Wild Elysia: Sea of Cortez Edition (Part Four)
Things were looking great. We had almost 20 slugs, protocols seemed to be working, and the students were becoming comfortable with all of the procedures.
It was time to get some Elysia chloroplast DNA from. Fortunately for the slugs, we did not need a lot of tissue. All we had to do was knock one out, and remove a piece of parapodium. As we showed before, it’s easy to paralyze a slug by soaking it in a magnesium chloride solution that matches the ionic strength (i.e., is isotonic with) of their bodily fluids. This solution rapidly enters their bodies and stops all neural signaling. After 15 minutes, the selected E. diomedea was relaxed and flat as a pancake.
After a quick snip, she was back in the tank, and roaming around within a few hours.
After that,it was time to extract the DNA. The crew got started, extracting DNA from the slimy slug piece, along with a fresh piece of Ulva. There was no time for PCR, but we did have a chance to do one more survey of the area in front of the station.
The conditions were not great, in that the water was somewhat cloudy and surgy by the time we got in. Nonetheless, we got a chance to explore and enjoy the sea life. We also found a few more slugs, which was definitely a bonus.
After that, it was time to pack up and get ready to be on the road. It was sad to be leaving the beautiful place and the people, but time, tides, and summer school wait for no one. We said our goodbyes after dinner. They continued the work for a few more weeks after I left, and I have been getting regular progress reports from Richy.
Hard to say goodbye to the slugs as well.
As always, we were up with the sun. We got on the road early, with tubes of DNA on ice.
The trip north was uneventful, and we arrived at the border in Mexicali on schedule. The wait at the border was about 1.5 hours, made somewhat less pleasant by the 112 degree F heat. We managed to get ourselves and the DNA across, and I was on my way home.
Summer classes started the day after I arrived back in Maryland, so it took a few days to find time to amplify the DNA we extracted in Bahia.It was worth it, though. Very nice bands for Elysia, Codium, and the second sample of Ulva. There were faint bands for the first sample as well, suggesting that the extraction was not a complete bust. With the DNA that was sent last week from the group, we now have a significant number of samples for sequencing, and, with luck, a nice story to tell. After the last round of sequencing did not produce usable data, I gave Macrogen a call. They have been amazing, and are in the process of troubleshooting the last samples I sent them. Keeping fingers crossed.
There was some sad news. The day after we left the station, temperatures shot up to a record 120 degrees F. With those kinds of temperatures, it was impossible to keep the holding tanks cool enough, and most of the slugs were lost. That was sad for the slugs, and meant that there would not be enough animals to finish the behavioral assays this year.
Nonetheless, as the Bahia program winds down this week, we can look back on a lots of success in terms of working out protocols, laying the groundwork for future population surveys, and acquiring DNA samples.