Mussel infestation of the Barrier Queen

The mussel infestation of the Barrier Queen turns a mechanical failure into an ecological puzzle: mussels have blocked the ship’s rudder, spread across its propeller and hull, and apparently reached it far from shore. Leon Anawak’s account offers a plausible sequence for how the vessel became immobilized, while later examination reveals mussels capable of swimming under their own power. Yet the infestation does not explain everything Anawak finds beneath the crust: a fragment of unfamiliar tissue, associated with a single flash of light, remains unidentified.

The blockage and its mechanics

The infestation first becomes legible through the rudder. When Clive Roberts asks whether mussels blocked it, Anawak confirms that they appeared to be zebra mussels. He then lays out a reconstruction rather than a confirmed account. A helmsman tries to turn the rudder by five degrees, but it does not move because mussels have settled across the shaft. Assuming that the rudder has not been shifted far enough, the helmsman applies more force. When the rudder finally breaks free, it crushes the mussels in its path; their ground-up bodies form a paste that wedges the blade so it cannot swing back across the shaft.

Anawak’s explanation makes the failure a chain reaction. The rudder does not simply encounter an obstruction: the attempt to overcome the obstruction produces a second one. What should have been a moving blade becomes trapped by the material it has crushed. The ship’s ordinary controls have, in this reconstruction, turned the infestation into a lock.

From a jammed rudder to an occupied hull

The distribution of the mussels raises a harder question than the blocked rudder alone. Anawak points out that the sea-chests are clear, while the propeller is completely infested. He doubts that mussels could attach themselves to a rotating propeller, and considers their having boarded in Japan unlikely: the rudder had functioned normally until the ship reached the two-hundred-mile zone. He therefore proposes that they attached to the propeller after the engine stopped.

In his imagined sequence, a large swarm settles on the rudder and jams it. The ship heels; within minutes, the engines are shut down, and the propeller stops rotating. Mussels continue to descend on the rudder, strengthening the blockade, then spread over the propeller and along the hull. Anawak describes the ship as having been taken over, while carefully presenting this account as an attempt to picture what happened, not as a witnessed history. Roberts’s bewilderment supplies the unresolved scale of the problem: the Barrier Queen was out at sea, where the tonnes of adult mussels covering it could not be easily explained.

The condition of the hull makes the infestation more difficult to dismiss as ordinary fouling. Roberts says the ship is constantly inspected and protected by environmentally friendly special paint, which should admit few attachments beyond perhaps a handful of barnacles. Anawak counters that there are far more than a few barnacles. The Barrier Queen looks, he says, as if it has been exposed for weeks to hordes of mussel larvae. The contrast between routine inspections and the unexpected crust shifts attention from a neglected surface to an abnormal colonization.

The “jet mussels”

Sue Oliviera reports that the mussels do not appear in existing research. They resemble zebra mussels and form colonies in the same way, but their byssus—the fibres extending from the foot—is unusually thick and long. Whether they are a related species or a mutation remains unsettled. Oliviera gives the specimens the provisional nickname “jet mussels,” emphasizing that their movement, not just their appearance, sets them apart.

Rather than drifting like ordinary zebra mussels, the living specimens draw in water and expel it to propel themselves. Their fibres help them steer. Oliviera compares this movement first to jet propulsion in some squid and then to the motion of certain dinoflagellates, whose flagella can steer and drive a cell forward. She treats the resemblance as convergent evolution in a broad sense, not evidence that the organisms are closely related. In her account, the mussels can move like shoaling fish and maintain their momentum despite the weight of their shells.

That capacity offers a possible answer to the Barrier Queen’s offshore infestation. If mussels can propel and steer themselves, their presence on a ship in the middle of the ocean is less inexplicable than it would be for organisms that only drift. But the explanation remains partial: it suggests how they could reach the hull, not the precise source or timing of the swarm Anawak imagines descending on the ship. The infestation is thus both a mechanical obstruction and evidence of unfamiliar mobility.

The light and the unidentified tissue

During his inspection beneath the crust, Anawak encounters something else. As he recounts it to Roberts, something shoots out toward him from inside the mussels. The memory returns in stages: the shock, his head striking the boat, and what he first takes for stars. He corrects himself—the lights were flashes, and there was a single flash. The recollection places a brief, uncertain encounter inside the larger physical mass of the infestation.

Oliviera’s examination does not identify the tissue Anawak collected. Most of it has already decomposed, leaving only a small amount available for analysis. That material appears identical to the substance found on the propeller and on Anawak’s knife, but resembles nothing the researchers have encountered before. Oliviera describes it as unusually contractile, extremely strong, and highly elastic. The shared substance connects the propeller evidence to Anawak’s encounter, without establishing what produced it or whether it belongs to the mussels.

When Anawak asks whether the tissue could indicate bioluminescence, Oliviera allows that it is possible. The suggestion sits beside, but does not settle, his report of the flash. The infestation therefore yields two different kinds of evidence: a mobile mussel colony that may account for the ship’s immobilization, and an unidentified tissue whose elasticity and possible relation to light remain open questions. The Barrier Queen’s disablement can be reconstructed; the life concealed within its crust cannot yet be named.