Neal Smith

The effects of seabed slope and other environmental variables on the movement patterns of giant Pacific octopuses (Enteroctopus dofleini)

Using VEMCO VPS acoustic technology, we captured, tagged, and tracked 15 giant pacific octopuses (Enteroctopus dofleini) within Eldred Passage, in Kachemak Bay, Alaska. Octopuses ranged from 3 to 13.6kg, occupying depths from 32 to 92ft.

This study provides new insight into using VPS technology in deeper waters, as previous studies with VPS have been in shallow waters. Minimum Convex Polygon’s (MCP’s) for area use in octopuses ranged from 5,125 m2 to 381,480 m. Three of the octopuses displayed steadily increasing MCP’s well over 20 days after release. Calculated octopus positions were mapped over seabed slope data, and one can visually observe octopuses to prefer and move on or close to steeper sloped areas.

We are now examining the effects of depth, seabed slope, and temperature on the movement rates of these animals. This study provides insight into tracking octopuses in deeper waters, and suggests that slope may be an important factor in habitat selection for octopuses.