Red Rock Crab (Cancer productus): The Heavy Hand at the Kelp's Edge
Cancer productus owns the rocky shallows of the Pacific coast: crushing claws, black-tipped pincers, and a quiet role policing urchins. ID, biology, fishery.
Dr. Mara Ellison ·
10 articles
Cancer productus owns the rocky shallows of the Pacific coast: crushing claws, black-tipped pincers, and a quiet role policing urchins. ID, biology, fishery.
Dr. Mara Ellison ·
The California sheep crab is a slow, spiny giant of the kelp forest floor — a decorator crab that outgrew its disguise. Meet Loxorhynchus grandis.
Dr. Mara Ellison ·
Carcinus maenas is Europe's toughest shore crab — a kelp-edge scavenger at home and one of the world's most consequential marine invaders everywhere else.
Dr. Mara Ellison ·
Necora puber — red eyes, velvety shell, paddle legs and a famous temper — is the reef's feistiest crab from Norway to Iberia, and a quiet kelp-forest worker.
Tom Okafor ·
Kelp crabs graze the very forest they live in. How Pugettia producta clips, prunes and cleans kelp fronds — and why predators keep the shears in check.
Dr. Theo Nakamura ·
The northern kelp crab is a colour-changing spider crab that lives its whole life in the kelp canopy. Learn its biology, diet, and role in the forest.
Dr. Theo Nakamura ·

Meet the sharpnose crab — a small Pacific spider crab that plants living algae on hooked hairs across its shell. How the disguise works and where to find it.
Dr. Mara Ellison ·
Meet the heart crab — a flattened, heart-shaped California reef crab that is not a true crab at all, but a king-crab relative descended from hermit ancestors.
Dr. Theo Nakamura ·
Graceful crab species profile: the slim Metacarcinus gracilis of eelgrass, bays and kelp edges — how to tell it from a small Dungeness, and its estuary role.
Dr. Mara Ellison ·
Helmet crab species profile: the saw-edged, bristled Telmessus cheiragonus — a night-roaming burrower of kelp coast sand from Alaska to Japan.
Dr. Mara Ellison ·