Perfect timing

I got to the lab at 6:30 am. I was due at the Massachusetts Maritime Academy for all-day safety training starting at 8, so I wanted to check on my fluffy anemones beforehand. Just to make sure they weren't spawning, you know? Over the past few weeks, I had tried light shock, heat shock, cold shock, combination light-heat shock, and just standing over them, staring them down. Nothing seemed to work. They probably weren't going to spawn for me. I pretty much knew it was going to be a useless trip. But the literature said spawning can happen spontaneously right after dawn, so I had to check. Just to be sure. 

You can probably tell where this is going. 

Yep, I had sperm in one bin and eggs in another - from two different females, even! All three spawning individuals were different colors, too! That meant I had gametes from a cross-section of the population. Amazing! 

Metridium senile eggs (and one dividing embryo!)

I looked at my watch. 6:45 am. I was due in Bourne at 8:00, and it would take me 30 minutes to drive up there. That meant I had 45 minutes to start an experiment that I had wanted to do for 5 years. Right. As I gathered materials, my mind flashed back to April 2022, when my team spawned Porites lobata corals in Palau. The anemones before me, like those corals, apparently spawn on their own sweet time. If I was experimenting with clams, I would inject them with serotonin to induce spawning. If it was slipper limpets (Crepidula fornicata), I would crank up the temperature. For sea urchins, all you have to do is shake the adults and then turn them upside-down in a bowl of cold water. Tube worms spawn as soon as you push them out of their tubes. But not anemones or corals. Honestly, based on my data, it seems the spawning cue for fluffy anemones (Metridium senile) is a busy schedule. 

I've never worked with Metridium before, so I wasn't exactly sure how the gametes would want to be treated. For most marine species, I would mix about a turkey baster full of eggs and and just a few mL of sperm in a 2L jar. But for corals, sperm limitation is a big concern and you want your gametes at higher concentration. Which one would work better for my fluffy anemones? In the end, I decided to try both. Thankfully, the jar method worked, so I actually had larvae by the end of the day. 

It was a very exciting morning and a very full week. I am relieved that my anemones spawned and excited for the experiment ahead!