From the Field: Playa Veracruz

Tuesday, January 29th, 2013

by Katrina Lohan

Veracruz Beach on the Pacific side of Panama at low tide. (Kristina Hill)

In search of more Striostrea sp., Kristy and I, with our collaborator from the Smithsonian Tropical Research Institute, Mark Torchin, traveled to the beach at Veracruz at low tide. As we have been typically finding this species of oyster submerged in small ponds or attached to rocks in the intertidal, we were prepared to sample fast to beat the incoming tide.

To get to the right habitat, we had to carry all our gear about a mile from the beach, across a sand spit to the rocks that are exposed at low tide. Unfortunately for us, the sampling did not go particularly quickly. While these oysters tend to be large, they were also covered in mud and algae, making it difficult to distinguish between the rocks and the oysters. With each oyster that I was able to hammer off, the tide was slowly pushing me back into the rocks. Finally, Mark warned us that we should start heading back as we didn’t want the tide to trap us on these rocks by covering the sand spit before we had crossed it.

I quickly took a sample of the surface water, in the hopes that I can compare the parasites found in the surrounding water to the parasites found in the oysters. Then we started to head back, picking up a few more oysters along the way. As these oysters are big, they are also heavy! So our journey back to the beach was much slower than our journey out to the rocks. Thankfully we returned safely to the car, with all our gear and oysters, and headed back to the lab to process them.

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From the Field: A Warm Welcome in Bique

Monday, January 28th, 2013

by Kristina Hill

The mangrove-lined path down to Bique beach.
(Kristina Hill)

The first thing on our to-do list for our Panama Part II adventure was to head to Playa Bique on the Pacific Coast of Panama to find more Striostrea sp. and Saccostrea palmula oysters. In order to get to Bique, we had to travel down an unpaved, rocky clay road that wended through lush green vegetation with white cows grazing on hillsides. The beautiful scenery distracted me enough that I didn’t feel my head hit the roof of the truck with every single bump in the road, and distracted Katrina enough that she was able to keep her breakfast!

We arrived at Bique to find a small village with brightly colored houses and friendly people. There were also several dogs in the village anxious to welcome us–as we unpacked our gear, one decided to mark his territory right on the side of our bucket! (Is there an old saying about a dog urinating on a bucket bringing scientists good luck? If not, there should be.) Then we tromped down a sandy, mangrove-lined path to the rocky intertidal, where we were able to find the oysters we were looking for.

The Striostrea species we found were large and seemed to like the tidal pools found in the rock formations at low tide. They were large oysters (we were finding 80-100 mm ones), and it looked like people were “harvesting” the meat and leaving the shells behind—it was very difficult to pry the oysters from the rocks without shucking them open. The Saccostrea palmula oysters we found were much smaller (20-60 mm), so they probably aren’t consumed from this location.

We headed back to the lab, cleaned our bucket and set straight to processing the oysters for metazoan and protistan parasite analyses.

Here’s to hoping the rest of our collections go as well!

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From the Field: Regresamos a Panamá!

Monday, January 28th, 2013

by Katrina Lohan

Beach at Punta Culebra, on the Pacific side of the Panama Canal. (Katrina Lohan)

Our first trip to Panama felt like a whirlwind! We learned a lot about what worked and what didn’t for processing all the oysters we collected. We also learned that identifying oysters just by looking at them is really hard. To prepare for this trip, Kristy, Greg and I went to the Smithsonian’s Natural History Museum to meet with our collaborator, Ellen Strong, who is the curator of all of the bivalves. She showed us the oyster collection, and the three of us spent a few hours examining the shells of the different oysters. I’m really glad we did, because we all left feeling much more confident in our ability to identify oysters in the field and in the lab–something that will be very useful!

Our current trip to Panama is expected to be three and a half weeks long, and we have an ambitious schedule. The first few days will be spent finishing our collections on the Pacific side of the Panama Canal, then onto the Smithsonian’s Marine Station at Bocas del Toro for a week and half, and then back to the Naos Laboratory to finish sampling the Atlantic side of the Panama Canal. It’s time to put those oyster identifying skills to the test!

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From the Field: Farewell, Panama

Friday, December 28th, 2012

by Kristy Hill

The oyster Isognomon sp. in the crevices of a rocky reef at Fort Sherman on the Atlantic coast of Panama. (Kristy Hill)

Yesterday we ventured to the Caribbean coast of Panama, where we had beautiful weather for sampling. Our first stop was near Fort Sherman, a former United States Army base, where we found lots of Isognomon oysters on the subtidal rocks. These oysters are unusual because instead of cementing their shell to a hard surface, they attach themselves to rocks and mangroves with a threadlike structure. We also were able to collect a Crassostrea sp. and a few Ostrea sp. as well.

We then headed to the Smithsonian Tropical Research Institute (STRI) Marine Laboratory in Galeta. We braved the somewhat turbulent waters and snorkeled to collect from the mangroves, despite reports of crocodiles that frequent the area. Oh, the lengths we’ll go to in the name of science.

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From the Field: Punta Chame–Oysters Galore

Thursday, December 27th, 2012

by Katrina Lohan

Katrina Lohan and Kristina Hill sample oysters off the rocks near Punta Chame, on the Pacific side of Panama. (Carmen Schloeder)

Some sampling sites are glamorous. Others are not. Our site near Punta Chame was literally off the side of the road. There were lots of rocks just off the road, and then a sandy bank that led to a stream, which led to the ocean. The rocks were covered in oysters, so it was very easy to get all the oyster samples we needed. We found three different species at that site and were able to collect all the oysters and water samples in about an hour.

