Meyer-Kaiser lab

At low tide, the water level gets so close to the shallow corals that you can see them super clearly, even from the boat. I took this photo at one of our study sites, Mecherchar, standing on the boat. It doesn't even look like there's any water there! Palauan women wear these flowers behind their ears sometimes. We found a tree with them outside a restaurant in town.  There are little geckos everywhere in Palau - sometimes even indoors. This little guy was on the stairs leading up to Cas and Matt's apartment.  Nudibranch!! A giant Acropora coral at one of our sites, Taoch. Photo by Cas Grupstra.   Cardinalfish! Photo by Cas Grupstra.  

Right now, I am sitting at the kitchen table in Cas and Matt's apartment. The air conditioning and window covers isolate me from the Palauan sun. It's silent except for the low drum of a fan and single chirping bird outside. Each member of my team has a laptop screen in front of them. Some of us are analyzing data; some of us are working on papers; one of us is writing blog posts to procrastinate doing any "real" work. We had discussed visiting a museum later this afternoon, but there's no pressure. It's a slow day.  How in the world could there be a day like this in the middle of a field trip, you ask? Good question. Honestly, it's because I designed our trip that way. I'm in my 30s; I'm on the tenure track; and I would like to think I've gained a little maturity over the past few years. Gone are the days when I work 18 hours straight for weeks on end, then utterly collapse as soon as I get home. I can't do that to myself forever; it'

When you're in one place for a while, you get to see things happen around you. People come and go, events take place, and things can change during the course of a long trip. That has been the case for us in Palau. We've been here for a month already, and in that time, some interesting things have happened.  The Taiwanese navy showed up. We saw their ship in the port in Malakal on the way to our study sites one day. The ship was what you would expect for a navy ship, no matter what country it came from - large, utilitarian, gray. A string of colorful flags stretched from the bow up to a mast, across the middle of the ship, then down to the stern. Small white boats clustered around a rope ladder on one side of the ship, presumably to bring sailors ashore. And oh my goodness, did they come ashore. It felt like the island was drowning in tan uniforms. Seriously, there were so many of them.  Matthew talking about corals to the sailors. A group of the Taiwanese sailors came to check

These are some photos I took with my macro lens while I was supposed to be looking for baby corals . I'm not sorry.  Sea star! A giant clam, Tridacna sp. I have no clue what this is, but the polyps are pretty. This guy swam around us for several minutes. It's a Persian Rug Flatworm, and you should totally check out this BBC segment about their reproduction .  The tentacles of a Fungia coral. A Goniopora coral

As we've been doing the  recruit hunt transects , I've been swimming around on the reef with a macro lens on my camera. Obviously, I'm going to take photos of cool animals I find. Prepare yourself for this onslaught of biodiversity! A coral, Porites cylindrica A pipefish at our site, Ngelsibel Nudibranch! A coral, Montipora sp. Tentacles of a large anemone

Have you ever gone geocaching? I went once with a friend when I was living in Germany, and it was fun. You find the coordinates for a "cache" in an online database and then go hunting for it using nothing but a GPS and your wits. The one we found was in a public park in Bremerhaven, and unfortunately it was near a creek that I ended up stepping in, filling my boots in the process. The cache can be anything. Ours was a small waterproof case with a log inside of all the geocachers who had found it.  I was reminded of geocaching this week because my team was dealing with very precise locations. Not for caches, but for corals.  Maikani and I on the boat (with our driver, Kaiton) after a day  of coral sampling and georeferencing. Photo by Cas Grupstra. You see, we're trying to determine whether different lineages of Porites lobata corals are reproductively isolated. In order for corals to cross-fertilize, their gametes have to meet. We know that different lineages co-occur at

"There's a million things I haven't done, but just you wait" - "Satisfied" from the musical Hamilton by Lin-Manuel Miranda It started in 2018. I put some tiles down on coral reefs to collect new recruits, and I got a few . Not a ton. It was the first time I had conducted research on reef-building corals, and I was surprised by how few individuals I caught.  One of the recruits in our quantitative dataset. Then in 2021, I tried again. I put tiles out on the reefs and left them for longer . Maybe I would get more that way. It kind of worked, but not spectacularly. I got a few more .  Then it became an obsession. Where are all the baby corals, and why can't I catch many of them? I dispensed with tiles and checked for recruits on coral rubble, their natural habitat. It kind of worked. Then I dispensed with collecting samples and just started taking photos of baby corals wherever I found them. That worked really well . We collected hundreds of photos and r

