Bleaching pairs

You might not know this, but Palau is currently experiencing a coral bleaching event. We found out the day before we arrived, when PICRC posted on their social media that researchers were going out to monitor bleaching at sites around Palau. 

One of our coral pairs at Risong

PICRC actually has a really unique community-based monitoring program. They engage citizen scientists around Palau to make periodic observations, and when those community members notice bleaching, they alert PICRC. The research team is activated and collects data from 80 sites within 3 weeks. It's an incredible feat that results in thousands of photos and tons of data. Using these observations, PICRC staff can keep track of bleaching extent, duration, and mortality around Palau. I think using the citizen science observations is a really unique and effective way to engage the community and gain valuable information at the same time. 

Thankfully, this bleaching event doesn't seem too horrible. Corals are bleaching, but not every coral. Some sites are harder-hit than others, and some species are harder-hit than others. The patchy nature of the bleaching actually meant that our team could use it as an opportunity. By studying corals that are bleaching or not, we can understand what makes some corals more resilient. Cas suggested that we seek out corals in pairs: one bleaching, one healthy. The pairs had to be the same species (our study species, Porites lobata), be right next to each other, and be in different states of health. By collecting and comparing these paired samples, we can better understand why some corals bleach and others don't. 

We know that genetics influence thermal tolerance - there are some groups of corals that are genetically distinct and can resist bleaching better than others. But there could be other mechanisms at work too: algal symbionts, helpful microbes, even gene expression. Our samples might show multiple interacting mechanisms that drive thermal tolerance in corals. 

I'm really glad Cas suggested the "bleaching pairs" study, and I'm looking forward to seeing the data!