Interestingly, there were two locations available for water sampling. One spot was an isolated pond influenced by run-off from the road, where the salinity was only 18 ppt. (The average salinity of the ocean is 35 ppt or parts per thousand). The other spot was more of a stream running from the land into the ocean only a few miles away, and the stream’s salinity was 30 ppt. As the salinity of the water can directly impact the parasites, some of which can only survive in high salinity, I opted to take water samples from both bodies of water so I could compare the differences. I’m hoping to get some really interesting results!

From the Field: Worth the Drive

Wednesday, December 19th, 2012

by Katrina Lohan

View from Rio Mar on the Pacific side of Panama at high tide (Carmen Schloeder)

On Friday, we ventured to a new location on the Pacific coast to hunt for oysters. Rio Mar is a beach site, so it is unlike our other locations, which thus far have been located in more enclosed estuaries. We headed out to Rio Mar in the hopes of finding some larger oysters in the tidal pools. Fortunately and unfortunately for us, by the time we made it out there, it was high tide. The view of the beach and surrounding area was spectacular, but we weren’t able to sample any oysters. I can’t say I regret going out there, though–what a beautiful beach!

From the Field: Hanging onto Mangroves

Monday, December 17th, 2012

by Katrina Lohan

First of all, our stuff arrived! After a few more phone calls to the customs office, everything went smoothly and all of our gear was delivered on Tuesday—not too shabby, really!

STRI biologist Mark Torchin attempts to climb a stream bank after obtaining oysters from the mangrove roots. (Katrina Lohan)

The next site on our list was called Bique, an intertidal area that has some freshwater input. Many sites on the Pacific side of Panama have large stretches of beach that are uncovered at low tide but completely underwater at high tide. So we are sampling at low tide, when the oysters on the rocks are exposed and much more easily accessible.

At this site, we decided to check out the mangroves first to see if there were any oysters attached to their roots that we could sample. While we found some, they were pretty difficult to get off. Our collaborator, Mark Torchin, thought it safest to strap himself to a mangrove, as the banks were made of soft mud and it is all too easy to fall into the stream. Additional acrobatics, such as scaling mangroves, navigating through root mazes, and climbing back up off the muddy banks, were required to get these oysters, but we prevailed and were able to walk away with about 30 individual oysters.

We then headed back out to scrape oysters off the rocks and found two different species, Saccostrea palmula and a species of Crassostrea, in the rocky intertidal zone. As our supplies had arrived, I now had the equipment necessary to obtain and filter water samples as well, so I walked out along the rocks to get a liter of surface water from the incoming tide. Part of my fellowship research involves comparing the different kinds of parasites in the water column to what is infecting and being filtered by the oysters. Water sampling is just one way of obtaining a more complete picture of parasite diversity in the different sites that we are sampling.

From the Field: Finding Oysters in Panama

Friday, December 14th, 2012

by Katrina Lohan

Katrina Lohan, attempting to scrape oysters off a rock at Punta Culebra, Panama. (Kristy Hill)

I would love to be able to say that I am a world traveler with loads of experience visiting other countries, but that would be far from the truth. Unfortunately for me, my passport has only a few stamps. (Two to be precise, as it wasn’t stamped for walking across the border into Mexico or crossing the border to have dinner in Canada.) So traveling to Panama to collect oysters has expanded my horizons in more ways than one!

In Panama, Kristy and I are working with Mark Torchin and Carmen Schloeder, scientists at the Smithsonian Tropical Research Institute in Panama. Our first sampling site was about a five-minute drive from the Smithsonian’s Naos Laboratory, which sits just outside Panama City on the Pacific Ocean.

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From the Field: Arriving in Panama

Thursday, December 13th, 2012

by Kristy Hill

Panama skyline (Kristy Hill)

I arrived in Panama City at 10 p.m. Saturday night, and as the plane started its descent into the city, my eyes widened at the sight of the city lights. It looked as if Clark Griswold had bedecked the entire city with Christmas lights! Tall buildings flashed extravagant multicolored light shows. I started getting that flutter of excitement in my stomach. I was about to spend two amazing weeks in Panama doing the science that I love!

I got through immigration and customs without incident despite my inability to speak Spanish well (yo hablo muy poco español). At any rate, I found my shuttle driver holding a sign with my name on it, so I felt pretty special as we walked out into hot and humid Panama.

My driver, Victor, showed me wonderful Panamanian hospitality. Luckily he spoke English very well and gave me a tour of the city on our way to the hotel. He recommended some places for us to visit if we had free time, and we talked about his experiences scuba diving in the Caribbean.

I arrived safe and sound at the hotel, where I managed to wake Katrina, who was already fast asleep with visions of sugar plums dancing through her head as I fumbled with my suitcases. I climbed into bed as well shortly thereafter and dreamt of Panamanian oysters dancing in my head…

Buenas noches!

From the Field: Game Plan for Panama

Thursday, December 6th, 2012

by Kristy Hill, SERC marine invasions technician

Katrina Lohan packs rubber gloves, Ziploc bags and other field essentials for a science expedition. (Kristy Hill)

Katrina and I leave for Panama City in next week, so we’re gathering supplies and mapping out our game plan. We’re stoked to get this project rolling—beautiful surroundings and mandatory snorkeling in the tropics won’t be such bad work!

The critters we’re looking for grow on coral reefs, mangrove roots, sponges, pilings, sea walls and rocks. Our goal is to collect at least 50 to 60 oysters of three or four different species from three sites along the Caribbean coast. At each site, we’ll take water quality measurements such as salinity, temperature and oxygen content. We’ll take additional notes about the oysters’ habitats, such as their distance from the shore, the depth of the water, their proximity to ports or marinas, etc. We want to obtain as much data (or information) as possible so we can better understand the environment where the oysters and their potential parasites live.

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