I love recruitment! Honestly, putting a panel down in the ocean and coming back to see what's grown on it is so fascinating. It feels like magic sometimes - I just leave some very simple pieces of plastic or limestone or glass in the water, and then I get data. There are usually very clear patterns , too. I have studied recruitment in the high Arctic , in Oregon , in Massachusetts , and now in Palau.  One of the coral recruits on my tiles, magnified 30x. For this experiment, the recruitment panels I'm using are limestone tiles, the kind you would use on a fireplace or a kitchen backsplash. I literally bought them at Home Depot. We have put those tiles everywhere. They sit in the bins with our corals so the larvae settle on them. They get deployed on racks next to PICRC for us to monitor closely. They are transplanted out at our study sites. We use limestone tiles for everything.  Every trip for the last two years, we've left tiles behind at each of our study sites. This

"It's not stress that kills us, it is our reaction to it." - Hans Selye This trip, we are absolutely determined to achieve our main goal: an investigation of the factors causing selective mortality in the post-settlement stage for Porites lobata corals. We modified our transplant experiment to ensure at least some corals survived to the end this time. As an additional back-up, we kept some corals in the lab and simulated the conditions they might encounter on the reef.  There are several things that can stress corals out - water that's too hot or too cold, too much light, too little light, too much sedimentation, predators, competitors like turf algae - honestly, it's a wonder any of them survive at all. The post-settlement stage is an absolute gauntlet for marine invertebrates. That's why I've gotten so interested in studying it and even invented a special camera to do so.  Some of our coral babies on glass slides in the experiment. Each round beige d

I want to tell you about two more experiments I'm doing in Palau. At this point, if you're starting to get confused by all the different things my team has going on, don't worry, you're not alone. Even Maikani made a comment the other day in her signature exclamatory voice about the number of different experiments. It's a lot, I know. But can you blame me?  I want to figure out if Porites lobata larvae can disperse away from their home reef and colonize a new place. This is super important to understand because the heat-loving corals in the lagoons might have to repopulate outer reefs after a future bleaching event. If all the corals on the outer reefs are dead or bleached , could the larvae from inside the lagoons even make it out there? If they settle, could they survive ? Does spending a long time drifting in the water lead to negative impacts later in life?  Porites larvae just love settling in the ridge at the bottom of my containers. Every brown dot is a lit

We collected Porites lobata corals and brought them into the lab. We monitored them for spawning for 10 straight nights. We collected their gametes and mixed them together to fertilize. We removed any unfertilized eggs, diluted, and cleaned the cultures. We changed their water. We concentrated the larvae and distributed them among settlement bins . We provided them with limestone tiles and a chemical cue. We checked to make sure they had settled. We counted and measured them.  Coral settlers on a limestone tile. And then we could start our experiment.  Larval biology is a multi-step process. Any experiment you do has so many components: spawning, rearing, settling. Since our experiment focuses on the post-settlement stage - right after the larvae settle on the reef - we had to go through almost all steps in the life-cycle before we could start our experiment. But we made it. The larvae settled on our tiles, and we were good to go. Our main experiment - the one that got us funded -

"You are only as much as you settle for." - Janis Joplin Porites lobata larvae develop quickly. We discovered this last year. Eggs get fertilized one night, become larvae by the next day, and are ready to pick a spot on the seafloor just a day after that. The timeline is convenient because we don't have to stress and change their water and try to keep them alive for days on end, but it also means we have to be ready for settlement quickly.  Just two days after getting our first spawn , we had to settle our corals. The process is relatively easy. We culture the larvae in plastic bins, so getting the larvae to settle just involves adding a tile to the bin for the larvae to settle on and a cue that makes them want to settle. Easy, peasy. Yeah, you're not that naiive. Of course it's more complicated. Yes, we culture the larvae in plastic bins. Yes, we also get them to settle by adding a tile and a settlement cue to their bins. But there are several steps in between. 

