Pugettia producta

Common name

Northern kelp crab, Kelp crab, Shield-backed crab

Size

5cm in length and width of 6cm

Range

South Alaska to North Mexico, intertidal to 75 meters

Habitat

Open coast, tidepools, algae, pilingsurfgrass, dense kelp beds, eelgrass, and rocky shores

Identification

The group's common name is spider crabs because of their four very long spider like legs and two modified legs called chelipeds. The males have larger chelipeds but the females have longer legs. The juveniles are olive colored and adults are reddish brown with black spot on the thorax. The coloration is from their diet and environment. The thorax looks like police badge which is called carapace. The carapace is smooth, and on the edges are spines. The eyes are very dark and located a little behind the carapace. The abdomen has seven segments.

Pugettia producta

Reproduction

June to July is when the males and females engage intercourse. The eggs they may stay in the female's abdomen for two generations till they mature into adolescent crabs.

Food

Nocturnal eater mostly vegetarian in the habitats for bull kelp, rockweed, sea cabbage; if food is scarce it will eat barnacles, hydroids, mussels and bryozoans.

Predators

Sea otters, Sculpins, Seals and Seabirds.

Additional Resources

University of Michigan Museum of Zoology
Biota @ Evergreen