8 legs, new tattoo, what’s an octopus to do?

By Naomi Klouda

Photo courtesy of Homer Tribune. A giant octopus is found aboard a fishing vessel.

Homer Tribune

What marine animal can unscrew the lid of a jar, squeeze into a water jug, shoot out clouds of ink to mimic its own shape and tear off scientific tags meant to track him?

The octopus holds uncanny intelligence indicating an ability to problem solve, said marine biologist and diver, Reid Brewer. He is at work on a doctorate with the University of Alaska Fairbanks as he gathers baseline studies of octopus habitat. Large crowds attended his weekend lectures during the National Wildlife Month at the Alaska Islands and Ocean Visitor Center in Homer. The talk, “Octopus and other creatures run wild,” was accompanied by photos of the cephalopod’s little-known underwater world off the Aleutian Islands.

“This is such a fun talk to give because people really like to hear about octopus, and they are really curious about these creatures,” Brewer said. “This especially is a popular topic with fishermen. For a lot of people, the octopus is an amazing, favorite critter.”

Giant octopus are rumored to be up to 30 feet long. But the largest Brewer ever witnessed came to 18 feet and weighed about 600 pounds.

Brewer gives out vials of ink from octopus gathered in his two-year study. More than just the children were reaching out to claim one after Saturday’s talk.

A first step in gathering good data involved solving the tagging problem. Brewer used new tagging technology to outwit the clever octopus: tiny, bright, flexible tags that show through the octopus’ skin after they are implanted.

“Different colors are mixed up and injected just under the skin into little dots that are noninvasive,” Brewer said. To distinguish individuals, he used different dot-color patterns in the tattoolike tagging.

He has tagged 1,700 and recovered 220 to 230 over the two summer study seasons. He is trying to get a handle on the population size off of the Aleutians and learn how far they range across their waters. Not far, the answer may be. He has found them shifted by only a kilometer in two to three months.

“Scientists haven’t learned enough about octopus in Alaska to provide for an ecosystem approach to management,” Brewer said. “We know that people use octopus for bait, they throw them back over the side of the boat when accidently caught, and they sometimes eat it. But we don’t know how many that is. We also don’t know how far they range and population sizes.”

The population estimates so far indicate octopus numbers may be as much as two orders of magnitude larger than estimated, about 200 to 600 octopus per square kilometer.

The knowledge researchers gain will be valuable on its own to reveal details of a little-understood invertebrate, but will be even more so if anyone proposes an octopus fishery in Alaska, he said. The information could also have ramifications for by-caught octopus.

Octopus caught accidentally in groundfish fisheries in federal waters off Alaska may be sold, but there is no commercial octopus fishery in federal waters. In state waters, within three miles of the coastline, directed octopus fishing is allowed only with a special commissioner’s permit from the Alaska Department of Fish and Game.

“If we’re going to be ready to manage Alaskan octopus as a commercial species, we need know a lot more about them, starting with their reproductive seasons,” Brewer said.

Brewer also showed slides from the 100 photos collected and published in a team-complied book of which he is the primary author, “Under Aleutian Waters: A Look at an Undiscovered Ecosystem in the Presence of Changing Climate.”

The footage of never-before-seen areas in the waters off the Aleutian Islands was shown as a Friday evening lecture. One of the most exciting findings, he said, was the discovery of the 8-foot Golden V kelp that fans out into a giant V. National Oceanic and Atmospheric Association scientist Mandy Lindeberg first spotted the new species near Kagamil Island in the central Aleutian Islands of Alaska while participating in an Alaska Department of Conservation coastal survey in 2006.

The Golden V kelp was discovered in cold, clear water attached to large boulders in the shallow subtidal zone. The kelp can grow up to 9 feet long and have a paddle-shaped leaf with a golden-yellow stem. The holdfast — the portion of the kelp that attaches to the rock — is an unusual disc shape which can withstand high-energy waves frequently encountered in the Aleutian Islands.

They also found a new sea star species and new species of chitons, or mollusks. Some 25 to 30 species were documented, with 60 shown to range beyond what scientists had believed was their territory. The team had dived to 50 different sites over the study period from 2005 to 2007, made 2,000 dives total and collected 8,000 photos.

Brewer lives in Dutch Harbor as the Marine Advisory Program agent.

Brewer’s lecture discussed the importance of diversity in nearshore ecosystems and highlighted new species discovered in 2007.

Brewer is an assistant professor with UAF and has been based in Unalaska and Dutch Harbor for the past four years. He splits his time in the Aleutian Islands between marine-related education, outreach and research. He also is a scientific diver and an invertebrate taxonomist.

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