I pulled into the driveway at Maikani's house at 8 am. I had an hour to shower, change clothes, eat breakfast, and get back to the lab. Honestly, it felt a bit weird. I had crashed on the couch in Cas and Matt's apartment at PICRC after we finished with all the spawning work and then stayed to collect data points at 4 and 7 am. I was wearing the same clothes as the day before and probably looked pretty disheveled. An uninformed onlooker might conclude that I had spent the night with a date and was doing the proverbial "walk of shame" as I came home the next morning. Tell you what, if I had a date that night, it was with Coral Number Thirteen , our stud male. But this was no walk of shame. It was a stride of pride.  Porites lobata larvae. I am so proud of my team . We had a banner April spawning season. Out of 100 corals we collected from the reef and kept in our tanks, 16 individuals spawned. That's the same percentage we got last year , but a higher total numbe

A very proud Cas with his cryo rig. Friends, I want to tell you about two strategies we tried out this spawning season to freeze our little babies in time. Yes, I mean that literally.  One of our major questions was whether corals from different genetic lineages can cross-fertilize one another. If they can't, then our lineages might be different species. We're keeping track of the exact time when each individual spawns, because that way we can see if there's any temporal reproductive isolation. If you spawn at different times, your gametes may never meet. But we also want to figure out whether the mixing of eggs and sperm from different lineages can produce viable embryos. It's impossible to monitor every coral on every reef, so we brought about 100 of them into the lab. That's a very small sample of the population. What if individuals from our different lineages just happen to spawn at slightly different times, and we don't have their gametes at the same time?

A Porites lobata coral about to release gametes. It was 7:30 pm, and we were on spawn watch. We had gotten eggs and sper m from our coral colonies the night before, so we watched our potential parents with eager anticipation. A second night of spawning was pretty much expected. Who would be the first to release their gametes?  I should have known which coral it would be. It's always the same one. He goes early , and he goes big. Coral number thirteen, our stud.  What's cool about Thirteen is that he belongs to a distinct genetic lineage with high thermal tolerance. He and his brethren basically never bleach. They live inside these semi-enclosed lagoons in Palau's Rock Islands where the water heats up during the middle of the day. So when a bleaching event happens, to them, it's just an average day. Thirteen thrives in the heat. And he produces a lot of sperm.  Maikani collecting sperm from a coral. One of our goals for this trip is to figure out whether the different g

A male releasing sperm - it looks like smoke. "Therefore keep watch, for you do not know the day or the hour." - Matthew 25:13 We had been on spawn watch for six days. Every evening, we gathered in the lab and took turns checking on our corals every 20 minutes. This went on for four hours each night. Patiently, we waited. Diligently, we watched. Other species of corals were spawning early, and we didn't want to miss our chance. We were careful to only shine red lights on the corals, so they didn't think it was daylight and decide not to spawn. We checked the water off the dock to see if any corals were spawning in the ocean. We were so careful.  It was Easter. Our sixth day monitoring our corals. Three days after the full moon. Two hours after sunset. Matthew and I did a lap around the dock to see if any spawn slick was visible on the surface of the ocean. "It kind of smells like a spawning night," he stated. I couldn't tell if he was joking or serious

Every country has its own little quirks that make life interesting. Here are three that I've noticed for Palau. 1. Roosters. It’s pretty common for Palauans to keep chickens. Eggs that are shipped in from the U.S. are actually expired by the time they reach a grocery store in Palau, so if you want eggs, your best choice is to get a little flock of your own. Plus, chickens are one of the few meat animals you can feasibly maintain on an island as small as Koror. Ok, so the stereotype is that roosters crow at sunrise, but that is an absolute myth. Yes, roosters crow at sunrise. They also crow every other time of day. They crow constantly. They crow to hear themselves crow. I will always associate Palau with the sound of a hundred roosters crowing all day long. 2. Hot showers. This is just a funny anecdote. I have been to Palau so many times that I’ve lost track, and the only time I’ve had a hot shower was when I stayed in a fancy hotel on my honeymoon. The water heater at PICRC h