Snail survey (and a horseshoe crab)

Well, obviously it's been a while. This is mostly because I've been writing a lot and that's not really good inspiration for a) writing more for fun or b) writing about things that you (presumably not a member of my committee, given the odds) want to read.

In brief, since my last post I got a paper accepted (more on that when it's actually out), and have been frantically trying to finish up my dissertation.

Today I went out in the field for the first time in 4 weeks. I know this because apparently it is a supermoon again, and the moon sure was beautiful as I was driving to the field this morning. I didn't really have to go out, but I wanted to -- and as I'm not sure how many more times I'll get in the field while I'm in my present location, I'm glad I did. Plus, I got some more C. fornicata babies for a last-ditch attempt at an experiment.

There were lots of birds out today, and this horseshoe crab that found herself stranded well above the tide line. She has dug into the sand to keep her undersides (especially her book gills) damp.

Large female horseshoe crab, with my hand to scale.
She's decorated with a Crepidula fornicata and some barnacles.

I also found all of the common intertidal snails that exist at this site. The only species I didn't see (alive, anyway) were the two large whelks and the moonsnail. Those three are all predators that live subtidally and bury in sand -- it's very, very rare to spot them crusing around in the mornings, though I see their empty (or reclaimed) shells all the time.

In addition to the three species of Crepidula discussed in the last post, I turned up these guys:

Lots of Litorina saxatilis (rough periwinkles) on some rocks. These guys give live birth to their babies (viviparity). They're common all over both sides of the Atlantic, and in Europe are being heavily studied to understand how new species form. Because they disperse so little, populations of snails seem to have genetically adapted to different habitats they live in (ecotypes).

Contrast those little guys with the snail on the left in this photo. This is L. littorea, and it's shown up on the blog before. It is the common periwinkle, introduced from Europe, and has planktonic larvae. Because of those larvae, its populations are much more mixed than the ones of L. saxatilus. The snail on the right is Nucella lapillus, first appearing on the blog here. I don't usually see them at this site but I know they are there, because I often find their vase-shaped egg capsules attached to the underside of empty C. fornicata shells.

Ilyanassa obsoleta, the mud snail. Incredibly common here and very good at getting in my shoes. They make appearances on the blog more often than not, I think, because they're really everywhere.

Here's hoping I get out in the field again this season -- it's been very light this year, with not even much lab work. My office makes me crazy. But either way, it was a good morning and worth dragging myself out of bed.