Sunday, July 21, 2013

Internet quiz and scyphozoan medusa -- all in a day's work

I've scuttled off to points north to find snails. It's been a delightful trip, but I'm not done, won't be back for a while, don't want to write about the experiment I threw in the field before I got back (not literally threw, but close), so instead, here is a fun marine inverts memory quiz to play with. Play several times, there's some new animals each time.
A jellyfish washed up on the beach. I successfully avoided getting stung today, despite the fact that there were dozens in the water and on the beach and I wasn't paying the least bit of attention to them (too busy snail-hunting).

Friday, July 12, 2013

Marine invert sighting of the week

ETA: Thanks to the wonders of social networking, the ID of the worm is now in question. Without the animal I don't want to say anything for sure, but it may in fact be from a different polychaete annelid family (Onuphidae).

The title of this post is actually a misnomer, because I never saw the animal in question. I was collecting snails at a new location yesterday. The beach looked like this:

Beach covered with worm tubes.
The silty sand was being held together by dozens of large tubes. Tubes on a beach are not new to me. Many polychaete worms (distant relatives of the familar earthworm) make tubes out of sand or other materials on the beach. These animals live in their tubes, pumping food and oxygen down into the sediment to well below the level where such resources are normally found. The tubes also add structure to an otherwise unstructured area, and can change erosion and other dynamics of the beach quite drastically.

Normally the tubes I see are small, just a couple of centimeters above the sand. These were big honking tubes, made of a parchmenty substance with lots of pebbles and bits of shell attached.

Worm tube, with hand for scale.
It took me a little while, but eventually I realized that these tubes must belong to a group of worms that we showed our students in Invertebrate Zoology this year. I didn't have a shovel, so I wasn't able to uncover these massive tubes and check for sure. But I was in the right area, and the tubes look right, so I'm confident that I can claim to have seen this guy:

Chaetopterus spp. Photo from Wikipedia.
 Man, these worms are bizarre looking, are they not? The head end is at the top in the photo above. Each of the different segments has evolved to specialize on a different task. Some pump water through the burrow, some aid in various parts of the feeding of the organism (they feed using a mucus net to filter particles from the water).

For me, invert-lover that I am, it was very exciting to find and identify a specimen that I had previously only seen in the classroom. Plus, I found what I need for my research, so it was a good morning all around.

Friday, July 5, 2013

Cycles, vacation, and my brief absence

My job is very cyclical. As previously discussed, I am heavily dependent on the tides to determine when I need to go out in the field and get animals for my work. There really isn't much leeway in when the tides will be good, which means that for at least one week out of the month, I have to plan to do as much collecting work as possible (especially in the summer). It also means that when I get up on a collecting morning and it is too early or rainy or unbearably hot or there might be too much traffic because of a holiday weekend, I don't really get to go back to sleep.

On top of that is added the reproductive cycle of the snails. I am lucky in that Crepidula reproduce for a very large window of time, at least in my location. I can reliably find field-collected larvae to work with from April/May until October. This is in sharp contrast with, say, coral reproduction, which is frequently centered on just a single night of the year (and woe betide the researcher who misses that night). Perhaps a post on synchrony in corals is something I will do in the future.

Still, despite this thankfully broad window to work with, I find myself running around doing half-a-dozen different experiments every summer, trying to capitalize on the field season as much as possible. And, of course, the academic calendar does not line up perfectly with the animals, meaning that in both spring and fall there is a painful period where I am doing both my academic and my field work.

None of that is to justify why it has been a month since I posted, though. It turns out that the last couple weeks looked something like this:

One of my field sites, mid-June, while I was deploying an experiment.
Snowbird, Utah, site of the 2013 Evolution meeting, taken < 24 hours after the previous picture.
Zion National Park, Utah.
Yes, I took a glorious week off to go west (don't panic, I had an experiment running itself while I was away). Both the scientific meeting and the brief vacation afterwards were glorious, but mostly invertebrate-free. Actually, that's a complete lie, since we saw many beautiful insects in both the mountains and the deserts, but no marine invertebrates. I was disappointed not to see a tarantula or scorpion in the desert, but that's pretty easy to say from the comfort of my couch. And there were no snails spotted in the mountains, though I did see a single freshwater snail in a reservoir near Zion.

When I returned to the humid Northeast, I found my snails in good condition, so I'm getting painfully back to the grind, trying to get as much done as I can before the academic year cycles back around again.