West Coast Green Crab Experiment

Waterproof labelling system (I hope)

It’s time to start thinking about this summer’s experiments! So far, I:

  • budgeted with my NSF PRFB and remaining PDS funds
  • coordinated with WDFW to get 180-200 C. maenas shipped for my experiment
  • met with two undergraduate summer interns that will be working with me this summer
  • claimed ESL space for my experiments

One thing I’ve been trying to figure out is how to label individual crabs. Last summer, I used paint pens to label crabs, but then the crabs climbed all over eachother and scratched the paint pens off! I decided to try a labelling system similar to the bee tags used in shellfish hatcheries. I tested the efficacy of waterproof paper labels adhered to crabs with either clear nail polish or superglue.

I used Write in the Rain paper and sharpie to make small labels to adhere to each crab. I would either cover the paper label with globs of clear nail polish or super glue to form a protective seal around the paper. With the nail polish labels, I noticed that the sharpie was starting to bleed because of the nail polish ingredients. I then let the crabs dry for five minutes. When I returned the crabs to water, I noticed that the nail polish would start to flake bits of filmy stuff into the water. The nail polish also smelled horrible, so I can imagine it being more toxic than the super glue. Once in the water, the super glue would become this opaque color. In total, I labelled ten crabs with nail polish and another ten with super glue.

PNG image

Figure 1. Crabs with labels

When checking on the crabs a few moments after labelling them, I noticed that the nail polish labels were already starting to come off! I’m leaving them in the sea table while I’m out. If the labels stay after 2.5 weeks, then they’re probably good enough for my summer experiment!

I’m not confident in either label, so here are a couple more ideas:

  • use a super glue accelerant to speed dry the crabs and prevent stress
  • use paint pens and then seal the paint pens with a coat of super glue so it’s protected from crabs climbing on top of eachother
  • use super glue to “write” on the crabs for a label if the super glue ends up being really stable

Going forward

  1. Finalize demographic data analysis
  2. Test formatting and analysis for one set of respirometry data
  3. Order 2023 experiment materials
  4. Test chiller and heater in ESL
  5. Order extraction materials
  6. Update methods
  7. Update results
Written on April 28, 2023