working on intertidal and subtidal plots

Elaine (Jay’s technician) and I went out this morning to work the low tide. I had to replace the buoy marking my subtidal plot that drifted out into the harbor yesterday. I was surprised that it had stayed anchored fine for a week and then just drifted out into the harbor, but apparently the line had been wrapped in kelp and seagrass and that acted like a sail that caught in current.  Good thing I wrote my number on the buoy. It was nice to get it back with weights in tow (weights are surprisingly expensive).

I dropped the weights with buoy attached this morning. I added two stakes to drive into ground to help secure the line, I also think I will add a concrete flowerpot to be sure. That buoy is not going anywhere!  I will pound in the stake and attach the pot this afternoon when dive.

This morning we also counted missing shoots from my intertidal plots (9 and 3) and measured the shoot density of surrounding eelgrass. I wanted to do 10m transects directly north and south of the plots, but the disturbance from clam diggers was so bad on the north side that I had to run the transect parallel to the northern plot (just east of the plot).

I’m a little concerned about the clam diggers. They cause so much destruction and I would be so sad if they dug in my plot. So far they have been respectful (I have PVC poles lining the plots and pin flags at each shoot), but today we saw a guy out there that said he had thought that the plot was there because little kids were playing in the mud! I put lamented labels on my plots at Westside Park today, but I’m not sure they are big enough, and I actually think many of the people who go clam digging most often may not be able to read English (they often don’t speak English).

I think I might make a no digging sign with a picture!

Elaine was helping me today (yes I convince techs to dig in the mud at 6am on holiday weekends!), which was great. After survey the intertidal reciprocal transplant plots we continued clearing my plots for the relatedness experiment.  Five 1 by 11 m  plots to be cleared and we had almost 3 done when we came in today (2 days of work).

Highlight of the morning: Elaine found an octopus in on the mud flat!! Sea gulls had caught it and were trying to eat it. Elaine rescued it and we got to check it out for a while and return it to deeper water. It was missing a tentacle but I think other than that it was OK.  I looked it up and I’m pretty sure it was a pacific red octopus (Octopus rubescens), which apparently like kelp beds but can be found in both rocky and sandy/muddy bottomed intertidal habitat. Cool!

In the afternoon I dove with Sonya at my subtidal plot

Agenda:

1. Anchor buoy with stakes and cement filled flowerpot. – Completed with no problems.

2. Hammer in pole with light/temp logger. – Completed with no problems.

3. Check plot and record which shoots are missing. – Completed with no problems (only 3 missing shoots!).

4. Do two 10m transects measuring eelgrass shoot density every meter (one transect to the north and one to the south). – Completed the the transect to the north but not the south.

Everything went smoothly. Gorgeous day, decent visibility, good dive buddy!  Counting shoots in quadrats was harder than expected. The visibility at the bottom is bad and gets worse as soon as I touch anything. I ended up counting shoots but touch, but it was a bit hard with gloves on (even thin ones).  I’m how accurate it was. I think it worked OK though.  I’m not sure if I could tell if the shoots were reproductive or not in some quadrats.

I saw a bunch of crabs this time and big ones too. Not sure what kind they are, but will look it up.

All in all an excellent day!

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