The Pacific Northwest tree octopus (Octopus paxarbolis) can be found in the temperate rainforests of the Olympic Peninsula on the west coast of North America. Their primary habitat lies on the Eastern side of the Olympic mountain range, adjacent to Hood Canal. They can sometimes be found in other temperate rainforests of the Pacific Northwest states and British Columbia These solitary cephalopods reach an average size (measured from arm-tip to mantle-tip,) of 30-33 cm. Unlike most other cephalopods, tree octopuses are amphibious, spending only their early life and the period of their mating season in their ancestral aquatic environment. Because of the moistness of the rainforests and specialized skin adaptations, they are able to keep from becoming desiccated for prolonged periods of time, but given the chance, they would prefer resting in pooled water.
An intelligent and inquisitive being (it has the largest brain-to-body ratio for any mollusk), the tree octopus explores its arboreal world by both touch and sight. Adaptations its ancestors originally evolved in the three-dimensional environment of the sea have been put to good use in the spatially complex maze of the coniferous rainforests. The challenges and richness of this environment (and the intimate way in which it interacts with it,) may account for the tree octopus's advanced behavioural development. (Some evolutionary theorists suppose that "arboreal adaptation" is what laid the groundwork in primates for the evolution of the human mind.)
Tree octopuses have eyesight comparable to humans. Besides allowing them to see their prey and environment, it helps them in inter-octopus relations. Although they are not social animals like us, they display to one-another their emotions through their ability to change the colour of their skin: red indicates anger, white fear, while they normally maintain a mottled brown tone to blend in with the background.
The reproductive cycle of the tree octopus is still linked to its roots in the waters of the Puget Sound and the Salish Sea from where it is thought to have originated. Every year, in Spring, tree octopuses leave their homes in the Olympic National Forest and migrate towards the shore and, eventually, their spawning grounds in Hood Canal. There may be other as yet unmapped spawning grounds elsewhere in the Salish Sea. There, they congregate (the only real social time in their lives,) and find mates. After the male has deposited his sperm, he returns to the forests, leaving the female to find an aquatic lair in which to attach her strands of egg-clusters. The female will guard and care for her eggs until they hatch, refusing even to eat, and usually dying from her selflessness. The young will spend the first month or so floating through Hood Canal, Admiralty Inlet, and the Salish Sea before eventually moving out of the water and beginning their adult lives.
There may be blackberry canes in the cedar tree. Use caution to avoid being donating blood. Please respect park hours and do not attempt at night. Park is open from 1 hour before sunrise to 1 hour after sunset.