Monday, April 25, 2011

Happy Easter!

I hope everyone had a wonderful Easter Sunday! I know for many people, an egg hunt was included in the festivities; there’s an egg hunt going on as I type this here at the UAF Juneau building. What colors did you find?

Just the beginning of my pile o' eggs!

So far, I’ve found some orange and purple eggs (and a white one), which makes me think of crab eggs!

the many colors of snow crab eggs/embryos

Moriyasu and Lanteigne (1998) color-coded the stages of development in snow crab embryos, so that when you catch females, you can determine how far along they are in their clutch maturation:

Moriyasu and Lanteigne's color scheme

Biological Field Techniques for Chionoecetes Crabs (Jadamec et al., 1999) and Biological Field Techniques for Lithodid Crabs (Donaldson and Byersdorfer, 2005) also describe the different categories for egg condition, which refers to embryo development. They include pictures of actual clutches that scientists can use to standardize different surveys’ data.

a myriad of egg colors:
the top clutches are Chionoecetes'
while the bottom are different king crabs' clutches

Based on these pictures, my eggs were a mix of uneyed snow crab Chionoecetes opilio embryos (orange) and uneyed king crab Paralithodes camtschaticus or P. platypus embryos (purple). The white egg could possibly be an eyed golden king crab Lithodes aequispinus embryo, or just a snow crab dud egg (unfertilized). Either way, it had two Butterfinger® chocolate eggs in there, so it was worth it!

Crab Egg Reading:
Donaldson, W., and S. Byersdorfer. 2005. Biological field techniques for Lithodid crabs. University of Alaska Sea Grant. AK-SG-05-03, Fairbanks.

Jadamec, L. S., W. E. Donaldson, and P. Cullenberg. 1999. Biological field techniques for Chionoecetes crabs. University of Alaska Sea Grant. AK-SG-99-02, Fairbanks.

Moriyasu, M., and C. Lanteigne. 1998. Embryo development and reproductive cycle in the snow crab, Chionoecetes opilio (Crustacea: Majidae), in the southern Gulf of St. Lawrence, Canada. Canadian Journal of Zoology 76: 2040 – 2048.

No comments:

Post a Comment