Island County
Camano, WA
Molt Search Report
User Submitted Data
Observation Type: Timed survey
Molts/crabs found: Yes
Also submitting Dungeness crab molt data: Yes
Number of Dungeness crab molts found: 49
Sex of Dungeness crab #1: No abdomen present
Carapace width of Dungeness crab #1: 635
Sex of Dungeness crab #2: No abdomen present
Carapace width of Dungeness crab #2: 572
Sex of Dungeness crab #3: No abdomen present
Carapace width of Dungeness crab #3: 508
Sex of Dungeness crab #4: No abdomen present
Carapace width of Dungeness crab #4: 478
Sex of Dungeness crab #5: No abdomen present
Carapace width of Dungeness crab #5: 444
Sex of Dungeness crab #6: No abdomen present
Carapace width of Dungeness crab #6: 444
Sex of Dungeness crab #7: No abdomen present
Carapace width of Dungeness crab #7: 444
Sex of Dungeness crab #8: No abdomen present
Carapace width of Dungeness crab #8: 414
Sex of Dungeness crab #9: No abdomen present
Carapace width of Dungeness crab #9: 381
Sex of Dungeness crab #10: No abdomen present
Carapace width of Dungeness crab #10: 350
Popular crabbing spot, lots of adult crab shells from crabbing, just put Two in photo Also some shells were curved? Maybe animal died at soft shell stage?
1 Comment. Leave new
Hi Renee, your observation about the curved molts is something. I’ve wondered about before, so we asked our resident green crab expert Sean McDonald about. He suspects it’s something to do with materials science! Exoskeletons are an unevenly distributed blend of largely inorganic calcium carbonate (70-80%) and some organic chitin/lipids/proteins (20-30%). Plus fresh molts can be up to 30% moisture by weight, also unevenly distributed throughout the layers. It turns out they’re made of layers of different orientations, like plywood, which gives it strength, but also gives that unevenness that could lead to some layers shrinking/tightening faster or differently than others. That uneven material mix & moisture distribution is his thought on what’s driving the curling effect on some molts. “Much the same way that some leaves dry flat and others curl”, he says. Thanks for the question! Sure is interesting to learn alongside you! -Lisa