Sea Star Wasting is Not a Party

When I arrived at the Port Townsend Marine Science Center (PTMSC) from Texas, I was prepared to show off my knowledge of marine mammals while learning more about other organisms such as birds and invertebrates. Little did I know that I frequently made a common slip – “starfish? Don’t you mean sea star?” After decades of confusion, scientists have pushed for a change from starfish to sea star, and nobody told me! If you’re lucky, you can catch me for an easy opportunity to poke fun at this simple transition.  

A blood star (Henricia leviuscula) with abnormal arm growth. Photo: PTMSC

I knew these invertebrate animals were named for their trademark five-armed, radial symmetry, and are not fish. More than 2,000 species of colorful sea stars sport five arms, even though some species can have 10, 20, or up to 50 arms. It is also not unusual for a five-armed sea star to have six arms due to abnormal growth.

Sea stars are echinoderms, which translates to “spiny skin.” Their living relatives include sea cucumbers, sea urchins, and sand dollars. The PTMSC Marine Exhibit hosts all of these, with short to long spines, and colors ranging from purple, pink, and orange!

I had never felt a sea star’s leathery skin before I began working at the Marine Science Center, nor was I aware of how varied the colors can be. They use colors as camouflage in a number of environments, ranging from tide pools to more than 6,000 m below sea level. The sea stars in the Marine Exhibit (ME) are a deep purple, peach, or neon orange, and are within your reach. Sea stars move and flex using a water vascular system. They pump seawater through their body, filling and emptying tiny, suction-cupped tube feet to extend, retract, or even create suction to scale any surface. One leather star (Dermasterias imbricata) even used its tube feet in an effort to help clean their tide pool tank! The tube the star is grasping a gravel tube, which staff and volunteers use to clean the gravel of the tanks, while in the meantime picking out any discarded clam shells from a sea star’s previous feast.

Giant Pink Star helping to clean. Photo: Mattie Stephens

Most sea stars also have the amazing ability to consume prey outside their bodies. Using their tube feet, they pry open clams or oysters.  Then, the upper portion of their stomach (known as the cardiac stomach) emerges from their mouth and oozes inside the shell. The clam’s muscles tire against the strong, hydraulically operated tube feet, and eventually open. The stomach then envelops the prey to digest it, eventually withdrawing back into the body.  At this point, the lower, or pyloric, stomach digests whatever is remaining.

Sea stars are famous for their ability to regrow limbs and entire bodies. This feat is possible by housing most or all of their vital organs in their arms. Rarely, the “central body disc must be intact to regenerate, but a few species can grow an entirely new sea star just from a portion of a severed limb” (National Geographic, 2016). Sea stars can willingly detach an arm to distract a predator to get away, or in a method of reproduction. There is a spreading epidemic of arms shedding and sea stars dying due to disease (National Geographic, 2016).

What factors cause these arms to shed unwillingly? Sea stars have been known to suffer from desiccation, or drying out, resulting in lost limbs. However, even healthy sea stars can suffer from sea star wasting disease. This disease causes rapid tissue degradation in sea stars, resulting in lesions on the arms and the body deflating (referred to as a loss in turgor pressure), giving the sea star a melted appearance. The process happens quickly, fully enveloping a sea star within three days, usually ending in death. The disease can spread between individuals, and has resulted in devastating losses, not only in natural habitats, but in aquariums as well. A few weeks ago, I watched as PTMSC lost its last mottled star to sea star wasting. Over the past few years, over 50% of the sea stars in the Marine Exhibit have succumbed to wasting.  

Top: An infected arm of a mottle star (Evasterias troscheli)
losing water pressure. Photo: PTMSC
Bottom: A mottled star succumbing to sea star 
wasting disease

PTMSC is taking part in monitoring this devastating process. Sea star wasting can cause large die-offs of these important animals, and although sea stars are slow moving, they are instrumental in maintaining a healthy ecosystem. The health of the ecosystem would crumble without sea stars, making them what is known as a keystone species. Sea stars help keep their tide pool and coastal ecosystems in check. PTMSC citizen science volunteers participate in a quarterly survey on Indian Island, where they monitor plots designed to observe the health of local sea star populations. This year, November survey team, led by fellow AmeriCorps Juhi LaFuente, observed numerous healthy ochre (Pisaster ochraceus), sunflower (Pycnopodia helianthoides), and mottled stars (Evasterias troscheli); these species tend to be the first affected by the virus. This is good news for our scaly friends, as it indicates there may be a shift towards reduced die-offs and a slowly recovering ecosystem.

