Thursday, February 2, 2023

A giant Pacific octopus is released to the Salish Sea

Marley Loomis has been keeping track of the giant Pacific octopus (GPO) at the Port Townsend Marine Science Center ever since she left her position as an AmeriCorps member there from 2018-2020. When PTMSC determined it was time to release the cephalopod, Marley knew she had to be there.


In 2020, Marley spotted the young octopus while sorting zooplankton from a research trap. As part of an effort by the Pacific Northwest Crab Research Group (PCRG) to support sustainable Dungeness crab fisheries, the trap collects a nightly assortment of zooplankton including many species of young fish and invertebrates. The primary goal is to identify and count the Dungeness crab megalopa which, together with the other zooplankton collected, is then returned to the water. Occasionally, small numbers of select species are reared in the aquarium to represent the diversity of marine life found here. Although still a paralarva, the tiny octopus was starting to transition from floating in the water column to clinging to surfaces. It was a rare and exciting opportunity to raise a giant Pacific octopus.


Loomis assisted PTMSC Aquarium Curator Ali Redman in raising the octopus while documenting his growth and development. Over the next two years Sylvia, named by donors in honor of marine scientist Sylvia Earle, thrived in PTMSC’s aquarium at Fort Worden. Given that there are only a handful of accounts of rearing giant Pacific octopuses, Marley and Ali are thrilled with Sylvia’s success!


Octopuses are relatively short lived, with the lifespan of a giant Pacific octopus being about 3-5 years. Giant Pacific octopus are “small egged”, meaning that they produce a large number of relatively undeveloped offspring. Unlike “large egged” octopus that look like tiny adults when hatching, GPOs start life as tiny paralarvae drifting with the currents. In both reproductive strategies, parental care focuses on the eggs and hatched young explore and learn on their own. 


Octopuses mate at the end of their life, then pass away following a period of decline known as senescence. As adults, they become more active, eat less and devote most of their resources to mating. A male GPO may live about 1 month after mating, females will survive a little longer, caring for their eggs until they too pass away. It is because of this unusual life history that captive octopus are well suited to release. 


“Determining when an octopus has reached maturity, and is therefore ready for release, is important for animal welfare,” said PTMSC Aquarium Curator Ali Redman. “We continually monitor behavioral and physiological indicators with the goal of releasing octopuses before senescence.”


An avid diver, Marley is a graduate student at Alaska Pacific University, studying marine biology, specializing in octopus behavior. She traveled to Port Townsend with her drysuit and her partner James Gomez DeMolina, who is also trained in marine biology.


“I flew down from Alaska because I felt directly tied and attached to this project of raising Sylvia at PTMSC,” Marley said. “I’ve been pretty invested in his development and have spent so many hours working with him and making sure he has appropriate resources and has everything he needs to grow and be successful, and I’ve also seen how much impact he’s made on the community.”


Emilee Carpenter and Ali Redman wait
on the pier for the divers to arrive.

Ali directed the release, assisted by Aquarium Specialist Emilee Carpenter at the surface. Mandi Johnson, PTMSC Outreach Coordinator, who has also been part of Sylvia’s care team since his arrival, conducted an initial scouting dive with volunteer Glenn Grant a week before, identifying an appropriate area for release. The Friday prior to the release,Marley and James identified and marked a den site that would provide Sylvia with shelter as he adjusts to his new surroundings. 


On the day of the release, Ali and Emilee assisted Sylvia into a mesh transfer bag. Octopuses are comfortable out of water for short periods of time and Sylvia routinely climbed into a basket to be lifted from the water and weighed. This time, rather than returning to the exhibit, he was lowered from the pier to the divers below.


Marley and James were joined by Mandi and Grant for the release dive on a day with light winds and scattered clouds. Mandi and Glenn were equipped with two GoPro cameras and an underwater light.


