Graceful Kelp Crab

Biology/Natural History: The spines on the legs may help this crab hang onto the kelp and avoid being swept off. This crab does not usually decorate itself much, but it does so occasionally. Predators include halibut, clingfish, kelpfish, and woolly sculpin. During mating, the male lies on its back and the female stands above, facing him. Ovigerous females have been found through most of the year in Puget Sound. Females have around 6200 to 13,000 eggs per brood. The long legs of this crab are especially agile, and they can reach far above and behind them for defense.

Eelgrass and kelp; both on outer coast and on protected shores. Also on pilings in strong currents.

The rostrum of this small majid crab consists of 2 flattened processes which diverge from the base. The carapace is longer than wide. It has a prominent, sharp lateral tooth near the middle of the carapace, and another wide, flattened lateral projection anterior to the middle. The dorsal surface of the carapace has tubercles. The distance between the eyes is about 1/2 the carapace width. The dorsal surface of the merus of the cheliped has a distinct ridge in males, but less distinct in females. Carapace width to 4 cm in males, 2.8 cm in females. Highly variable in color; often brown, yellow, or red but sometimes white, orange, pink, or blue. The walking legs often have light-colored bands. The chelae are bright blue near the end, with orange or red tips.

How to Distinguish from Similar Species: Pugettia richii has a narrower anterolateral tooth, plus does not have a distinct ridge of tubercles on the merus of the cheliped and does not have the orange and blue tips on the chelae. Oregonia gracilis has a longer rostrum, about half the length of the carapace, consisting of 2 spinelike processes instead of flattened ones. It also decorates itself, which this species usually does not do. Cancer gracilis is a cancer crab. Pugettia producta grows much larger and has a smooth dorsal carapace surface.

Geographical Range: Attu Island to Monterey Bay, CA. Common in Monterey Bay.

Depth Range: Low intertidal to 140 m. Young are often among eelgrass.