Sun Star discovered in this year’s monitoring program. Photo: Betsy Carlton

The ecosystem recovery process will take a long time. Activists and citizen scientists are working hard on improving the overall health of the ocean, as even the slightest increase in temperature can wreak havoc on an ecosystem. The Marine Exhibit and Natural History Exhibit have taught me several ways that I can individually reduce my impact and waste output. Living in Port Townsend has illuminated healthier living practices for me, and I have been embraced by an environmentally conscious town. The more I learn about sea star wasting, the more pressing environmental stewardship becomes.

Please consider donating today. https://ptmsc.org/get-involved/donate

- Mattie Stephens is the Marine Mammal Stranding Network Coordinator/Educator and AmeriCorps member serving at the Port Townsend Marine Science Center

Sea Star Wasting Monitoring: Countdown to Low Tide

Most regular people spent the evening of Tuesday, November 24^th preparing for Thanksgiving. People all over the country made pumpkin pies, baked casseroles, and picked squashes. Some people went on long runs to increase their appetites and others ate big meals to stretch their stomachs in preparation for the big night. However, a small, nerdy handful of people did none of those things. These intrepid adventurers got ready for Thanksgiving by braving the wind and the cold to count sea stars. I was lucky enough to be one of those nerds, and below is the story of that adventure.

The third Tuesday in November was the seasonal survey of our long-term sea star monitoring plots at Indian Island County Park. The PTMSC has monitored these plots four times a year ever since the 2013 Sea Star Wasting Disease outbreak. We are partners in a West Coast monitoring program coordinated by the Multi-Agency Rocky Intertidal Network (MARINe) designed to monitor the health of sea star populations and severity of disease outbreaks. 

Tuesday afternoon I packed a backpack with all the necessary supplies. Data sheets, check. Bleach solution, check. Tiny tape measures, check. As I gathered the equipment and chatted with volunteers, I felt the familiar buzz of fieldwork anticipation. At 3:30 pm, I was set to go. Only five hours and seven minutes until low tide. When searching for sea stars, it’s best to wait for the water level to drop.

I popped into the staff meeting and the mood was excited and interested. Everyone was anxious to hear how our local stars were faring. The wind picked up outside, but I didn’t think anything of it until the lights flickered and went out. And stayed out. 20 minutes later, I was still tapping my foot, willing the power to come back on. At the Marine Science Center, no power means no pumps. When the pumps go off, the fish and invertebrates in the aquarium get understandably unhappy. If the power stayed off, it would be time to bust out the backup generator for the second time this month. I already had a long night ahead of me and was not quite ready for that. Just before 5 pm, the lights flickered back on and I raced out to the Marine Exhibit. With the pumps whirring and the alarm reset, I was ready for dinner. Three hours and sixteen minutes until low tide.

Kitz, planning his next bit of mischief.

I walked in my front door to find my (saintly) housemate and AmeriCorps teammate, Zofia, cooking spaghetti for dinner. And there was my (notably less saintly) cat, playing with a toy in the living room. But on second glance, it wasn’t a toy. It was a real live mouse. After one failed attempt to sh(r)ew it out the door, I gave up. “Kitz,” I said sternly to my cat, “You brought that mouse into this house and it’s your job to take it out.” Then I stomped off to put on as many layers as I could. Arm movement comfortably impeded, I sat on the couch and tried not to imagine the next time I’d see my new furry housemate. Two hours and forty minutes to go.

The view between the boulders.

The wind buffeted the car on the ride to Indian Island. There were downed trees and branches all along the road. Earlier, I had consulted the other members of the Sea Star Monitoring Team and we had decided that the conditions might be uncomfortable but were unlikely to be dangerous. Carolyn, Zofia, Betsy, and I arrived at the pitch black Indian Island County Park where we met volunteers Dennis and Howard. Two hours until low tide and we needed to relocate the survey markers that denote the corners of our plot. 

