SEATTLE — Every year toxic algae blooms along the Northwest coast - infecting shellfish and shutting down shellfish beds for harvest.
If people eat these poisoned shellfish they can become sick or die from what’s called Paralytic Shellfish Poisoning.
The algae occur naturally but for decades the shellfish industry and public health officials have been struggling to predict where the blooms will happen.
Stephanie Moore, an expert on harmful algal blooms with the Northwest Fisheries Science Center, is on a mission to find out where these algae sleep. She’s standing on the deck of the Clifford Barnes – a 65-foot research vessel heading out of Ballard Harbor in Seattle.
We reach the first sampling station and the team lowers a device over the side to collect muck from the bottom of the Sound - muck that could be full of sleeping algae – or cysts. By understanding where the next generation of algae is lying dormant, Moore and her team hope to help the shellfish industry and public health officials predict where the next toxic blooms could occur.
“So right now we’re lowering our corer down to get a sediment sample,” Moore explains as the long tube-shaped device disappears beneath the water. “These guys have this dormant resting cyst stage over winter and there are cues that tell them to germinate and swim to the surface and start growing.”
The algae Moore is talking about is called Alexandrium. It’s a sort of super bug – half plant, half animal. This single-celled organism has a whip-like tale that propels it through the water.
Oh, and it can photosynthesize – so once it swims from the depths up to the sunlight in the warmer weather it starts to divide… and divide… and divide – until it’s formed what’s called a bloom. That’s what makes shellfish, and potentially people, sick.
The ship’s crane raises the corer from over 600 feet below. It’s like a drinking straw, half full of chocolate mucky-milkshake.
From here, the mud is taken into the onboard lab where Julie Masura, a researcher with the University of Washington Tacoma, prepares it to go under the microscope when the team gets back to shore.
Masura has spent a lot of time looking at these super-beasts under the microscope.
“We stain them and they fluoresce kind of like green jelly beans so they remind me of those lights at a disco club, the fluorescent lights and that’s what they look like when we stain them and so I count them.”
The team has found a connection between high levels of cysts and high levels of poisoned shellfish in certain areas. But Masura says they need to do more research to better understand that link.
No one has died from Paralytic Shellfish Poisoning here since the forties but every year shellfish beds in Washington and Oregon are closed because of dangerous levels of toxins from these algae.
The toxins don’t go away when shellfish are cooked or frozen, posing a problem for health officials.
Frank Cox, with the state Department of Health, says Washington has some of the most toxic shellfish in the world when it comes to Paralytic Shellfish Poisoning. His group tests thousands of shellfish for toxin levels every year.
“The program that we have is effective but it would be better if we were able to have a predictive tool that would tell us in advance when these shellfish are going to be coming significantly toxic like that,” Cox says.
That’s where Stephanie Moore, Julie Masura and the rest of the research team aboard the Clifford Barnes come in.
“We want to be able to say when and where there is a really strong chance of a bloom occurring,” Moore says that way shellfish growers and the health managers can put in place some strategies to try and limit the impacts that these blooms can have.
In 2010 shellfish tested at 25 sites around Washington contained record-high levels of toxins from these algae.
View Paralytic Shellfish Poisoning Hotspots from Department of Health in a larger map
The above map shows the sites where shellfish set records for levels of paralytic shellfish toxin. The red dots represent sites where the levels were lethal for human consumption. All sites were well above the Department of Health’s accepted levels. Note: there are many other sites further south in Puget Sound that are above safe levels - this map just shows the record-setters.
Moore says scientists have a lot to learn about what triggers these blooms, and why the algae release toxins when they do.
One thing’s certain though: these creatures love warm sunshine-filled water and she says they may be getting a lot more of those conditions in the future.
“We might see blooms occurring much earlier in the year, up to two months earlier in the year, because water temps are going to be warming up a lot earlier in the year. Blooms could also last a little bit later.”
Ok, so if scientists can figure out where the algae are sleeping, why don’t they go in and remove them?
Moore says she’s heard of a Japanese researcher discussing a remote-controlled device that was going to do just that: vacuum the bottom of the ocean.
But she says that would probably cost a whole lot of money, disrupt the ecosystem and the algae would eventually come back anyway. There are no plans to remove the toxic algae in Washington.
So, no underwater algae-sucking roombas for now, but some pretty solid modeling for where these toxic algae could be appearing in the future.
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