Chionoecetes opilio (top) and C. bairdi (bottom) from the eastern Bering Sea
Bairdis (Chionoecetes bairdi), or Tanners, are cousins of snow crabs and support fisheries both in southeast Alaska and the eastern Bering Sea (EBS) (yes, they’re called Tanners, even though ‘Tanner’ can also refer to other Chionoecetes crabs).
My project was a first step at answering the question, "Are the adult crabs in Kachemak Bay the source for new recruits or is the bay dependent on upstream sources?" I looked at the presence and abundance of brachyuran larval crab across the inner/outer Kachemak Bay boundary over an entire larval crab period (March - October). The idea was to determine what crab exist as larvae in Kachemak Bay, when they are present in the water column, and (hopefully) if they were coming or going?
2. You are creating an ID guide for brachyuran crab larvae. In your opinion, which crab has the cutest larvae?
The crab with the cutest larvae is a hard decision. I get most excited when I see a Dungeness larvae because they were the least abundant. They are all fascinating... I don't know if cute is the word I would use. Perhaps when they become megalopae, then they look like cute miniature 'crabs'.
YIKES! A Dungeness crab zoea!
Dungy megalope -- way cuter
3. What was the most difficult part of your project and how did you overcome it?
The beginning seemed the hardest... just figuring out how to make the sampling work effectively. Basically, making words on paper happen in real life with a real boat, real weather issues, and steep learning curves. Try, try, and try again. Relax, laugh a little, then try again.
Megan sampling, for real!
4. You just defended your thesis (congrats!). What’s next?
I've been working full-time since September of last year... so, I am looking forward to 'just' working full-time and using a different part of my brain... hope to take pottery this semester at the local campus.
5. What is your favorite piece of crab paraphernalia?
Remember that sweet male snow crab who protected his female by hoisting her in the air? Well, I have hard evidence that they did in fact mate:
spermatheca from the lucky lady
Pretty awesome, huh? Joel Webb removed the spermathecae from my females after their mating experiments to see if copulation really occurred. The dark color is from the spermatheca's reaction to a foreign object (the spermatophores). Joel showed me how to dissect the spermatheca so that I could measure the sperm load too! You can see that the male didn't quite, er, fill her up:
So there you have it! The proof is in the spermathecae!
Methyl farnesoate (MF) is a sesquiterpenoid (5 syllables… try to use it in a haiku!) hormone, meaning it has a 15-carbon skeleton.
Methyl farnesoate's carbon skeleton. Get it??
It is produced in the mandibular organs which are glands, kind of like our pituitary gland. It is the crustacean reproduction hormone, but the tricky thing about it is that MF is also related to the insect juvenile hormone. What does that mean? When a juvenile crustacean, like a crayfish, has a high level of MF in its system before molting, it WON’T molt to a mature/reproductively active state. It will stay a juvie. It’s like your average 13-year-old boy (or 23-year-old boy…): hormones raging, but still basically an infant.
Miranda is my crab lab mate -- she's co-advised by Dr. Sherry Tamone (my advisor) and Dr. Ginny Eckert (my committee member) -- and my office mate in the Lena building, as well as my ELISA accomplice!
Degree: Candidate for Master’s of Science, Fisheries
Current City: Juneau, Alaska
1. Describe your project, in 4 sentences or less.
I study the growth physiology of red king crab (Paralithodes camtschaticus), specifically comparing wild caught red king crab (from Southeast Alaska) and hatchery-raised red king crab (from the Alutiiq Pride Shellfish Hatchery in Seward, Alaska). There are two aspects to my project: 1. is to determine how often the crabs molt (molt interval) and how much they grow with each molt (growth increment) 2. look at the fluctuations in circulating growth ecdysteroids (20-hydroxyecdysone) in the hemolymph throughout the molt cycle. Additionally, I conduct monthly beach surveys (during the low low monthly tides in Auke Bay) to measure the wild juvenile red king crab that live in the intertidal in order to help determine if there are any differences in growth that may result from rearing crabs in a laboratory over time. By understanding the early life history of king crabs, specifically how they grow and behave during their most vulnerable time (first few years of life), managers will be empowered to manage the fishery in a more informed and predictive manner; moreover, this research may be used to better classify (or “age”) young crabs that are encountered during surveys or other field research opportunities, giving managers and researchers a deeper understanding of how movement and behavior of differing age classes of juvenile king crabs in the field will ultimately affect the fishery into the future. (I know that last sentence is kind of long and a run-on but I only had four sentences!)
a red king crab's growth over subsequent molts (all photos scaled the same)
2. You were living in Florida before. What drew you to Alaska?
I loved working in the warm waters off of Florida but couldn't pass up the opportunity to work on an amazing crab fishery in the last frontier. It really was the project and my advisors that drew me to Alaska. The bonus is that Southeast Alaska is an amazing place to live and work!
at work on ADF&G's R/V Medeia with a blue king crab
3. What has been the most challenging aspect of your project? The most fun?
The most challenging part has been learning time management. It's a real challenge to fit in all of your research as well as classes, meetings, lab work and all of the other little things that tend to come up! The most fun is, without a doubt, working with live animals. Even though it can be challenging and time consuming, it brings me a lot of joy watching their behavior and watching them grow. I often feel more like I have thousands of little pets rather than research animals!
first stage juvenile red king crab
4. Will you continue to work with crabs after you graduate?
I sure hope so! I love working with juvenile shellfish and I really do prefer working with decapod crustaceans (e.g. crabs, shrimp, lobster, etc.). I am considering continuing on with my education and pursuing a PhD but I haven't made any decisions yet.
5. What is your favorite piece of crab paraphernalia?
When working with a specific organism or class of organisms, you really do tend to accumulate a lot of paraphernalia! Without a doubt, my favorite is my crab beach ball that I got for my birthday from my sister-in-law. I also really love the crab business card holder that I got for Christmas.