Good thing we arrived early. It took forty-five minutes, but we managed to find all the requisite survey markers. We even had a few extra minutes to collect burrowing sea cucumbers. These orange, squishy creatures are aptly named. They burrow into sand and wedge in between boulders to protect themselves from wave shock and predation. They also happen to be the favorite snack of our Stimpson’s sun star and it was time to stock up for the winter. One hour and seven minutes.

Howard Teas teaches the group about mottled star identification.

Toni and Rich, two more dedicated citizen scientists arrived to help with the survey. Once they were suited up, we got rolling. In pairs, we surveyed parallel transects through our two adjacent plots. We needed to check in every crevice and under every rock. However, to reduce the negative impact of the monitoring on our study site, we do not turn over rocks in search of stars. Instead, we crawled along the ground, bent over rocks, lay on our bellies and struck all manner of undignified poses (we aim for every stone unturned)! We found a wonderful assortment of amazing organisms under those rocks —white sea cucumbers, coralline algae, and chitons galore — including a handful of healthy sea stars. As 8:37 pm came and went, the tide went slack at -1.48 feet, and we started to wrap up. Within our plots, we saw large and small healthy ochre, mottled, and six-rayed sea stars. We even saw a large blood star just outside of our study area. Each of them gave us a little bit of hope that sea star wasting might be waning once more. Although this disease will likely be present for years to come, it bolsters my optimism to see resiliency in this wild population we love so much. 

Here are a few photos from our survey: 

A healthy mottled star

A healthy blood star

A healthy ochre star

The crew surveys plot 2.

Zofia lies down for a better look at this ochre star. 

—

REBECCA MOSTOW is the Marine Exhibit Educator and an AmeriCorps member serving at the Port Townsend Marine Science Center.

Sea Star Wasting Strikes Again

Today through Friday, 12/18, the Port Townsend Marine Science Center is seeking to meet a $3,000 match challenge from a generous donor. Donate today and every dollar you give will go twice as far. With your help, we will meet our goal of raising $15,000 for our annual fund to double our impact next year. Thank you for helping to inspire conservation of the Salish Sea and monitor the health of our local ocean.

During my first week at the Port Townsend Marine Science Center, our tanks suffered a minor catastrophe. We had another small bloom of sea star wasting disease, a notorious viral infection that has been killing off sea stars all along the north Pacific coast. 

I have personally seen the effects of wasting on beaches from Alaska to California, so I was anxious to see it in a captive setting. It’s a pretty depressing progression, that’s for sure. I watched four sunflower stars (Pycnopodia helianthiodes) progress from behaving unnaturally to losing limbs in a matter of a few days. 

However upsetting the disease is, it is fascinating and heartening to see the work the PTMSC is putting in to tracking and understanding it. Along with other aquaria, the PTMSC observers noted that the first stage of the disease is a behavioral one. Stars act lethargic and twist their arms across one another. This observation has allowed the Science Center volunteers and staff to detect the presence of the disease before any animals show more classic physical symptoms. 

The PTMSC runs a citizen science monitoring program of its tanks and of nearby subtidal and intertidal plots. Volunteers and staff gather data on the health of many different species and populations of stars in Strait of Jaun de Fuca water. These data are shared with the University of California Santa Cruz and other organizations monitoring the disease. 

Hopefully we are contributing to a better understanding of the disease, its symptoms, and its spread in our ecosystem.

A sunflower star with wasting that has started to lose limbs. 

A sunflower star with wasting. Note the white lesions and deflated appearance.

Zofia and me removing a sick sea star from the cluster tanks. I was very close to trading places with the sea star that day! 

—

REBECCA MOSTOW is the Marine Exhibit Educator and an AmeriCorps member at the Port Townsend Marine Science Center.

Sea Star Wasting Annual Report

Are you curious about the data our citizen scientists have been collecting about sea star wasting?
We have finally finished putting together our sea star wasting annual report.
The report shows observations and patterns that we've seen in the Port Townsend Marine Science Center tanks, as well as in our plots at Indian Island County Park, Port Hadlock, WA.

It's been a busy year for the Port Townsend Marine Science Center, and our work collecting data is far from over as we seek to understand the changes that we'll be seeing for our sea stars in the future.