More fun with herbivory

School started on Wednesday, which means that I had to leave Nahant and go back to Providence and actually sit in classes. My classes this Fall are fairly interesting - Conservation Biology, Methods of Applied Math, an Introduction to GIS - plus I'm auditing an experimental design class. Still, interesting classes are less exciting than actual research, especially actual research that still needs to be done. I have a very nice 3-day class schedule (Tues-Thurs) so Friday found me right back at the Marine Science Center working, again.

This summer I ran a big herbivory experiment looking at Lacuna snail preferences among different species of subtidal algae. This weekend I'm trying to figure out if other herbivores like isopods may also be important in grazing the algae.

The baltic isopod, Idotea balthica. This is a fairly large individual; the ones we find in our algae are generally around 1 cm in length.

To do this we're running a much smaller-scale pilot experiment with just a couple of algal species and only 6 replicates each. The isopods go in little modified petri dishes with a similar structural theme to the containers I used for the Lacuna experiment - identical amounts of algae in both chambers of the dish, herbivores in one chamber.

One of my petri dishes. The right chamber has herbivores; you can just see an isopod at the top-right of the tag number 08. The left chamber is herbivore-free to account for loss/gain of mass that is not due to herbivory.

The overall setup. Petri dishes are zip-tied down to the aqua mesh to keep them submerged. You can see that they are arranged nonrandomly because my arms are short and I can't reach the area in the middle right of the water table. They are interspersed, though...

Scuba Smurf did a dive to check that everything was well attached and working.

Scuba Smurf approves of this experimental setup.