“It was as smooth as possible. Everything that we had planned out went as well as we could have imagined it. We knew exactly where we were going, he behaved beautifully, he was really calm the entire time in the mesh bag when we were descending and on our way to the site,” Marley recounted.

Marley Loomis takes ahold of the
transfer bag prior to the release


“I opened up the bag, opened it up right next to this big hollow piling, which we thought was a nice den spot for him. And he just casually walked right into it and took up his space. We offered him a (live Dungeness) crab and he reached out and touched it and then decided, ‘No, I really don’t want that crab right now,’ so he didn’t take the crab. But he knew it was there and it was absolutely as smooth as possible. Nothing could have gone more smoothly. And the day was gorgeous,” Marley said.


As the divers swam back to the beach, the release team walked off the pier to welcome them and were ready with towels and good wishes on a job well done. With a water temperature of 46 degrees, the dive had to have been a cold one.


We aren’t able to know exactly what becomes of Sylvia after his release. GPS enabled tags can’t transmit underwater nor can they be attached to his soft body. Since local live foods have been part of his diet at PTMSC he will be able to find food. However, he may not have much of an appetite. It’s likely he will focus on finding a mate. He may find one here, or he may move out of the area. Once male GPOs have mated, they enter senescence and will pass away in about one month. Nevertheless,one can’t help but wonder if Marley had imagined Sylvia’s life at sea, and she admitted she had.


“I mean, it's human nature to think about what's going on beyond what we can see, for sure,” she said. “Mandi and James and I all did an afternoon dive somewhere else, and when we came back, Mandi and I were like,’Man that would be really cool just to dive down and see if he’s still there.’ 


But honestly, anything that happens from now on out is a totally natural part of the food web. If he’s able to find a mate and reproduce, that’s fabulous. If he just lives out his life and rejoins the food web, then that’s great, too. I’m not too worried about him. Since he took up a nice little den space, there’s so much crabs down there, there’s so much food for him. I’m not too worried. Whatever he is doing is natural in the Salish Sea,” said Marley.


Back in Anchorage, Marley is conducting a research study on a particular octopus behavior, called a head bob. 


“Octopuses have mainly monocular vision, they don’t have the same depth perception that we do with their field of vision, with both eyeballs overlapping,” Marley explained.


“There’s evidence that the head bob behavior is mostly a ranging and depth perception behavior, but there is not any published numerical data on proving that, so I am effectively trying to quantify a head bob behavior to link it to depth perception for octopuses.”


Marley’s future seems certain to be a bright one, although she has some decisions to make in the near future: 


“I’m torn between further pursuing behavioral and ecological research or rejoining the public education and aquarium sciences field,” she said. “I am really passionate about both of those areas and honestly I alternate back and forth weekly on which of those two paths I will follow. Either path is not wrong.”


PTMSC’s experience raising octopus in captivity has certainly made an impact on our community. Over 500 visitors toured the aquarium for a special weekend opening to see Sylvia one last time. The video Ali made of Sylvia’s release has over 1,500 views at the time of this writing. (YouTube link)


Marley Loomis is greeted by her father Michael Loomis
as James Gomez DeMolina dries off after the dive.

“I just think that the release and all that Sylvia helped to accomplish speaks to the community in Port Townsend and all of PTMSC,” Marley said. “You know it’s bittersweet to release him, but it’s more sweet than bitter. It's a success story. He grew very successfully and impacted a lot of people over the course of the two and a half years he was there and now he’s back out to reproduce. I’m really proud of what we’ve done. I think that PTMSC would probably say the same about how they feel about it. It's such a testament to how impactful those animals can be for people coming in to see him and how involved the community feels in what we’re doing. It’s spectacular. I’m overjoyed with it all, honestly. I'm so happy I could be part of it all, it was lovely.”


Ali and Emilee are currently nurturing another GPO, which was also brought up incidentally in the light trap. Not yet a year old and currently about the size of a strawberry, the octopus will be inspiring visitors when the aquarium reopens this spring.

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